Operating Manual HB552540 7955 Flow Computer May 2010 ... · You obey any other common-sense precautions which may apply to your situation. If you obey these sensible precautions,

Liquid Flow Computer Manual (2540 software) 7955 Flow Computer

Operating Manual HB552540 May 2010

7955

Introduction: The 7955 liquid flow computer can be used for quad-stream applications. Software Version:

2540 – Liquid Applications.

Emerson Process Management (EPM) pursues a policy of continuous development and product improvement. The information contained in this document is, therefore, subject to change without notice. To the best of our knowledge, the information contained in this document is accurate. However, EPM cannot be held responsible for any errors, omissions or inaccuracies, or any losses incurred as result of them.

IMPORTANT NOTICE

Because we are continuously improving our products, some of the menus which appear on your instrument’s display may not be exactly as illustrated and described in this manual. However, because the menus are simple and intuitive, this should not cause any major problems.

This manual is concurrent with embedded software version 552540, issue 4.30.00 (or higher)

Static precautions Some parts of the instrument (such as circuit boards) may be damaged by static electricity. Therefore, when carrying out any work which involves the risk of static damage to the instrument, the instructions show the following notice:

CAUTION

While carrying out this procedure, you must wear an earthed wrist strap at all times to protect the instrument against static shock.

At such times you must wear an earthed wrist-strap to protect the instrument.

Safety information NOTE: This information applies only to those instruments which are mains-powered.

Electricity is dangerous and you risk injury or death if you do not disconnect the power supplies before carrying out some of the procedures given in this manual. Whenever there is such a hazard, the instructions show a notice similar to the following:

WARNING

Electricity is dangerous and can kill. Disconnect all power supplies before proceeding.

You must heed any such warnings and make sure that, before you go any further:

All power leads are un-powered.

All power leads are disconnected from the equipment which you are working on unless the instructions tell you otherwise.

You obey any other common-sense precautions which may apply to your situation. If you obey these sensible precautions, you can work on the equipment in complete safety.

Battery-backed Memory notice It is essential that the Lithium Cell used for the battery backup is installed at all times (other than during

replacement). The 7955 Flow Computer will not power-up correctly if this battery is missing. If it is necessary to run the units without batteries for Intrinsic Safety reasons, then the battery should be replaced with a shorting disk inserted in the battery holder. Please consult the factory for further advice.

Replace the battery when the "Low Battery" system alarm is indicated. The procedure is in Chapter 14.

Contents

1. About this manual 1.1 1.1 What this manual tells you 1.1 1.2 Who should use this manual 1.1 1.3 Software versions covered by this manual 1.1

2. Getting started 2.1 2.1 What this chapter tells you 2.1 2.2 How to use this chapter 2.1 2.3 7955 Inputs 2.2

2.3.1 Overview 2.2 2.3.2 Flow Meter Connections 2.3 2.3.4 Density Transducers Connections (Safe Area Only) 2.5 2.3.5 Viscosity Transducer Connections 2.8 2.3.6 Temperature Transmitter Connections 2.10 2.3.7 Pressure Transmitter Connections 2.14 2.3.8 Digital Signal Input Connections 2.17

2.4 7955 Outputs 2.19 2.4.1 Overview 2.19 2.4.2 Mechanical Counter Connections 2.20 2.4.3 Chart Recorder Connections 2.21 2.4.4 Digital Signal Output Connections 2.22

2.5 Other 7955 Connections 2.23 2.6 Where to find the 7955 connectors 2.23

2.6.1 Pin designations for a 7955 without any option boards fitted 2.24 2.6.2 Pin designations for a 7955 with option board 79556 fitted 2.25 2.6.3 Pin designations for a 7955 with option board 79558 fitted 2.26 2.6.4 Pin designations for a 7955 with option board 79559 fitted 2.27

2.7 If you need help ... 2.28

3. About the 7955 3.1 3.1 Background 3.1 3.2 The 7955 Quad-Stream Liquid Flow Computer 3.1

3.2.1 Connection support 3.1 3.2.2 Application Feature List 3.2

3.3 Communications 3.4 3.4 Physical description of the 7955 3.4 3.5 Typical installation 3.5 3.6 Checking your software version 3.6

4. Installing the system 4.1 4.1 What this chapter tells you 4.1 4.2 Hazardous and non-hazardous environments 4.1 4.3 Installation procedure 4.1 4.4 Step 1: Drawing up a wiring schedule 4.1 4.5 Step 2: Unpacking the instrument 4.2 4.6 Step 3: Setting dip-switches 4.3 4.7 Step 4: Fitting the 7955 4.4 4.8 Step 5: Making the external connections 4.6 4.9 Step 6: Earthing the instrument 4.6 4.10 Step 7: Connecting the power supply 4.7

5. The keyboard, display and indicators 5.1 5.1 What this chapter tells you 5.1 5.2 The layout of the front panel 5.1 5.3 What the display shows 5.2 5.4 How the keys work 5.2 5.5 Using the keys to move around the menus 5.2 5.6 Using the keys to view stored data 5.3 5.7 Using the keys to edit information 5.4 5.8 The 7955 character set 5.7 5.9 LED indicators 5.7 5.10 Summary of key functions 5.8

6. The menu system 6.1 6.1 What this chapter tells you 6.1 6.2 What the menu system does 6.1 6.3 How the menu system works 6.1

7. Serial Communications and Networking 7.1 7.1 What this chapter tells you 7.1 7.2 7955 Communication capabilities 7.1

7.2.1 Communication ports 7.1 7.2.2 Data services 7.3

7.3 MODBUS from the 7955 view-point 7.4 7.3.1 Introduction 7.4 7.3.2 Supported MODBUS functions 7.4 7.3.3 Floating-point numbers 7.4 7.3.4 Word swap mode 7.4 7.3.5 MODBUS addressing 7.5

7.4 Connecting to Ethernet 7.6 7.5 Connecting to a 7955 Serial Port (RS-232 and RS-485) 7.7

7.5.1 RS-232 (full duplex) Rear Panel Pin Connections 7.7 7.5.2 RS-485 (half duplex) Rear Panel Connections 7.9

7.6 After Connecting up to the 7955 Serial Port … 7.10 7.6.1 General RS-232C/485 Port Configuration 7.10 7.6.2 RS-232 Configuration 7.10 7.6.3 RS-485 Configuration 7.11

7.7 After Connecting up to the 7955 Ethernet Port … 7.12 7.8 7955 Database access over a MODBUS network 7.14

7.8.1 Introduction 7.14 7.8.2 7955 Database Information: Software Parameter Values 7.16 7.8.3 7955 Database Information: Software Parameter Status 7.19 7.8.4 7955 Database Information: Size and Type of Software Parameter Value 7.21 7.8.5 7955 Database Information: Full Attributes of a Software Parameter 7.23

7.9 Historical Alarm logger access over a MODBUS network 7.24 7.9.1 Introduction 7.24 7.9.2 Worked examples 7.25

7.10 Historical Event logger access over a MODBUS network 7.31 7.10.1 Introduction 7.32 7.10.2 Worked examples

7.11 Archive access over a MODBUS network 7.37 7.11.1 Introduction 7.37 7.11.2 Worked examples 7.38

7A Addendum A: Peer-To-Peer Communications 7a.1 7B Addendum B: High-speed List Communications 7b.1 7C Addendum C: 16-bit Communications (Gould List) 7c.1 7D Addendum D: ‘Intelligent Transmitter’ Monitor 7d.1 7E Addendum E: Duty/Standby (Hot Back-up) 7e.1

8. Alarms and events 8.1

8.1 Alarms 8.1

8.1.1 Alarm types 8.1 8.1.2 Alarm indicators 8.1 8.1.3 How alarms are received and stored 8.2 8.1.4 Examining the Alarm Status Display and Historical Alarm Log 8.2 8.1.5 What the Alarm Status Display tells you 8.3 8.1.6 What the entries in the Historical Alarm Log tell you 8.3 8.1.7 Clearing all entries in the Historical Alarm Log 8.4 8.1.8 User-defined Alarms 8.4 8.1.9 Alarm Logger Output (ALO) 8.6 8.1.10 Alarm message list 8.7

8.2. Events 8.12

8.2.1 Introduction to 7955 events 8.12 8.2.2 Event indicators 8.12 8.2.3 How events are received and stored 8.12 8.2.4 Examining the Event Summary and the Event log 8.13

8.2.5 What the Event Status Display tells you 8.13 8.2.6 What the entries in the Historical Event Log tell you 8.13 8.2.7 Clearing all entries in the Historical Event Log 8.14

9. Additional facilities 9.1 9.1 Feature: Archiving 9.1

9.1.1 Introduction 9.1 9.1.2 Statistical information 9.2 9.1.3 Analysis of an archive 9.2 9.1.4 Configuration details 9.8 9.1.5 Re-sizing archive space 9.13 9.1.6 Operation details (Reporting) 9.14 9.1.7 Guided examples of archiving 9.17

9.2 Feature: PID Control 9.18 9.2.1 Overview 9.18 9.2.2 Configuration details 9.19

9.3 Selecting units and data formats 9.23 9.4 Parameter alarm limits 9.23 9.5 Fallback values and modes 9.24 9.6 Units which the 7955 can display 9.24

10. Configuring with Wizards 10.1 10.1 Introduction to Wizards 10.1 10.2 Using Wizards 10.1 10.3 Quick-view Guide ( Set-up Wizards ) 10.3 10.4 Units Wizard selection 10.6

11. Configuring without Wizards 11.1 11.1 What does this Chapter tell? 11.1 11.2 Quick-find Index 11.2 11.3 A structured approach to configuring 11.3 11.4 Reference page conventions 11.5 11.5 Analogue Inputs 11.6 11.6 Digital Inputs 11.7 11.7 Pulse Inputs 11.8 11.8 Turbine/Positive Displacement Flow 11.10 11.9 Orifice Flow Metering 11.17 11.10 Coriolis Flow Metering 11.29 11.11 Totalising (by metering-point) 11.32 11.12 Totalising (by Station) 11.34 11.13 Header ‘Density’ Temperature (1x4x1 Scheme) 11.35 11.14 Header ‘Viscosity’ Temperature (1x4x1 Scheme) 11.36 11.15 Meter-run Temperature (4x4x4 Scheme) 11.37 11.16 Header ‘Density’ Pressure (1x4x1 Scheme) 11.38 11.17 Metering Pressure 11.39 11.18 Header Density (1x4x1 Scheme) 11.40

11.19 API Referred Density (1x4x1 Scheme) 11.46 11.20 4x5 Matrix Referred Density (1x4x1 Scheme) 11.47 11.21 Known Fluid Density Referral (1x4x1 Scheme) 11.48 11.22 Metering density (4x4x4 Scheme) 11.50 11.23 Base density of known fluid 11.52 11.24 Specific gravity/Degrees API 11.53 11.25 Special equations 11.54 11.26 Header ‘Viscosity’ Density (1x4x1 Scheme) 11.55 11.27 Header Viscosity from 7827 (1x4x1 Scheme) 11.57 11.28 Viscosity Referral (1x4x1 Scheme) 11.60 11.29 Meter-run Viscosity (4x4x4 Scheme) 11.62 11.30 Base Sediment and Water Measurements 11.63 11.31 Net Oil/Water Measurements (1x4x1 Scheme) 11.65 11.32 Net Flow (by metering-point) 11.71 11.33 Net Flow (by Station) 11.73 11.34 Interface Detection 11.79 11.35 Live Analogue Outputs 11.83 11.36 Digital Outputs 11.84 11.37 Live Pulse Outputs 11.85 11.38 Passwords and Security 11.86 11.39 Multi-View Multi-Page 11.88

12. Routine operation 12.1 12.1 Viewing the data 12.1 12.2 Checking the performance of the 7955 12.9 12.3 Printed reports 12.11

13. Routine maintenance and fault-finding 13.1 13.1 Cleaning the instrument 13.1 13.2 Fault-finding 13.1

14. Removal and replacement of parts 14.1 14.1 Front panel assembly 14.1 14.2 Display 14.1 14.3 Switch panel 14.2 14.4 Processor board 14.3 14.5 Power supply board 14.3 14.6 Connector Board 14.3 14.7 Fuse 14.4 14.8 Back-up battery 14.5 14.9 Rear Panel Assembly 14.6 14.10 Mother Board 14.7 14.11 Guide to fitting the Ethernet board 14.8

15. Assembly drawing and parts list 15.1 15.1 What the drawing and parts list tells you 15.1 15.2 How to obtain spare parts 15.1

16A. Flow meter proving 16A.1 16A.1. Introduction to this Chapter 16A.1 16A.2 Provers and pipe proving methods 16A.2

16A.2.1 Flowmeter Provers 16A.2 16A.2.2 Uni-directional pipe prover 16A.2 16A.2.3 Bi-directional pipe prover 16A.5 16A.2.4 Brooks Compact (Small Volume) Pipe Prover 16A.8

16A.3 Double-time pulse interpolation 16A.10 16A.4 The Prover calculations 16A.11

16A.4.1 Volumetric Prover Proving of a Volumetric Meter (by Volume) 16A.11 16A.4 Volumetric Prover Proving of a Coriolis Mass Meter (by Mass/Vol.) 16A.14

16A.5 Connections: Inputs and Outputs 16A.16 16A.5.1 Status inputs 16A.16 16A.5.2 Status outputs 16A.21 16A.5.3 Analogue inputs 16A.26 16A.5.4 Pulse (Turbine) inputs 16A.26 16A.5.5 ‘Remote’ Proving connection summary 16A.26

16A.6 Valve control and monitoring 16A.27 16A.7 Configuration Tasks : Proving details 16A.32 16A.8 Operating a prove session 16A.45 16A.9 Archiving of proving information 16A.56 16A.10 Prover Reporting 16A.58 16A.11 Trouble-shooting guide 16A.60 16A.12 Miscellaneous Reference Information 16A.61

16B. Master Meter Proving 16B.1 16B.1 What is the purpose if this Chapter? 16B.1 16B.2 Master meter proving (with a 7955 multiple-run flow computer) 16B.1 16B.3 Master Meter Proving Calculations 16B.3

16B.3.1 Volumetric Master Meter Proving of a Volumetric Meter (for Volume) 16B.3 16B.3.2 Volumetric Master Meter Proving of a Coriolis Mass Meter (for Mass) 16B.5 16B.3.3 Coriolis Mass Master Meter Proving a Coriolis Mass Meter (by Mass) 16B.6 16B.3.4 Coriolis Mass Master Meter Proving a Volumetric Meter (by Volume) 16B.7

16B.4 Input and output connections for master metering 16B.8 16B.5 Configuration Tasks: Proving Details 16B.13 16B.6 Operating a Prove Session 16B.22 16B.7 Archiving of Proving Information 16B.24 16B.8 Prover reporting 16B.26

17. HART, SMART and the 7955 17.1 17.1 What this Chapter tells you 17.1 17.2 Introduction to SMART and HART with the 7955 17.1 17.3 Connecting the 7955 to a HART network loop 17.3

17.3.1 7955 Electrical connections and impedance requirements 17.3 17.3.2 Frequency-shift keying 17.4 17.3.3 Cable choice and the 65s rule 17.5

17.4 Configuring the 7955 to use a HART network loop 17.6 17.5 Post configuration - viewing HART data 17.8 17.6 SMART units of measurement 17.8

18. Batching (Transactions) 18.1 18.1 Standard batch operations 18.1

18.1.1 Batch operation types 18.1 18.1.2 Batch operation parameter reference 18.3 18.1.3 Guided Example 1: Manual batch type trigger 18.7 18.1.4 Guided Example 2: Timed batches 18.9 18.1.5 Guided Example 3: Product Zone Triggered Batches 18.11 18.1.6 Guided Example 4: Quantity batch with FDC – Single program loop 18.13 18.1.7 Guided Example 5: Quantity batch with FDC – Pause/resume 18.15 18.1.8 Printed Batch Reports 18.17

18.2 Retrospective batch total calculations 18.20 18.2.1 Overview 18.20 18.2.2 Using retrospective calculations (on an archived record) 18.21 18.2.3 Using retrospective calculations (on the current batch record) 18.23

19. Flow Computer Basic Language (FC-BASIC) 19.1 19.1 Introduction 19.1

19.1.1 What is FC-BASIC? 19.1 19.1.2 What can FC-BASIC be used for? 19.1 19.1.3 What needs to be configured on the 7955? 19.2

19.2 Editor commands 19.2 19.3 Command directory 19.3

19.3.1 Statements 19.3 19.3.2 Boolean operators 19.6 19.3.3 Logical and bitwise operators 19.6 19.3.4 Relational operators 19.6 19.3.5 Arithmetic operators 19.6 19.3.6 Arithmetic functions 19.6 19.3.7 Pre-defined arrays 19.7 19.3.8 Pre-defined constants 19.7 19.3.9 Variable types 19.7 19.3.10 Direct 7955 database access 19.7

19.4 Sample FC-BASIC scripts 19.8 19.4.1 Sample FC-BASIC script: Printed Report 19.8 19.4.2 Sample FC-BASIC script: Grab Sampler 19.9

Appendices

Appendix A Glossary A.1

Appendix B Blank wiring schedule B.1

Appendix C Technical data for the 7955 C.1

Appendix D Units and conversion factors D.1

Appendix E Data tables E.1

Appendix F Calculations F.1

Quick-start Guide

7955 2540 (QSTRT/AC) Page Q.1

Quick-start Guide

If you want to... Read....

• Find out what's in this manual Contents pages

• Get started quickly Chapter 2

• Get an overview of the instrument Chapter 3 and Appendix C

• Understand how the menu system works Chapter 6

• Make connections to the instrument Chapters 2, 4 and Appendix C

• Install the instrument and set it up Chapters 2, 4, 10 and 11

• Find out about Ethernet support Chapters 7 and 14

• Find out about proving support Chapters 16A and 16B

• Find out about HART support Chapter 17

• Find out about batching support Chapter 18

• Operate the instrument Chapters 5 - 9 and 12

• Carry out routine maintenance Chapter 13

• Trace and repair faults Chapters 13 and 14

• Remove and replace parts Chapters 14 and 15

• Understand what a term means Appendix A

Quick-start Guide

Page Q.2 7955 2540 (QSTRT/AC)

Chapter 1 About this manual

7955 (Ch01/CC) Page 1.1

1. About this manual

1.1 What this manual tells you This manual tells you how to install, configure, operate and service the instrument. In addition, some information is given to help you identify and correct some of the more common faults which may occur. However, since repairs are done by changing suspected faulty assemblies, fault-finding to board component level is not covered. This manual assumes that all devices or peripherals to be connected to the 7955 have their own documentation which tells you how to install and configure them. For this reason it is assumed that anything which you want to link to the 7955 is already installed and working correctly in accordance with the manufacturer’s instructions. Since the instrument can be used for a wide variety of purposes, it is driven by software specially for your application. This manual gives information about the software which applies to your machine only.

1.2 Who should use this manual This manual is for anyone who installs, uses, services or repairs the 7955.

1.3 Software version covered by this manual The software version dealt with in this manual is given on the title page. Chapter 3 tells you how to find out what software is installed in your instrument.

Chapter 1 About this manual

Page 1.2 7955 (Ch01/CC)

Chapter 2 Getting started

7955 2540 (CH02/AE) Page 2.1

2. Getting started

2.1 What this chapter tells you This chapter shows how to:

Connect different types of field transmitters to a 7955.

Set the DIP switches in the 7955.

Select the appropriate wizard to configure the 7955.

2.2 How to use this chapter This chapter is divided into distinct sections:

Section 2.3 - for 7955 Inputs only

Section 2.4 - for 7955 Outputs only

Section 2.5 - for Other 7955 Connections

Section 2.6 - for 7955 pin designation lists

These sections form a guide to the types of physical connection that the 7955 can support. For example, Section 2.3.4 features a liquid density transducer which uses the Period Time Inputs. Section 2.4.4 explains Status Outputs. Section 2.5 is different because it just points to dedicated chapters that deal with much more complex connections.

Worked examples are provided to assist both new users and advanced users. Each worked example has a comprehensive set of instructions to establish a successful physical connection. Instructions also show how to select the correct 7955 configuration wizard.

IMPORTANT NOTICE

Always refer to documentation supplied by the manufacturer for details of installing their equipment in a hazardous area. The 7955 is not intrinsically safe and can therefore only be used in a designated non-hazardous (safe) area.

Some types of connection may require DIP switches to be set. These switches are located inside the 7955. Worked examples only explain how to set a DIP switch. Newer models of the 7955 have DIP switch access holes on top of the housing. Older models require the removal of the housing.

Note that:

DIP switches which are not shown in the diagrams have no effect on the field transmitter shown.

Where a field transmitter can be connected to more than one input, the DIP switch setting depends on which input you have used.


Page 2.2 7955 2540 (CH02/AE)

2.3 7955 Inputs 2.3.1 Overview

The following sub-sections cover connections with external devices that provide only inputs to the 7955. Unless otherwise stated, information in this chapter is based on the software release that is concurrent with this operating manual. Use the “Health Check” facility on the 7955 to monitor what is being input. Refer to Chapter 13 to find out how to locate this facility using the 7955 menu system. Once located, select the particular type of input and then select the instance of that input to see what is happening.


7955 2540 (CH02/AE) Page 2.3

2.3.2 Flow Meter Connections Support is provided for connecting up to five Flow Meters:

A 7955 can accept either single or dual pulse trains from each Flow Meter. There are separate sets of

pins for each pulse train.

Each flow meter can be powered by using a specific set of pins on the 7955. These pins are an isolated supply source - 8V or 16V. These voltages are selectable by a changing single DIP switch inside the 7955. The DIP switch determines the voltage for all the Flow Meters powered by the 7955.

Example: A Turbine Flow Meter with dual pulse trains

Follow these instructions to work through the example:-

Turn off the power 1. Ensure that the 7955 is NOT powered up.

Set DIP switch

2. Select the voltage, 8V or 16V, that is required by all the Turbine Flow Meters. This diagram shows the 8V selection:

8V 16V

Connect the Turbine Flow Meter to the 7955

3. Wire the six flow meter connections to the 7955.

Each flow meter connection, shown in the diagram below, has a label. Use each label to reference the appropriate pin designation in Table 2.1). This table has pin designations for all possible turbine inputs on the 7955.

Powersupply unit

Pickup 'B'Turbine signal 'B' +

Turbine signal 'B' -

Turbine signal 'A' +

Turbine signal 'A' -

Pickup 'A'

Turbine Power +

Turbine Power -

Turbine

Figure 2.1: A typical dual pulse turbine flow meter with connections

Table 2.1: 7955 pin connections for a typical turbine flow meter

Connection label Pin Set #1 Pin Set #2 Pin Set #3 Pin Set #4 Pin Set #5 Turbine Power + SK3/4 SK3/4 SK3/4 SK3/4 SK3/4

Turbine Power - SK3/20 SK3/20 SK3/20 SK3/20 SK3/20

Turb. Signal ‘A’ + SK1/42 SK1/27 SK1/12 SK1/46 SK1/8

Turb. Signal ‘A’ - SK1/43 SK1/28 SK1/13 SK1/47 SK1/9

Turb. Signal ‘B’ + SK1/10 SK1/44 SK1/29 SK1/15 SK1/25

Turb. Signal ‘B’ - SK1/11 SK1/45 SK1/30 SK1/14 SK1/26


Page 2.4 7955 2540 (CH02/AE)

Important table notes

Flow Meters with only a single pulse train output should only use the connections associated with Pickup ‘A’. These are labelled in Table 2.1 (on page 2.3) as “Turb. Signal ‘A’ +” and “Turb Signal ‘A’ -”.

Application use of these turbine inputs will depend on the particular release of the software that is concurrent with this Operating Manual. Refer to Chapter 3 (About The 7955) or the 7955 configuration chapters for details on use of these inputs.

Turn on the power 4. Turn on the power to the system. The system goes through a Power On Self Test (POST) routine which takes less than 30 seconds. When it is finished, ignore any flashing alarm lights which may appear.

Go to the wizards menu 5. Press the MENU key to go to Page 1 of the Main Menu (if you aren’t there already).

6. Press the DOWN-ARROW key to go to Page 2 of the menu.

7. Press the c-key to select “Configure”.

8. Press the a-key twice to go to the wizards menu.

Select the wizard 9. Press the b-key then the UP-ARROW or DOWN-ARROW key to scroll through the option list until “Flow meter” is shown.

10. Press the b-key to select “Flow meter”.

11. Press the c-key to select “Turbine”.

Proceed with wizard 12. Refer to Chapter 10 for further guidance.


7955 2540 (CH02/AE) Page 2.5

2.3.3 Density Transducer Connections (SAFE AREA ONLY) Support is provided for connecting up to four Density Transducers:

A 7955 can accept frequency (periodic time) outputs from each Density Transducer. There are

separate sets of pins for four periodic time inputs.

Each Density Transducer can be powered by using a specific set of pins on the 7955. These pins utilise the 7955’s isolated power supply.

Example: A 783x/784x Density Transducer with integrated PT100 sensor

Follow these instructions to work through the example:


Density measurement connection

2. Wire the “Dens. Signal +” and “Dens. Signal -” connections to the 7955.

Each density connection, shown in the diagram below, has a label. Use each label to reference the appropriate pin designation in the top half of Table 2.2 (on page 2.6). This table has pin designations for all possible density inputs on the 7955.

Optional temperature measurement

3. Wire the PRT connections to the 7955.

Each PT100 connection, shown in the diagram below, has a label. Use each label to reference the appropriate pin designation in the bottom half of Table 2.2 (on page 2.6). This table has pin designations for all possible density inputs on the 7955.

Additional wiring 4. Additional wiring is required on the 7955 as follows :

(a) The chosen pin for “Dens. Signal -” must also be wired to ‘Density Power -” pin.

Note: “Density Power-” pin : Use SK3/19

(b) A resistor across two 7955 pins, “Dens. Power +” and “Dens. Signal +”.

Note: “Density Power+” pin : Use SK3/35

This schematic shows a 7955 wired up to a 783x/784x in this way:

330ohms

Dens.Power+

Dens. Signal -

Dens.Power -

Dens. Signal +1

2

783x/784x

Densitymeasurement

usingDensity input #1pins on a 7955

SK1/32

SK1/31

SK3/35

SK3/19

PT100THIS IS NOT USED

FOR THIS EXAMPLE

7955 (D-Type)


Page 2.6 7955 2540 (CH02/AE)

POS+ 1NEG- 2

34

56

PRT

78

910

1112

POS+ 1NEG- 2

34

56

PRT

78

910

1112

Dens. Signal +

Dens. Signal -

PRT Power +

PRT Signal +

PRT Signal -

PRT Power -

Figure 2.2: A 783x/784x Density Transducer with connections

Table 2.2: 7955 pin connections for a 783x/784x Density Transducer

Connection label Pin Set #1 Pin Set #2 Pin Set #3 Pin Set #4 Dens. Signal + SK1/31 SK1/48 SK1/16 SK1/33

Dens. Signal - SK1/32 SK1/49 SK1/17 SK1/50

PRT Power + SK3/49 SK3/16 SK3/31 SK3/13

PRT Signal + SK3/50 SK3/32 SK3/14 SK3/46

PRT Signal - SK3/33 SK3/15 SK3/47 SK3/29

PRT Power - SK3/17 SK3/48 SK3/30 SK3/45

Important notes

Application use of these density inputs will depend on the particular release of the software that is concurrent with this Operating Manual. Refer to Chapter 3 (About The 7955) or the 7955 configuration chapters for details on use of these inputs.

The sets of pins used by a Density Transducer are the same as those used for a Viscosity Transducer.

Installation of a 783x/784x in a hazardous area is not covered in this Operating Manual. Always refer to documentation supplied with the Transducer for this kind of information.


7955 2540 (CH02/AE) Page 2.7

Turn on the power

5. Turn on the power to the system. The system goes through a Power On Self Test (POST) routine which takes less than 30 seconds. When it is finished, ignore any flashing alarm lights which may appear.

Go to the wizards menu

6. Press the MENU key to go to Page 1 of the Main Menu (if you aren’t there already).




Select the wizard

10. Press the b-key then the UP-ARROW or DOWN-ARROW key to scroll through the option list until “Line density” is shown.

11. Press the b-key to select “Line density”.

Proceed with wizard

12. Refer to Chapter 10 for further guidance.


Page 2.8 7955 2540 (CH02/AE)

2.3.4 Viscosity Transducer Connections Support is provided for connecting up to four Viscosity Transducers:

A 7955 can accept frequency (periodic time) outputs from each Viscosity Transducer. There are

separate sets of pins for four periodic time inputs on the 7955.

Each Viscosity Transducer can be powered by using a specific set of pins on the 7955. These pins utilise the 7955’s isolated power supply.

Example: An EMC compliant 7827 Viscosity Transducer with integrated PT100 sensor



Viscosity measurement connection

2. Wire the “Signal +” and “Signal -” connections to the 7955.

Each 7827 connection, shown in Figure 2.3 on page 2.9, has a label. Use each label to reference the appropriate pin designation in the top half of Table 2.3 (on page 2.9). This table has pin designations for all possible inputs on the 7955.

Optional temperature measurement

3. Wire the PRT connections to the 7955.

Each PT100 connection, shown in the diagram below, has a label. Use each label to reference the appropriate pin designation in the bottom half of Table 2.3 (on page 2.9). This table has a set of pins for all possible density inputs on the 7955.

Additional wiring 4. Additional wiring is required on the 7955 as follows :

(a) Wire “Power -” to “Signal -”.

This schematic shows a 7955 wired up to a 7827 in this way:

Note:The "Sig -" connection on the 7827 is not shown since it is alreadyinternally linked to the "Supply -" connection. There is no need for anexternal link.

Signal -

PRT Signal -

PRT Signal +

PRT Power +

PRT Power -

Power -

Signal +

Power +Supply +

Sig +

Supply -

7827(EMC Compliant)

SK3/30

SK3/47

SK3/14

SK3/31

SK3/19

SK1/16

SK3/35

SK1/17

Density input #3pins on the 7955

PRT Input #3pins on the 7955

7955 (D-Type)

Integrated PT100(EMC Compliant)

PRT


7955 2540 (CH02/AE) Page 2.9

PRT Signal -

PRT Signal +Visc. Power +

PRT Power -

PRT Power +

+ - + -

Visc. Power -

Visc. Signal +

Visc. Signal -

Figure 2.3: An EMC compliant 7827 Viscosity Transducer with connections

Table 2.3: 7955 pin connections for a 7827 Viscosity Transducer

Connection label Pin Set #1 Pin Set #2 Pin Set #3 Pin Set #4 Signal + SK1/31 SK1/48 SK1/16 SK1/33

Signal - SK1/32 SK1/49 SK1/17 SK1/50

PRT Power + SK3/49 SK3/16 SK3/31 SK3/13

PRT Signal + SK3/50 SK3/32 SK3/14 SK3/46

PRT Signal - SK3/33 SK3/15 SK3/3/47 SK3/29

PRT Power - SK3/17 SK3/48 SK3/30 SK3/45

Important notes

Application use of these inputs will depend on the particular release of the software that is concurrent with this Operating Manual. Refer to Chapter 3 (About The 7955) or the 7955 configuration chapters for details on use of these inputs.

The sets of pins used by a Viscosity Transducer are the same as those used for a Density Transducer.

Installation of a 7827 in a hazardous area is not covered in this Operating Manual. Always refer to documentation supplied with the Transducer for this kind of information.

Turn on the power







Select the wizard

10. Press the b-key then the UP-ARROW or DOWN-ARROW key to scroll through the option list until “Viscosity” is shown.

11. Press the b-key to select “Viscosity”.

Proceed with wizard



Page 2.10 7955 2540 (CH02/AE)

2.3.5 Temperature Transmitter Connections Support is provided for sixteen Analogue Inputs. Loop powered type temperature transmitters may use any of the sixteen. However, PRT types (such as the PT100 sensor) are restricted to the first four. A maximum of six temperature field transmitters can connected at any one time.

IMPORTANT NOTICE

The 7955 pin designations for Analogue Inputs 14 can be seen named as PRT inputs in this manual. These particular pins have a dual purpose, PRT input or mA input. Setting a DIP switch determines the purpose.

mA-type Analogue Input

Care is needed when preparing to use a mA-type input (0-20mA or 4-20mA field transmitter):

Firstly, ensure that the DIP switch is set for mA input and not PRT input.

Secondly, ensure that only the Analogue power pins are used. The reason for this is that PRT power is only applied when a measurement of temperature is required and, therefore, not suitable for loop powered mA devices.

PRT-type Analogue Input

Care is needed when preparing to use a PRT-type input:

Firstly, ensure that the DIP switch is set for PRT input and not mA input.

Secondly, ensure that only the PRT power pins are used. The reason for this is that PRT power is only applied when a measurement of temperature is required and, therefore, not suitable for loop powered mA devices.

Example 1: How to connect a mA-type temperature transmitter



Set DIP switches 2. Select the Analogue Input to be used. The DIP switch needs to be set If this selection is any of the first four Analogue Inputs.

For example, if using Analogue Input #1, ensure that the DIP switches are set as shown here:

SW1

1

2

3

4

A

B

C

D

4-20mA PRT

1

2

3

4

A

B

C

D

SW2

Connect the temperature transmitter

3. Wire the connections to the 7955. Each connection, shown in the diagram on page 2.11, has a label. Use each label to reference the appropriate pin number in Table 4 (on page 2.11). This table has a set of pins for every analogue input on the 7955.


7955 2540 (CH02/AE) Page 2.11

+

-7955

AnaloguePower +

AnaloguePower -

Signal +

Signal -

Diagram 4: A mA-type temperature transmitter with connections

Note: Use this table in conjunction with Diagram 4 (on page 2.11):

Connection label AIN #1 AIN #2 AIN #3 AIN #4

Analogue Power+ SK3/34 SK3/34 SK3/34 SK3/34 Signal + SK3/50 SK3/32 SK3/14 SK3/46 Signal - SK3/33 SK3/15 SK3/47 SK3/29 Analogue Power- SK3/18 SK3/18 SK3/18 SK3/18

AIN #5 AIN #6 AIN #7 AIN #8



Analogue Power+ SK3/34 SK3/34 SK3/34 SK3/34 Signal + SK3/9 SK3/42 SK3/8 SK3/7 Signal - SK3/25 SK3/41 SK3/24 SK3/23 Analogue Power-

AIN #13 AIN #14 AIN #15 AIN #16


Table 4: 7955 pin connections for mA-type temperature transmitter

Important notes

AIN = Analogue Input. Application use of these analogue inputs will depend on the particular release of the software that is

concurrent with this Operating Manual. Refer to Chapter 3 (About The 7955) or the 7955 configuration chapters for details on use of these inputs.


Page 2.12 7955 2540 (CH02/AE)

Turn on the power 4. Turn on the power to the system. The system goes through a Power On Self

Test (POST) routine which takes less than 30 seconds. When it is finished, ignore any flashing alarm lights which may appear.






Select the wizard 9. Press the b-key then the UP-ARROW or DOWN-ARROW key to scroll through the option list until “Temperature” is shown.

10. Press the b-key to select “Temperature”.

Proceed with wizard 11. Refer to Chapter 10 for further guidance.


7955 2540 (CH02/AE) Page 2.13

Example 2: How to connect a PRT-type temperature transmitter to the 7955




For example, if using Analogue Input #1, ensure that the DIP switches are set as shown here:

SW1

1

2

3

4

A

B

C

D

4-20mA PRT

1

2

3

4

A

B

C

D

SW2

Connect the temperature transmitter

3. Wire the connections to the 7955.

Each connection, shown in the diagram on page 2.13, has a label. Use each label to reference the appropriate pin number in the table on page 2.13. This table has a set of pins for every PRT compatible analogue input on the 7955.

7955

PRTPower +

PRTPower -

PRTSignal +

PRTSignal -

Diagram 5: A PRT-type temperature transmitter with connections

Note: Use this table in conjunction with Diagram 5 (on page 2.13):

Connection label PRT #1 PRT #2 PRT #3 PRT #4

PRT Power + SK3/49 SK3/16 SK3/31 SK3/13 PRT Signal + SK3/50 SK3/32 SK3/14 SK3/46 PRT Signal - SK3/33 SK3/15 SK3/3/47 SK3/29 PRT Power - SK3/17 SK3/48 SK3/30 SK3/45

Table 5: 7955 pin connections for PRT-type temperature transmitter

Important notes

Only the first four Analogue Inputs can support PRT-type field transmitters.

Application use of these analogue inputs will depend on the particular release of the software that is concurrent with this Operating Manual. Refer to Chapter 3 (About The 7955) or the 7955 configuration chapters for details on use of these inputs.


Page 2.14 7955 2540 (CH02/AE)

2.3.6 Pressure Transmitter Connections Support is provided for sixteen Analogue Inputs. Loop powered type pressure transmitters may use any of the sixteen. A maximum of seven mA-type static pressure field transmitters can connected to the 7955 at any one time.

IMPORTANT NOTICE

The 7955 pin designations for Analogue Inputs 14 can be seen named as PRT inputs in this manual. These particular pins have a dual purpose, PRT input or mA input. Setting a DIP switch determines the purpose.

mA-type Analogue Input

Care is needed when preparing to use Analogue Inputs 14 with a mA-type (0/4-20mA) field transmitter:

Firstly, ensure that the DIP switch is set for mA input and not PRT input.

Secondly, ensure that only the Analogue power pins are used. The reason for this is that PRT power is only applied when a measurement of temperature is required and, therefore, not suitable for loop powered mA devices.

Analogue Inputs 516 are only suitable for mA-type (i.e. 0/4-20mA) field transmitters.

Example: How to connect a mA-type static pressure transmitter




For example, if using Analogue Input #1, ensure that the DIP switch is set as shown here:

SW1

1

2

3

4

A

B

C

D

4-20mA PRT

1

2

3

4

A

B

C

D

SW2

Connect the static pressure transmitter

3. Wire the connections to the 7955.

Each connection, shown in the diagram on page 2.15, has a label. Use each label to reference the appropriate pin number in Figure 2.4: (on page 2.15). This table has a set of pins for every analogue input on the 7955.


7955 2540 (CH02/AE) Page 2.15

+

-7955

AnaloguePower +

AnaloguePower -

Signal +

Signal -

Figure 2.4: A mA-type static pressure transmitter with connections

Table 2.4: 7955 pin connections for mA-type static pressure transmitter

Connection label AIN #1 AIN #2 AIN #3 AIN #4





Analogue Power+ SK3/34 SK3/34 SK3/34 SK3/34 Signal + SK3/9 SK3/42 SK3/8 SK3/7 Signal - SK3/25 SK3/41 SK3/24 SK3/23 Analogue Power-

AIN #13 AIN #14 AIN #15 AIN #16

Analogue Power+ SK3/34 SK3/34 SK3/ SK3/34 Signal + SK3/40 SK3/6 SK3/5 SK3/38 Signal - SK3/39 SK3/22 SK3/21 SK3/37 Analogue Power- SK3/18 SK3/18 SK3/18 SK3/18

Important notes

AIN = Analogue Input. “AIN #1” is Analogue Input One (Pin Set).

Application use of these analogue inputs will depend on the particular release of the software that is concurrent with this Operating Manual. Refer to Chapter 3 (About The 7955) or the 7955 configuration chapters for details on use of these inputs.


Page 2.16 7955 2540 (CH02/AE)

Turn on the power







Select the wizard

10. Press the b-key then the UP-ARROW or DOWN-ARROW key to scroll through the option list until “Pressure” is shown.

11. Press the b-key to select “Pressure”.

Proceed with wizard



7955 2540 (CH02/AE) Page 2.17

2.3.7 Digital Signal Input Connections There are 26 Status Inputs available on a 7955 without any option boards fitted. Two of them are special “fast” versions for use with a pipe based Flow Meter Prover. Appendix ‘C’ contains information about the number of extra Status Inputs on 7955 option boards.

The following diagrams show two methods for wiring up a Status Input:

1. Power usage (two options): (a) Internal powered

Status input

+5V to 24V(Isolated supply)

795x

0V (Isolated supply)

Status input common

Status input using internalvoltage source

3.3k

795x status input (Internal power) notes:

Always use an isolated voltage from therange 5V to 24V.

There are only a few isolated voltage pins,on the rear panel of the 795x, that aresuitable:

(a) Density power (24V)(b) Turbine power (8V or 16V)

Circuit operation notes:

A closed switch produces a digitalsignal that represents a value of 1

An open switch produces a digitalsignal that represents a value of 0

Isolated voltage supply pins

These are listed in the following table:

Choice Power source 7955 D-type (+24VDC)

7955 D-type (0VDC)

1 Density SK3/35 SK3/19 2 Density/Analogue SK3/36 SK3/20

(b) External powered (recommended): 795x status input (external power) notes:

1. Use a voltage that falls within the range 5V to 24V.

It is possible to use the same voltage source that is powering the 795x. In this case, the voltage requirement is 24V.

2. An isolated power source must be used to maintain status input isolation.

+5V to +24V(external)

Status input using externalvoltage source

Status input

795x

0V(external)

Status input common

3.3k

Circuit operation notes:

A closed switch produces a digitalsignal that represents a value of 1

An open switch produces a digitalsignal that represents a value of 0


Page 2.18 7955 2540 (CH02/AE)

2. Status input common pin

There are two pins to choose from:

Choice 7955 (D-type) 1 SK2/34 2 SK2/35

3. Status input signal pins

The functional responses from the 7955 are dependant on the particular release of the 7955 Application Software.

Software version 2540 does not have a default set-up for Status Inputs. Some configuring is necessary before Status Inputs are enabled. Since a majority are used by a Prover and there are numerous alternative layouts, functions and pin numbers are listed in Chapter 16.


7955 2540 (CH02/AE) Page 2.19

2.4 7955 Outputs 2.4.1 Overview

The following sub-sections cover connections with external devices that expect only outputs from the 7955. Unless otherwise stated, information in this chapter is based on the software release that is concurrent with this operating manual. Use the “Health Check” facility on the 7955 to monitor what is being output. Refer to Chapter 13 to find out how to locate this facility using the 7955 menu system. Once locate, select the particular type of output and then select the instance of that output to see what is happening.


Page 2.20 7955 2540 (CH02/AE)

2.4.2 Mechanical Counter Connections There are 5 Pulse Outputs available on a 7955 without any option boards fitted.

The following diagram shows the recommended method for wiring up a Pulse Output:

+5V to +40V

Pulse output +ve

Pulse output 1

0V

Relay

Pulse output common

Note:The +24V and 0V could betaken from a density supplyor somewhere else on theinstrument.

795X

All of the applicable pins are listed here: 1. Pulse output power+ pins

There is one suitable pin for all of the Pulse Outputs:

Choice 7955 (D-type)

1 SK1/7

2. Pulse output common pins

There is one suitable pin for all of the Pulse Outputs:


1 SK1/6

3. Pulse output pins

Pulse Output Default Allocation 7955 (D-type)

1 None SK1/23

2 None SK1/24

3 None SK1/39

4 None SK1/40

5 None SK1/41

Note: Refer to the configuration chapters for details on how to change the allocations


7955 2540 (CH02/AE) Page 2.21

2.4.3 Chart Recorder Connections There are 4 mA-type Analogue Outputs available on a 7955 without any option boards fitted.

The following diagram shows the recommended method for wiring up an Analogue Output:

Analogue OutputCommmon

795xAnalogue Output

Signal

All of the applicable pins are listed here: 1. Analogue output common pins

There is one suitable pin for all of the Analogue Outputs:


1 SK2/15 2. Analogue Output Pins

An.O/P Default Allocation 7955 (D-type)

1 None SK2/16

2 None SK2/17

3 None SK2/31

4 None SK2/32

5 None SK2/33

Note: Refer to the configuration chapters for details on how to change the allocations


Page 2.22 7955 2540 (CH02/AE)

2.4.4 Digital Signal Output Connections There are 25 Status Outputs available on a 7955 without any option boards fitted. Appendix ‘C’ contains information about the number of extra Status Outputs on 7955 option boards.

The following diagram shows the recommended method for wiring up a Status Output:

External power supply providesvoltage and current suitable foruser selected relay.

Status output

795x

Status output common

0V from external power supply

This diode protects 795xagainst reverse voltages

All of the applicable pins are listed here:

1. Status output common pin

There is one suitable pin:

Choice 7955 (D-type) Pin Number

1 SK2/14

2. Status output signal pin

The functional responses from the 7955 are dependant on the particular release of the 7955 Application Software.

Software version 2540 does have a default set-up for Status Outputs. However, some configuring is necessary before a majority of Status Outputs are enabled. The majority are used by a Prover and there are numerous alternative layouts. Therefore, most functions and pin numbers are listed in Chapter 16.

Status Output Default Function 7955 (D-Type)

Pin Number 1 Alarm Logger Output #1

2 Alarm Logger Output #2 SK2/12

3 Alarm Logger Output #3 SK2/13

4 User Alarm Output SK2/28


7955 2540 (CH02/AE) Page 2.23

2.5 Other 7955 Connections Serial Communications Turn to Chapter 7 for a full guide to Serial Communications involving the 7955. Pipe-based Flow Meter Prover Turn to Chapter 16 for a full guide to Flow Meter Proving with a 7955.

2.6 Where to find the 7955 connectors The connectors and pin designations referred to in this chapter can be found as follows:

Section 2.6.1 7955 pins without any option boards fitted

Section 2.6.2 7955 pins with option board 79556 fitted



Section 2.6.4 7955 pins with option board 79559 fitted Note: It is not possible for both option boards 79558 and 79559 to be fitted at the same time.

Note: See Appendix ‘C’ for a single combined list of all connectors and pin designations.

The 7955 Rear Panel


Page 2.24 7955 2540 (CH02/AE)

2.6.1 Pin designations for a 7955 without any option boards fitted. Note: This table is also valid with the HART option board (79557) fitted.

Pin SK1 SK2 SK3 SK4 SK5 SK6 PL1 1 Status o/p 12 Status i/p 1 Alarm common Ground

2 Status o/p 13 Status i/p 2 Alarm NC Comm 1 tx Ground

3 Status o/p 14 Alarm NO Comm 1 rx Supply -

4 Status o/p 15 Turbine power + Supply +

5 Status o/p com Status i/p 3 Analog i/p 15+ Comm 0V

6 Pulse o/p com Status i/p 4 Analog. i/p 14 +

7 Pulse o/p power Status i/p 5 Analog. i.p 12 + Comm 0V

8 Turbine Sig. 9 + Status i/p 6 Analog i/p 11 + Comm 3 rx/tx +

9 Turbine Sig. 9 - Status i/p 7 Analog. i/p 9 + Comm 3 rx

10 Turbine Sig. 2 + Status i/p 8 Analog. i/p 8 + Comm 3 rts

11 Turbine Sig. 2 - Status i/p 9 Analog. i/p 6 + Comm 2 rx/tx +

12 Turbine Sig. 5 + Status o/p 2 Analog. i/p 5 + Comm 2 rx

13 Turbine Sig. 5 - Status o/p 3 PRT 4 power + Comm 2 rts

14 Turbine Sig. 8 - Status o/p com PRT 3 signal +

15 Turbine Sig. 8 + Analog. o/p com PRT 2 signal -

16 Density Sig. 3 + Analog. o/p 1 PRT 2 power +

17 Density Sig. 3 - Analog. o/p 2 PRT 1 power -

18 Status o/p 16 Status i/p 10 0V Analogue

19 Status o/p 17 Status i/p 11 0V Density

20 Status o/p 18 Status i/p 12 0V Den./Ana./Turb. Comm 3 rx/tx -

21 Status o/p 19 Status i/p 13 Analog. i/p 15 - Comm 3 tx

22 Status o/p 20 Status i/p 14 Analog. i/p 14 - Comm 3 cts

23 Pulse o/p 1 Status i/p 15 Analog. i/p 12 - Comm 2 rx/tx -

24 Pulse o/p 2 Status i/p 16 Analog. i/p 11 - Comm 2 tx

25 Turbine Sig. 10+ Status i/p 17 Analog. i/p 9 - Comm 2 cts

26 Turbine Sig. 10- Status i/p 18 Analog. i/p 8 -

27 Turbine Sig. 3 + Status i/p 19 Analog. i/p 6 -

28 Turbine Sig. 3 - Status o/p 4 Analog. i/p 5 -

29 Turbine Sig. 6 + Status o/p 5 PRT 4 Signal -

30 Turbine Sig. 6 - Status o/p 6 PRT 3 Power -

31 Density Sig. 1 + Analog. o/p 3 PRT 3 Power +

32 Density Sig. 1 - Analog. o/p 4 PRT 2 Signal +

33 Density Sig. 4 + PRT 1 Signal -

34 Status o/p 21 Status i/p com +24V Analogue

35 Status o/p 22 Status i/p com +24V Density

36 Status o/p 23 Status i/p 20 +24V Dens./Ana.

37 Status o/p 24 Status i/p 21 Analog. i/p 16 -

38 Status o/p 25 Status i/p 22 Analog. i/p 16 +

39 Pulse o/p 3 Status i/p 23 Analog. i/p 13 -

40 Pulse o/p 4 Status i/p 24 Analog. i/p 13 +


42 Turbine Sig. 1 + Status i/p 26 Analog. i/p 10 +


44 Turbine Sig. 4 + Status o/p 8 Analog. i/p 7 +

45 Turbine Sig. 4 - Status o/p 9 PRT 4 power -

46 Turbine Sig. 7 + Status o/p 10 PRT 4 Signal +

47 Turbine Sig. 7 - Status o/p 11 PRT 3 Signal -

48 Density Sig. 2 + PRT 2 Power -

49 Density Sig. 2 - PRT 1 Power +

50 Density Sig. 4 - PRT 1 Signal +


7955 2540 (CH02/AE) Page 2.25

2.6.2 Pin designations for a 7955 with option board 79556 fitted

Pin SK1 SK2 SK3 SK4 SK5 SK6 PL1 1 Status o/p 12 Status i/p 1 Alarm common Ground

2 Status o/p 13 Status i/p 2 Alarm NC Comm 1 tx Ground

3 Status o/p 14 Alarm NO Comm 1 rx Supply -

4 Status o/p 15 Turbine power + Supply +

5 Status o/p com Status i/p 3 Analog i/p 15+ Comm 0V

6 Pulse o/p com Status i/p 4 Analog. i/p 14 +








14 Turbine Sig. 8 - Status o/p com PRT 3 signal +

15 Turbine Sig. 8 + Analog. o/p com PRT 2 signal -

16 Density Sig. 3 + Analog. o/p 1 PRT 2 power +

17 Density Sig. 3 - Analog. o/p 2 PRT 1 power -

18 Status o/p 16 Status i/p 10 0V Analogue

19 Status o/p 17 Status i/p 11 0V Density














33 Density Sig. 4 + Analog. o/p 5 PRT 1 Signal -















48 Density Sig. 2 + Analog. o/p 6 PRT 2 Power -

49 Density Sig. 2 - Analog. o/p 7 PRT 1 Power +



Page 2.26 7955 2540 (CH02/AE)


Pin SK1 SK2 SK3 SK4 SK5 SK6 PL1 1 Status o/p 12 Status i/p 1 Alarm common Comm 5 rx/tx + Ground

2 Status o/p 13 Status i/p 2 Alarm NC Comm 5 rx Comm 1 tx Ground

3 Status o/p 14 Status i/p 27 Alarm NO Comm 5 rts Comm 1 rx Supply -

4 Status o/p 15 Status i/p 28 Turbine power + Comm 4 rx/tx + Supply +

5 Status o/p com Status i/p 3 Analog i/p 15+ Comm 4 rx Comm 0V

6 Pulse o/p com Status i/p 4 Analog. i/p 14 + Comm 4 rts








14 Turbine Sig. 8 - Status o/p com PRT 3 signal + Comm 5 rx/tx -

15 Turbine Sig. 8 + Analog. o/p com PRT 2 signal - Comm 5 tx

16 Density Sig. 3 + Analog. o/p 1 PRT 2 power + Comm 5 cts

17 Density Sig. 3 - Analog. o/p 2 PRT 1 power - Comm 4 rx/tx -

18 Status o/p 16 Status i/p 10 0V Analogue Comm 4 tx

19 Status o/p 17 Status i/p 11 0V Density Comm 4 cts

































7955 2540 (CH02/AE) Page 2.27


Pin SK1 SK2 SK3 SK4 SK5 SK6 PL1 1 Status o/p 12 Status i/p 1 Alarm common Ethernet 0V Comm 5 rx/tx + Ground

2 Status o/p 13 Status i/p 2 Alarm NC Ethernet cd + Comm 5 rx Comm 1 tx Ground

3 Status o/p 14 Status i/p 27 Alarm NO Ethernet tx + Comm 5 rts Comm 1 rx Supply -

4 Status o/p 15 Status i/p 28 Turbine power + Ethernet 0V Comm 4 rx/tx + Supply +

5 Status o/p com Status i/p 3 Analog i/p 15+ Ethernet rx + Comm 4 rx Comm 0V

6 Pulse o/p com Status i/p 4 Analog. i/p 14 + Ethernet 0V Comm 4 rts


8 Turbine Sig. 9 + Status i/p 6 Analog i/p 11 + Ethernet 0V Comm 3 rx/tx +

9 Turbine Sig. 9 - Status i/p 7 Analog. i/p 9 + Ethernet cd - Comm 3 rx

10 Turbine Sig. 2 + Status i/p 8 Analog. i/p 8 + Ethernet tx - Comm 3 rts

11 Turbine Sig. 2 - Status i/p 9 Analog. i/p 6 + Ethernet 0V Comm 2 rx/tx +

12 Turbine Sig. 5 + Status o/p 2 Analog. i/p 5 + Ethernet rx - Comm 2 rx

13 Turbine Sig. 5 - Status o/p 3 PRT 4 power + + 12V Comm 2 rts

14 Turbine Sig. 8 - Status o/p com PRT 3 signal + Ethernet 0V Comm 5 rx/tx -






































Page 2.28 7955 2540 (CH02/AE)

2.7 If you need help... If you get into difficulties...

If you get into difficulties when using the wizards, you can abandon the configuration and start again as follows:

1. From the menu, keep selecting NO (usually by pressing the c-key) or, if that option is not available: 2. Press ENTER until you can start selecting NO. 3. Carry on with (1) and (2) until you return to the wizards menu where you started. 4. Start the worked example again. The configuration you abandoned is cleared from the instrument’s

memory when you begin again.

If you don’t know where the keys are...

Chapter 5 shows how to find all the keys referred to in the worked examples.

Chapter 3 About the 7955

7955 2540 (CH03/AF) Page 3.1

3. About the 7955

3.1 Background The 7955 is designed to meet the demand for a reliable, versatile, user-friendly and cost-effective instrument for flow metering. It has a Motorola 68332 32-bit microprocessor and surface-mounted circuit board components so that it is powerful, reliable and compact.

A 7955 features:

a maths co-processor (to improve calculation speed)

comprehensive I/O capabilities

alarms and alarm history facilities

a menu-driven, user-friendly interface (for easy access to information)

an IP50 case (when panel mounted)

dc powered

serial ports (using RS232 or RS485) for MODBUS network communications and printing

3.2 The 7955 Quad-Stream Liquid Flow Computer Software version 2540 has support for two pipeline layouts: 1x4x1 and 4x4x4.

The 1x4x1 Scheme In this scheme, there is a common input that splits into a maximum of four metering-runs (each with a Flow Meter) before re-combining to form a common output. There is an illustration of a 1x4x1 scheme on page 3.5.

The 4x4x4 Scheme In this scheme, there is a maximum of four independent metering-runs (each with a Flow Meter). There is an illustration on page 3.5.

3.2.1 Connection Support Supported Input Connections (1x4x1 scheme):

o 4 x Volumetric/mass flowmeters. (Quantity at Header: 0 ; Quantity at metering-runs: 4)

o 2 x Liquid Density Transducers. (Quantity at Header: 2 ; Quantity at metering-run: 0)

o 2 x Liquid Viscosity Transducers. (Quantity at Header: 2 ; Quantity at metering-run: 0)

o 7 x Temperature Field Transmitters. (Quantity at Header: 1 ; Quantity at each metering-run: 1 ; Quantity at Prover: 2)

o 7 x Static Pressure Field Transmitters. (Quantity at Header: 1 ; Quantity at each metering-run: 1; Quantity at Prover: 2)

o 1 x Master Meter or Pipe Prover (Uni-directional, Bi-directional or Brooks Compact)

o 1 x mA-type source - for Header Density ‘B’

o 1 x mA-type source - for Base Sediment and Water

o 4 x HART network loops (Maximum of 5 ‘SMART’ transmitters on each loop)

o Status Inputs for proving functions, detecting valve states, activating a print-out of a report, and selecting maintenance mode

Supported Output Connections (1x4x1 scheme):

o 5 x Pulse Outputs - for transmitting increments to totals

o 4 x Analogue Outputs (standard) - for controlling a Flow Control Valve at each metering-run

o 4 x Analogue Outputs (if an option board is fitted) - for transmitting values

o 1 x Master Meter Turbine or Pipe Prover (Uni-directional or Bi-directional)

o Status Outputs for proving functions, alarm logging and valve control


Page 3.2 7955 2540 (CH03/AF)

Supported Input Connections (4x4x4 scheme):

o 4 x Volumetric/mass flowmeters. (Quantity at metering-runs: 4)

o 4 x Liquid Density Transducers. (Quantity at metering-runs: 4) – valid if not using Viscosity Transducers

o 4 x Liquid Viscosity Transducers. (Quantity at each metering-run: 1) – valid if not using Density Transducers

o 6 x Temperature Field Transmitters. (Quantity at each metering-run: 1 ; Quantity at Prover Valves: 2)

o 6 x Static Pressure Field Transmitters. (Quantity at each metering-run: 1; Quantity at Prover Valves: 2)

o 1 x Master Meter or Pipe Prover (Uni-directional, Bi-directional or Brooks Compact)

o Status Inputs for proving functions, valve states, activating a print-out of a report and requesting maintenance mode

Supported Output Connections (4x4x4 scheme):

o 5 x Pulse Outputs - for transmitting increments to totals

o 4 x Analogue Outputs (standard) - for PID loop controlling a Flow Control Valve at each metering-run

o 4 x Analogue Outputs (if an option board is fitted) - for transmitting parameter values

o 1 x Master Meter Turbine or Pipe Prover (Uni-directional, Brooks Compact or Bi-directional)

o Status Outputs for proving functions, alarm logging and valve control

3.2.2 Application Feature List In this application, the main purpose of the 7955 is to calculate flow rates and flow (roll-over) totals for each metering-run (stream).

The following types are supported:

o Indicated Volume

o Gross Volume

o Indicated Standard Volume

o Gross Standard Volume

o Mass Station Flow Rates and Station Flow (Roll-over) Totals are also supported. The same types (as listed above) are supported but these involve the summation of metering-run values.

Also supported:-

Temperature Measurements

1x4x1 Scheme:

o ‘Density loop’ Temperature ‘A’ (direct from transmitter) o ‘Density loop’ Temperature ‘B’ (direct from transmitter) o Header ‘Density loop’ Temperature (direct from ‘A’ or ‘B’ measurement) o ‘Viscosity loop’ Temperature ‘A’ (direct from transmitter) o ‘Viscosity loop’ Temperature ‘B’ (direct from transmitter) o Header ‘Viscosity loop’ Temperature (direct from ‘A’ or ‘B’ measurement)

4x4x4 Scheme:

o Meter-run Temperature (direct from mA, RD/PT100 or HART transmitter)

Pressure Measurements

1x4x1 Scheme:

o Header ‘Density loop’ Pressure (direct from transmitter)

4x4x4 Scheme:

o Meter-run Pressure (direct from mA or HART transmitter)


7955 2540 (CH03/AF) Page 3.3

Viscosity Measurements

1x4x1 Scheme:

o Dynamic and Kinematic Viscosity ‘A’ (direct from a Viscosity Transducer) o Dynamic and Kinematic Viscosity ‘B’ (direct from a Viscosity Transducer) o Header Dynamic Viscosity (direct from ‘A’ or ‘B’ measurement) o Header Kinematic Viscosity (direct from ‘A’ or ‘B’ measurement) o Meter-run Viscosity (from API or 4x5 Matrix referral of Header Viscosity)

4x4x4 Scheme:

o Meter-run Viscosity (direct from a Viscosity Transducer) - Valid only if not requiring Meter-run Density measurements

Density Measurements

1x4x1 Scheme:

o Density ‘A’ (direct from a Transducer) o Density ‘B’ (direct from a Transducer) o Header Density (from ‘A’ or ‘B’ measurements)

o Metering-run Density (from API or 4x5 Matrix referral of Header Density) (Also gives CTL, CPL, Compressibility and Alpha)

4x4x4 Scheme:

o Metering-run Density (direct from a transducer) - valid only if not requiring Meter-run Viscosity measurements

Other Application Features:

o Base Sediment and Water at the Header (direct from a mA signal) - 1x4x1 Scheme only

o Base Density for each metering-run (from API or 4x5 Matrix referral) (Also gives CTLd, CPLd, Base Compressibility and Alpha)

o Specific Gravity for each metering-run (not a direct measurement)

o Degrees API for each Metering-run (not a direct measurement)

o Prover Inlet Temperature and Pressure (See Chapter 16)

o Prover Outlet Temperature and Pressure (See Chapter 16)

o Linearised ‘Meter Factor’ or ‘K-factor’ (for each Meter)

o CCF (Combined correction factor)

o VCF (Volume correction factor)

o Batching

o Interface detection (Product detection by density zones, Product Totalising)

o MODBUS and MODBUS/TCP Communications

o PID Controller (4 loops)

o Pipe Proving (with automatic or manual valve control and Prover report)

o Master Meter Proving (with automatic or manual valve control and Prover report)

o Data Archiving

o Net Oil and Net Water % Calculations and Totalisor

o Alarm summary and history log

o Event summary and history log

o Special Equation Type 1 (for each metering-run)

o Printed Reports

o Maintenance Mode


Page 3.4 7955 2540 (CH03/AF)

3.3 Communications The 7955 can operate as a MODBUS slave. It can:

download a configuration from a PC, DCS, etc

upload a configuration

monitor random locations in the 7955

interrogate the alarm and data logger buffers

manipulate the alarm and data logger buffers

set random locations with new data

instigate printed reports. Note: Chapter 7 contains a full guide to Serial Communications and Networking with the 7955.

3.4 Physical description of the 7955 The main body of the 7955 is a one-piece aluminium extrusion which provides the best possible EMC protection. The keyboard and display is attached to the front of the instrument and all electrical and communications connectors are mounted on the Rear Panel.

The standard 7955 contains four circuit boards. The Processor Board and the Power Supply Board are mounted horizontally. These are connected by plugs and sockets to the Mother Board which is mounted vertically at the back of the case. The Connector Board is parallel to the Mother Board to which it is joined.

The Keyboard and Display are wired to the Processor Board. The Connector Board holds the connectors to which external devices are linked.

Keyboardand display

Rear PanelConnectorBoard

PowerSupplyBoard

MotherBoard

ProcessorBoard

Pin 1

Pin 4

PL1

SK4

SK5

SK1

SK2

SK3SK6Pin 1

Pin 1Pin 1

Pin 1Pin 1

Pin 1Pin 15

Pin 25

Pin 9

Pin 50

Pin 50

Pin 50

The 7955 and its major assemblies


7955 2540 (CH03/AF) Page 3.5

An example of a 1x4x1 Scheme

(with optional Prover)

An example of a 4x4x4 Scheme

(with optional Prover)

3.5 Typical installations The diagrams below illustrate typical installations that can utilises a 7955 Flow Computer with software version 2540.

P TTH M

DP F F

TT

D

V

H M

DP F F

P TT

H M

DP F F

P TT

H M

DP F F

P TT

P MM

M

M

M

b

c

a

d

DENSITYBASE VISCOSITYLINE VISCOSITY

TEMPERATURE

1

2

10

2 34 5 67 8 9

CLR EXP

+/-

i


TEMPERATURE

DENSITYBASE VISCOSITYLINE VISCOSITYTEMPERATURE

851.57.56

52.75161.8

**

*

*

*

P TT DH M

DP F F

P TT DH M

DP F F

P TT DH M

DP F F

P TT DH M

DP F F

M M

M

M

M

M

M

M

b

c

a

d


TEMPERATURE

1

2

10

2 34 5 67 8 9

CLR EXP

+/-

i


TEMPERATURE

DENSITYBASE VISCOSITYLINE VISCOSITYTEMPERATURE

851.57.56

52.75161.8

FCV

FCV

FCV

FCV

Key to illustration

H Hand Operated Valve

M Motor Operated Valve (under 7955 control)

FCV Flow Control Valve (under optional PID control)

DP Differential Pressure Switch (using selected Digital Input)

F Flowmeter

P Pressure Sensor

T Temperature Sensor

D Density/Viscosity Transducer

Key to illustration

H Hand Operated Valve

M Motor Operated Valve (under 7955 control)

FCV Flow Control Valve (under optional PID control)

DP Differential Pressure Switch (using selected Digital Input)

F Flowmeter

P Pressure Sensor

T Temperature Sensor

D Density Transducer

V Viscosity Transducer

M * Motor Operated Valve driven as pairs by 7955


Page 3.6 7955 2540 (CH03/AF)

3.6 Checking your software version The 7955 is driven by pre-loaded software which differs according to the application for which the instrument is to be used.

PREFIX DIGIT 1 DIGIT 2 DIGIT 3 DIGIT 4

SOFTWARE VERSION NUMBER

DIGIT 2:

FLOW METER

0 NONE 1 ORIFICE 2 TURBINE/PD 3 VENTURI 4 MASS 5 MULTI

DIGIT 4:

SPECIAL 0 – 9

PREFIX:

HARDWARE PLATFORM

51 7951 55 7955

DIGIT 1:

METERED PRODUCT

1 GAS 2 LIQUID 3 BOTH 4 OTHER

DIGIT 3:

STREAMS/ CHANNELS 1 SINGLE 2 DUAL 3 TRIPLE 4 QUAD 5 1, 2, 3 or 4

For example, in the case of a 7955 Quad Stream Liquid Turbine Flow Computer the software configuration code is SW552540.

You can find the software configuration code in several ways:

1. It is printed on a label inside the instrument. You can find it by removing the terminal cover.

2. It is written into the menu structure.

Chapter 4 Installing the system

7955 (CH04/AB) Page 4.1

4. Installing the system

4.1 What this chapter tells you This chapter gives full instructions for installing the 7955.

It does not go into detail about how to install any peripheral devices (such as transducers, computers or printers) which are connected to the 7955. For this information you must refer to the documentation supplied with these items.

4.2 Hazardous and non-hazardous environments If all or part of an installation is in an area where there is the risk of fire or explosion (which is almost always the case when gases are involved), then safety barriers usually have to be wired into the circuit. However, some instruments (such as the Covimat) are explosion-proof and barriers are not, therefore, needed.

You must follow the manufacturers instructions and safety recommendations fully.

4.3 Installation procedure Briefly, the procedure is:

Step 1: Draw up a wiring schedule

Step 2: Unpack the 7955

Step 3: Set the DIP switches

Step 4: Fit the 7955

Step 5: Make all external connections

Step 6: Earth the installation

Step 7: Connect power supply

The steps in the procedure are explained in the following sections.

4.4 Step 1: Drawing up a wiring schedule Before you make any connections, you must draw up a wiring schedule to help you identify wiring colours and make sure that you do not connect more items of any given type than are allowed. (If you are in doubt, check the specification in Appendix C.)

A blank copy of a wiring schedule is given in Appendix B.


Page 4.2 7955 (CH04/AB)

4.5 Step 2: Unpacking the instrument Remove the instrument from its packing and examine it to see if any items are loose or if it has been damaged in transit. Check that all items on the shipping list are present. If any items are missing or if the equipment is damaged, contact your supplier immediately for further advice.

What should be supplied with the 7955:

Item Quantity

• Mounting Clamp Assembly 1

• Captive screws 2

• Mounting strap 1

• Location moulding 1

• 9-way D-type plug 1

• 9-way D-type connector hood 1

• 15-way D-type Free plug 1

• 15-way D-type hood 1


• 25-way D-type connector hood 1


• 50-way D-type hood 3

• 4-way socket 1

• Security label 2

• 1.6A fuse (this is a spare) 1

Note: If you have ordered optional, additional facilities (such as extra outputs) these are already installed in the machine.


7955 (CH04/AB) Page 4.3

4.6 Step 3: Setting DIP switches The 7955 has two blocks of DIP switches on the Processor Board, as shown in the diagram on the next page:

• SW1 switches select whether each input is 4-20 mA or PRT

• SW2 switches not used in the current version of 7955

Each switch in the SW2 block must be the same as the corresponding pair of switches in the SW1 block. The 7955 does not work correctly otherwise.

The 7955 is supplied with the DIP switches in these default settings:

• Turbine power: 8 VOLTS • Input 1 PRT • Inputs 2-4: 4-20mA

Part of the 7955Processor Board

1

2

3

A

B

C

4D

SW2

SW1

PRT4-20mA

DIP switches on the Processor Board of the 7955

If you want to change the DIP switch settings, you must also configure the inputs. This is explained in Chapter 10. Later models of 7955 have a small hole in the top of the instrument to allow access to the switches without removing the cover.

After the configuration has been completed (see Chapters 10 and 11), the 7955 should be switched into the 'secure' mode to prevent unauthorised or accidental tampering with the instrument's configuration.

Note: The 7955 is always shipped from the factory with the security lock on the front panel set to the ‘non-secure’ mode.


Page 4.4 7955 (CH04/AB)

4.7 Step 4: Fitting the 7955 Note: You must not fit the 7955 where it may be subjected to extreme conditions or be liable to

damage. For further information about the environmental conditions within which it can operate, see Appendix C.

1. Firstly, referring to this diagram, cut out an aperture in the front panel for each instrument which is to be mounted on it.

Minimum dimensions for a panel with apertures to fit four 7955's

Aperture for theinstrument



29±1mm

17±1mm

14.5mm

17.5mm192±1mm

96±1mm Aperture for theinstrument

2. Each instrument is mounted in a clamp which is fixed to the rear of the front panel, as shown in the two diagrams that follow.

MountingClamp

The 7955 unit

LocationMoulding

355mm

101mm

Panel withaperture

3mm

Before assembly


7955 (CH04/AB) Page 4.5

352mm12.5mm

7.2mm

10mm

3mm

CaptiveClamp

Screws (2)Rear Panel

of 7955

MountingClamp

113mm

221mm

Note: Sufficient clearance is required for plugs and cables at the rear of the 7955

After assembly

You can mount the clamp so that it is fixed permanently or can be removed later, if required. If you want the clamp to be fixed permanently, carry out Steps 3 - 8. If you want to be able to remove the clamp, carry out Steps 9 - 12.

If the clamp is to be fixed permanently: 3. Make sure that the face of the front panel is in good condition and has no loose or flaking

paint. Use a suitable de-greasing agent to clean the face of the panel.

4. Insert the location moulding through the aperture in the front panel.

5. Peel the protective strip off the adhesive tape on the face of the mounting clamp. Then, working from the back of the front panel, carefully position the clamp over the location moulding. The clamp and panel bond on contact.

6. Press firmly on the area where the clamp is bonded to the front panel to ensure that they are bonded firmly. Remove the Location Moulding and discard it.

7. Slide the instrument through the front panel. Tighten the two captive screws to secure it into the clamp.

Note that, if you install more than one instrument, it helps to support them if you use a Mounting Strap to link each clamp to the next one, as shown in the diagram:

Back ofinstrument

Back ofinstrument

Mountingstrap

Mounting clamp Mounting clamp

Inside offront panel

Mounting arrangements for more than one instrument

8. Finally, attach all connectors to the back panel.


Page 4.6 7955 (CH04/AB)

If the clamp is to be removable:

1. Insert the location moulding through the aperture in the front panel.

2. Working from the back of the front panel, carefully position the clamp over the location moulding. Remove the Location Moulding and discard it.

3. Slide the instrument through the front panel. Tighten the two captive screws to secure it into the clamp.

Note that, if you install more than one instrument, it helps to support them if you use a Mounting Strap to link each clamp to the next one, as shown in the diagram on the previous page..

4.8 Step 5: Making the external connections 1. Refer to the documentation supplied with the external equipment to see if you have to carry

out any special procedures when connecting them to the 7955. Take special notice of any information about safety requirements in hazardous areas, and complying with EMC regulations.

2. For each D-type connector, pass the connector hood over the cable and wire up the connector. Secure the hood and connector body together then connect the earth wire to the hood. Stick an identifying label on to the connector hood.

3. Check the wiring thoroughly against the schedule and wiring diagram.

4. Attach all connectors to the Back Panel.

Refer to Chapter 2 and Appendix C for examples of field transmitter connections and a full list of 7955 pin designations

4.9 Step 6: Earthing the instrument

NOTE: Incorrect earthing can cause many problems, so you must earth the chassis and the electronics correctly. However, the way in which you do this depends almost entirely on the type of installation you have and the conditions under which it operates. Therefore, because these instructions cannot cover every possible situation, the manufacturers recommend that earthing procedures should only be carried out by personnel who are skilled in such work.

The chassis of the 7955 must be earthed in all cases; both for safety reasons and to ensure that the installation complies with EMC regulations. Do this by connecting an earth lead from the stud on the rear panel to a local safety earth such as a cabinet earth or some other suitable metal structure.


7955 (CH04/AB) Page 4.7

Earthlead

Crinklewashers

Plainwashers

Nut

Thumbnut

Earthing the instrument chassis

In addition to earthing the chassis, you may have to make extra earth connections in some cases, depending on the installation requirements.

Details of this are given in Appendix C.

4.10 Step 7: Connecting the power supply Plug the dc power connector into plug PL2 and switch on the power.

The instrument goes through the following Power On Self Test (POST) routine:

• The display shows a sequence of characters or patterns to prove that all elements of the display are working. There is a pause of five seconds between each change of pattern.

• The program ROM is checked against a checksum. The display shows how the test is proceeding.

• Critical data are checked. The display shows the result of this check.

• The coefficients are checked. The display shows the result of this check.

• The battery-backed RAM is checked. The display indicates progress.

• Any saved programs are checked. The display shows the number of programs and their status. Note that, for a new machine, there are no stored programs.

• If a battery is fitted, its condition is checked and reported.

Note that, when the power is switched on, the alarms may light up. You can ignore these for the moment - alarms are explained later in this manual. You can now proceed to configure your 7955 (see Chapters 10 and 11).

If the POST fails to complete, switch off the power supply and check all connections and the DIP switch settings. Then re-connect the power supply. If the POST still fails to complete, switch off again and contact your supplier.


Page 4.8 7955 (CH04/AB)

Chapter 5 The keyboard, display and indicators

7955 (Ch05/EA) Page 5.1

5. The keyboard, display and indicators

5.1 What this chapter tells you This chapter tells you:

• How the front panel is laid out.

• What the buttons and indicators do.

• What characters you can display.

5.2 The layout of the front panel Figure 5.1 shows the layout of the keyboard. The diagrams at the end of this chapter give a visual summary of what each of the buttons do.

1. DOWN-ARROW 7. ENTER 13. PRINT MENU

2. UP-ARROW 8. INFORMATION MENU 14. STREAM/RUN SELECT

3. MULTI-VIEW DISPLAY 9. LIMIT ALARM LED 15. F1 (software specific function)

4. LEFT-ARROW 10. INPUT ALARM LED 16. SECURITY LED AND LOCK

5. RIGHT-ARROW 11. SYSTEM ALARM LED

6. BACK 12. MAIN MENU

Figure 5.1: The layout of the front panel


Page 5.2 7955 (Ch05/EA)

5.3 What the display shows The display can show the following information:

• Numerical data in floating point, exponent or integer formats • Text descriptors • Units of measurement (if applicable) • Status of parameters i.e. set, live, failed or fallback (if applicable) • Alarm and event information • Current time and date • Identification number (location ID) of parameter • Stream (metering-run) identification number (if applicable)

5.4 How the buttons work The buttons let you:

• Move around the menus.

• View data stored in the 7955 – VIEW mode.

• Edit the data – EDIT mode. Some buttons do different things according to where you are in the menu system. For example:

ENTER button This button does nothing until you get into EDIT mode. After you have

edited the data of a parameter, pressing ENTER accepts the changes and puts the 7955 back into VIEW mode.

c button When you move through the menu structure this selects any menu

choice shown against the button. However, when in VIEW mode, pressing c lists the display units.

INFORMATION MENU button

This button does nothing if you are in EDIT mode. At other times, it takes you to a special menu that provides information on alarms, events, flow status and 7955 operating mode.

PRINT MENU button

This button does nothing if you are in EDIT mode. At other times, it takes you to a special menu dealing with data archiving and printing of reports.

The sections that follow tell you more about what the buttons do and how you use them.

5.5 Using the buttons to move around the menus A general tour of the menu system is provided in chapter 6. The buttons, which you can use to move around the menu system, are:

UP-ARROW Moves the display up to the previous page of the menu. If there is no

previous page, this button does nothing.

DOWN-ARROW Moves the display down to the next page of the menu. If there is no

next page, this button does nothing.

:

a - d buttons Each of these buttons selects the menu choice next to it. If there is no menu choice next to a button, that button does nothing.

BACK Returns you to the previous step.


7955 (Ch05/EA) Page 5.3

MAIN MENU Moves you straight to page 1 of the top-level menu.

INFORMATION MENU

Takes you to a special menu providing information on alarms, events, flow status and 7955 operating mode.

PRINT MENU Takes you to a special menu dealing with data archiving and printing

of reports.

MULTI-VIEW You can define one or more display pages, each showing up to four

items of data, lines of descriptive text, or both. Pressing MULTI-VIEW shows the first display page you have defined. Use the up/down arrow buttons to page up and page down.

F1 The use of this button is dependent on the functionality of the

application software. If this button is in use, it will be mentioned in later chapters.

Note: All other buttons have no effect when moving around the menus.

5.6 Using the buttons to view stored data When a software parameter screen is viewed, after selection from the menu, the display is in VIEW mode.

Figure 5.2 shows a typical display when you view a software parameter screen. In VIEW mode, all information is in a right justified format.

Figure 5.2: A typical software parameter screen (in VIEW mode)

What the display shows

Line 1: Shows the parameter description. (Some words are abbreviated.)

Line 2: Shows the present value (or text for indirection type).

Line 3: Shows the measurement units (if any). This line is blank if there are no units.

Line 4:

The right-hand side shows LIVE, SET, FB (FALLBACK) or FAIL to indicate the state of the present value shown in Line 2, where appropriate. These indications mean:

LIVE – The data shown is live data received from the transducer/transmitter connected to the 7955 or calculated by the 7858 rather than a set value.

SET – There is a fixed value for the data; this value does not change unless you enter a new fixed value or make it live.

FB – A fallback or default value has been used to obtain the value for the data.

FAIL – The live input has failed, most likely due to no transducer/transmitter being connected or a calculation failed to complete due to incorrect configuration.

An alarm will be raised causing the Input Alarm LED to flash on the front panel. For troubleshooting this alarm, see chapter 8.

Optionally, Line 4 may also show the parameter’s unique identification number (location ID), which is required when setting up certain features e.g. Multi-view. You can toggle this information on/off by the ‘a’ button.


Page 5.4 7955 (Ch05/EA)

In VIEW mode, the buttons that you can use are:

‘a’ button On/off toggle for displaying the parameter’s unique identification number

(location ID). This is displayed to the left of the status indication on line 4.

‘b’ button Puts the 7955 into EDIT mode so that you can edit the data on line 2. The

data being edited is left justified whilst in EDIT mode. (See next section)

‘c’ button Puts the 7955 into EDIT mode so that you can select from a list of the units

in which the data can be displayed. The units are left justified whilst in EDIT mode. (See next section)

‘d’ button Puts the 7955 into EDIT mode so that you can select a status (Set or Live).

The status is left justified whilst in EDIT mode. (See next section)

STREAM / RUN SELECT

If there is more than one stream (metering-run) and there is a number on the far left of display line 4, this button will select another stream (metering-run). The screen will be refreshed with attributes (value, units and status) for that stream (metering-run).

BACK Returns you to the previous step.

MAIN MENU Takes you straight to page 1 of the top-level menu.

5.7 Using the buttons to edit information You can:

• Edit text

• Select an option from a multiple-choice list

• Edit numerical information

• Edit the date and time

5.7.1 Text editing Once in EDIT mode (see earlier), the buttons that you use to edit text are:

LEFT-ARROW Moves the cursor to the left, along the line of text you are editing.

RIGHT-ARROW Moves the cursor to the right, along the line of text you are editing.

UP-ARROW This button changes the character at the current cursor position. It scrolls

forwards through the alphanumeric character set. Stop when the character you want is displayed.

DOWN-ARROW Changes the character at the current cursor position. It scrolls

backwards through the alphanumeric character set. Stop when the character you want is displayed.

:

0 - 9 buttons Each button enters a single digit.

‘b’ button If you are satisfied with the changes you have made, press b to accept the

changes and go back to VIEW mode. (The ENTER button also does this.)


7955 (Ch05/EA) Page 5.5

ENTER If you are satisfied with the changes you have made, press ENTER to

accept the changes and go back to VIEW mode. (The ‘b’ also does this.)

CLEAR This clears a line of text.

BACK If you do not want to keep the changes you have made, press the BACK

button to abandon the changes and go back to VIEW mode.

PLUS / MINUS Toggles between lower and upper case letters.

5.7.2 Multiple-choice option selection Once in EDIT mode (see earlier), the keys that you use to select from a multiple-choice list are:

UP-ARROW Scrolls up through the available options.

DOWN-ARROW Scrolls down through the available options.

‘b’ button If editing the data (on display line 2) and you are satisfied with the

change you have made, press the ‘b’ to accept the change and go back to VIEW mode. (Note: The ENTER button also does this.)

‘c’ button If editing the measurement unit selection and you are satisfied with the

change you have made, press the ‘c’ to accept the change and go back to VIEW mode. (Note: The ENTER button also does this.)

‘d’ button If editing the status selection and you are satisfied with the change you

have made, press the ‘d’ to accept the change and go back to VIEW mode. (Note: The ENTER button also does this.)

ENTER If you are satisfied with the change you have made, press the ENTER

button to accept the change and go back to VIEW mode.

CLEAR Restore the previous contents.

BACK If you do not want to keep the changes you have made, press the

BACK button to abandon the changes and go back to VIEW mode.

5.7.3 Numerical editing Once in EDIT mode (see earlier), the buttons that you use to edit numerical data are:

LEFT-ARROW Erases the digit to the left of the cursor.

:


PLUS / MINUS This changes the sign of the number. Pressing it will toggle between

PLUS and MINUS signs.

DOT Inserts a decimal point.


Page 5.6 7955 (Ch05/EA)

EXPONENT Use this button if you want to show numbers in exponent form.

‘b’ button If you want to accept the changes you have made, press the ‘b’. The

7955 will then revert to VIEW mode. (Note: ENTER also does this.)

ENTER If you want to accept the changes you have made, press the ENTER key.

The 7955 will then revert to VIEW mode. (Note: ‘b’ also does this.)

CLEAR Clears the line you are currently editing.

BACK If you do not want to keep the changes you have made, press the BACK

button to abandon the changes and go back to VIEW mode.

Numerical entry When you type in a number the first digit appears at the left of the display and each successive digit is then positioned to the right of the one just entered. A number being entered over-types any existing number. Parameter identification number (Location ID) entry These appear on the display in the same way as for numerical entry. However, when you accept the number (by pressing ‘b’ or ENTER), the text descriptor of the parameter with that particular number appears on line 2. You will encounter this type of ‘pointer’ (indirection) editing if configuring the Multi-view display (see chapter 11).

5.7.4 Date and time editing

The date and time are displayed in the format: dd-mm-yyyy hh:mm:ss. When you edit the date and time, the cursor moves to the right but skips the ‘:’ and ‘-’ characters.

LEFT-ARROW Moves the cursor to the left.

RIGHT-ARROW Moves the cursor to the right.

:


‘b’ button If you want to accept the changes you have made, press ‘b’. The

7955 will then revert to VIEW mode. (Note: ENTER also does this.)

ENTER If you want to accept the changes you have made, press ENTER.

The 7955 will then revert to VIEW mode. (Note: ‘b’ also does this.)

CLEAR Restore the previous contents.

BACK If you do not want to keep the changes you have made, press the

BACK button to abandon the changes and go back to VIEW mode.

The new date and time is validated. An invalid date and time is causes the message “Bad date/time” to appear on-screen for a few seconds before the previous content is restored.


7955 (Ch05/EA) Page 5.7

5.8 The 7955 character set You can use any of the 96 characters shown below as part of your display.

Figure 5.3: The 7955 character set

5.9 LED indicators Security Indicator This LED shows the present security level of the system.

• RED FLASHING – The instrument is at Calibration level.

• RED – Engineer level: the instrument can be configured.

• ORANGE – Operator level: limits can be changed.

• GREEN – World level: no parameters can be changed.

Note: For more information about these, see Chapter 11.

1. Security Level LED.

Figure 5.4: Alarm Indicators

Alarm Indicators These are the Input, System and Limit alarms. For more information about

these, refer to Chapter 8: “Alarms and Events”.

1. System alarm LED. 2. Input alarm LED. 3. Limit alarm LED.

Figure 5.5: Alarm Indicators


Page 5.8 7955 (Ch05/EA)

5.10 Summary of button functions The tables here provide a visual summary of the function for each button when in various modes.

Table 5.1: Summary of what the buttons do (Part 1 of 2)


7955 (Ch05/EA) Page 5.9

Table 5.2: Summary of what the buttons do (Part 2 of 2)


Page 5.10 7955 (Ch05/EA)

Chapter 6 The menu system

7955 (Ch06/GA) Page 6.1

6. The menu system

6.1 What this chapter tells you Before you can configure and operate the 7955, you should have some understanding of how the menu system works. The menus are simple and intuitive, so they should present no problems to the average user. This chapter gives you a general tour, showing how to navigate the menu system to find application parameter screens and other types of screen such as for entering passwords.

Note: The menus will differ between software versions, and can differ between releases of a software version.

Chapter 12 features tables showing the routinely used (operator) parts of the menu system used in your software.

6.2 What the menu system does The menu system lets you:

• Configure the 7955.

• Operate it.

• View data and settings stored in the 7955.

• Edit data stored in the 7955.

6.3 How the menu system works When you power-on the 7955, the menu system appears immediately after the routine Power-On-Self-Test (POST) is completed. If it is the first power-on since the software was installed, a screen appears showing the software version number and the issue number. if this is not the case, the screen will be the last visited menu location prior to powering off (or a power failure). Press the MAIN MENU button once and page 1 of the top-level menu will appear (see Figure 6.1). The menu system is a tree-like structure that repeatedly branches to lower levels until a final screen is reached. Page 1 of a top-level menu shown in Figure 6.1. It comprises four menu choices – Flow rates, Flow totals, Density and Viscosity. Each menu choice has a description e.g. “Flow rates” and a triangular icon e.g. alongside to indicate the type of menu choice. A non-filled, triangular icon ( ) indicates the menu choice leads to a lower-level menu (sub-menu). A filled, triangular icon ( ) indicates the menu choice leads to a non-menu screen.

Note: The menus may be different in your software.

Figure 6.1: page 1 of a top-level menu


Page 6.2 7955 (Ch06/GA)

Each menu choice is associated by position with a lettered button on the front panel - a, b, c or d. For example, a menu choice on Display Line 1 is associated with the a button. Similarly, a menu choice on Display Line 2 is associated with the b button, and so on. If there is no menu choice on a display line, the associated letter button will not do anything. When you do make a menu choice from a menu using the lettered buttons, the display changes to show the selected lower-level menu or a non-menu screen. Figure 6.2 shows an example where pressing the a button will lead to a lower-level menu for “Flow rates”. Similarly, the b button leads to a lower-level menu for “Flow totals”. Using the BACK button will return you to the previous menu level, which, in this example, is the top-level menu shown in the middle.


Figure 6.2: Menu Choice Selection

Where a menu has more choices than can fit on to the 4-line display, the menu comprises of two or more pages. Vertical arrow icons appear on the left-hand side of display to indicate there are further pages on the same menu level. Figure 6.3 shows how you can scroll up or down between the pages by using the UP-ARROW and DOWN-ARROW buttons. These buttons will do nothing if there is no page to scroll to.


Figure 6.3: Pages of a Main Menu


7955 (Ch06/GA) Page 6.3

At the lowest levels in each branch of the menu system, there are parameter screens. Figure 6.4 shows how to navigate to the parameter screen for <MeterRun Temperature>. All parameter screens feature a solid, black, triangular shaped mark in the bottom-left corner of Display Line 4. Note: Full details about editing parameters can be found in Chapter 5.


Figure 6.4: A typical software parameter screen Returning to the top-level menu again, there are menu choices that are common to all software versions (Figure 6.5). In addition, you’ll encounter them in subsequent chapters. All other menu choices on the Main Menu (e.g. “Flow rates”) are for operators to quickly find final measurements and other calculation results. Chapter 12 has tables showing these menus in more detail.

Figure 6.5: Menus common to all software versions

Leads to a screen for entering a password to change security level. (See Chapter 11).

Leads to menus for viewing interim results of measurements and other

calculations, Inputs, Outputs, etc. (See Chapter 12 for a full map)

Leads to menus for editing measurement tasks for your installation. (See Chapters 7 - 11).


Page 6.4 7955 (Ch06/GA)

Chapter 7 Serial Port Communications and Networking

7955 2540 (CH07/BC) Page 7.1

7. Serial Port Communications and Networking

7.1 What this Chapter tells you This chapter is a comprehensive guide to serial RS-232/485 and Ethernet port communications with the 7955. Since this subject area is vast, with countless reference books, the scope is restricted to the 7955 point-of-view. Therefore, it has been assumed that the reader has a reasonable working knowledge of data communications and networking.

Highly recommended references for this Chapter are:

The 1992 edition of “MODICON MODBUS PROTOCOL REFERENCE GUIDE (PL_MBUS-300)”. Release 1.0 of the “OPEN MODBUS/TCP SPECIFICATION” (available from www.modicon.com)

Note: This Chapter is not a guide to the MODBUS and MODBUS/TCP protocols

7.2 7955 Communication Capabilities The 7955 has extensive facilities – ports and data services – to allow the communication of data with almost any device that has support for the Modicon MODBUS and MODBUS/TCP protocol.

Communication ports and their associated standards are summarised in Table 7.1. Various application data services are available through the ports and are introduced in Section 7.2.2.

Table 7.1: 7955 Communications Ports and Supported Standards

Serial Port One *

Serial Port Two *

Serial Port Three *

Serial Port Four **

Serial Port Five **

Ethernet Port One ***

RS-232C RS-232C/485 RS-232C/485 RS-232C/485 RS-232C/485 IEEE 802.3

MODBUS MODBUS MODBUS MODBUS MODBUS MODBUS/TCP

* Fitted as standard ** Requires option board 79550508 or board 79550509 to be fitted

*** Requires option board 79550509 to be fitted

7.2.1 Communication Ports Serial RS-232/485 Ports Two serial interface standards are supported by the 7955 – Serial RS-232C (full duplex) and Serial RS-485 (half duplex). They are software selectable if there is a choice for a particular port.

RS-232C is the usual choice for a direct (point-to-point) network connection with only one device. Typically, it is utilised when transmitting printed reports to an ASCII compatible output device, such as a printer or a terminal. Another main use is the ‘Peer-to-Peer List’ data service that can regularly broadcast parameter values to another 7955 instrument. Data services are introduced in Section 7.2.2.

RS-485 is the choice when establishing a multi-drop network with two or more devices. This network allows both Master/Slave and Peer/Peer arrangements of devices and, subsequently, full availability of all data services. Data services are introduced in Section 7.2.2.

Ethernet Port An Ethernet port becomes available when add-on board 795505092 is fitted inside the 7955, as guided in Chapter 14. However, you will first need to check that the firmware (software version) release you intend to use does feature Ethernet functionality. Secondly, a 10Mbits/s MAU – Media Access Unit - adapter must be attached to a 15-pin D-type socket on the rear panel (see Section 7.4 on page 7.6). The 10 BaseT (10Mbit/s) Ethernet port is compliant with the IEEE 802.3 standard for TCP/IP3. This connectivity option allows you attach 7955 Flow Computers to any local or wide area network that is using the TCP/IP protocol.

2 When ordering the Ethernet pack containing the add-on (option) board, use part number 79559. 3 TCP/IP is the abbreviation for “Transport Control Protocol/Internet Protocol”, which is a suite of communications protocols.


Page 7.2 7955 2540 (CH07/BC)

For connection to 100Mbit/s (or higher speed) Ethernet networks, you can connect the 7955 instrument to a communication hub for the conversion from 10Mbit/s. However, this speed is very misleading. In practice, average data transfer rates will be much lower – roughly 9600bps – and stretch machine cycle times as indicated in Table 7.2 and Table 7.3. The 7955 can be configured to function as an Ethernet Server, an Ethernet Client, or both. When the 7955 is functioning as an Ethernet Server it can have concurrent connections (channels) with up to two registered (known) clients. Registered clients must be MODBUS TCP/IP compliant devices, such as other 7955 instruments, so that they can access the data services available on the 7955 Ethernet Server. When the 7955 is functioning as an Ethernet Client and it is registered with a 7955 Ethernet Server, it can use the ‘Peer-to-Peer Lists’ to communicate parameter values/settings with that Server. Similarly, this Client/Server set-up can be used by remote meter proving functions. (Proving is explained in Chapter 16) All data services are introduced in Section 7.2.2.

Table 7.2: Times for High Speed List Read Operations

Data Read Cycle Time Change

10 floating-point numbers + 200ms


30 floating-point numbers +600ms

Table 7.3: Times for High Speed List Write Operations

Data Written Cycle Time Change


20 floating-point numbers + 1.5s

30 floating-point numbers +2.0s


7955 2540 (CH07/BC) Page 7.3

7.2.2 Data Services Identical data services are available through the Ethernet port and any serial RS232/485 port. However, the availability of a service does depend on Master/Slave and Client/Server arrangements.

Services are accessed by a half-duplex exchange of MODBUS (or MODBUS/TCP) – request and response - messages between the 7955 instrument and another MODBUS (or MODBUS/TCP) device. Guided examples with the necessary message sequences to correctly access services are given later in Chapter 7 and in any extra pages that are inserted between Chapters 7 and 8.

Table 7.4: Data Services Availability (Master/Slave)

Data Services Available on Master/Slave Purpose of Data Service

Database Access 7955 Slave Allow any (non-7955) MODBUS Master device to perform read/writes on an individual parameter in the database of a Slave

Historical Alarm Log 7955 Slave Retrieval of LIVE alarm information from the Historical Alarm Log. (Events are explained in Chapter 8 of this manual)

Historical Event Log 7955 Slave Retrieval of LIVE event information from the Historical Event Log. (Alarms are explained in Chapter 8 of this manual)

High Speed List 1 * 7955 Slave Allow non-7955 MODBUS Master device to perform fast read/writes on an arranged group of up to 150 parameters.

High Speed List 2 * 7955 Slave Allow non-7955 MODBUS Master device to perform fast read/writes on an arranged group of up to 150 parameters.

Archive Access 7955 Slave Retrieval of software parameter data from any of the data archives. (Archiving is explained in Chapter 9 of this manual)

Peer-to-Peer * 7955 Master Allow 7955 MODBUS Master to perform read/writes on software parameters in the database of multiple 7955 MOBUS slaves

* This application data service is fully explained in the extra pages between Chapter 7 and Chapter 8

Table 7.5: Data Services Availability (Ethernet Client/Server)

Data Services Available on Client/Server Purpose of Data Service

Database Access 7955 Server Allow Ethernet Clients to perform read/write operations on an individual software parameter in the database of the Server

Historical Alarm Log 7955 Server Retrieval of LIVE alarm information from the Historical Alarm Log. (Events are explained in Chapter 8 of this manual)

Historical Event Log 7955 Server Retrieval of LIVE event information from the Historical Event Log. (Alarms are explained in Chapter 8 of this manual)

High Speed List 1 * 7955 Server Allow Ethernet Clients to perform fast read/writes on an arranged group of up to 150 software parameters. (Independent of HSL-2)

High Speed List 2 * 7955 Server Allow Ethernet Client to perform fast read/writes on an arranged group of up to 150 software parameters. (Independent of HSL-1)

Archive Access 7955 Server Retrieval of software parameter data from any of the data archives. (Archiving is explained in Chapter 9 of this manual)

Peer-to-Peer * 7955 Client Allow 7955 Ethernet Client to perform read/writes on software parameters in the database of a 7955 Ethernet Server

* This application data service is fully explained in the extra pages between Chapter 7 and Chapter 8


Page 7.4 7955 2540 (CH07/BC)

7.3 MODBUS from the 7955 view-point

7.3.1 Introduction The Modicon MODBUS specification is designed to transfer data in 1-bit (coil) or 16-bit (register) blocks. This protocol has not been designed to deal with data, such as floating point numbers, which require a minimum of 32-bit blocks. For this reason, every manufacturer of computer equipment, which deals with this type of data, must decide in which way the protocol should be extended. Consequently, many different implementations exist for the transfer of 32-bit floating-point data.

7.3.2 Supported MODBUS Functions The 7955 supports three MODBUS functions:

1. Function 03 – Read multiple registers

2. Function 06 – Write single register

3. Function 16 – Write multiple registers

Data stored within a 7955 is represented by one or more 16-bit registers. Where registers contain a collection of bits, the 16-bit register is still used rather than individual bit (coil) access.

The 7955 supports both single and multiple register access. Each port is configured individually to allow one type of register access. Multiple Register Access: ‘write’ command involving a 21-byte character string will specify 11 registers.

Single Register Access: ‘write’ command involving the same character string will specify just 1 register.

7.3.3 Floating Point Numbers Floating-point values within the software parameter database are stored as 64-bit IEEE (double-precision) numbers. When requested over a MODBUS network link, a floating-point value is either encoded as a 32-bit IEEE (single-precision) number or encoded as a 64-bit IEEE (double-precision) number. The precision level is individually selectable for each communication port.

7.3.4 Word Swap Mode Since Modicon did not define 32-bit data transfers, the order of transmission for (2 x 16-bit) words of a 32-bit value is also not defined. The 7955 therefore provides the facility to choose whether the first or second word is the most significant. For 64-bit numbers, word swap places the second double-word as the most significant. This mode is individually selectable for each port.

Figure 7.1: Word Ordering Examples

WORD '1'(16 Bits)

WORD '2'(16 Bits)Default Order

Word Swap

42 C2 3F 0D

WORD '1'(16 Bits)

WORD '2'(16 Bits)

42 C23F 0D

SINGLE PRECISION

WORD '1'(16 Bits)


Word Swap

40 58 47 E1

WORD '3'(16 Bits)

WORD '4'(16 Bits)

9B 90EA 9E

DOUBLE PRECISION

WORD '3'(16 Bits)

WORD '4'(16 Bits)

9B 90 EA 9E

WORD '2'(16 Bits)

WORD '1'(16 Bits)

47 E1 40 58


7955 2540 (CH07/BC) Page 7.5

7.3.5 MODBUS Addressing Unlike most MODBUS devices, the 7955 instrument can respond to more than one MODBUS address through a communication port. MODBUS Slave

The base address of a MODBUS Slave is programmable and is used for accessing the database of software parameters. It is also possible to configure a 7955 to allow access to further data services through virtual addressing – consecutive MODBUS addresses offset beyond the base address. MODBUS/TCP Server

The unit identifier (base address) of a MODBUS/TCP Server is programmable and is used for accessing the database of software parameters. It is also possible to configure a 7955 Ethernet Client to allow access to further data services through virtual addressing – consecutive MODBUS addresses offset beyond the base address. You do not need to edit these virtual addresses because they are at fixed offsets beyond the programmed base address. The offsets are illustrated in Table 7.6. A virtual address becomes active when the corresponding data service is enabled. Note: There can be different base addresses programmed for each individual port if you require it.

However, the fixed address offsets still apply and will access exactly the same data service.

Table 7.6: Data Services and MODBUS Addressing

MODBUS Addressing Data Service Address Offset Base address Software Parameter Database +0

(Base address) Peer-to-Peer Lists (+0)

Virtual Address ‘1’ Historical Alarm & Event Log +1

Virtual Address ‘2’ High Speed List ‘1 +2

Virtual Address ‘3’ High Speed List ‘2’ +3

Virtual Address ‘4’ Data Archives +4

Note: ‘Peer-to-Peer List’ functions use the ‘Software Parameter Database’ service of a 7955 MODBUS Slave/Ethernet Server


Page 7.6 7955 2540 (CH07/BC)

7.4 Connecting to Ethernet The Ethernet port terminals are exclusively on the rear panel 15-pin D-type socket labelled SK4. Appendix C has a table listing the individual terminals.

Unlike the serial RS-232C/485 ports on the 7955, an Ethernet network must never be wired directly to this Ethernet port. Direct wiring prevents the 7955 instrument from being electrically isolated. Instead, a MAU (transceiver) device must be attached to socket SK4 and the Ethernet cable is then attached to the MAU. This can be seen in Figure 7.4.2 Since the MAU will usually not have attachment screws, it is held in place with a slide-lock mechanism that is already integrated into socket SK44. Once the MAU device is engaged with the socket, the slide-lock is adjusted to hold it firmly in place. Depending on the make and model of the MAU device, there will be ports for the various Ethernet plug-in connectors used by different cable types. Figure 7.4.1 shows a typical MAU that can be ordered with or without the Ethernet add-on board. This particular device has a port for a RJ45 connector, which is common for twisted-pair Ethernet cabling. After successfully connecting the 7955 Flow Computer to the Ethernet network, the next stage is to configure the communication parameters. This information is in Section 7.7 on page 7.12.

Figure 7.4.1: A typical MAU device

Figure 7.4.2: Where to attach to MAU adapter

4 Older rear panels have a SK4 socket without an integrated slide-lock mechanism. Flow Computers can be upgraded at our factory.


7955 2540 (CH07/BC) Page 7.7

7.5 Connecting to a 7955 Serial Port (RS-232 and RS-485) This Section is a reference with a table of grouped rear panel pins for each serial port.

7.5.1 RS-232 (full duplex) Rear Panel Pin Connections

RS-232C Serial Interface Pin Groups (Serial Port ‘1’)

7955 (D-type) Function Comm 1 Tx SK6/02 Transmit data

Comm 1 Rx SK6/03 Receive data

Comm 0V SK6/05 0V GND (Signal Ground)





Comm 2 CTS SK5/25 Clear to send

Comm 2 RTS SK5/13 Request to send













Note: This optional serial port is available when add-on board 79558 is installed inside the 7955

RS-232C Serial Interface Pin Group (Serial Port ‘5’)






Note: This optional serial port is available when add-on board 79558 is installed inside the 7955


Page 7.8 7955 2540 (CH07/BC)

A simple network can consist of just two devices. They could be an IBM compatible PC and a 7955 connected by a RS-232C ‘straight through’ cable.

Tx

Rx

Rx

Signal Ground

Tx2

5

3

7955

SK6/2

SK6/3

SK6/5

PC

PC com port connection to 7955 port 1RS-232 wiring with no RTS/CTS handshaking

CTS

7955

Tx

Rx

Rx

Signal Ground

Tx2

5

3

SK5/24

SK5/12

SK5/7

PC

PC com port connection to 7955 port 2RS-232 wiring with RTS/CTS handshaking

7

8

RTSSK5/13

SK5/25

Larger and more intricate MODBUS networks are possible. For example, a supervisory system may want to get flow rates from several 7955 instruments.


7955 2540 (CH07/BC) Page 7.9

7.5.2 RS-485 (half duplex) Rear Panel Connections

This Section is a reference with tables of grouped rear panel pins for each serial port.

RS-485 Serial Interface Pin Group (Serial Port ‘1’)

Note: There is no support for RS-485 on serial port one.

RS-485 Serial Interface Pin Group (Port ‘2’)

7955 (D-Type) Function

Comm 2 Rx/Tx+ SK5/11 Transmit/receive data +

Comm 2 Rx/Tx- SK5/23 Transmit/receive data -












Note: This optional serial port is available when option board 79558 is installed inside the 7955






Note: This optional serial port is available when option board 79558 is installed inside the 7955

A typical MODBUS network with ‘Prover’ 7955 and two ‘Metering’ 7955 Flow computers is shown below:

Tx/Rx-

Tx/Rx+

Signal Ground

7951

SK3/1

SK3/9

SK3/5

7955Prover

7951

SK3/1

SK3/9

SK3/5

Tx/Rx-

Tx/Rx+

Signal Ground

Stream 1 Stream 2

SK5/8

SK5/20

SK5/7


Page 7.10 7955 2540 (CH07/BC)

7.6 After Connecting up to the 7955 Serial Port … This Section explains how to proceed with configuring the communication parameters of the 7955 instrument after all the wiring to external communication devices is completed, as guided in Section 7.5. RS-232: Complete Section 7.6.1 and then complete Section 7.6.2 RS-485: Complete Section 7.6.1 and then complete Section 7.6.3

7.6.1 General RS-232C/485 Port Configuration This Section is for configuring basic communication parameters before moving on to the RS-232C and RS-485 configuration sections. Objective:

Set-up the basic communication parameters for each serial port with an RS-232 (point-to-point) or RS-485 (multiple-drop) network connection.

What to do here: Follow these instructions for each port:

1. Navigate to this menu: <“Configure”>/<”Other parameters”>/<“Communications”>/<“Ports”>

2. Select the sub-menu for a serial port.

3. Work through this menu data checklist: (Note: Some localised menu searching is required)

Menu Data Name Instructions and Comments

Port Baud rates Select a transmission rate that is compatible with other networked device(s)

Port Char Format Select a character format that is compatible with for other networked device(s)

Port handshaking Select the option descriptor of either “None”, “Xon/Xoff” or “CTS/RTS”

Port RS232 / 485 Select the serial interface standard for the network. Also, read Note B

Notes: A On-screen menu data names incorporate a number to identify the associated serial port.

B Not all 7955 communication ports have support RS-485. For further information, see page 7.1.

4. Repeat all previous steps for each RS-232/485 port that you intend to use.

(End of instructions)

7.6.2 RS-232 Configuration This Section is for completing the configuring of software parameters for a point-to-point communication link with another RS-232C device. Objective: Set-up the basic communication parameters for serial ports with an RS-232C connection. What to do here: Follow these instructions:


2. Select the sub-menu for a serial port with the RS-232C connection

3. Locate the menu data page with a descriptor of “Comms port owner” (or similar)

4. Select an option descriptor

Select the option with “Printer” when the RS-232C device is an ASCII compatible output device, such as a printer. Otherwise, select either “Master” or “Slave”, depending on which data services are needed.

5. Test the RS-232C connection, perhaps by printing a report



7955 2540 (CH07/BC) Page 7.11

7.6.3 RS-485 Configuration This Section is for completing the configuring of software parameters for serial ports with an RS-485 communication link into a multi-drop (MODBUS Master/Slave) network. Objective:

Set-up the 7955 to function as a MODBUS Slave through the port. This will allow for ‘remote’ accessing of various application data services by a MODBUS Master. What to do:

Follow these instructions:

1. Ensure that general port parameters have already been configured, as guided in Section 7.6.1


3. Select the sub-menu for a RS-485 port

4. Work through the checklist of Table 7.7


Table 7.7: RS-485 Software Parameters

Menu Data Name Instructions and Comments Notes?

Comms port owner Select the option descriptor with “MODBUS Slave” A

Port MODBUS mode Select the transmission mode (as agreed for the Master) A

MODBUS word order Selection is dependent on configuration of the Master A, C

MODB slave add ‘Set’ a value for the MODBUS base address of the port (slave) A, C, D

P MODBUS Features Select data services that are accessible by a Master (through this port) A, B

Long reg access Selection is dependent on configuration of the Master A, C

MODB precision Selection is dependent on configuration of the Master A, C

Notes: A On-screen menu data names incorporate a number to identify the associated serial RS-485 port B Table 7.8 shows how the multiple-choice option descriptors relate to enabling access to one or more data

services through a port. A summary of all data services can be found in Section 7.2.2 on page 7.3 C See page 7.4 for guidance D The 7955 Flow Computer can be MODBUS Slaves at different base addresses on each port. It is possible to

have an identical base address on two or more ports when they are not connected to the same network.

Table 7.8: Data Service Enabling Codes

Option Descriptors DBM A&E HSL ‘1’ HSL ‘2’ ARCH

None

Alarm

Alarm + List1

Alarm+List1+List2

Alarm + L1+L2+DL

= Enabled; DBM = Database, A&E = Historical Alarm & Event Logs;

HSL = High Speed List; ARCH = Data Archives


Page 7.12 7955 2540 (CH07/BC)

7.7 After Connecting up to the 7955 Ethernet Port … This Section explains how to proceed with configuring the communication software parameters of the 7955 after the Ethernet port is connected to an Ethernet network. For connection details, return to page 7.6. What to do: Decide if the 7955 instrument is to be an Ethernet Server, an Ethernet Client of another 7955

instrument, or both. (Guidance is provided below)

Once you have decided, follow the instructions for configuring the 7955 instrument Client? This is similar to the 7955 instrument being a MODBUS Master device. A 7955 Ethernet Client has to be registered with a 7955 Ethernet Server so it can use ‘Peer-to-Peer Lists’ to update the software parameter database of that Server. It can also communicate with remote ‘Stream’ Flow Computers during a meter proving session. Server? This is similar to the 7955 instrument being a MODBUS slave device. However, a 7955 Ethernet Server allows up to two registered (known) Ethernet Clients to access (1) software parameters in the database, (2) ‘High Speed Lists’, (3) ‘Historical Alarm and event logs’ and (4) the parameter archives. All Ethernet Clients must be MODBUS TCP/IP compliant devices. 7955 Client Configuration No Ethernet port configuring is required unless the 7955 instrument is also to be configured as a server. Extra pages following this Chapter will have a full guide to configuring and using the peer-to-peer function. Chapter 16 is dedicated to explaining the 7955 support for meter proving. 7955 Server Configuration Follow these instructions:

(Steps 1 to 4 set-up the server function) 1. Navigate to this menu: <“Configure”>/<”Other parameters”>/<“Communications”>/<“Ports”>

2. Select blue, lettered soft-key alongside the descriptor with “Ethernet server”

3. Work through the parameter checklist of Table 7.9 in the deliberate order shown.

Note: The IP address MUST ALWAYS be the parameter that is edited last of all in this step. Otherwise, a power cycle is required, followed by re-programming of all the Ethernet server parameters

4. Monitor the <Server port status> parameter for a short period

(Steps 5 to 11 register two clients A and B with this server)

5. Re-navigate to this menu: <“Configure”>/<”Other parameters”>/<“Communications”>/<“Ports”>

6. Select blue, lettered soft-key alongside the descriptor with “Ethernet client A” or “Ethernet client B”

7. Work through the parameter checklist of Table 7.10 in the deliberate order shown.

Note: The IP address MUST ALWAYS be the parameter that is edited last of all in this step. Otherwise, a power cycle is required, followed by re-programming of all the Ethernet Client parameters

8. Locate the menu data page with “Client A configure” (for A) or “Client B configure” (for B)

9. Change the soft-command (option descriptor) to “Configure”

Note: Use the “Un-configure” soft-command to sever the connection with a 7955 Server

10. Monitor the <Enet Client status> parameter for a short period

11. Repeat steps 5 to 10 if there is a second client to register


7955 2540 (CH07/BC) Page 7.13

The 7955 Ethernet Server function is now ready to respond to MODBUS TCP/IP requests from the registered clients (A and B). However, ‘High Speed Lists’ and ‘Peer-to-Peer Lists’ services will require additional configuring before they can be used. The extra pages after this Chapter will have a full guide to these services. Should this 7955 go through a power-cycle, the Ethernet Server re-starts but is free of clients. Connections with registered clients will need to be re-established using the <Client configure> parameter on the server.

Table 7.9: Ethernet Server Parameters

Menu Data Name Instructions and Comments Default Setting

Server port number Leave it with the default setting 502

Eprt MODB word order Select the Word Swap Mode. See page 7.4 for guidance “Modbus default”

Eport Modbus UI Unit Identifier. This is equivalent to the MODBUS base address of a slave device.

9

Eport MODB features This makes data services available through the Ethernet port.

Table 7.1 can assist with the choices available None

Eprt MODB reg access Choose if all the MODBUS messages are of the single or multiple register access type. (See page 7.4 for guidance)

“Multiple registers”

Eport MODB precision Choose whether 32-bit or 64-bit floating-point values are coded in the data component of the MODBUS messages

“Single” (32-bit)

Eport IP address * Edit an IP address for this 7955 Ethernet Server. Ensure the address is available first before editing, even if network is private.

0.0.0.0

Abbreviations: “Eport” or “Eprt” = Ethernet port, “IP” = Internet Protocol, “MODB” = MODBUS,

“UI” = Unit Identifier, “reg” = register

Table 7.10: Ethernet Client A/B Parameters

Menu Data Name Instructions and Comments Default Setting

<Client port number> This should match the value SET for the <Server port number> parameter listed in Table 7.9

502

<Clt MODB word order> Choose option that is compatible with the Ethernet Client. See page 7.4 if guidance is required

“Modbus default”

<Clt MODB reg access> Choose option that is compatible with the Ethernet Client. . (See page 7.4 for guidance)

“Multiple registers”

<Client IP address> Register the IP address of the Ethernet Client. Take care when editing this since there is no validation of the address or format

127.0.0.1

Abbreviations: “CltA” or “ClientA” = Ethernet Client A, “IP” = Internet Protocol, “MODB” = MODBUS,

“reg” = register

Table 7.11: Data Services Enabling Codes

Option Descriptors DBM A&E HSL ‘1’ HSL ‘2’ ARCH

None

Alarm

Alarm + List1

Alarm+List1+List2

Alarm + L1+L2+DL

= Enabled; DBM = Database, A&E = Historical Alarm & Event Logs;

HSL = High Speed List; ARCH = Data Archives


Page 7.14 7955 2540 (CH07/BC)

7.8 7955 Database access over a MODBUS network This Section demonstrates how a (non-7955) MODBUS Master and a (non-7955) Ethernet Client can communicate with the software parameter database of a 7955 MODBUS Slave/Ethernet Server.

7.8.1 Introduction There are several types of information that can be obtained from the software parameter database:

1. Parameter value (in base units of measurement) 2. Parameter value status 3. Data size and data type attributes for a parameter (location) value

The 7955 series uses a unique index called a location identification (ID) number. There is a unique ID number for every stored software parameter. The location ID number is not normally displayed, but pressing the ‘a’ soft-key when a database variable (menu data page) is displayed, will display the number on the fourth line. MODBUS registers are expressed as the database location ID number minus 1. Therefore, a requesting device will ask for MODBUS register 16 in order to read the data in database location 17.

Notice Parameter attributes and location identification (ID) numbers of the database with your installed software is likely to be different to those used in these examples. For a full list of locations, locate the ASCII text file with the filename extension ‘.MAN’ on your ‘FC CONFIG’ 5 installation disk.

A number of worked examples are provided for each information type. Every example features objectives, actions, and results. Adapt the examples to suit your requirements.

Objective For an example, the objective could be to read a value from a specific location.

Action(s) This consists of one or more ‘read’ and ‘write’ MODBUS protocol commands (framed messages), shown as a sequence of hexadecimal values. The framed messages need to be transmitted by the MODBUS Master or Client. Responses are also shown as a sequence of hexadecimal values.

Table 7.13 contains a list of all the abbreviations of meanings that can appear with a sequence. Use them to distinguish the important elements of the sequence.

Result This is a brief analysis of the MODBUS response to an action. There may be a reference to additional information. Some software parameters may have a “No access” security attribute and, therefore, be permanently unavailable. The response from a command to read such data is shown in Table 7.12.

Table 7.12: "No Access" to Data Response

Receive 0A 83 …

Meaning Slv. Err. …

5 This is a PC-based package for interacting with the 7955. It is available to download from the web site(s) listed on the back page.


7955 2540 (CH07/BC) Page 7.15

Table 7.13: Abbreviations for Interpreting Elements of Transmit and Receive Sequences

Abbreviations Meaning

Slv. The MODBUS slave base address

UI The MODBUS/TCP unit identifier – similar to the slave base address

Err. Error code. E.g. 83 = Error reading / Exception

Fn. MODBUS Function code. E.g. 03 = Read multiple registers

Transact ID Transaction Identifier – this is usually 0 (0x0000)

Protocol ID Protocol Identifier – this is usually 0 (0x0000)

Length Number of bytes that follow (excluding Ethernet packet)

Reg. Cnt Number of registers to read or write / Number of registers read or written

Reg. ID MODBUS Register number

DC Data Count – The number of bytes of data that follow

The Data Data bytes that contain the useful information

Chk sum Calculated checksum - always two bytes at the end

EOT End of text marker


Page 7.16 7955 2540 (CH07/BC)

7.8.2 7955 Database Information: Software Parameter Values MODBUS (Master/Slave):

Software parameter values are mapped within the first 10,000 registers of the MODBUS register map directly associated with the programmed base address of a 7955 MODBUS slave. Our examples assume the 7955 MODBUS Slave (port) is configured with a base address of “01”. MODBUS/TCP (Client/Server):

Software parameter values are mapped within the first 10,000 registers of the MODBUS register map directly associated with the unit identifier (UI) – base address – of a 7955 Ethernet Server. Our examples assume that the server has been configured with a base address (UI) of “09”. Notes: Identification (ID) numbers of the software parameters with your installed software may be

different to those used in these examples. All request and response messages shown here use (1) the ‘default word order’ mode, (2) 32-bit single

precision encoding and (3) multiple read/write register MODBUS functions. Example 1: Read base density value from database location 0787

MODBUS Action: Read from MODBUS register 0786

Transmit 01 03 03 12 00 02 64 4A

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk. Sum

Receive 01 03 04 44 54 A0 00 D7 13

Meaning Slv. Fn. DC The Data Chk. Sum MODBUS/TCP Action: Read from MODBUS register 0786

Transmit 00 00 00 00 00 06 09 03 03 12 00 02

Meaning Transact ID Protocol ID Length UI Fn. Reg. ID Reg. Cnt.

Receive 00 00 00 00 00 07 09 03 04 44 54 A0 00 Meaning Transact ID Protocol ID Length UI Fn. DC The Data

Result: The data value part of the reply, 0x4454A000, translates from a 32-bit IEEE number into the floating-point number 850.50 (in Kg/m3 – base units).

Example 2: Write base density value of 850 Kg/m3 (base units) to location 0787

MODBUS Action: Write to MODBUS register number 0786

Transmit 01 10 03 12 00 02 04 44 54 80 00 53 6A

Meaning Slv. Fn. Reg. ID Reg. Cnt DC IEEE 32-bit data value Chk. Sum

Receive 01 10 03 12 00 02 E1 89

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk. Sum MODBUS/TCP Action: Write to MODBUS register number 0786

Transmit 00 00 00 00 00 0B 09 10 03 12 00 02 04

Meaning Transact ID Protocol ID Length UI Fn. Reg. ID Reg. Cnt. DC

Transmit 44 54 80 00

Meaning The Data

Receive 00 00 00 00 00 06 09 10 03 12 00 02

Meaning Transact ID Protocol ID Length UI Fn Reg. ID Reg. Cnt.


7955 2540 (CH07/BC) Page 7.17

Example 2 Result: Base density value changes. The 0x44548000, translates from a 32-bit IEEE number into the floating- point number 850.00 (in Kg/m3 – base units).

Example 3: Read the user alarm summary from read-only location 1579

MODBUS Action:

Read from MODBUS register 1578

Transmit 01 03 01 33 06 2A 53 6A


Receive 01 03 16 20 … 20 30 30 30 30 30 30 30 00

Meaning Slv. Fn. DC The Data… A= B= C= D= X= Y= Z= -

Receive 00 DB 96

Meaning - Chk. Sum

MODBUS/TCP Action:

Read from MODBUS register 1578

Transmit 00 00 00 00 00 06 09 03 01 33 06 2A


Transmit 00 00 00 00 00 17 09 16 20 … 20 30 30

Meaning Transact ID Protocol ID Length UI DC The Data… A= B=

Receive 30 30 30 30 30 00 00

Meaning C= D= X= Y= Z= EOT EOT Result: There are 22 (0x16) bytes of returned data. Table 7.14 shows how to interpret the “ABCDXYZ” bytes

are interpreted. The rest of the returned data is padded out with 12 ASCII spaces (0x20).

Note: The returned data is a character string and is therefore unaffected by the ‘word order’ mode

Table 7.14: Interpretation of returned data

Alarm Digit Data Alarm State (ASCII Char) Comment

A 0x30 ‘0’ 0 = User Alarm ‘A’ inactive

B 0x30 ‘0’ 0 = User Alarm ‘B’ inactive

C 0x30 ‘0’ 0 = User Alarm ‘C’ inactive

D 0x30 ‘0’ 0 = User Alarm ‘D’ inactive

X 0x30 ‘0’ 0 = User Alarm ‘X’ inactive

Y 0x30 ‘0’ 0 = User Alarm ‘Y’ inactive

Z 0x30 ‘0’ 0 = User Alarm ‘Z’ inactive


Page 7.18 7955 2540 (CH07/BC)

Example 4: Check on selected option descriptor of a multiple-choice list

Objective: Check referral method selection for calculating Metering density.

MODBUS Action: Read from MODBUS register 03661 (0x0E4D)

Transmit 01 03 0E 4D 00 01 16 F5


Receive 01 03 02 00 00 B8 44

Meaning Slv. Fn. DC The Data Chk. Sum

MODBUS/TCP Action: Read from MODBUS register 03661 (0x0E4D)

Transmit 00 00 00 00 00 06 09 03 0E 4D 00 01


Receive 00 00 00 00 00 05 09 03 02 00 00

Meaning Transact ID Protocol ID Length UI Fn. DC The Data Result: The returned data value 0x0000 can be interpreted by looking at the following table:

Value Meaning

0x0000 4x5 Matrix Referral selected

0x0001 API Referral selected

Example 5: Select an option descriptor from a multiple-choice list

Objective: Select the API referral method for calculating Metering density. MODBUS Action: Write value of 0x0001 to MODBUS register 03661 (0x0E4D)

Transmit 01 10 0E 4D 00 01 02 00 01 16 F5

Meaning Slv. Fn. Reg. ID Reg. Cnt. DC The Data Chk. Sum

Receive 01 10 0E 4D 00 01 93 36

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk. Sum MODBUS/TCP Action: Write value of 0x0001 to MODBUS register 03661 (0x0E4D)

Transmit 00 00 00 00 00 07 09 10 0E 4D 00 01 02

Meaning Transact ID Protocol ID Length UI Fn. Reg. ID Reg. Cnt DC

Transmit 00 01

Meaning The Data

Receive 00 00 00 00 00 06 09 10 0E 4D 00 01

Meaning Transact ID Protocol ID Length UI Fn. Reg. ID Reg. Cnt Result: The reply indicates that the request was successful


7955 2540 (CH07/BC) Page 7.19

7.8.3 7955 Database Information: Software Parameter Status MODBUS (Master/Slave):

Software parameter states are mapped within registers 30001 to 40000 of the MODBUS register map directly associated with the programmed base address of a 7955 MODBUS slave. Our examples assume the 7955 MODBUS Slave (port) is configured with a base address of “01”. MODBUS/TCP (Client/Server):

Software parameter states are mapped within registers 30001 to 40000 of the MODBUS register map directly associated with the unit identifier (UI) – base address – of a 7955 Ethernet Server. Our examples assume that the server has been configured with a base address (UI) of “09”. Notes: Identification (ID) numbers of the software parameters with your installed software may be


precision encoding and (3) multiple read/write register MODBUS functions. Example 1: Read the status of location 0787

MODBUS Action: Read MODBUS register 30786 (30000 offset + 0787 - 1)

Transmit 01 03 78 42 00 01 3C BE


Receive 01 03 02 00 01 79 84

Meaning Slv. Fn. DC The Data Chk. sum

MODBUS/TCP Action: Read MODBUS register 30786 (30000 offset + 0787 - 1):

Transmit 00 00 00 00 00 06 09 03 78 42 00 01

Meaning Transact ID Protocol ID Length UI Fn. Reg. ID Reg. Cnt

Receive 00 00 00 00 00 05 09 03 02 00 01

Meaning Transact ID Protocol ID Length UI Fn. DC The Data

Result: The “00 01” indicates a ‘SET’ status. Refer to Table 7.16 (on page 7.20) for other states. Example 2: Change the status of location 0787

MODBUS Action: Change status to ‘LIVE’ by writing to 0x0000 to register 30786 (30000 + 0787 - 1)

Transmit 01 10 78 42 00 01 02 00 00 51 75

Meaning Slv. Fn. Reg. ID Reg. Cnt. DC The Data Chk. sum

Receive 01 10 78 42 00 01 B9 7D


MODBUS/TCP Action: Change status to ‘LIVE’ by writing to 0x0000 to register 30786 (30000 + 786)

Transmit 00 00 00 00 00 09 09 10 78 42 00 01 02

Meaning Transact ID Protocol ID Length UI Fn. Reg. ID Reg. Cnt. DC

Transmit 00 00

Meaning The Data

Receive 00 00 00 00 00 06 09 10 78 42 00 01


Result: Status has changed to “Live”. (See Table 7.15 on page 7.20 for other states)


Page 7.20 7955 2540 (CH07/BC)

Example 3: Read status of user alarm state (location ID: 1579)


Transmit 01 03 7B 5A 00 01 BC FD


Receive 01 03 02 00 FF F8 04


MODBUS/TCP Action: Read MODBUS register 31578 (30000 offset + 1579 - 1)

Transmit 00 00 00 00 00 06 09 03 7B 5A 00 01

Meaning Transact ID Protocol ID Length UI Fn. Reg. Cnt. Chk. Sum

Receive 00 00 00 00 00 05 09 03 02 00 FF

Meaning Transact ID Protocol ID Length UI Fn. DC The Data

Result: The returned data value, 0x00FF, indicates that there is no status attribute for that location. See Table 7.16 for other states

Table 7.15: Status Codes (Selection)

Value Selection

0x0000 Live state

0x0001 Set state

Table 7.16: Status Codes (Returned)

Value State Return

0x0000 Live

0x0001 Set

0x0002 Fail

0x0003 Fallback

0x00FF No state


7955 2540 (CH07/BC) Page 7.21

7.8.4 7955 Database Information: Size and Type of Software Parameter Value MODBUS (Master/Slave):

The data size and type of every software parameter value is mapped within registers 20,001 to 29,999 of the MODBUS register map directly associated with the programmed base address of a 7955 MODBUS slave. Our examples assume the 7955 MODBUS Slave (port) is configured with a base address of “01”. MODBUS/TCP (Client/Server):

The data size and type of every software parameter value is mapped within registers 20,001 to 29,999 of the MODBUS register map directly associated with the unit identifier (UI) – base address – of a 7955 Ethernet Server. Our examples assume the server is configured with a base address (UI) of “09”. Notes: Identification (ID) numbers of the software parameters with your installed software may be


precision encoding and (3) multiple read/write register MODBUS functions.

Example 1: Read size and type of data available from location 0787


Transmit 01 03 51 32 00 01 35 39


Receive 01 03 02 07 04 BB B7


MODBUS/TCP Action: Read MODBUS register 20786 (20000 offset + 0787 - 1)

Transmit 00 00 00 00 00 06 09 03 51 32 00 01


Receive 00 00 00 00 00 05 09 03 02 07 04

Meaning Transact ID Protocol ID Length UI Fn. DC The Data Result: 2 bytes of data are returned in the reply: 0x07 and 0x04

* 0x07 = Data Type Code 7 – a 32-bit floating-point number * 0x04 = 4 bytes needed to represent the floating-point value Special Note: For other data type and size codes, refer to Table 7.17 on page 7.22

Example 2: Read size and type of data available from location 1579

MODBUS Action: Read MODBUS register 21,578 (20000 offset + 1579 - 1)

Transmit 01 03 54 4A 00 01 B5 EC


Receive 01 03 02 09 16 3F DA



Page 7.22 7955 2540 (CH07/BC)

MODBUS/TCP Action: Read MODBUS register 21,578 (20000 offset + 1579 - 1)

Transmit 00 00 00 00 00 06 09 03 54 4A 00 01


Receive 00 00 00 00 00 05 09 03 02 09 16

Meaning Transact ID Protocol ID Length UI Fn. DC The Data Result: 2 bytes of data are returned in the reply: 0x09 and 0x16

* 0x09 = Data Type Code 9 – Character String * 0x16 = 22 bytes – length of character string in bytes

Table 7.17: Interpreting Responses from Type 3 Requests

Type of Data Size (Bytes) Type (Code)

Character 2 1

Unsigned 8-bit integer 2 2


Signed 16-bit integer 2 4


Signed 32-bit integer 4 6

32-bit floating point number 4 7

64-bit floating point number 8 8

Character String 22 9

Multiple-choice (List) Option 2 10

Location pointer 2 11

Time and date 16 12

Table 7.18: Unit of Measurement Category Codes

Category Code Unit Category Category

Code Unit Category

0 (No units) 20 (Not Used) 1 Temperature 21 (Not Used) 2 Pressure 22 (Not Used) 3 Differential Pressure 23 Time 4 Volume 24 Length 5 Standard Volume 25 Speed 6 Mass 26 Fraction 7 Energy 27 Saybolt Universal 8 Density 28 Saybolt Temperature 9 Standard Density 29 Absolute Zero 10 Frequency 30 Temperature Offset 11 Period 31 General 12 Dynamic Viscosity 32 (Not Used) 13 Base Dynamic Viscosity 33 (Not Used) 14 Kinematic Viscosity 34 (Not Used) 15 Base Kinematic Viscosity 35 Expansion Coefficient 16 Flow Factor 36 Youngs Modulus 17 Volume Rate 37 Velocity 18 Standard Volume Rate

19 Mass Rate


7955 2540 (CH07/BC) Page 7.23

7.8.5 7955 Database Information: Full Attributes of a Software Parameter MODBUS (Master/Slave):

The data size and type of every software parameter value is mapped within registers 40,001 to 49,999 of the MODBUS register map directly associated with the programmed base address of a 7955 MODBUS slave. Our examples assume the 7955 MODBUS Slave (port) is configured with a base address of “01”. MODBUS/TCP (Client/Server):

The data size and type of every software parameter value is mapped within registers 40,001 to 49,999 of the MODBUS register map directly associated with the unit identifier (UI) – base address – of a 7955 Ethernet Server. Our examples assume the server is configured with a base address (UI) of “09”. Notes: Identification (ID) numbers of the software parameters with your installed software may be


precision encoding and (3) multiple read/write register MODBUS functions.

Example 1: Read the full attributes of location 0787


Transmit 01 03 9F 52 00 02 4B CE


Receive 01 03 04 04 07 01 08 BA D0

Meaning Slv. Fn. DC The Data Chk. Sum MODBUS/TCP Action: Read MODBUS register 40786 (40000 offset + 0787 - 1)

Transmit 00 00 00 00 00 06 09 03 9F 52 00 02


Receive 00 00 00 00 00 05 09 03 02 04 07 01 08 Meaning Transact ID Protocol ID Length UI Fn. DC The Data

Result: 4 bytes of data are returned in the reply:

* 0x04 = 4 bytes – required to store a 32-bit floating-point number * 0x07 = Data Type Code 7 – software parameter value is a 32-bit floating-point number * 0x01 = Status Code 1 – “Live” value state * 0x08 = Unit of Measurement Category Code 9 – Density units Special Note: For interpreting other codes, refer to Table 7.17 (on page 7.22) and Table 7.18 (on page 7.22) The reply data is unaffected by the ‘word order’ mode


Page 7.24 7955 2540 (CH07/BC)

7.9 Historical Alarm Log access over a MODBUS Network This Section demonstrates how a MODBUS Master/Ethernet Client can access “LIVE” information from the Historical Alarm Log of a 7955 MODBUS Slave/Ethernet Server.

Refer to Chapter 8 if an explanation for the Historical Alarm Log is required.

7.9.1 Introduction Information from the Historical Alarm Log is available to a MODBUS Master through the register map of Virtual Address ‘1’ (base address + offset of 1).

Warning! It is not advisable to clear or accept alarms using the front panel while the Historical Alarm Log is being queried by a MODBUS master. Doing so could result in the MODBUS Master having an incorrect view of the content.

Worked examples are provided to demonstrate the correct method for (1) obtaining details of an alarm, (2) accepting that alarm, and (3) clearing that alarm Every example features objectives, request/response sequences, and an explained result. Adapt the examples to suit your requirements.




Result This is a brief analysis of the MODBUS Slave response to an action. There may be a reference to additional information.

















7955 2540 (CH07/BC) Page 7.25

7.9.2 Worked Examples Unless otherwise stated, all request and response messages shown here use (1) the ‘default word order’ mode, (2) 32-bit single precision encoding and (3) multiple read/write register MODBUS functions.

A base address of “01” (for MODBUS) and “09” (for MODBUS/TCP) has been assumed for or examples. Example 1 (of 3) Objectives: 1. Find out how many alarms are in the Historical Alarm Log

2. Retrieve identification numbers for logged alarms

3. Make information on a specific alarm available

4. Get further information about the alarm that was selected in step three

5. Accept the alarm that was selected in step three

6. Clear the alarm that was selected in step three.

Step 1 is to find out how many alarms are in the Historical Alarm Log.

MODBUS Action 1 of 1: Count alarms by reading MODBUS register 1,999

Transmit 02 03 07 CF 00 01 B5 72


Receive 02 03 02 00 10 FD 88

Meaning Slv. Fn. D.C. The Data Chk. Sum

MODBUS/TCP Action 1 of 1: Count alarms by reading MODBUS register 1,999

Transmit 00 00 00 00 00 06 0A 03 07 CF 00 01

Meaning Transact ID Protocol ID Length UI+1 Fn. Reg. ID Reg. Cnt.

Receive 00 00 00 00 00 0? 0A 03 02 00 10

Meaning Transact ID Protocol ID Length UI+1 Fn. DC The Data

Result: Reply data indicates that there are 16 (0x0010) alarms in the Historical Alarm Log.

Step 2 is to retrieve the identification number of the second oldest alarm

MODBUS Action 1 of 1: Read MODBUS register 1

Transmit 02 03 00 01 00 01 D5 F9


Receive 02 03 02 00 17 BC 4A


MODBUS/TCP Action 1 of 1: Read MODBUS register 1

Transmit 00 00 00 00 00 06 0A 03 00 01 00 01


Receive 00 00 00 00 00 05 0A 03 02 00 17

Meaning Transact ID Protocol ID Length UI+1 Fn. DC The Data Result: Reply data indicates that the unique alarm ID is 0x0017


Page 7.26 7955 2540 (CH07/BC)

Note: Identification numbers of presently logged alarms are held in MODBUS registers 0 to 29 of the map for virtual address ‘1’. The first entry in the Alarm Historical Log is always at MODBUS register 1. For the purpose of this worked example, one alarm identification number is sufficient.

Step 3 is to make information on an alarm available. This is mandatory for remaining steps.

MODBUS Action 1 of 2: Make information available on the second alarm

Write alarm ID number, 0x0017, to MODBUS register 999

Transmit 02 10 03 E7 00 01 02 00 17 D6 79


Receive 02 10 03 E7 00 01 B1 89

Meaning Slv. Fn. Reg.ID Reg. Cnt. Chk. Sum

MODBUS/TCP Action 1 of 2: Make information available on the second alarm

Write alarm ID number, 0x0017, to MODBUS register 999

Transmit 00 00 00 00 00 09 0A 10 03 E7 00 01 02

Meaning Transact ID Protocol ID Length UI+1 Fn. Reg. ID Reg. Cnt. DC

Receive 00 17

Meaning The Data

Receive 00 00 00 00 00 06 0A 10 03 E7 00 01

Meaning Transact ID Protocol ID Length UI+1 Fn. Reg.ID Reg. Cnt. Result: Reply data indicates that the selection has been made

MODBUS Action 2 of 2:

Check that information is now available by reading MODBUS register 999

Transmit 02 03 03 E7 00 01 34 4A


Receive 02 03 02 00 17 BC 4A


MODBUS/TCP Action 2 of 2:

Check that information is now available by reading MODBUS register 999

Transmit 00 00 00 00 00 06 0A 03 03 E7 00 01


Receive 00 00 00 00 00 05 0A 03 02 00 17

Meaning Transact ID Protocol ID Length UI+1 Fn. DC The Data Result: Reply data indicates that the current alarm ID is confirmed to be 0x0017. Note: A reply of 0x0000 indicates that no alarm has been selected


7955 2540 (CH07/BC) Page 7.27

Step 4 is to get further information about the alarm that was selected in step three. To get information about another alarm, repeat step three but use another identification number.

MODBUS Action 1 of 1: Obtain alarm text length by reading MODBUS register 2000

Transmit 02 03 07 D0 00 01 84 B4


Receive 03 03 02 00 12 84 B4

Meaning Slv. Fn. DC The Data Chk. Sum MODBUS/TCP Action 1 of 1: Obtain alarm text length by reading MODBUS register 2000

Transmit 00 00 00 00 00 06 0A 03 07 D0 00 01


Receive 00 00 00 00 00 05 0A 03 02 00 12

Meaning Transact ID Protocol ID Length UI+1 Fn. DC The Data Result: Reply data indicates that the alarm text length is 18 bytes (0x0012). At present, the length returned

is always 18 bytes. Divide the length by 2 to work out the number of register to request when asking for the text. Do not assume the length will always be 18 bytes.

MODBUS Action 1 of 1: Obtain ASCII alarm text by reading MODBUS register 1011

Transmit 02 03 03 F3 00 09 75 88


Receive 02 03 12 53 69 6D 65 70 65 72 69 6F 64 20

Meaning Slv. Fn. DC ‘T’ ‘i’ ‘m’ ‘e’ ‘p’ ‘e’ ‘r’ ‘i’ ‘o’ ‘d’

Receive 6E 6F 20 63 61 6C 00 7C EB

Meaning ‘n’ ‘o’ ‘c’ ‘a’ ‘l’ EOT Chk. Sum MODBUS/TCP Action 1 of 1: Obtain ASCII alarm text by reading MODBUS register 1011

Transmit 00 00 00 00 00 06 0A 03 03 F3 00 09


Receive 00 00 00 00 00 15 0A 03 12 53 69 6D 65 70

Meaning Transact ID Protocol ID Length UI+1 Fn. DC ‘T’ ‘I’ ‘m’ ‘e’ ‘p’

Receive 65 72 69 6F 64 20 63 61 6C 00

Meaning ‘e’ ‘r’ ‘I’ ‘o’ ‘d’ ‘c’ ‘a’ ‘l’ EOT Result: Reply data contains the base alarm message of “Timeperiod no cal”. See next action to find out the

additional character following the base message. MODBUS Action 1 of 1: Obtain alarm text code and qualifier by reading MODBUS register 1010:

Transmit 02 03 03 F2 00 02 65 8F

Meaning Slv. Fn. Reg ID Reg Cnt. Chk sum

Receive 02 03 04 00 0B 31 20 65 8F

Meaning Slv. Fn. D.C. The data Chk sum


Page 7.28 7955 2540 (CH07/BC)

MODBUS/TCP Action 1 of 1: Obtain alarm text code and qualifier by reading MODBUS register 1010:

Transmit 00 00 00 00 00 06 0A 03 03 F2 00 02


Receive 00 00 00 00 00 07 0A 03 04 00 0B 31 20 Meaning Transact ID Protocol ID Length UI+1 Fn. DC The Data

Result: 0x000B = A code for the alarm text – not to be confused with the alarm entry ID (from earlier) 0x31 = Represents ASCII character “1” – for metering-point/stream/channel one 0x20 = Alarm Type ‘2’ (2 = Present) + Alarm State ‘0’ (0 = Alarm Not Accepted) Other possible results…

Type of alarm: “0”=Off, “1”=On, “2”=Present State of alarm: “0”=Not Accepted, “1”=Accepted

MODBUS Action 1 of 1: Retrieve time and date of selected alarm by reading MODBUS register 1009

Transmit 02 03 03 F1 00 08 15 88


Receive 02 03 10 00 21 00 06 00 0D 00 0A 07 CE 00 1C Meaning Slv. Fn. DC The Data

Receive 00 04 01 2D 32 6B

Meaning The Data Chk. Sum MODBUS/TCP Action 1 of 1: Retrieve time and date of selected alarm by reading MODBUS register 1009

Transmit 00 00 00 00 00 06 0A 03 03 F1 00 08


Receive 00 00 00 00 00 12 0A 03 10 00 21 00 06 00 0D Meaning Transact ID Protocol ID Length UI Fn. DC 33 seconds 6 minutes 13 hours

Receive 00 0A 07 CE 00 1C 00 04 01 2D

Meaning 10th. Month 1998 28th. (Oct) Wednesday Day of year Result: When viewing the Historical Alarm Log entry you would see “28-10-98 13:06:33” on the third line Special Notes: The order of date/time character strings in packets are unaffected by the ‘word order’ mode.

Step 5 is to accept the alarm that was selected in step three. MODBUS Action 1 of 1: Write 0x0000 to MODBUS register 1004

Transmit 02 10 03 EC 00 01 02 00 00 97 0C


Receive 02 10 03 EC 00 01 C0 4B



7955 2540 (CH07/BC) Page 7.29

MODBUS/TCP Action 1 of 1: Write 0x0000 to MODBUS register 1004

Transmit 00 00 00 00 00 09 0A 10 03 EC 00 01 02


Receive 00 00

Meaning The Data

Transmit 00 00 00 00 00 06 0A 10 03 EC 00 01

Meaning Transact ID Protocol ID Length UI+1 Fn. Reg. ID Reg. Cnt. Result: The alarm entry selected through register 999 has been accepted. Information, such as the base

alarm message, remains available until another alarm entry is selected.

Step 6 is to clear the alarm that was selected in step three.

MODBUS Action 1 of 1: Write 0x01 to MODBUS register 1004 (0x3EC)

Transmit 0B 10 03 EC 00 01 02 00 01 56 CC


Receive 0B 10 03 E7 00 01 C0 4B


MODBUS/TCP Action 1 of 1: Write 0x01 to MODBUS register 1004 (0x3EC)

Transmit 00 00 00 00 00 08 0A 10 03 EC 00 01 02


Transmit 00 01

Meaning The Data

Receive 00 00 00 00 00 05 0A 10 03 E7 00 01

Meaning Transact ID Protocol ID Length UI+1 Fn. Reg. ID Reg. Cnt. Result: The alarm (selected through register 999) has been cleared. However, the conditions that caused the

alarm may still be present and the same alarm would then be raised with a new identification number. Information such as the alarm text is now unavailable.

Example 2 (of 3) Objective: Clear all alarms from the Historical Alarm Log

MODBUS Action: Write 0x01 to MODBUS register 2001

Transmit 02 10 07 D1 00 01 02 00 01 17 E1


Receive 02 10 07 D1 00 01 50 B7



Page 7.30 7955 2540 (CH07/BC)

MODBUS/TCP Action: Write 0x01 to MODBUS register 2001

Transmit 00 00 00 00 00 09 0A 10 07 D1 00 01 02


Transmit 00 01

Meaning The Data

Receive 00 00 00 00 00 06 0A 10 07 D1 00 01


Result: All alarms cleared. However, the conditions that caused the logged alarms may still be present and so

the same alarms would be raised again, but with new identification numbers.

Example 3 (of 3) Objective: Retrieve abbreviated summary of the Historical Alarm Log

MODBUS Action: Read MODBUS register 2010

Transmit 02 03 07 D9 00 03 D5 77


Receive 01 03 06 00 00 00 0E 10 00 59 86


MODBUS/TCP Action: Read MODBUS register 2010

Transmit 00 00 00 00 00 05 03 07 D9 00 03

Meaning Transact ID Protocol ID Length Fn. Reg. ID Reg. Cnt.

Receive 00 00 00 00 00 08 0A 03 06 00 00 00 0E 10 Meaning Transact ID Protocol ID Length UI+1 Fn. DC The Data

Receive 00 Meaning

Result: The reply data is interpreted as follows:

0x00 (Byte 1) = Number of system class alarms that have not been accepted = 0 0x00 (Byte 2) = Number of input class alarms that have not been accepted = 0 0x00 (Byte 3) = Number of limit class alarms that have not been accepted = 0 0x0E (Byte 3) = Total number of system class alarms (accepted or otherwise) = 14 0x10 (Byte 5) = Total number of input class alarms (accepted or otherwise) = 16 0x00 (Byte 6) = Total number of limit class alarms (accepted or otherwise) = 0

Note: The reply data is a character string and is therefore unaffected by the ‘word order’ mode.


7955 2540 (CH07/BC) Page 7.31

7.10 Historical Event Log access over a MODBUS network This Section demonstrates how a MODBUS Master/Ethernet Client can access “LIVE” information from the Historical Event Log of a 7955 MODBUS Slave/Ethernet Server. Refer to Chapter 8 if an explanation for the Historical Event Log is required.

7.10.1 Introduction Information from the Historical Event Log is retrievable through the map of MODBUS registers associated with ‘Virtual Address 1’ (base address + offset of 1).

Warning!

It is not advisable to clear or accept events using the front panel while the Historical Event Log is being queried by a MODBUS master. This could otherwise result in the MODBUS master having an in-correct view of the content.

Worked examples are provided to demonstrate the correct method for (1) obtaining details of an event, (2) accepting that event and (3) clearing that event

Every example features objectives, actions, and a result analysis.





















Page 7.32 7955 2540 (CH07/BC)


A base address of “01” (for MODBUS) and “09” (for MODBUS/TCP) has been assumed for our examples.

Objectives: 1. Find out how many alarms are in the Historical Event Log

2. Retrieve identification numbers for recorded (logged) events

3. Make information available on a specific event

4. Get further information about the event that was selected in step three

5. Accept/Clear the event that was selected in step three. Step 1 is to find out how many events are in the Historical Event Log.

MODBUS Action 1 of 1: Read MODBUS register 11,999

Transmit 02 03 2E DF 00 01 BC EB


Receive 02 03 02 00 96 7C 2A


MODBUS/TCP Action 1 of 1: Read MODBUS register 11,999

Transmit 00 00 00 00 00 06 0A 03 2E DF 00 01

Meaning Transact ID Protocol ID Length UI+1 Fn. Reg. ID Reg. Cnt

Receive 00 00 00 00 00 05 0A 03 02 00 96


Result: Returned data indicates that there are 150 (0x0096) events in the Historical Event Log. Step 2 is to retrieve identification numbers for recorded (logged) events.

MODBUS Action 1 of 1: Retrieve ID number of the oldest event by reading register 10,000

Transmit 02 03 27 10 00 01 8F 48


Receive 02 03 02 02 D5 3C BB


MODBUS/TCP Action 1 of 1: Retrieve ID number of the oldest event by reading register 10000

Transmit 00 00 00 00 00 06 0A 03 27 10 00 01

Meaning Transact ID Protocol ID Length UI+1 Fn. Reg. ID. Reg. Cnt.

Receive 00 00 00 00 00 05 0A 03 02 02 D5


Result: Reply indicates that the unique event ID is 0x02D5.

Notes: Identification (ID) numbers of recorded events are available from MODBUS registers 10,000 to

10,149. The ID of the oldest recorded entry in the Historical Event Log is at register 10,000. For the purpose of our worked example, one event identification number is sufficient. In practice, all identification numbers would need to be retrieved and stored for repeating steps.


7955 2540 (CH07/BC) Page 7.33

Step 3 is to make information available about a specific event. This is mandatory for remaining steps.

MODBUS Action 1 of 2: Make information available for the first event

Write the event identification number (i.e. 0x02D5) to MODBUS register 10,999

Transmit 02 10 2A F7 00 01 02 02 D5 EC DA


Receive 02 10 2A F7 00 01 B8 10

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk. Sum MODBUS/TCP Action 1 of 2: Make information available for first event

Write the event identification number (i.e. 0x02D5) to MODBUS register 10,999

Transmit 00 00 00 00 00 09 0A 10 2A F7 00 01 02


Transmit 02 D5

Meaning The Data

Receive 00 00 00 00 00 06 0A 10 2A F7 00 01


Result: Reply indicates that the selection has been made.

MODBUS Action 2 of 2: Check that information for selected event is now available by read register 10,999

Transmit 02 03 2A F7 00 01 3D D3


Receive 02 03 02 02 D5 3C BB

Meaning Slv. Fn. DC The Data Chk. Sum MODBUS Action 2 of 2: Check that information for selected event is now available by read register 10,999

Transmit 00 00 00 00 00 06 0A 03 2A F7 00 01


Receive 00 00 00 00 00 05 0A 03 02 02 D5

Meaning Transact ID Protocol ID Length UI+1 Fn. DC The Data Result: Reply indicates that the current event ID is confirmed to be 0x02D5.

Step 4 is to get further information about the event that was selected in step 3. To get information about another event, repeat step 3 but use another event identification number.

MODBUS Action 1 of 1: Retrieve event text length by reading MODBUS register 12,000

Transmit 02 03 2E E0 00 01 8C E7


Receive 03 03 02 00 14 FC 4B



Page 7.34 7955 2540 (CH07/BC)

MODBUS/TCP Action 1 of 1: Retrieve event text length by reading MODBUS register 11,012

Transmit 00 00 00 00 00 06 0A 03 2E E0 00 01


Receive 00 00 00 00 00 05 0A 03 02 00 14

Meaning Transact ID Protocol ID Length UI+1 Fn. DC The Data Result: Reply data indicates that the event text length is 20 bytes (0x0014). At present, the length returned is always 20 bytes. Divide the length by 2 to work out the number of register to request when asking for the event text. Do not assume the event text length will always be 18 bytes.

MODBUS Action 1 of 1: Retrieve event text by reading MODBUS register 11,012

Transmit 02 03 2B 04 00 0A 8D DB

Meaning Slv. Fn. Reg. ID Reg. Cnt Chk. Sum

Receive 02 03 14 6D 41 20 4F 2F 50 20 38 20 63

Meaning Slv. Fn. DC The Data... (mA O/P 8 cycle time)

Receive 79 63 6C 65 20 74 69 6D 65 00 3A AD

Meaning The Data… Chk. Sum

MODBUS/TCP Action 1 of 1: Retrieve event text by reading MODBUS register 11,012

Transmit 00 00 00 00 00 06 0A 03 2B 04 00 0A


Receive 00 00 00 00 00 17 0A 03 14 6D 41 20 4F Meaning Transact ID Protocol ID Length UI+1 Fn. DC ‘m’ ‘A’ ‘O’

Receive 2F 50 20 38 20 63 79 63 6C 65 20 74 69 Meaning ‘/’ ‘P’ ‘8’ ‘c’ ‘y’ ‘c’ ‘l’ ‘e’ ‘t’ ‘i’

Receive 6D 65 00

Meaning ‘m’ ‘e’ EOT

Result: Reply data contains the ASCII encoded event text. It is unaffected by the ‘word order’ mode. MODBUS Action 1 of 1: Retrieve location ID, event type, and event state by reading register 11,010

Transmit 02 03 2B 02 00 02 6C 1C


Receive 02 03 04 00 72 01 01 A9 78


MODBUS/TCP Action 1 of 1: Retrieve location ID, event type, and event state by reading register 11,010

Transmit 00 00 00 00 00 06 0A 03 2B 02 00 02


Receive 00 00 00 00 00 07 0A 03 04 00 72 01 01 Meaning Transact ID Protocol ID Length UI+1 Fn. DC The Data


7955 2540 (CH07/BC) Page 7.35

Result: 0x0072 = Location ID 0114 1st. 0x01 = Type (0x00=Auto, 0x01=User, 0x02=Period) 2nd. 0x01 = State (0x00=Pending, 0x01=Accepted)

MODBUS Action 1 of 1: Obtain date/time stamp for the same event by reading MODBUS register 11,009

Transmit 02 03 2B 01 00 08 1C 1B


Receive 02 03 10 00 04 00 33 00 09 00 06 07 D0 Meaning Slv. Fn. DC = 4 seconds = 51 mins. = 9 hours = June = 2000

Receive 00 08 00 05 00 A0 84 82

Meaning = 8th. (June) = Thursday = 160th. Day Chk. Sum

MODBUS/TCP Action 1 of 1: Obtain date/time stamp for the same event by reading register 11,009

Transmit 00 00 00 00 00 06 0A 03 2B 01 00 08


Receive 00 00 00 00 00 13 0A 03 10 00 04 00 33 Meaning Transact ID Protocol ID Length UI+1 Fn. DC = 4 seconds = 51 mins.

Receive 00 09 00 06 07 D0 00 08 00 05 00 A0

Meaning = 9 hours = June = 2000 = 8th. (June) = Thursday = 160th. Day

Result: When viewing the Historical Event Log entry you would see “08-06-00 09:51:04” on the third line Special Notes: The order of this data packet is unaffected by the ‘word order’ mode.

MODBUS Action 1 of 1: Retrieve event data for the same event by reading MODBUS register 11,011

Transmit 02 03 2B 03 00 19 7D D7


Receive 02 03 32 45 3B 80 00 … 80 53


MODBUS/TCP Action 1 of 1: Retrieve event data for the same event by reading MODBUS register 11,011

Transmit 00 00 00 00 00 06 0A 03 2B 03 00 19


Receive 00 00 00 00 00 35 0A 03 32 45 3B 80 00 Meaning Transact ID Protocol ID Length UI+1 Fn. DC The Data

Result: 453B8000 is an 32-bit IEEE number representing 3000.00 (Old = 3000.0) - ignore the other 46 bytes Special Notes: The order of this data packet is unaffected by the ‘word order’ mode. You must use MODBUS function 3 irrespective of whether port is configured for single register access When the data part of the reply represents an option selection code, the code is in the first byte. You can

retrieve option text by reading 22 bytes from registers 11,013 (old option ) and 11014 (new option)


Page 7.36 7955 2540 (CH07/BC)

Step 5 is to clear the selected event from Historical Event Log once all associated data has been retrieved

MODBUS Action 1 of 1: Write value of the clearance code (0x0001) to MODBUS register 11,004

Transmit 02 10 2A FC 00 01 02 00 01 EC 9E

Meaning Slv. Fn. Reg. ID Reg. Cnt DC The Data Chk. Sum

Receive 02 10 2A FC 00 01 C9 D2


MODBUS Action 1 of 1: Write value of the clearance code (0x0001) to MODBUS register 11,004

Transmit 00 00 00 00 00 09 0A 10 2A FC 00 01 02


Transmit 00 01

Meaning The Data

Receive 00 00 00 00 00 06 0A 10 2A FC 00 01


Result: Event cleared from the Historical Event Log. All associated data is no longer accessible.

Special Notes: If you wish to just accept the selected event, use the acceptance code 0x0000 To clear all events in the Historical Event Log, write any 16-bit value to MOBUS register 12,001


7955 2540 (CH07/BC) Page 7.37

7.11 Archive access over a MODBUS network This Section demonstrates how a MODBUS Master/Ethernet Client can access archives of a 7955 MODBUS Slave/Ethernet Server. Refer to Chapter 9 if an explanation of Data Archiving is required.

7.11.1 Introduction Information from Archives is retrievable through the map of MODBUS registers associated with ‘Virtual Address 4’ (base address + offset of 4).

Worked examples in Section 7.11.2 are provided to demonstrate the correct method for (1) selecting an archive by type, (2) selecting a snapshot in that archive and (3) retrieving values from that snapshot

Every example features objectives, actions, and a result analysis.





















Page 7.38 7955 2540 (CH07/BC)


A base address of “01” (for MODBUS) and “09” (for MODBUS/TCP) has been assumed for our examples. Objectives: 1. Select an archive

2. Find out how many snapshots are stored in that archive

3. Select a snapshot within that archive.

4. Retrieve values from that archive Step 1 is to select an archive by type and then, optionally, verify it has been selected MODBUS Action 1 of 2: Select the Interval Archive by writing 0x02 to MODBUS register number 999

Transmit 05 10 03 E7 00 01 02 00 02 31 86


Receive 05 10 03 E7 00 01 B0 3E

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk. Sum MODBUS/TCP Action 1 of 2: Select the Interval Archive by writing 0x02 to MODBUS register 999

Transmit 00 00 00 00 00 09 0D 10 03 E7 00 01 02

Meaning Transact ID Protocol ID Length UI+4 Fn. Reg. ID Reg. Cnt DC

Receive 00 02

Meaning The Data

Receive 00 00 00 00 00 0D 10 03 E7 00 01

Meaning Transact ID Protocol ID Length UI+4 Fn. Reg. ID Reg. Cnt Result: Reply indicates that the request was successful Special Note: Codes – 0x0000 (Alarm Triggered Archive), 0x0001 (Daily Archive), 0x0003 (Manual Trigger Archive) MODBUS Action 2 of 2: Verify the Archive selection by reading from MODBUS register number 999

Transmit 05 03 03 E7 00 01 35 FD


Receive 05 03 02 00 02 C8 45

Meaning Slv. Fn. DC The Data Chk. Sum MODBUS/TCP Action 2 of 2:

Verify the Interval Archive selection by reading from MODBUS register number 999

Transmit 00 00 00 00 00 06 0D 03 03 E7 00 01


Receive 00 00 00 00 00 05 0D 03 02 00 02

Meaning Transact ID Protocol ID Length UI+4 Fn. DC The Data Result: Reply indicates by type code 0x0002 that the Interval Archive has been selected


7955 2540 (CH07/BC) Page 7.39

Step 2 is to find how many snapshots are stored in the selected archive


Read MODBUS register 39,999

Transmit 05 03 9C 3F 00 01 9B D2


Receive 05 03 02 00 07

Meaning Slv. Fn. DC The Data


Read MODBUS register 39,999

Transmit 00 00 00 00 00 06 0D 03 9C 3F 00 01


Receive 00 00 00 00 00 05 0D 03 02 00 07


Result: There are presently 7 (0x0007) snapshots in the selected archive

Step 3 is to select a snapshot from the selected archive and then, optionally, verify it has been selected


Select newest snapshot the Archive by writing 0x0000 to MODBUS register 1000

Transmit 05 10 03 E8 00 01 02 00 00 B0 B8


Receive 05 10 03 E8 00 01 80 3D



Select newest snapshot the Archive by writing 0x0000 to MODBUS register 1000

Transmit 00 00 00 00 00 09 0D 10 03 E8 00 01 02

Meaning Transact ID Protocol ID Length UI+4 Fn. Reg. ID Reg. Cnt DC

Transmit 00 00

Meaning The Data

Receive 00 00 00 00 00 06 0D 10 03 E8 00 01


Result: Reply indicates that the request was successful

Special Note: This snapshot selection will not be reflected in archive parameters displayed within the menu system Other selection codes: 0x0001 (oldest snapshot), 0x0002 (2nd oldest snapshot), etc.


Page 7.40 7955 2540 (CH07/BC)


Check on snapshot selection by reading from MODBUS register number 1000

Transmit 05 03 03 E8 00 01 05 FE


Receive 05 03 02 00 00 49 84



Check on snapshot selection by reading from MODBUS register number 1000

Transmit 00 00 00 00 00 06 0D 03 03 E8 00 01


Receive 00 00 00 00 00 05 0D 03 02 00 00

Meaning Transact ID Protocol ID Length UI+4 Fn. DC The Data Result: Reply data 0x0000 indicates that the newest (latest) snapshot is selected

Special Note: This snapshot selection will not be reflected in archive parameters displayed within the menu system Other selection codes: 0x0001 (oldest snapshot), 0x0002 (2nd oldest snapshot), etc.

Step 4 is to retrieve the newest snapshot value from the first parameter programmed into the archive list

MODBUS Action 2 of 2: Retrieve first parameter attributes by reading MODBUS register 40000

Transmit 05 03 9C 40 00 02 EA 0B


Receive 05 03 04 06 04 FF 04 BE 89


MODBUS/TCP Action 2 of 2: Retrieve first parameter attributes by reading MODBUS register 40000

Transmit 00 00 00 00 00 06 0D 03 9C 40 00 02


Receive 00 00 00 00 00 07 0D 03 04 06 04 FF 04 Meaning Transact ID Protocol ID Length UI+4 Fn. DC The Data

Result: 0x06 = Data Type ‘6’ – IEEE 32-bit floating-point value 0x04 = Data Size – Parameter value stored in 4 bytes 0xFF = Status – No Status Attribute 0x04 = Units of measurement group 4 – Volumetric units

Special Notes: The order of this data packet is unaffected by the ‘word order’ mode. Other MODBUS registers: 40001 (= 2nd. listed parameter), 40002 (= 3rd. listed parameter), etc.


7955 2540 (CH07/BC) Page 7.41


Retrieve value by reading MODBUS register 2000

Transmit 05 03 07 D0 00 02 C5 02


Receive 05 03 04 00 0D 46 87 5C 32


MODBUS/TCP Action 2 of 2: Retrieve value by reading MODBUS register 2000

Transmit 00 00 00 00 00 06 0D 03 07 D0 00 02


Receive 00 00 00 00 00 07 0D 03 04 00 0D 46 87 Meaning Transact ID Protocol ID Length UI+4 Fn. DC The Data

Result: 0x000D4687 is the hexadecimal value for 870,023 (m3)

Special Note: Other MODBUS registers: 2001 (=2nd. listed parameter), 2002 (=3rd. listed parameter), etc.


Page 7.42 7955 2540 (CH07/BC)

PEER-TO-PEER COMMUNICATIONS

(CHAPTER 7 ADDENDUM ‘A’)

Chapter 7(a) Peer-To-Peer Communications Software Version 2540, Issue 2.30.00 (or higher)

Page 7a.2 Issue: AB

ABOUT THIS ADDENDUM

7a.1 What is the purpose if this addendum? This addendum has been written to provide a guide to the software support for peer-to-peer MODBUS network communications. To use this guide effectively, it is essential to be familiar with the 7955 keypad functions, moving around the menu system and editing. (Chapter 5 can help with this)

The data necessary for configuring a measurement/feature can be found in separate parts of the menu structure. A notation has been used as a short method of explaining how to move from the present menu to another menu.

As an example, the notation of <“Configure”>/<“Flow rate”> translates into these steps:

Step 1: Press the MAIN-MENU key

Step 2: Use the DOWN-ARROW (‘V’) key to scroll through pages until the word “Configure” is seen.

Step 3: Press the blue (letter) key that is alongside the word “Configure”.

Step 4: Use the DOWN-ARROW key to scroll through pages until the word “Flow rate” is seen.

Step 5: Press the blue (letter) key that is alongside the word “Flow rate”. Sometimes, it is convenient to use the MAIN-MENU key (especially if lost). However, use of the BACK-ARROW key is a much more common method of returning to a menu level. Note: The menu structure will vary in other software versions and releases.

Software Version 2540, Issue 2.30.00 (or higher) Chapter 7(a) Peer-To-Peer Communications

Issue: AB Page 7a.3

PEER-TO-PEER COMMUNICATIONS INTRODUCTION

7A.2 FEATURE: 7955 COMMUNICATION OF PARAMETERS USING PEER-TO-PEER LISTS What to do: • An overview is in Section 7a.2.1…………………….……………. Page 7a.3 • A list of configuration instructions is in Section 7a.2.2…..…….. Page 7a.5

7A.2.1 WHAT IS THE PURPOSE OF THIS FEATURE? This feature is typically used when a ‘Header’ Flow Computer must send various measurements (e.g. pressure, temperature, etc.) over a MODBUS protocol network to one or more ‘Stream’ Flow Computers. The Flow Computer network can be a mixture of members from the 7955.

USE OF THE MODBUS PROTOCOL In MODBUS protocol terms, a ‘Header’ Flow Computer is usually given the role of a MODBUS Master device. It has the responsibility for the peer-to-peer transmission of measurement values during every machine cycle. The ‘Stream’ Flow Computers are all MODBUS Slave devices and they are the recipients of peer-to-peer transmissions.

When an RS-232 point-to-point network is the vehicle for this feature…

A 7955 Master device continuously broadcasts values of peer-to-peer nominated parameters directly to the database of a single 7955 Slave device. The two MODBUS devices can be wired together via any serial port supporting RS-232 standard. A peer-to-peer topology is shown in Figure 2on page 7a.3.

When an RS-485 multiple-drop network is the vehicle for this feature…

A 7955 Master device continuously broadcasts values of peer-to-peer nominated parameters to a maximum of sixteen 7955 MODBUS slaves. The 7955 MODBUS devices can be wired together via any serial port supporting the RS-485 standard. A peer-to-peer topology is shown in Figure 3on page 7a.3

At present, peer-to-peer communications will operate through one serial port. Configuring another serial port of the ‘Header’ 7955 to function as a Master device and connecting it to a duplicate MODBUS network will cause unpredictable results.

THE PEER-TO-PEER LISTS On the 7955 Master there are two peer-to-peer lists 1 for compiling a collection of up to 40 measurement parameters (7955 database locations) in total. The list is simply a look-up reference for the Master, when preparing transmissions, and is programmed with database location IDs. 2

Figure 1 shows how an individual peer-to-peer list comprises of entries (menu data pages) for nominating from 1 up to 20 parameters. Each list entry requires a programmed source – a database location ID on the 7955 Master device - and a programmed destination – a database location ID on the 7955 Slave devices.

Figure 1: Peer-To-Peer List Anatomy

661 661

Source(Location IDs)

Destination(Location IDs)

PEER-TO-PEER LIST(with practice values)

256 662

(Off) (Off)

"IndicatedVolume Rate"

(Off) (Off)"Actual CycleTime"


"GrossVolume Rate"

01

02

03

20

01

02

03

20

1 These lists are wholly independent of the High Speed Lists that are set-up on one (or more) 7955 MODBUS slaves for access by

non-7955 MODBUS Master devices. 2 To find out the database location ID for any parameter, navigate the menu system to the applicable menu data page and then

press the ‘a’ soft-key once. The 4-digit database location ID is then displayed on the fourth line of the LCD display.


Page 7a.4 Issue: AB

INTRODUCTION PEER-TO-PEER COMMUNICATIONS

Each 7955 Slave device is allocated one of the two lists. This is a user-selection and is made when defining slaves whilst setting up the 7955 Master device. Once lists are programmed, peer-to-peer operations are commenced on the 7955 Master by a selecting an “Enable” option (‘soft-command’) through a menu data page. For each correctly listed parameter, a value is then read from the database, incorporated into a MODBUS ‘write’ command message and transmitted from the 7955 Master device to the database on designated 7955 Slave devices. All peer-to-peer lists, in use, are processed in full during a single machine cycle. This is repeated once every cycle until peer-to-peer operations are stopped by a “disable” ‘soft-command’. In a network of two 7955 Flow Computers – a Master device and a Slave device, the Master is able to detect all failures to communicate with the slave and it raises a system alarm. With one slave, every MODBUS (‘write’) command message is explicitly addressed and that solicits a response from that slave. The absence of a response after a period (of retries) is how the Master detects a failure 3. In a network of multiple slaves, MODBUS ‘write’ command messages use an all-slave broadcast address, which does not solicit any response and, therefore, the Master does not detect a communication failure. In this case, the system alarm is not raised. When the system alarm can not be cleared without it re-appearing during the next machine cycle, there are continuous communication failures. It is advisable to temporarily halt peer-to-peer operations, clear all related alarms and investigate (and correct) the difficulty before resuming.

Figure 2: Peer-To-Peer - Basic RS232 Arrangement

LIST ONE

7955 MODBUSMaster Device

LIST TWO

DATABASEDATABASE7955 MODBUSSlave Device 1P1 P2

RS-232

MODBUSCommands

LINK

LogicalLink

Figure 3: Peer-To-Peer - Basic RS485 Arrangement

LIST ONE

7955 MODBUSMaster Device

LIST TWO

DATABASE

DATABASE

DATABASE

DATABASE

7955 MODBUSSlave Device 1



P2

P3

P2

P3

RS-485LINK

MODBUSCommands

LogicalLink

3 This type of failure is normally the symptom of a faulty/unsuitable cable, incorrect set-up of communication parameters or the

absence of a physical connection to a MODBUS network.

Software Version 2540, Issue 2.30.00 (or higher) Chapter 7(a) Peer-To-Peer Communications

Issue: AB Page 7a.5

PEER-TO-PEER COMMUNICATIONS INSTRUCTIONS

7a.2.2 Configuring and activation instructions Follow these instructions to configure and activate peer-to-peer communications…

1. Ensure that 7955 Flow Computers are already interconnected to form a MODBUS network Guidance on the necessary RS-232 or RS-485 wiring 4 connections is in Chapter 7. Several peer-to-peer arrangements are shown on page 7a.4.

2. Program a 7955 Flow Computer to be the MODBUS master device

(2a) Navigate to this menu: <”Configure”>/<”Other Parameters”>/<”Communications”>/<”Ports”>

(2b) Select the menu for the serial port that is connected to the MODBUS network

(2c) Program the basic communications parameters for that serial port, as shown in Table 1. Some localised menu searching is required.

Table 1: Basic Serial Port Communication Parameters

Menu Data * Instructions and Comments

Comms port owner Select the option with “Modbus master” as the description

Port Baud rate Select a rate that is agreed for the 7955 Master device and all the slaves devices

Port char format Select a character transmission format (as agreed for the MODBUS network)

Port handshaking Select either “None” or “XonXoff” unless the cable (wiring) supports “CTS/RTS”

Port RS232 / 485 Select the signalling standard for the MODBUS network ** P Modbus word order *** Not applicable to the 7955 Master device

Port Modbus mode Select the option that is compatible with the other MODBUS network devices.

P MODB slave addr *** Not applicable to a 7955 Master device. The existing setting does not affect it. P Modbus features Not applicable to a 7955 Master device. The existing setting does not affect it.

P long reg access *** Choose either single register or multiple register formatted MODBUS commands

P MODB precision *** Choose a precision option that is agreed for the Master and all the slaves devices * On-screen version of a menu data page descriptor includes a digit to identify the directly associated serial port

** A 7955 may perform ‘warm restarts’ if it is configured to use RS-232 when connected to an RS-485 network

*** Abbreviations: “P ” = Port, “reg” = register, “addr” = address, “char” = character, “MODB” = MODBUS

(2d) Navigate to this menu: <”Configure”>/<”Other Parameters”>/<”Communications”>/<”Modbus master”>/<”Peer to peer”>

(2e) Program the peer-to-peer lists

Peer List One Menu: <Configure”>/…<”Modbus master”>/<”Peer to Peer”>/<”Peer list 1”> Peer List Two Menu: <Configure”>/…<”Modbus master”>/<”Peer to Peer”>/<”Peer list 2”>

When programming a list, it is very important to use the first available (unused) entry and to not leave gaps. This will avoid inadvertently shortening the list.

Programming a valid location number for a source will immediately result in the number changing to the parameter descriptor. The destination does not do this because the edited location number stays displayed as the edited number. Editing a location number for a parameter that does not exist is responded with a “*** ERROR ***” message appearing briefly and the original setting is then restored. By default, destinations (location IDs) are automatically synchronised with the corresponding sources. This is ideal for when Flow Computers are running the same software release. However, the source and destination (IDs) do not have to be the same. For each list, there is a peer-to-peer configuration

4 To avoid the risk of ‘warm restarts’, it is advisable to pre-set the signalling standard – RS-232 or RS-485 – for 7955 serial ports

before establishing the physical connections.

CONNECTING MORE THAN ONE SERIAL PORT TO THE A PEER-TO-PEER MODBUS NETWORK WILL CAUSE UNPREDICTABLE RESULTS


Page 7a.6 Issue: AB

INSTRUCTIONS PEER-TO-PEER COMMUNICATIONS

parameter, <PeerLn dest/src>, to stop the synchronising action and enable IDs to be different. This feature allows 7955 slave devices to run releases other software versions and still get updates from the Master device. Re-enabling the synchronising will immediately trigger the overwriting of all destination IDs with the source IDs, losing the destination IDs forever.

Values go directly into the 7955 database of a slave unless serial communications is prohibited. Security parameters for serial communications are found within <”Configure”>/<”Other parameters”>/<”Security”>.

(2f) Inform the 7955 Master about all 7955 slave devices on the network

(Note: Start by programming details of your first slave using parameters within the “Device 1” menu)

Menu Data * Instructions and Comments Slave device func ** Select the option with “Peer” as the description.

Slv device port no ** Select the serial port that is connected to same the network as the slave Slv device address ** Use “0” if there are multiple slaves. Otherwise, use the address of the slave

Device word swap Not applicable to the 7955 but may be needed by protocol listening devices

Device precision Use a precision option that is the same as the 7955 MODBUS Master

Device peer list Select the option that corresponds to one of the two peer-to-peer lists

* On-screen version of menu data descriptor includes a digit to identify the directly associated serial port

** Abbreviations: “Slv” = Slave, “func” = Function, “port no” = port number

3. Program each remaining 7955 to be a MODBUS slave device


(3b) Select a menu that corresponds to the serial port that is connected to the RS-485 network

(3c) Set-up basic communications parameters…


Comms port owner Select the option with “Modbus slave” as the description

Port Baud rate Select a rate that is compatible with the other MODBUS network devices Port char format *** Select a rate that is compatible with the other MODBUS network devices

Port handshaking Select the same option as used for the 7955 Master device

Port RS232 / 485 Select the signalling standard for the MODBUS network ** P Modbus word order *** Select the option that is compatible with the other MODBUS network devices

Port Modbus mode Select the option that is compatible with the other MODBUS network devices P MODB slave addr *** Edit a value that does not conflict with other MODBUS network devices

P Modbus features *** Not applicable to peer-to-peer operations P long reg access *** Select the same option as used for the 7955 Master device P MODB precision *** Select the same option as used for the 7955 Master device

* On-screen version of menu data descriptor includes a digit to identify the directly associated serial port


*** Abbreviations: “P ” = Port, “reg” = register, “addr” = address, “char” = character, “MODB” = MODBUS 4. Start peer-to-peer communications at the 7955 Master device

(4a) Navigate to: <”Configure”>/<”Other Parameters”>/<”Communications”>/<”Modbus master”>

(4b) Locate the menu data page with “Peer enable” on-screen

(4c) Select the “Enable” soft-command (option)

Once enabled, it is advisable to stop (deactivate) peer-to-peer communications prior to adjusting the communications set-up. Once changes have been made, re-enable the peer-to-peer function with step 4.


HIGH-SPEED LIST COMMUNICATIONS

(CHAPTER 7 ADDENDUM ‘B’)

Chapter 7(b) HSL Communications Software Version 2540, Issue 2.30.00 (or higher)

Page 7b.2 Issue: AB

ABOUT THIS ADDENDUM

7b.1 What is the purpose if this addendum? This addendum has been written to provide a guide to the software support for HSL - High Speed List – communications over a MODBUS protocol network. To use this guide effectively, it is essential to be familiar with the 7955 keypad functions, moving around the menu system and editing. (Chapter 5 can help with this)

The data necessary for configuring a measurement/feature can be found in separate parts of the menu structure. A notation has been used as a short method of explaining how to move from the present menu to another menu.


Step 1: Press the MAIN-MENU key

Step 2: Use the DOWN-ARROW (‘V’) key to scroll through pages until the word “Configure” is seen.

Step 3: Press the blue (letter) key that is alongside the word “Configure”.

Step 4: Use the DOWN-ARROW key to scroll through pages until the word “Flow rate” is seen.

Step 5: Press the blue (letter) key that is alongside the word “Flow rate”. Sometimes, it is convenient to use the MAIN-MENU key (especially if lost). However, use of the BACK-ARROW key is a much more common method of returning to a menu level. Note: The menu structure will vary in other software versions and releases.

Software Version 2540, Issue 2.30.00 (or higher) Chapter 7(b) HSL Communications

Issue: AB Page 7b.3

INTRODUCTION HIGH-SPEED LIST COMMUNICATIONS

7B.2 FEATURE: COMMUNICATION OF PARAMETER DATA USING HIGH-SPEED LISTS • An overview is in Section 7b.2.1…………..…………………………….. Page 7b.2 • A list of configuration instructions is in Section 7b.2.2………..……... Page 7b.9 • A guided example in Section 7b.2.3……………………..…...………… Page 7b.12 • Wonderware compatibility notes are in Section 7b.3………….……….. Page 7b.18

7b.2.1 WHAT IS THE PURPOSE OF THIS FEATURE? This feature is typically used when a MODBUS Master device 1 must get parameter data from a 7955 Flow Computer, where both are attached to the same MODBUS protocol network.

High-speed list communications facilitate the quick collection and transmission of data from up to 300 user-nominated parameters. This is achieved by using just a small quantity of MODBUS protocol messages. It would otherwise require an exchange of hundreds of messages.

The 7955 Flow Computer also helps by collecting all the data of nominated (listed) parameters from its’ database and keeping it ‘local’. This activity is completed during every machine cycle. Keeping parameter data ‘locally’ allows faster data access, allowing the 7955 to service requests from a Master device as quickly as possible. Hence, the term of ‘high-speed lists’.

There are two aspects to high-speed list communications:

• the MODBUS protocol (network arrangements, communication parameters and message exchanges) • a list of parameters (i.e. 7955 database locations) and

Read about each aspect in the sections that follow this overview and then look at the setting-up instructions and the guided example.

USE OF THE MODBUS PROTOCOL In MODBUS protocol terms, the MODBUS Master device is likely to be a supervisory system. The Master device is responsible for acquiring parameter data through an exchange of MODBUS protocol messages with one ore more a MODBUS networked slave devices. The 7955 Flow Computer is the MODBUS slave device, supporting RS-485 and RS-232 signalling standards.

When an RS-232 point-to-point network is the vehicle for this feature…

A Master device can request parameter data from one 7955 slave device. The two MODBUS devices can be wired together via any serial port supporting RS-232 Standard. (See Figure 1 on page 7b.3)

When an RS-485 multiple-drop network is the vehicle for this feature…

A Master device can request parameter data from one or more 7955 slaves. The 7955 MODBUS slave devices can be wired together via any serial port supporting the RS-485 Standard. (See Figure 2 on page 7b.4)

Figure 1: High Speed List Overview (RS-232 Example)

High Speed List One(Virtual Slave 2)

7955 MODBUSSlave Device

APPLICATIONDATABASE

MODBUSMaster Device

P1 P2RS-232

MODBUSMessages

LINK

Read/WriteDatabase

Operations

High Speed List Two(Virtual Slave 3)

Direction of flow(HSL Data)

1 This MODBUS Master device cannot be a 7955 Flow Computer. Direct communication of a parameter value between 7955 Flow

Computers can be performed using the “Peer-To-Peer Lists” feature.


Page 7b.4 Issue: AB

HIGH-SPEED LIST COMMUNICATIONS INTRODUCTION

Figure 2: High Speed List Overview (RS-485 Example)

High Speed List 1(Virtual Slave '2')


APPLICATION

DATABASE

MODBUS Master Device

P2

SerialPort

RS-485Link

MODBUSMessages

Read/WriteOperations

Direction of flow(HSL Data)



DATABASEP3



Figure 3: High Speed List Activity within 7955 Slave Devices

LIST ONE


LIST TWO

DATABASECopying Activity

Every Cycle

Loc ID: 0661450.015V

S Live

1

Loc ID: 0662448.011V

S Live

2

Loc ID: 0000-V

S -

3

Loc ID: 0000-V

S -

50

Loc ID: 0661450.015V

S Live

Loc ID: 0662448.011V

S Live

Loc ID: 0663-V

S -

7955 DATABASE

HIGH SPEED LIST ONE

Figure 4: Parameter List Block Organisation

HIGH SPEED LIST TWO

661 0718

BLOCK A(Location IDs)

HIGH-SPEED LIST ONE

662 0595

(Off) (Off)

IndicatedVolumeflow rate

(Off) 1548GrossVolumeflow rate

01

02

03

50

01

02

03

50

(Off)(Off)

(Off)

(Off)

01

02

03

50

BLOCK B(Location IDs)

BLOCK C(Location IDs)

(Off) = Unused Entry

2048 (Off)

BLOCK D(Location IDs)

2111 (Off)

(Off) (Off)

PrimeDynamicViscosity

(Off) (Off)PrimeKinematicViscosity

01

02

03

50

01

02

03

50

(Off)(Off)

(Off)

(Off)

01

02

03

50

BLOCK E(Location IDs)

BLOCK F(Location IDs)



Issue: AB Page 7b.5


THE HIGH-SPEED PARAMETER LIST On 7955 slaves there are two individual lists 2 for nominating the parameters – labelled as “High-speed List 1” and “High Speed List 2” within the communications area of the menu system. Each list has the capacity for nominating up to 150 parameters, organised into three blocks of 50 parameters. Figure 4 on page7b.4 illustrates the three block structure for both lists. The figure shows that blocks are set-up on an individual basis. Parameters are nominated using their own unique database location identification (ID) number. Each entry in a block has a dedicated menu data page for editing in a location ID.

The parameter list is primarily for the 7955 slave device to extract data of specific parameters from its’ database during every machine cycle. All extracted data is stored ‘locally’ for faster and more efficient data access. It is then accessible only to a Master device by means of MODBUS ‘read’ command messages. Figure 3 on page 7b.4 illustrates the process.

MODBUS ‘read’ command messages must be addressed to either virtual slave ‘2’ or virtual slave ‘3’ through any MODBUS slave configured port. Virtual slave addressing is explained in Chapter 7.

MODBUS Address Information Available

Virtual Slave ‘2’ High-speed List One

Virtual Slave ‘3’ High-speed List Two

The register map at each virtual slave is initially in a pre-set format but it can be individually re-organised to suit applications on the Master device. There are several basic styles available for selection. Follow the links in Table 1 to get a graphical overview of default register maps for each basic style. You will also get to see how the blocks of a parameter list are linked to a register map.

Table 1: Links to graphical overviews of high-speed lists and register maps

Styles Graphical Representation

Old Style (Legacy) * See Figure 5 on page 7b.6

Grouped See Figure 6 on page 7b.7

Ungrouped See Figure 7 on page 7b.8

* As found in 7955 software released before the year 2000

2 These lists are wholly independent of the peer-to-peer lists that are set-up on a 7955 MODBUS Master device.


Page 7b.6 Issue: AB


Figure 5: Default Register Mappings for "Old Style" High-speed Lists 1 and 2

Values

Location IDs

Status

1001

11001

21001Types and Sizes

Full Attributes

31001

41001

BLOCK 'E' SECTIONS(VIRTUAL SLAVE 3 REGISTER MAP)

Block D Block E Block FHIGH-SPEED LIST 2

HSL-2 BLOCK E

HSL ONE

HSL-2 BLOCKS

HSL TWO

1050

11050

HIGH-SPEEDLISTS

21050

31050

41050

Values

Location IDs

Status

1

10001


Full Attributes

30001

40001

BLOCK 'D' SECTIONS(VIRTUAL SLAVE 3 REGISTER MAP)

HSL-2 BLOCK D

50

10050

20050

30050

40050

Values

Location IDs

Status

2001

12001


Full Attributes

32001

42001

HSL-2 BLOCK F

2050

12050

22050

32050

42050

BLOCK 'F' SECTIONS(VIRTUAL SLAVE 3 REGISTER MAP)

VIRTUAL SLAVE 2

VIRTUAL SLAVE 3

Block A Block B Block C HIGH-SPEED LIST 1HSL-1 BLOCKS

Values

Location IDs

Status

1001

11001


Full Attributes

31001

41001

BLOCK 'B' SECTIONS(VIRTUAL SLAVE 2 REGISTER MAP)

HSL-1 BLOCK B

1050

11050

21050

31050

41050

Values

Location IDs

Status

1

10001


Full Attributes

30001

40001

BLOCK 'A' SECTIONS(VIRTUAL SLAVE 2 REGISTER MAP)

50

10050

20050

30050

40050

Values

Location IDs

Status

2001

12001


Full Attributes

32001

42001

BLOCK 'C' SECTIONS(VIRTUAL SLAVE 2 REGISTER MAP)

2050

12050

22050

32050

42050

HSL-1 GroupedStart Register = 0

HSL-1 BLOCK A HSL-1 BLOCK C


51 - 1000

are unused1051 - 2000

are unused

2051 - 10000are unused

2051 - 10000are unused

51 - 1000

are unused 1051 - 2000

are unused

BLOCK APARAMETER LIST

0102

50

BLOCK BPARAMETER LIST

0102

50

BLOCK CPARAMETER LIST

0102

50

BLOCK DPARAMETER LIST

0102

50

BLOCK EPARAMETER LIST

0102

50

BLOCK FPARAMETER LIST

0102

50


Issue: AB Page 7b.7


Figure 6: Default Register Mappings for "Grouped" High-speed Lists 1 and 2

Values

Location IDs

Status

50

200

350Types and Sizes

Full Attributes

500

650



HSL-2 BLOCK E

HSL ONE

HSL-2 BLOCKS

HSL TWO

99

249

HIGH-SPEEDLISTS

399

549

699

Values

Location IDs

Status

0

150

300Types and Sizes

Full Attributes

450

600


HSL-2 BLOCK D

49

199

349

499

649

Values

Location IDs

Status

100

250

400Types and Sizes

Full Attributes

550

700

HSL-2 BLOCK F

149

299

449

599

749


VIRTUAL SLAVE 2

VIRTUAL SLAVE 3


Values

Location IDs

Status

50

200

350Types and Sizes

Full Attributes

500

650


HSL-1 BLOCK B

99

249

399

549

699

Values

Location IDs

Status

0

150

300Types and Sizes

Full Attributes

450

600


49

199

349

499

649

Values

Location IDs

Status

100

250

400Types and Sizes

Full Attributes

550

700

BLOCK 'C' SECTIONS (VIRTUALSLAVE 2 REGISTER MAP)

149

299

449

599

749





0102

50


0102

50


0102

50


0102

50


0102

50


0102

50


Page 7b.8 Issue: AB


Figure 7: Default Register Mappings for "Ungrouped" High-speed Lists 1 and 2

Values

Location IDs

Status

250

300

350Types and Sizes

Full Attributes

400

450



HSL-2 BLOCK E

HSL ONE

HSL-2 BLOCKS

HSL TWO

299

349

HIGH-SPEEDLISTS

399

449

499

Values

Location IDs

Status

0

50

100Types and Sizes

Full Attributes

150

200


HSL-2 BLOCK D

49

99

149

199

249

Values

Location IDs

Status

500

550

600Types and Sizes

Full Attributes

650

700

HSL-2 BLOCK F

549

599

649

699

749


VIRTUAL SLAVE 2

VIRTUAL SLAVE 3


Values

Location IDs

Status

250

300

350Types and Sizes

Full Attributes

400

450


HSL-1 BLOCK B

299

349

399

449

499

Values

Location IDs

Status

0

50

100Types and Sizes

Full Attributes

150

200


49

99

149

199

249

Values

Location IDs

Status

500

550

600Types and Sizes

Full Attributes

650

700

BLOCK 'C' SECTIONS(VIRTUAL SLAVE 2 REGISTER MAP)

549

599

649

699

749





0102

50


0102

50


0102

50


0102

50


0102

50


0102

50


Issue: AB Page 7b.9

HIGH-SPEED LIST COMMUNICATIONS INSTRUCTIONS

7b.2.2 Configuring and Activation Instructions

Follow these instructions to configure and activate high-speed list communications: 1. Ensure that 7955 Flow Computers are already interconnected to form a MODBUS network

Guidance on the necessary RS-232 or RS-485 wiring 3 connections is in Chapter 7.

2. Program a 7955 Flow Computer to be the MODBUS slave device


(2b) Select the menu that is appropriate for the serial port that is connected to the MODBUS network

(2c) Program the basic communications parameters for that serial port, as shown in Table 2. Some localised menu searching is required.



Comms port owner Select the option with “Modbus slave” as the description Port Baud rate Select a rate that is agreed for the Master device and all the 7955 slaves devices

Port char format Select a character transmission format (as agreed for the MODBUS network) Port handshaking Select either “None” or “XonXoff” unless the cable (wiring) supports “CTS/RTS” Port RS232 / 485 Select the signalling standard for the MODBUS network **

P Modbus word order *** Select an option that is compatible with the Master device Port Modbus mode Select the option that is compatible with the other MODBUS network devices.

P MODB slave addr *** Program the base address of this slave P Modbus features Select an option that includes “L1”/“List1” for HSL-1 and “L2”/“List2” for HSL-2

P long reg access *** Choose to accept either the single or multiple register MODBUS command format

P MODB precision *** Select a precision option that is compatible with the Master device * On-screen version of a menu data page descriptor includes a digit to identify the directly associated serial port


*** Abbreviations: “P ” = Port, “reg” = register, “addr” = address, “char” = character, “MODB” = MODBUS

3. Program High Speed List ‘1’ (if applicable)

(3a) Navigate to this menu: <”Configure”>/<”Other Parameters”>/<”Communications”>/<”Modbus slave”>

(3b) Select the menu that is appropriate for HSL-1

(3c) Program the configuration parameters for HSL-1, as guided in Table 3

Table 3: HSL-1 Configuration Parameters (Part One)

Menu Data Instructions and Comments

List 1 word order • This selection overrides the serial port setting

List 1 block layout • Select default register map organisation: “Old Style”, “Grouped” or “Ungrouped” * L1 grouped start reg • Program the number of the first register space for the complete register map **

* See pages 7b.6, 7b.7 and 7b.8 for a graphical view of the default register map for each selectable style

(3d) View/Edit the number of the first register for each register map section in ‘Block A’ (if applicable)

Note: This step does not apply when the “Old Style” (legacy) register map layout is chosen in step 3c Table 4 lists descriptors for identifying the menu data pages associated with viewing and editing the existing register map in ‘Block A’. Alongside the descriptors are default settings for every selectable block layout style.

3 To avoid the risk of ‘warm restarts’, it is advisable to pre-set the signalling standard – RS-232 or RS-485 – for 7955 serial ports

before establishing the physical connections.


Page 7b.10 Issue: AB


Editing of the start registers is only required when the default settings form a register map that is unsuitable for the application on the Master device.

Table 4: Configuration Parameters for Section Start Registers of HSL-1 Block A

Menu Data (as displayed)

Default Start Registers (“Old Style” mapping)

Default Start Registers (“Grouped” mapping)

Default Start Registers (“Ungrouped” mapping)

L1A vals start reg 1 0 0 L1A locs start reg 10001 150 50

L1A types start reg 20001 300 100 L1A status start reg 30001 450 150 L1A attrs start reg 40001 600 200

Note: Also see Table 5 and Table 6 for the default settings of the other HSL-1 blocks

(3e) View/Edit the number of the first register for each register map section in ‘Block B’ (if applicable)

Note: This step does not apply when “Old Style” (legacy) register map has been chosen in step 3c

Table 5 lists descriptors for identifying the menu data pages associated with viewing and editing the present register map of ‘Block B’. Alongside the descriptors are the default settings for every selectable block layout style.


Table 5: Configuration Parameters for Section Start Registers of HSL-1 Block B

Menu Data * (as displayed)

Default Start Registers (“Old Style” map)

Default Start Registers (“Grouped” map)

Default Start Registers (“Ungrouped” map)

L1B vals start reg 1001 50 250 L1B locs start reg 11001 200 300

L1B types start reg 21001 350 350 L1B status start reg 31001 500 400 L1B attrs start reg 41001 650 450

Note: Also see Table 4 and Table 6 for the default settings of the other HSL-1 blocks

(3f) View/Edit the number of the first register for each register map section in ‘Block C’ (if applicable)

Note: This step does not apply when “Old Style” (legacy) register map has been chosen in step 3c Table 6 lists descriptors for identifying the menu data pages associated with viewing and editing the present register map of ‘Block C’. Alongside the descriptors are the default settings for every selectable block layout style.


Table 6: Configuration Parameters for Section Start Registers of HSL-1 Block C

Menu Data * (as displayed)

Default Start Registers (“Old Style” map)

Default Start Registers (“Grouped” map)

Default Start Registers (“Ungrouped” map)

L1C vals start reg 2001 100 500 L1C locs start reg 12001 250 550

L1C types start reg 22001 400 600 L1C status start reg 32001 550 650 L1C attrs start reg 42001 700 700

Note: Also see Table 4 and Table 5 for the default settings of other HSL-1 Blocks


Issue: AB Page 7b.11


(3g) Program the high-speed list with the location ID of each parameter to be made available to the Master

Table 7 lists the descriptors of the menu data pages for programming the ‘Block A’ partition with location IDs of up to 50 parameters. The menu data pages are easily located within the 7955 menu system under the <“Block A”> sub-menu.

Table 7: ‘BLOCK A’ Parameter Entries 1–50

Menu Data (as displayed) Purpose

DBM list 1A ptr 1 * BLOCK A PARAMETER LIST ENTRY 1

DBM list 1A ptr 2 * BLOCK A PARAMETER LIST ENTRY 2

: : DBM list1A ptr 50 * BLOCK A PARAMETER LIST ENTRY 50

* Abbreviation: “ptr” = pointer (a programming term)

The menu data pages for programming entries in ‘Block B’ and ‘Block C’ are easily located within the menu system under the <“Block B”> and <“Block C”> sub-menus. It is good practice to start with ‘Block A’ before progressing to ‘Block B’. Likewise, start with ‘Block B’ before progressing to ‘Block C’. It is not necessary to fully utilise a block before using another. When programming in location identification numbers (IDs), it is very important to use the first available (unused) entry and to not leave gaps. This will avoid inadvertently shortening the list. (See Figure 8)

Figure 8: Correct and Incorrect Programmed Parameter Lists

661 0718


HIGH SPEED LIST '1'(Programmed Correctly)

662 0595

(Off) (Off)


(Off) 1548"GrossVolume Rate"

01

02

03

50

01

02

03

50

(Off)(Off)

(Off)

(Off)

01

02

03

50




661 0718


(Off) (Off)

(Off) (Off)


662 0595"GrossVolume Rate"

01

02

03

50

01

02

03

50

(Off)(Off)

(Off)

(Off)

01

02

03

50




HIGH SPEED LIST '1'(Programmed Incorrectly)

Programming in a valid location number will immediately result in the number changing to the parameter descriptor. Editing a location number for a parameter that does not exist is responded with a “** ERROR **” message appearing briefly and the original setting is then restored.

4. Program High Speed List ‘2’ (if it is to be used )

Repeat steps 3a to 3g but this time it is for configuring HSL-2. (End of instructions)



HIGH-SPEED LIST COMMUNICATIONS GUIDED EXAMPLE

7b.2.3 Guided Example: Accessing a HSL over a MODBUS network This section is a practical guide to collecting parameter data from a 7955 MODBUS Slave through the high-speed list feature. For this guided example, High-speed List ‘1’ (HSL-1) has been used. What to do here: 1. Review the 7955 slave configuration

Table 9 and Table 10 (on page 7b.13) show configuration details for this guided example. These checklists should be used in conjunction with the “Instructions” section on page 7b.9.

MODBUS feature settings for the serial port have been chosen especially to obtain the MODBUS message sequences that are shown later. For a full list of configuration parameters for serial communications, please refer to the “Instructions” section on page 7b.9.

For the purpose of this guided example, instructions assume that the Master device is already set-up.

2. Review the MODBUS message sequences

MODBUS message sequences aim to show the best approach to accessing high-speed list parameter data through a MODBUS register map at a virtual slave address. For this guided example, the “Old Style” default register map has been used.

Every example features an objective, an action and a result…

Objective(s) For an example, the objective could be to read a value from two listed parameters.

Action(s) Actions consist of one or more ‘read’ and ‘write’ MODBUS protocol commands. They are represented in this documentation as tabulated hexadecimal values in sequence for transmission by the Master device. Expected replies from the 7955 MODBUS slave device are also shown as tabulated values.

Table 8 is a list of all the abbreviations of meanings that can appear with a sequence. Use them to distinguish the important elements of the message.

Result This is a brief analysis of the MODBUS slave response to an action. There may be a reference to additional information.

3. Experiment

Try out the examples and then adapt them to suit your requirements

Table 8 : Abbreviations for Interpreting Elements of Transmit and Receive Sequences

Abbreviation Meaning

Slv. Virtual slave address. It is 0x03 for this guided example.


Fn. Function code. E.g. 03 = Read multiple registers

Reg. Cnt Number of registers requested

Reg. ID MOBUS register number

DC Number of ‘data bytes’ in reply





GUIDED EXAMPLE HIGH-SPEED LIST COMMUNICATIONS

Table 9: HSL-1 Set-up for Guided Example

Menu Data (as displayed) Value/Option Comment

List 1 word order “Modbus default”

List 1 block layout “Old-style” The register map for this example is shown in Figure 9.

L1 grouped start reg 0 DBM list 1A ptr 1 0661 ID is for Indicated Volume flow rate DBM list 1A ptr 2 0662 ID is for Gross Volume flow rate DBM list 1A ptr 3 0000 ID is for “Off” - terminates the parameter list for Block A DBM list 1B ptr 1 0773 ID is for integer part of the Indicate Volume flow total DBM list 1B ptr 2 0772 ID is for fractional part of the Indicate Volume total DBM list 1B ptr 3 0779 ID is for integer part of the Gross Volume flow total DBM list 1B ptr 4 0778 ID is for fractional part of the Gross Volume flow total DBM list 1B ptr 5 0000 ID is for “Off” - terminates the parameter list for Block B DBM list 1C ptr 1 0000 ID is for “Off” - terminates the parameter list for Block C

Notes: 1. Metering totals are stored in the database in two parts. There is one database location for the integer part and

one database location for the fractional part. They are usually not displayed within the menu system. When communicating totals over MODBUS, transmit both the integer and fractional values. All totals displayed within the menu system are also database locations. However, they are not suitable for transmission.

2. Abbreviations: “L1” = ‘High-speed List 1’, “reg” = register, “DBM” = Database Manager, “ptr” = pointer

3. Location identification numbers (IDs) and descriptors may differ to those listed here if you are using a later software release

Table 10: Serial Port Set-up for Guided Example

Menu Data * Value/Option Comments

Comms port owner “Modbus slave” P Modbus word order Modbus default Port Modbus mode “RTU”

P MODB slave addr 1 • This is the base slave address

P Modbus features “Alarm+List1+List2” • Enables virtual slaves 1, 2 and 3

P long reg access “Single register” • Request 1 register per parameter

P MODB precision “Single” • Require 32-bit floating-point values

* Location descriptors may differ to those listed here if you are using a later software release

Figure 9: Register Map for Guided Example 1

Values

Location IDs

Status

1001

11001


Full Attributes

31001

41001

BLOCK 'B' SECTIONS(REGISTER MAP)

Block A Block B Block C

HIGH-SPEED LIST

HSL 1 BLOCK B

HSL ONEHSL BLOCKS

HSL TWO

1050

11050

HIGH-SPEEDLISTS

21050

31050

41050

Values

Location IDs

Status

1

10001


Full Attributes

30001

40001


HSL-1 BLOCK A

50

10050

20050

30050

40050

Values

Location IDs

Status

2001

12001


Full Attributes

32001

42001

BLOCK 'C' SECTIONS(REGISTER MAP)

HSL 1 BLOCK C

2050

12050

22050

32050

42050

51 - 1000

are unused1051 - 2000

are unused



HIGH-SPEED LIST COMMUNICATIONS GUIDED EXAMPLE MODBUS MESSAGE SEQUENCES: All transmit and receive sequences, shown here, demonstrate use of default word ordering, single precision (32-bit) data representation and ‘single register’ formatted commands. Transmitted messages are addressed to the second virtual slave (base slave address + 2) for access to the “Old style” default register map of High-speed List 1. (1a) Objective: Read values from all of the parameters listed in High-speed List One (HSL-1)

Action 1 of 3: Read two registers starting from MODBUS register 1 (Values Section, ‘Block A’)

Values expected in the reply are 3600.125 and 3546.123, both in base units of m3/hour.

Transmit 03 03 00 01 00 02 94 29

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk Sum

Receive 03 03 08 45 61 02 00 45 5D A1 F8 D7 88

Meaning Slv. Fn. D.C. The Data … The Data … The Data Chk sum

Result: • 45610200 is the 32-bit IEEE hexadecimal representation for 3600.125 (in base units of m3/hour) • 455DA1F8 is the 32-bit IEEE hexadecimal representation for 3546.123 m3/hour

Note: When using the single register mode, the number of registers to be read is the same as the number of parameters to be read from the associated block. This happens to be two for ‘Block A’ in this example.

Action 2 of 3: Read four registers starting from MODBUS register 1001 (Values Section, ‘Block B’)

Transmit 03 03 03 E9 00 04 94 5B

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk. sum

Receive 03 03 10 46 18 3C 00 3F 19 0A B1 46 15

Meaning Slv. Fn. D.C. The Data … The Data … The Data … The

Receive F4 00 3E E3 40 94 24 24

Meaning Data … The Data … … Chk. Sum

Result: 1st. Volume Flow Total… (Integer + Fraction) • 46183C00 is the 32-bit IEEE hexadecimal representation for 9743 (in base units of m3/hour) • 3F190AB1 is the 32-bit IEEE hexadecimal representation for 0.59781936 (in base units of m3/hour)

2nd. Volume Flow Total… (Integer + Fraction) • 4615F400 is the 32-bit IEEE hexadecimal representation for 9597 (in base units of m3/hour) • 3EE34094 is the 32-bit IEEE hexadecimal representation for 0.44385207 (in base units of m3/hour)

Note: Fractional values of a rollover total are always accurate to 8 decimal places irrespective of the selected display format for volume categorised data.

Action 3 of 3: Read 1 register starting from MODBUS register 2001 (Values Section, ‘Block C’)

Transmit 03 03 07 D1 00 01 D4 A5


Receive 03 83 02 61 31

Meaning Slv. Fn. D.C. Chk sum

Result: Response indicates that there are no parameters listed in ‘Block C’



HIGH-SPEED LIST COMMUNICATIONS GUIDED EXAMPLE (1b) Objective: Write new fixed values to the two known parameters listed under ‘Block A’ of High-speed List One

Block A Entry 1

Decimal Value (Before Update)

Decimal Value (After Update)

Block A Entry 2

Decimal Value (Before Update)

Decimal Value (After Update)

IV rate 0 3664 GV rate 0 3712

Abbreviations: “IV” = Indicated Volume, “GV” = Gross Volume

Action 1 of 1: Write values to two registers starting from MODBUS register 1 (Values Section, ‘Block A’)

• 45650000 is the 32-bit IEEE hexadecimal representation for 3664 • 45680000 is the 32-bit IEEE hexadecimal representation for 3712

Transmit 03 10 00 01 00 02 08 45 65 00 00 45 68 00

Meaning Slv. Fn. Reg. ID Reg. Cnt. DC The Data … The Data … The

Transmit 00 4C 7E

Meaning Data Chk Sum

Receive 03 10 00 01 00 02 11 EA


Result: • Indicated Volume and Gross Volume rates are updated with new fixed values. Notes: • The new parameter values are expected by the slave device to be in base measurement units of m3/hour.

To find out the base units for other parameter categories, turn to Chapter 9.

(2a) Objective: Read the location IDs of the first three ‘entry’ configuration parameters of Block B

Block A Entry 1 Loc. ID Block A Entry 2 Loc. ID Block A Entry 3 Loc. ID DBM list 1B ptr 1 2459 DBM list 1B ptr 2 2460 DBM list 1B ptr 3 2461

Action 1 of 1: Read three registers starting from MODBUS register 11001 (Loc. IDs Section, ‘Block B’)

Transmit 03 03 2A F9 00 03 DC 00


Receive 03 03 06 09 9B 09 9C 09 9D 59 1B

Meaning Slv. Fn. D.C. The data … The Data … Chk sum

Result: • 099B is the 16-bit hexadecimal representation for 2459 – the database location ID of <”DBM list 1B ptr 1”> • 099C is the 16-bit hexadecimal representation for 2460 – the database location ID of <”DBM list 1B ptr 2”> • 099D is the 16-bit hexadecimal representation for 2460 – the database location ID of <”DBM list 1B ptr 3”>

Note:

2AF9 (Reg. ID) is the hexadecimal representation for 11001



GUIDED EXAMPLE HIGH-SPEED LIST COMMUNICATIONS (2b) Objective: Add an entry to ‘High-speed List 1’ via the parameter list of Block C

Action 1 of 1: Write the database location ID of <”Gross std vol rate”> into the database location of <”DBM list1C ptr 1”> (ID: 2509)

• 09CC is the 16-bit hexadecimal representation for 2508 – the MODBUS address for <”DBM list1C ptr 1”> • 029D is the 16-bit hexadecimal representation for 0669 – the database location ID of <”Gross std vol rate”>

Transmit 01 10 09 CC 00 01 02 02 9D EE 55

Meaning Slv. Fn. Reg. ID Reg. Cnt. DC The Data Chk Sum

Receive 01 10 09 CC 00 01 C2 6A

Meaning Slv. Fn. Reg. ID Reg. Cnt. Chk Sum Note: • At present, the remote manipulation of a parameter list is achieved through the register map for the 7955

database (at the base slave address). See Chapter 7 for further examples of accessing the database.

(3a) Objective: Read data type and size of a value from all parameters listed in ‘Block A’ of High-speed List One

Action 1 of 1: Read two registers starting from MODBUS register 20001 (Types Section, ‘Block A’)

Transmit 03 03 4E 21 00 02 82 CB


Receive 03 03 04 07 04 07 04 9A B5

Meaning Slv. Fn. D.C. The Data … … Chk Sum

Result: • 0704: “07” = 32-bit floating-point data type, “04” = 4 bytes for representing the value

Note: • See Table 12 on page 7b.17 when interpreting other codes for the data type and size

(4a) Objective: Read value status from each parameter listed in ‘Block A’ of High-speed List One

Action 1 of 1: Read two registers starting from MODBUS register 30001 (Status Section, ‘Block A’)

Transmit 03 03 75 31 00 02 8E 2A


Receive 03 03 04 00 01 00 00 88 33

Meaning Slv. Fn. D.C. The Data … … Chk Sum

Result: There are four bytes of parameter data returned: 0x0001 and 0x0002

• 0x0001 = “Set” value status • 0x0000 = “Live” value status Note: For the interpretation of other codes, refer to Table 11 on page 7b.17.



HIGH-SPEED LIST COMMUNICATIONS GUIDED EXAMPLE

Table 11: Codes for all returned states

Value * State Return

0x0000 • Live

0x0001 • Set

0x0002 • Fail

0x0003 • Fallback

0x00FF • No state

* All values in this table are hexadecimal numbers

Table 12: Interpreting Data from Type and Size Requests

Database Location Type Size (Bytes) * Type (Code)

• Character 2 1

• Unsigned 8-bit integer 2 2


• Signed 16-bit integer 2 4


• Signed 32-bit integer 4 6

• 32-bit floating-point number 4 7

• 64-bit floating-point number 8 8

• Character String 22 9

• Multiple-choice (List) Option 2 10

• Location pointer 2 11

• Time and date 16 12

* All values in this column are decimal numbers



WONDERWARE COMPATIBILITY NOTES

7b.3 Using Wonderware’s Modbus I/O Server with High-Speed Lists Background The MODBUS specification glances over the concept of different address ranges containing different data types (and only those types in that range), and therefore using different MODBUS command numbers to manipulate the data. The specification goes on to say that ‘It is perfectly acceptable, and very common, to regard all four tables as overlaying one another, if this is the most natural interpretation on the target machine in question’. While individual manufacturers have mostly banded their data somewhat, but in smaller bands that do not fit this ‘four-table’ approach, Wonderware’s software has stuck to the separate address range method rigidly. For some individual manufacturers it has knowledge of, it has allowed them to specify their own arrangements, and will honour them; without that, you must use absolute addressing, which relies on the different command numbers for different ranges. Because 7955 Flow Computers only support commands 3 and 16 covering the whole range of 0 – 65535, absolute addressing cannot be used; up until now, none of the other manufacturers’ implementations could be used either.

Now With the flexibility of the new high-speed lists, it is now possible to get most important data by simulating one of the other manufacturers. In the future, Wonderware will support the 7955 directly. For now, here is how you can read floating-point data types and long integers (totals in their most accurate representation) using Wonderware:

1. Configure the communications parameters on the 7955

<Configure>/<Other parameters>/<Communications><Ports>

<Port X>/<Modbus parameters>/<Slave features> “Alarm+L1+L2+Dlog” (recommended) <Port X>/<Modbus parameters>/<Long reg access> “Single register” <Port X>/<Modbus parameters>/<Real precision> “Single precision”

<Configure>/<Other parameters>/<Communications>/<Modbus slave>

<High-speed list 1>/<Word order> “Modbus default” <High-speed list 1>/<Layout> “Grouped” (recommended) <High-speed list 1>/<Grouped start address> 7001 (required for compatibility reasons) <High-speed list 2>/<Word order> “Modbus default” <High-speed list 2>/<Layout> “Grouped” (recommended) <High-speed list 2>/<Grouped start address> 15001 (required for compatibility reasons)

With this arrangement floating-point values can be read from ‘high-speed list 1’ and long integers read from ‘high-speed list 2’. If you need to be able to read ‘floats’ and ‘longs’ from the same high-speed list, you will need to choose the “Ungrouped” style of register map and re-organise the start registers for each block section as appropriate. You will not be able to read ‘floats’ and ‘longs’ from within the same block, as they require different address ranges.

2. Configure Wonderware’s Modbus I/O server:

(2a) Configure the “Topic Definition” - choose a name such as “25x0L1” (2b) Select the MODBUS slave address - the base address + 2 (for high-speed list 1)

(2c) Select “Omni” as the ‘Slave device type” – Omni’s arrangement is the only one currently which can

be used with the 7955. (2d) Repeat for 2a – 2c for ‘High-speed List 2’ (if applicable)

You should now be able to use the I/O server via, for example, In Touch.

16-BIT COMMUNICATIONS

(GOULD LIST)

(CHAPTER 7 ADDENDUM C)

Chapter 7C: 16-bit Communications (Gould List) Software Version 2540, Issue 4.30.00 (or higher)

Page 7C.2 7955 2540 (Ch07C/AB)

7C 16-bit Communications (Gould List)

7C.1 Overview Chapter 7C is a guide to the software support for 16-bit only MODBUS protocol communications, which utilises the Gould List in this 7955 menu:

<”Configure”>/<”Other parameters”>/<Communications>/<”MODBus slave”>/<”Gould list”>. This feature is required when a MODBUS Master 1 is to exchange 16-bit 2 data with one or more 7955 Flow Computers operating as a MODBUS Slaves, where all are attached to the same MODBUS network.

16-bits (Word) 1 Byte 1 Byte 8 bits 8 bits= =

Figure 7c.1: 16-bits

Note: For MODBUS network topologies and terminal connections, refer to main Chapter 7.

7C.1.1 Groundwork

On the 7955 Flow Computer, integer and floating-point values of parameters (locations) are represented by 16-bits, 32-bits or 64-bits, depending on the data type of the value – see Table 7c.1 and Figure 7c.2 (below). Note: Data representation theory is outside the scope of this guide – refer to a data communications book.

64-bits (4 Words) 16-bits (Word) 16-bits (Word) 16-bits (Word) 16-bits (Word)=

16-bits (Word) 16-bits (Word)32-bits (2 Words) =

Figure 7c.2: 32-bits and 64-bits

16-bit communications is unsuitable for accessing a value that is a character string (11x16-bits) or a value that is a time and date (8x16-bits) – they are therefore not included in Table 7c.1 or this guide.

Table 7c.1: 7955 Data types

Data Type Size • Unsigned 8-bit integer 16-bits

• Unsigned 16-bit integer 16-bits

• Signed 16-bit integer 16-bits

• Unsigned 32-bit integer 32-bits

• Signed 32-bit integer 32-bits

• 32-bit floating point number * 32-bits

• 64-bit floating point number * 64-bits

• Multiple-choice (List) Option 16-bits

• Location pointer 16-bits

* Floating-point number is either single-precision (32-bit) or double-precision (64-bit), depending on serial port option.

1 This MODBUS Master device cannot be a 7955 Flow Computer. Direct communication of a parameter value between 7955 Flow

Computers can be performed using the “Peer-To-Peer” communications feature. 2 16 binary bits e.g. 01010101 01010101

Software Version 2540, Issue 4.30.00 (or higher) Chapter 7C: 16-bit Communications (Gould List)

7955 2540 (Ch07C/AB) Page 7C.3

7C.1.2 7955 16-bit communication features

7955 16-bit communications allows a MODBUS Master to:

• Read a 16-bit value – the full value – from a 16-bit parameter (location) – Multiple Register Access.

• Read a 16-bit value from any 16-bit segment of a 32-bit or 64-bit parameter (location) – Mult. Reg. Access.

• Read a full value from a 32-bit of 64-bit parameter (location) – Single Register Access.

• Write 3 a 16-bit value – the full value – to a 16-bit parameter (location) – Multiple Register Access.

• Write a 16-bit value to any 16-bit segment of a 32-bit or 64-bit parameter (location) – Mult. Reg. Access.

• Write a full value to a 32-bit or 64-bit parameter (location) – Single Register Access.

The ‘16-bit value’ may be scaled (x10, x100 or x1000) before transmission to the MODBUS Master and de-scaled (÷10, ÷100 or ÷1000) before being saved to an application parameter (location). This optional feature is explained in Section 7C.1.9.

In addition, serial port parameters for selecting Single or Multiple (Long) Register Access, MODBUS Word Order, Single or Double Precision and Totals format affect 16-bit communications – see Section 7C.1.13 for details of their effect.

7C.1.3 16-bit segments (Gould Registers) when using Multiple Register Access

Figure 7c.3 shows how a 16-bit, 32-bit and 64-bit parameter value is viewed as one or more 16-bit segments. When using Multiple Register Access, each segment is a Gould Register that can be individually read or written if set-up in a Gould List.

16-bits (1 Word) 16-bits (1 Word)

16-bits (1 Word) 16-bits (1 Word) 16-bits (1 Word) 16-bits (1 Word)

Gould Register Gould Register

Gould Register Gould Register Gould Register Gould Register

16-bits (1 Word)

Gould Register

16-bit Parameter(Database Location)



Note: A floating-point number is either single-precision (32-bit) or double-precision (64-bit), depending on the

Real Precision option selected for the serial port.

Figure 7c.3: 16-bit segments (Gould Registers) when using Multiple Register Access

It follows then that the Gould Register access for a 32-bit (or 64-bit) parameter is slightly different to accessing a 16-bit parameter.

In Figure 7c.4, a 16-bit value is written, as a full value, to the only 16-bit segment (Gould Register) of a 16-bit parameter. Similarly, a whole value can be read from the same Gould Register.

3 The 7955 will prevent writing to parameters (locations) dedicated to incremental totals, such as the Corrected Volume flow total.


Page 7C.4 7955 2540 (Ch07C/AB)

16-bit value

7955 Flow Computer (MODBUS Slave)MODBUS Master

16-bits (1 Word)

Gould Register


Application

Figure 7c.4: Accessing the full value of a 16-bit parameter in one step In Figure 7c.5, a 16-bit value is read from the first 16-bit segment (Gould Register) of a 32-bit parameter. A further message (request) is required to read to the second 16-bit segment (Gould Register). With values from both segments retrieved, the full value can be assembled by the MODBUS Master. The same principle applies to 64-bit parameters, except there are four of the 16-bit segments. Note: More than one Gould Register can be accessed at the same time if the 7955 Gould List is set-up appropriately.

16-bit value


16-bits (1 Word)

Gould Register


Application

16-bits (1 Word)

Gould Register

16-bit value


16-bits (1 Word)

Gould Register


Application

16-bits (1 Word)

Gould Register

(Read first 16-bit segment)

(Read final 16-bit segment)

Figure 7c.5: Accessing a full value of a 32-bit parameter in two steps

7C.1.4 16-bit segments (Gould Registers) when using Single Register Access

Figure 7c.6 shows how a 16-bit, 32-bit and 64-bit parameter value is viewed as one or more 16-bit segments. When using Single Register Access, all 16-bit segments – the full value – equate to one Gould Register that can be individually read or written if set-up in a Gould List. Therefore, reading a Gould Register will retrieve the full value, irrespective of the parameter data type. Similarly, a full value can be written to the Gould Register. Note: More than one Gould Register can be accessed at the same time if the 7955 Gould List is set-up appropriately.


7955 2540 (Ch07C/AB) Page 7C.5

16-bits (1 Word) 16-bits (1 Word)

16-bits (1 Word) 16-bits (1 Word) 16-bits (1 Word) 16-bits (1 Word)

Gould Register

Gould Register

16-bits (1 Word)

Gould Register




Note: A floating-point number is either single-precision (32-bit) or double-precision (64-bit), depending on the

Real Precision option selected for the serial port.

Figure 7c.6: 16-bit segments (Gould Registers) when using Single Register Access


Page 7C.6 7955 2540 (Ch07C/AB)

7C.1.5 Gould List

On the 7955 Flow Computer, the Gould List comprises menu entries for nominating up to 50 Gould Registers. Each list entry requires user-entered details, which include:

• a user-nominated address for the Gould Register (e.g. 40001)

• the unique 4-digit location identification number of the associated parameter (e.g. Loc ID: 0144)

• Word Offset – 0, 1, 2 or 3 – for selecting a 16-bit segment of the parameter value (if applicable)

• Scaling factor – x10, x100, x1000 or none – for scaling/de-scaling the 16-bit data being exchanged

The 7955 Gould List can be set-up for Multiple Register Access or Single Register (or a mixture if using more than one serial port.)

Figure 7c.7 shows an example 7955 Gould List set-up for Multiple Register Access. There are 3 entries populated with user-entered details.

Gould List entries 1 and 2 are set-up for accessing the first 16-bit segment (Gould Register 40001) and final 16-bit segment (Gould Register 40002) of a 32-bit parameter (location), perhaps a flow rate.

Since the full value of parameter 0144 is represented in 32-bits, the Word Offset option must be used to select which 16-bit segment is associated with the nominated Gould Register address.

Word Offset 0 selects first 16-bit segment. Word Offset 1 selects the final 16-bit segment. (Word Offset 2 and 3 are applicable only for a 64-bit parameter.)

Gould List entry 3 is set-up for accessing a 16-bit parameter, but there is a deliberate mistake. The Word Offset is 1, which is incorrect since there is no second 16-bit segment in a 16-bit parameter. Likewise, Word Offsets 2 and 3 would also be incorrect as there are no third and fourth segments. To correct the error, Word Offset 0 must be selected.

Gould List entry 50 is not in use and shows the factory default settings. Note: A location ID of 0 (“Off”) will terminate the 7955 Gould List – do not skip entries in the 7955 Gould List.

Location ID: 0144

459.21Value

Data Size 32-bit

GO

ULD

LIS

T

7955 Flow Computer(MODBUS Slave)

DA

TA

BA

SE

1

2

3

50

GOULD LIST DATABASE

Location ID:

Scaling:

Gould Reg: 40001

0144

Word Offset: 0

No scaling

Location ID:

Scaling:

Gould Reg: 40002

0144

Word Offset: 1

No scaling

Location ID:

Scaling:

Gould Reg: 50001

1429

Word Offset: 1

No scaling Location ID: 1429

0Value

Data Size 16-bit

Location ID:

Scaling:

Gould Reg: 0

Off

Word Offset: 0

No scaling

Note: A floating-point number (e.g. 459.21) is either single-precision (32-bit) or double-precision (64-bit),

depending on the Real Precision option selected for the serial port.

Figure 7c.7: 7955 Gould List (Multiple Register Access)


7955 2540 (Ch07C/AB) Page 7C.7

Figure 7c.8 shows an example 7955 Gould List set-up for Single Register Access. Again, there are 3 entries populated with user-entered details.

Gould List entry 1 is set-up for accessing the full value – all 16-bit segments – of Gould Register 40001. Since the full value of parameter 0144 is read in one go, the Word Offset option is not used and it is kept set to the factory default of Word Offset 0. Gould List entry 2 is set-up for accessing the full value – all 16-bit segments – of Gould Register 40002. Again, since the full value of parameter 0167 is read in one go, the Word Offset option is not used and it is kept set to the factory default of Word Offset 0. Since Gould Register 40001 and 40002 have addresses in sequence and are in consecutive entries, they can both be read at the same time. Gould List entry 3 is set-up for accessing the full value – a single 16-bit segment – of Gould Register 50001. Again, the Word Offset option is not used and it is kept set to the factory default of Word Offset 0. Gould Register 40002 and 50001 are in consecutive entries but the addresses are not in sequence; they cannot both be read at the same time. Gould List entry 50 is not in use and shows the factory defaults. Note: A location ID of 0 (“Off”) will terminate the 7955 Gould List – do not skip entries in the 7955 Gould List.

Location ID: 0144

459.21Value

Data Size 32-bit

GO

ULD

LIS

T

7955 Flow Computer(MODBUS Slave)

DA

TA

BA

SE

1

2

3

50

GOULD LIST DATABASE

Location ID:

Scaling:

Gould Reg: 40001

0144

Word Offset: 0

No scaling

Location ID:

Scaling:

Gould Reg: 40002

0167

Word Offset: 0

No scaling

Location ID:

Scaling:

Gould Reg: 50001

1429

Word Offset: 0

No scaling

Location ID: 1429

0Value

Data Size 16-bitLocation ID:

Scaling:

Gould Reg: 0

Off

Word Offset: 0

No scaling

Location ID: 0167

2359.54Value

Data Size 32-bit

Note: A floating-point number (e.g. 459.21) is either single-precision (32-bit) or double-precision (64-bit),

depending on the Real Precision option selected for the serial port.

Figure 7c.8: 7955 Gould List (Single Register Access)


Page 7C.8 7955 2540 (Ch07C/AB)

7C.1.6 Gould List: Gould Register Addressing

The address of a Gould Register can be edited to be any number in the range 0 to 65535 (0x0000 to 0xFFFF), as long as it is unique in the Gould List.

Attempts to enter an address outside this range will be responded to with an “** ERROR **” message, on-screen for a few seconds, and the original setting is then restored.

When accessing more than one Gould Register at a time, the user-entered addresses must be in sequence (e.g. 1300, 1301, etc) and in consecutive entries in the Gould List.

When accessing one Gould Register at a time, the addresses of consecutive entries in the Gould List do not have to be in sequence (e.g. 1300, 1400, etc.)

7C.1.7 Gould List: Parameters (Locations)

To find the unique identification number of a parameter (location), navigate to the parameter screen and press the a-button to display the number.

7C.1.8 Gould List: Word Offset

Word Offset settings in the Gould List are only applicable when using Multiple Register Access (rather than using Single Register Access).

With Multiple Register Access, each Gould Register equates to a 16-bit segment of data. Therefore, you select the segment that will equate to the register. Word Offset 0 The Gould Register is mapped to the only 16-bit segment of a 16-bit parameter value or it is mapped to the first 16-bit segment of a 32-bit or 64-bit parameter value. Word Offset 1 The Gould Register is mapped to the second 16-bit segment of a 32-bit or 64-bit parameter value. Word Offset 2 The Gould Register is mapped to the third 16-bit segment of a 64-bit parameter value. Word Offset 3 The Gould Register is mapped to the fourth 16-bit segment of a 64-bit parameter value.

Examples can be found in Section 7C.3.

Note: With Single Register Access, each Gould Register equates to the whole value (all 16-bit segments).

7C.1.9 Gould List: Scaling Factor

The scaling factor, 10, 100 or 1000, is effective only when accessing floating-point values.

If selected for a Gould Register, the factor is applied, therefore converting it into a whole number (integer) before or transmitted or vice versa if being saved.

If no scaling factor is to be applied, select “No Scaling” – this is the factory default for each Gould List entry.

The purpose of this feature is for systems that cannot handle float conversions – they may ask for temperature x 100 (as an integer). You cannot get scaled values as a floating-point value.

Practical examples can be found in Section 7C.3.


7955 2540 (Ch07C/AB) Page 7C.9

7C.1.10 MODBUS Message Exchanges

The MODBUS Master can access more than one Gould Registers in one request. To access the registers, it must transmit a read or write MODBUS protocol message addressed to the 7955 MODBUS slave. The slave will then reply with a MODBUS protocol message. Note: Write messages can be broadcast to all 7955 MODBUS slaves with a MODBUS slave address of 0. Gould registers can be accessed through any serial port configured to be a MODBUS slave and the Gould List access is enabled by the port MODBUS feature parameter. (Full configuration details are in Section 7C.2.)

7C.1.11 Read Message Format (Single or Multiple Gould Register Access)

Figure 7c.9 shows the MODBUS function 03 command format. Practical examples, showing other Read messages and responses, can found in Section 7C.3.

Slave Address

Function G. Reg. (H.O.)

G. Reg. (L.O.)

# Of Reg. (H.O.)

# Of Reg. (L.O.)

EC LRC

06 03 9C 41 00 02 X X

Figure 7c.9: MODBUS message for reading from Gould Registers 40001 and 40002

Slave Address – On the 7955, this is a Virtual Slave address: Base Slave Address +5 (= 06 if factory default)

Function – 03 (0x03) is the function code for MODBUS read messages.

G. Reg. – Address of Gould Register, e.g. 40001 (Decimal) or 0x9C41 (Hexadecimal)

# of Reg. – Specify number of Gould Registers to be read, e.g. 0002 (Decimal and Hexadecimal)

EC – Error check number, generated is accordance with the MODBUS specification

LRC – Longitudinal redundancy check number, generated in accordance with the MODBUS specification

7C.1.12 Write Message Format (Single or Multiple Gould Register Access)

Figure 7c.10 shows the MODBUS function 16 command format. Practical examples, showing other Write messages and responses, can found in Section 7C.3.

Slave Add.

Funct. G. Reg. (H.O.)

G. Reg. (L.O.)

Quantity Byte Count

16-bit data 16-bit data EC LRC

06 10 9C 41 00 02 04 (H.O.) (L.O.) (H.O.) (L.O.) X X

Figure 7c.10: MODBUS message for writing to Gould Registers 40001 and 40002

Slave Address – On the 7955, this is a Virtual Slave address: Base Slave Address +5 (= 06 if factory default)

Function – 16 (0x10) is the function code for MODBUS write messages.

Gould Register – Address of Gould Register, e.g. 40001 (Decimal) or 0x9C41 (Hexadecimal)

Quantity – Specify number of Gould Registers to be write to, e.g. 2 for 40001 (0x9C41) and 40002 (0x9C42)

Byte Count – Specify number of bytes of data e.g. 0x02 for a 16-bit value, 0x04 for two 16-bit values, etc.

16-bit data – Up to fifty 16-bit IEEE values, dependent on Quantity field

EC – Error check number, generated is accordance with the MODBUS specification

LRC – Longitudinal redundancy check number, generated in accordance with the MODBUS specification


Page 7C.10 7955 2540 (Ch07C/AB)

7C.1.13 Serial port parameters (locations)

Each serial port has parameters for selecting Single or Multiple (Long) Register Access, MODBUS Word Order, Single or Double Precision and Totals format affect 16-bit communications. <Long Register Access> The 7955 Flow Computer has support for both Single Register Access and Multiple Register Access. Each serial port is configured to allow one type of register access. Multiple Register Access: With this type of access, each Gould Register equates to a single 16-bit segment. Therefore, to read a 32-bit value, two Gould Registers are required. Similarly, to read a 64-bit value, four Gould Registers are required. Single Register Access: With this type of access, each Gould Register equates to all the 16-bit segments required for a full value. Therefore, to read a 16-bit value, 32-bit value or 64-bit value, only one Gould Register is required. <MODBUS Word Order> The 7955 Flow Computer provides the facility to choose the Word (double-byte) ordering of data fields in MODBUS messages. This feature is individually selectable for each serial port. Figure 7c.11 shows the effect of the Default Order option and Word Swap option for single-precision (32-bit) and double-precision (64-bit) values. For 64-bit values, the second double Word is the most significant.

WORD '1'(16 Bits)


Word Swap

42 C2 3F 0D

WORD '1'(16 Bits)

WORD '2'(16 Bits)

42 C23F 0D

SINGLE PRECISION

WORD '1'(16 Bits)


Word Swap

40 58 47 E1

WORD '3'(16 Bits)

WORD '4'(16 Bits)

9B 90EA 9E

DOUBLE PRECISION

WORD '3'(16 Bits)

WORD '4'(16 Bits)

9B 90 EA 9E

WORD '2'(16 Bits)

WORD '1'(16 Bits)

47 E1 40 58

Figure 7c.11: Word Ordering Examples

<Real Precision>

Floating-point values (e.g. flow rates) are made available as a 32-bit IEEE (single-precision) number or as a 64-bit IEEE (double-precision) number. The precision level is individually selectable for each serial port. <Total Format> Each incremental total can be read as two separate 32-bit integers or as a single floating-point value, depending on the option selected. The format is individually selectable for each serial port. When a flow total value (e.g. 2983.54) is to be read as a 32-bit integer, there is one parameter (location) with the “2953” and another parameter (location) with the “54”. When a flow total value (e.g. 2983.54) is to be read as a floating-point value, there is just one parameter (location) with the “2953.54”.


7955 2540 (Ch07C/AB) Page 7C.11

7C.2 Configuring and Activation Instructions Follow these instructions to configure and activate 16-bit communications on the 7955 Flow Computer:

1. Ensure that 7955 Flow Computers and MODBUS Maste device are already interconnected to form a

MODBUS network. (Guidance on the necessary RS-232 or RS-485 wiring 4 is in the main Chapter 7.)

2. Program a 7955 Flow Computer to be the MODBUS slave device


(2b) Select a Serial Port menu, as appropriate for the serial port connected to the MODBUS network.

(2c) Configure the basic communication parameters for that serial port, as shown in Table 7c.2. (Some localised menu navigation is required to find the parameter screen.)

3. Configure entries in the Gould List

(3a) Navigate to this menu: <”Configure”>/<”Other Parameters”>/<”Communications”>/<”MODBus slave”>

(3b) Select this menu: <“Gould list”>

(3c) Configure each list entry, as guided in Table 7c.3. Start with configuring Entry 1, then configure Entry 2, and so forth. Avoid skipping an entry, since the list is terminated by a location ID of 0.


The MODBUS Master can read and write to the Gould Registers.

4 To avoid the risk of flow computer restarts, it is advisable to pre-set the signalling standard – RS-232 or RS-485 – for 7955 serial

ports before establishing the physical connections.


Page 7C.12 7955 2540 (Ch07C/AB)

Table 7c.2: Basic Serial Port Communication Parameters

Parameter * (Database Location) Instructions and Comments Factory Default

Setting

Comms port owner Select the multiple-choice option with “Modbus slave”. “MODBUS slave”

Port Baud rate Select a rate that will be the same for the MODBUS Master device and all 7955 MODBUS slave devices.

“19200”

Port char format Select a character transmission format (as agreed for the MODBUS network). If unsure, keep the factory default.

“8 bits none 1 stop”

Port handshaking Select either “None” or “XonXoff” unless the cable supports “CTS/RTS”. (If unsure, keep the factory default.)

“None”

Port RS232 / 485 *** Select signalling standard for the MODBUS network ** “RS 232”

Port Modbus mode Select the option that is compatible with the other MODBUS network devices. (If unsure, keep the factory default.)

“RTU”

P Modbus word order Select an option that is compatible with the Master device. (If unsure, keep the factory default.) “Modbus default”

P MODB slave add Edit the Base Slave Address of this slave. 1

P Modbus features Select the multiple-choice option that includes “Gou“ (Gould) “None”

P long reg access Choose single or multiple Gould Register access. “Multiple registers”

P MODB total format Select how total values are to be transmitted – either 32-bit integers or as a single/double-precision floating-point value.

“32-bit integer”

P MODB precision Select the accuracy of all floating-point values for this serial port: single-precision (32-bits) or double-precision (64-bits). “Single”

* The on-screen parameter descriptor includes a digit to identify the associated serial port. ** A 7955 may perform ‘warm restarts’ if it is configured to be “RS 232” when it should be “RS 485”.

*** Parameter is not applicable to Serial Port One since it is for RS-232 devices only. Abbreviations used: “P” = Port, “reg” = register, “addr” = address, “char” = character, “MODB” = MODBUS

Table 7c.3: Gould List Entry Parameters (Locations)


Setting

List1 Gould reg Enter a numeric address for the Gould Register e.g. 40001. 0

List1 mapped loc ** Enter the unique identification number (Loc ID) of the parameter (location) to be mapped to the Gould Register.

Off

List1 Word Offset If using multiple register access and mapped parameter has a 32-bit/64-bit value, select the 16-bit segment of the value to be accessed.

“Word Offset 0”

List1 scale factor If the 16-bit data is a floating-point number, it can be scaled into an integer (x10, x100 or x1000) just before transmission to the MODBUS Master. Similarly, it can be de-scaled before saving it.

“No scaling”

* The on-screen parameter descriptor includes a number to identify the list entry.

** Entering a valid location number will immediately result in the number changing to the parameter descriptor. Editing a location number for a parameter that does not exist is responded to with a “** ERROR **” message appearing briefly, and the original setting is then restored.

Abbreviation used: “reg” = register, “loc” = location


7955 2540 (Ch07C/AB) Page 7C.13

7C.3 Guided Examples This section is a practical guide to accessing Gould Registers of a 7955 MODBUS Slave through the Gould List feature. What to do here:

1. Ensure that the 7955 Flow Computer is suitably configured as guided in Section 7C.2. 2. Follow examples from Table 7c.4 or Table 7c.5.

In the examples, MODBUS message sequences aim to show the how to read from Gould Registers and write to Gould Registers. Every example features an objective, an action and a result Objective(s) For an example, the objective could be to read a 16-bit parameter value. Action(s) Actions consist of one or more MODBUS protocol commands. They are represented in this documentation as tabulated hexadecimal values in sequence for transmission by the Master device. Expected responses from the 7955 MODBUS slave device are also shown as tabulated values. Table 7c.6 is a list of all the abbreviations of meanings that can appear with a sequence. Use them to distinguish the important elements of the message.

Result This is a brief analysis of the MODBUS slave response to an action. Note: Values are communicated in base units, which may not be the same as the displayed units – see Table 7c.7.

3. Experiment

Try out the examples and then adapt them to suit your requirements.

Table 7c.4 : Summary of examples (reading from Gould Registers)

Example Number

Totals format

Precision Word Order

Register Access

Scaling Access

Beyond Value Consecutive

Registers Page

1 X Single Default Multiple None No Yes 15

2 X Single Default Multiple None No No 16

3 X Single Default Multiple None Yes Yes 17

4 X Single Default Multiple x100 No Yes 18

5 X Single Default Single None No Yes 19

6 X Double Default Multiple None No Yes 20

7 X Double Default Single None No Yes 21

8 Integer Single Default Single None No Yes 22

9 Integer Single Default Multiple None No Yes 23

10 Fl. point Double Default Single None No Yes 24


Page 7C.14 7955 2540 (Ch07C/AB)

Table 7c.5: Summary of examples (writing to Grould Registers)

Example Number

Totals format Precision Word

Order Register Access Scaling Access


Registers Page



3 X Single Default Single None No Yes 27

4 X Single Default Multiple x100 No Yes 28

5 X Single Default Single x100 No Yes 29

Table 7c.6: Abbreviations for Interpreting Elements of Transmit and Response Sequences

Abbreviation Meaning Slv. Base Slave Address +5. It is 0x06 for the examples.


Fn. Function code. E.g. 03 = Read Gould Register(s)

Reg. Cnt Quantity of Gould Registers

Reg. ID Gould Register number

D.C. Number of ‘data bytes’ in reply

Data Data byte

EC & LRC Calculated checksum, which is two bytes at the end

Table 7c.7: Base units of measurement

Category Base units Temperature Deg. C

Pressure bar abs

Differential pressure mbar

Density kg/m3

Frequency μs

Fraction %

Time seconds

Flow factor pulse/m3

Volume total m3

Base volume total std m3

Mass Total kg

Energy Total MJ

Mass rate g/min

Volume rate m3/hour

Energy rate MJ/hour

Energy value (mass) MJ/kg

Energy value (volume) MJ/m3

Base volume rate Std m3/hour

Length m

Dynamic viscosity cP

Absolute zero Deg.C

Velocity m/s

Orifice Coeffient PPM/Deg.C


7955 2540 (Ch07C/AB) Page 7C.15

7C.3.1 Gould List Read Access: Example 1

Objective: Read Meter-run Temperature parameter (database location ID: 0666) which has a 32-bit (single-precision) floating-point value.

Totals format


Register Access

Scaling Access


Registers X Single Default Multiple None No Yes

This example involves reading two Gould Registers 1300 and 1301; this is to get the two lots of 16-bit data. Importantly, they are given consecutive entries in the Gould List. Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, multiple register access, single-precision. Gould List Configuration Gould List Entry 1: <List1 Gould reg 1> = 1300 <List1 mapped loc 1> = 0666 (Meter temperature) <List1 WordOffset 1> = “Word offset 0” <List1 scale fact 1> = “No scaling” Gould List Entry 2: <List1 Gould reg 2> = 1301 <List1 mapped loc 2> = 0666 (Meter temperature) <List1 WordOffset 2> = “Word offset 1” <List1 scale fact 2> = “No scaling” Action Read Gould Registers 1300 and 1301

Transmit 06 03 05 14 00 02 85 74

Meaning Slv. Fn. Reg. ID Reg. Cnt. EC LRC

Response 06 03 04 42 0C 00 00 58 88

Meaning Slv. Fn. D.C. Data Data Data Data EC LRC

Result • 420C0000 is the 32-bit IEEE hexadecimal representation for 35.0 (in base units of °C) • 420C is the 16-bit data from Gould Register 1300 and 0000 is the 16-bit data from Gould Register 1301


Page 7C.16 7955 2540 (Ch07C/AB)


Note: This is an error response example, which is a variation of Example 1. Objective: Read Meter-run Temperature parameter (database location ID: 0666) which has a 32-bit (single-precision) floating-point value.

Totals format


Register Access

Scaling Access


Registers X Single Default Multiple None No No

This is similar to example 1, except Gould Registers 1300 and 1301 are not given consecutive entries in the Gould List. Subsequently, there is an error response transmitted by the 7955 Flow Computer. Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, Multiple Register Access, Single-precision. Gould List Configuration Gould List Entry 1: <List1 Gould reg 1> = 1300 <List1 mapped loc 1> = 0666 (Meter temperature) <List1 WordOffset 1> = “Word offset 0” <List1 scale fact 1> = “No scaling” Gould List Entry 2: <List1 Gould reg 2> = 40001 <List1 mapped loc 2> = 0144 (Corrected volume flow rate) <List1 WordOffset 2> = “Word offset 0” <List1 scale fact 2> = “No scaling” Gould List Entry 3: <List1 Gould reg 3> = 1301 <List1 mapped loc 3> = 0666 (Meter temperature) <List1 WordOffset 3> = “Word offset 1” <List1 scale fact 3> = “No scaling” Action Read Gould Registers 1300 and 1301

Transmit 06 03 05 14 00 02 85 74


Response 06 83 02 71 30

Meaning Slv. Fn. D.C. Chk sum

Result • An error reponse (code 83) is given since Gould Registers 1300 and 1301 are not given consecutive

entries in the Gould List.


7955 2540 (Ch07C/AB) Page 7C.17


Note: This is an error response example, which is a variation of Example 1. Objective: Read Meter-run Temperature parameter (database location ID: 0666) which has a 32-bit (single-precision) floating-point value.

Totals format


Register Access

Scaling Access


Registers X Single Default Multiple None Yes Yes

This is similar to Example 1, except there is an attempt to read beyond Gould Register 1300 and 1301 by using the Word Offset 2 option and Word Offset 3 option. Subsequently, there is an error response transmitted by the 7955 Flow Computer, since the parameter does not have a 64-bit (double-precision) floating-point value. Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, multiple register access, single-precision. Gould List Configuration Gould List Entry 1: <List1 Gould reg 1> = 1300 <List1 mapped loc 1> = 0666 (Meter temperature) <List1 WordOffset 1> = “Word offset 2” <List1 scale fact 1> = “No scaling” Gould List Entry 2: <List1 Gould reg 2> = 1301 <List1 mapped loc 2> = 0666 (Meter temperature) <List1 WordOffset 2> = “Word offset 3” <List1 scale fact 2> = “No scaling” Action Read Gould Registers 1300 and 1301

Transmit 06 03 05 14 00 02 85 74


Response 06 83 02 71 30

Meaning Slv. Fn. D.C. EC LRC

Result • An error response (code 83) is given since parameter does not have a 64-bit (double-precision)

floating-point value.


Page 7C.18 7955 2540 (Ch07C/AB)


Objective: Read Meter-run Temperature parameter (database location ID: 0666) which has a 32-bit (single-precision) floating-point value.

Totals format


Register Access

Scaling Access


Registers X Single Default Multiple Yes No Yes

This example, which is a variation of Example 1, involves reading scaled (x100) values from two Gould Registers 1300 and 1301. Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, multiple register access, single-precision. Gould List Configuration Gould List Entry 1: <List1 Gould reg 1> = 1300 <List1 mapped loc 1> = 0666 (Meter temperature) <List1 WordOffset 1> = “Word offset 0” <List1 scale fact 1> = “Int (value x 100)” Gould List Entry 2: <List1 Gould reg 2> = 1301 <List1 mapped loc 2> = 0666 (Meter temperature) <List1 WordOffset 2> = “Word offset 1” <List1 scale fact 2> = “Int (value x 100)” Action Read Gould Registers 1300 and 1301

Transmit 06 03 05 14 00 02 85 74


Response 06 03 04 00 00 0D AC 88 1E

Meaning Slv. Fn. D.C. Data Data Data Data EC LRC

Result • 00000DAC is the 32-bit IEEE hexadecimal representation for 3500.0 (in base units of °C)


7955 2540 (Ch07C/AB) Page 7C.19


Objectives: • Read Meter-run Temperature (Loc. ID: 0666), a 32-bit (single-precision) floating-point value.

• Read Meter-run Temperature (Loc. ID: 0666) and Corrected Volume Rate (loc. ID: 0144), which both have 32-bit (single-precision) floating-point values.




Registers X Single Default Single None No Yes

Importantly, and unlike previous examples, single register access is used – only one Gould Register is required to get the full value (all 16-bit segments). Therefore, the Word Offset option has no effect.

This example involves: • Reading the whole temperature value from a single Gould Register – Action 1 • Reading whole values of temperature and flow rate from two consecutive Gould Registers – Action 2

Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, single register access, single-precision.

Gould List Configuration

Gould List Entry 1: <List1 Gould reg 1> = 1305 <List1 mapped loc 1> = 0666 (Meter temperature) <List1 scale fact 1> = “No scaling”


Action 1 Read whole temperature value from Gould Register 1305

Transmit 06 03 05 19 00 01 54 B6


Response 06 03 04 42 0C 00 00 58 88

Meaning Slv. Fn. DC Data Data Data Data EC LRC

Result • The data, 420C0000, is the 32-bit IEEE hexadecimal representation for 35.0 (in base units of °C) • 420C is the first 16-bit segment of data read from Gould Register 1305 (i.e. the integer part, 35) • 0000 is the final 16-bit segment of data read from Gould Register 1305 (i.e. the fractional part, .0)

Action 2 Read Gould Registers 1305 and 1306

Transmit 06 03 05 19 00 02 54 B6


Response 06 03 04 42 0C 00 00 42 20 00 00 D3 F8

Meaning Slv. Fn. DC Data Data Data Data Data Data Data Data EC LRC

Result • The data, 420C0000, is the IEEE hexadecimal representation for 35.0 (in base units of °C) • 420C is the first 16-bit segment of data read from Gould Register 1305 (i.e. the integer part. 35); the

0000 that follows final 16-bit segment of data read from Gould Register 1305 (i.e. the fractional part, .0) • The data, 42200000, is the IEEE hexadecimal representation for 40.0 (in base units of m3/hour) • 4220 is the first 16-bit segment of data read from Gould Register 1306; the 0000 is the other segment


Page 7C.20 7955 2540 (Ch07C/AB)


Objective: Read Meter-run Temperature parameter (Loc. ID: 0666) which has a 64-bit (double-precision) floating-point value.

Totals format


Register Access

Scaling Access


Registers X Double Default Multiple None No Yes

This example involves reading four Gould Registers 1300 - 1303; this is to get four lots of 16-bit data. Importantly, they are given consecutive entries in the Gould List.

Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, multiple register access and double-precision.


Gould List Entry 1: <List1 Gould reg 1> = 1300 <List1 mapped loc 1> = 0666 (Meter temperature) <List1 WordOffset 1> = “Word offset 0” <List1 scale fact 1> = “No scaling”




Action Read Gould Registers 1300 and 1301

Transmit 06 03 05 14 00 04


Response 06 03 08 40 41 80 00 00 00 00 00

Meaning Slv. Fn. D.C. Data Data Data Data Data Data Data Data EC LRC

Result • 404180000000 is the 64-bit IEEE hexadecimal representation for 35.0 (in base units of °C) • 4041 is the 16-bit data from Gould Register 1300, 8000 is the 16-bit data from Gould Register 1301, and

so forth.


7955 2540 (Ch07C/AB) Page 7C.21


Objectives: • Read Meter-run Temperature (Loc. ID: 0666), a 64-bit (double-precision) floating-point value.

• Read Meter-run Temperature (Loc. ID: 0666) and Corrected Volume Rate (loc. ID: 0144), which both have 64-bit (double-precision) floating-point values.




Registers X Double Default Single None No Yes

Importantly for this example, single register access is used – only one Gould Register is required to get a full value (i.e. all four 16-bit segments). Therefore, the Word Offset option has no effect.

This example involves: • Reading the whole temperature value from one Gould Register – Action 1 • Reading whole values of temperature and flow rate from two consecutive Gould Registers – Action 2

Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, single register access, double-precision.



Gould List Entry 2: <List1 Gould reg 2> = 1306 <List1 mapped loc 2> = 0144 (Corrected Volume flow rate) <List1 scale fact 2> = “No scaling”

Action 1: Read whole temperature value from Gould Register 1305

Transmit 06 03 05 19 00 01 54 B6


Response 06 03 08 40 41 80 00 00 00 00 00 C5 57


Result • 4041 8000 0000 0000 is the 64-bit IEEE hexadecimal representation for 35.0 (in base units of °C) • The first 8 bytes of data, 4041 8000, is the first and second 16-bit data segments (of the 64-bit value)

read from Gould Register 1305 (i.e. the integer part, 35) • The last 8 bytes of data, 0000 0000, is the third and fourth 16-bit data segments (of the 64-bit value)

read from Gould Register 1305 (i.e. the fractional part, .0)

Action 2: Read Gould Registers 1305 and 1306

Transmit 06 03 05 19 00 02 14 B7


Response 06 03 10 40 41 80 00 00 00 00 00 40 44

Meaning Slv. Fn. DC Data Data Data Data Data Data Data Data Data Data

Response 00 00 00 00 00 00 60 99

Meaning Data Data Data Data Data Data EC LRC

Result • 4041 8000 0000 0000, is the 64-bit IEEE hexadecimal representation for 35.0 (in base units of °C) • 4042 0000 0000 0000, is the 64-bit IEEE hexadecimal representation for 40.0 (in base units of m3/hour)


Page 7C.22 7955 2540 (Ch07C/AB)


Objectives: • Read Indicated Volume total in 32-bit integer format.

Totals format


Register Access

Scaling Access


Registers Integer X Default Multiple None No Yes

Importantly for this example, Multiple Register Access is used – more than one Gould Register is required to get a full 32-bit value (i.e. all 16-bit data segments). Therefore, the Word Offset option is required.

This example involves reading two whole integer values, requiring four Gould Registers.

Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1 and Multiple Register Access.


Gould List Entry 1: <List1 Gould reg 1> = 1400 <List1 mapped loc 1> = 0174 (Indicated Volume total, whole part) * <List1 WordOffset 1> = “Word Offset 0” <List1 scale fact 1> = “No scaling”

Gould List Entry 2: <List1 Gould reg 2> = 1401 <List1 mapped loc 2> = 0174 (Indicated Volume total, whole part) * <List1 WordOffset 2> = “Word Offset 1” <List1 scale fact 2> = “No scaling”

Gould List Entry 3: <List1 Gould reg 3> = 1402 <List1 mapped loc 3> = 0172 (Indicated Volume total, fractional part) * <List1 WordOffset 3> = “Word Offset 0” <List1 scale fact 3> = “No scaling”

Gould List Entry 4: <List1 Gould reg 4> = 1403 <List1 mapped loc 4> = 0172 (Indicated Volume total, fractional part) * <List1 WordOffset 4> = “Word Offset 1” <List1 scale fact 4> = “No scaling”

* Parameter is not visible within the menu system. For a full location listing, contact factory.

Action 1: Read Gould Registers 1400 - 1403

Transmit 06 03 05 78 00 04 C5 6B


Response 06 03 10 45 09 A0 00 3F 7D 0B 5C 51 09


Result • 4509 A000 is the 32-bit IEEE hexadecimal representation for 2202.0 (in base units of m3) • The first 8 bytes of data, 4509 A000, is the first and second 16-bit data segments (of the 32-bit value)

read from Gould Register 1400 (i.e. the integer part, 2202.0) • 3F7D 0B5C is the 32-bit IEEE hexadecimal representation for 0.98845457 (in base units of m3) • The last 8 bytes of data, 3F7D 0B5C, is the first and second 16-bit data segments (of the 32-bit value)

read from Gould Register 1401 (i.e. the fractional part, 0.98845457)

Note: Fractional values of a rollover total are always accurate to 8 decimal places irrespective of the selected display format for volumetric values.


7955 2540 (Ch07C/AB) Page 7C.23


Objectives: • Read Indicated Volume total in 32-bit integer format.

Totals format


Register Access

Scaling Access


Registers Integer X Default Single None No Yes

Importantly, single register access is used – only one Gould Register is required to get a full value (i.e. all 16-bit data segments). Therefore, the Word Offset option has no effect. This example involves reading two whole integer values from two Gould Registers. Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1 and Single Register Access. Gould List Configuration Gould List Entry 1: <List1 Gould reg 1> = 1400 <List1 mapped loc 1> = 0174 (Indicated Volume total, whole part) * <List1 scale fact 1> = “No scaling” Gould List Entry 2: <List1 Gould reg 2> = 1401 <List1 mapped loc 2> = 0172 (Indicated Volume total, fractional part) * <List1 scale fact 2> = “No scaling”

* Parameter is not visible within the menu system. For a full location listing, contact factory. Action 1: Read whole value from Gould Registers 1400 and 1401

Transmit 06 03 05 78 00 02 45 69


Response 06 03 08 45 09 A0 00 3F 7D 0B 5C 51 09


Result • 4509 A000 is the 32-bit IEEE hexadecimal representation for 2202.0 (in base units of m3) • The first 8 bytes of data, 4509 A000, is the first and second 16-bit data segments (of the 32-bit value)

read from Gould Register 1400 (i.e. the integer part, 2202.0) • 3F7D 0B5C is the 32-bit IEEE hexadecimal representation for 0.98845457 (in base units of m3) • The last 8 bytes of data, 3F7D 0B5C, is the first and second 16-bit data segments (of the 32-bit value)

read from Gould Register 1401 (i.e. the fractional part, 0.98845457) Note: Fractional values of a rollover total are always accurate to 8 decimal places irrespective of the selected display format for the value.


Page 7C.24 7955 2540 (Ch07C/AB)


Objectives: • Read Indicated Volume total (Loc. ID: 0167) as a 64-bit (double-precision) floating-point value.

Totals format


Register Access

Scaling Access


Registers Fl. Point Double Default Single None No Yes

Importantly, single register access is used – only one Gould Register is required to get a full value (i.e. all four 16-bit segments). Therefore, the Word Offset option has no effect. This example involves reading the whole double-precision value from one Gould Register. Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, single register access, double-precision. Gould List Configuration Gould List Entry 1: <List1 Gould reg 1> = 1400 <List1 mapped loc 1> = 0167 (Indicated Volume total) <List1 scale fact 1> = “No scaling” Action 1: Read whole value from Gould Register 1400

Transmit 06 03 05 78 00 01 05 68


Response 06 03 08 40 A7 4F 14 44 35 79 DD 84 52


Result • 40A7 4F14 4435 79DD is the 64-bit IEEE hexadecimal representation for 2983.54 (in base units of m3) • The first 8 bytes of data, 40A7 4F14, is the first and second 16-bit data segments (of the 64-bit value)

read from Gould Register 1400 (i.e. the integer part, 2983) • The last 8 bytes of data, 4435 79DD, is the third and fourth 16-bit data segments (of the 64-bit value)

read from Gould Register 1400 (i.e. the fractional part to 8 decimal places) Note: Fractional values of a rollover total are always accurate to 8 decimal places irrespective of the selected display format for the value.


7955 2540 (Ch07C/AB) Page 7C.25

7C.3.11 Gould List Write Access: Example 1

Objective: Write 35.5 (°C) to Meter-run Temperature parameter (Loc. ID: 0666) as a 32-bit (single-precision) floating-point value.

Totals format


Register Access

Scaling Access



This example involves writing to two consecutive Gould Registers 1300 and 1301; this is to write two separate 16-bit values (35 and 5). Importantly, they are given consecutive entries in the Gould List. Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, multiple register access, single-precision. Gould List Configuration Gould List Entry 1: <List1 Gould reg 1> = 1300 <List1 mapped loc 1> = 0666 (Meter temperature) <List1 WordOffset 1> = “Word offset 0” <List1 scale fact 1> = “No scaling” Gould List Entry 2: <List1 Gould reg 2> = 1301 <List1 mapped loc 2> = 0666 (Meter temperature) <List1 WordOffset 2> = “Word offset 1” <List1 scale fact 2> = “No scaling” Action Write “35” (420E, IEEE hex.) to Gould Register 1300. Write “5” (0000, IEEE hex.) to Gould Register 1301

Transmit 06 10 05 14 00 02 04 42 0E 00 00 A3 CF

Meaning Slv. Fn. Reg. ID Reg. Cnt. D.C. Data Data Data Data EC LRC

Response 06 10 05 14 00 02 00 B7


Result • Echo of Gould Register address field, 1300 (0x0514), and Quantity field, 2 (0x02) indicate success.


Page 7C.26 7955 2540 (Ch07C/AB)


Objectives: 1. Write 50.2 (°C) to Meter-run Temperature parameter (Loc. ID: 0666) as a 32-bit (single-precision) value. 2. Write 3600.0 (m3/hour) to Corrected Volume flow rate (Loc. ID: 0144) as a 32-bit (single-precision) value.





This example involves writing to four consecutive Gould Registers 1300 - 1303; this is to write four 16-bit values (50, 2, 3600 and 0). Importantly, they are given consecutive entries in the Gould List. Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, multiple register access, single-precision. Gould List Configuration



Gould List Entry 3: <List1 Gould reg 3> = 1302 <List1 mapped loc 3> = 0144 (Corrected Volume flow rate) <List1 WordOffset 3> = “Word offset 0” <List1 scale fact 3> = “No scaling”

Gould List Entry 4: <List1 Gould reg 4> = 1303 <List1 mapped loc 4> = 0144 (Corrected Volume flow rate) <List1 WordOffset 4> = “Word offset 1” <List1 scale fact 4> = “No scaling” Action Write “50” (4248 in IEEE) to Gould Register 1300 and “2” (CCCD in IEEE) to Gould Register 1301 Write “360” (43B4 in IEEE) to Gould Register 1302 and “0” (0000 in IEEE) to Gould Register 1303

Transmit 06 10 05 14 00 04 08 42 48 CC CD 43 B4 Meaning Slv. Fn. Reg. ID Reg. Cnt. D.C. Data Data Data Data Data Data

Transmit 00 00 E9 1E

Meaning Data Data EC LRC

Response 06 10 05 14 00 04 80 B5




7955 2540 (Ch07C/AB) Page 7C.27


Objectives: 1. Write 50.2 (°C) to Meter-run Temperature parameter (Loc. ID: 0666) as a 32-bit (single-precision) value. 2. Write 3600.0 (m3/hour) to Corrected Volume flow rate (Loc. ID: 0144) as a 32-bit (single-precision) value.

Totals format


Register Access

Scaling Access


Registers X Single Default Single None No Yes

This is a variation of Example 2. Importantly, Single Register Access is used – only one Gould Register is required to get a full value (i.e. all 16-bit segments). Therefore, the Word Offset option has no effect. This example involves writing whole single-precision values to two Gould Registers. Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, single register access, single-precision. Gould List Configuration Gould List Entry 1: <List1 Gould reg 1> = 1300 <List1 mapped loc 1> = 0666 (Meter temperature) <List1 scale fact 1> = “No scaling” Gould List Entry 2: <List1 Gould reg 2> = 1301 <List1 mapped loc 2> = 0144 (Corrected Volume flow rate) <List1 scale fact 2> = “No scaling” Action Write “50.2” (4248CCCD in IEEE) to Gould Register 1300 Write “360.0” (43B40000 in IEEE) to Gould Register 1301

Transmit 06 10 05 14 00 02 08 42 48 CC CD 43 B4

Meaning Slv. Fn. Reg. ID Reg. Cnt. D.C. Data Data Data Data Data Data

Transmit 00 00 09 01

Meaning Data Data EC LRC

Response 06 10 05 14 00 02 00 B7




Page 7C.28 7955 2540 (Ch07C/AB)


Objectives: 1. Write 36000.0 (m3/hour) to Corrected Volume flow rate (Loc. ID: 0144) as a 32-bit (single-precision) value.

Totals format


Register Access

Scaling Access


Registers X Single Default Multiple x100 No Yes

Importantly with this example, the 36000.0 is de-scaled to be saved as 360.0. Since Multiple Register Access is to be used, two Gould Registers are required to write the full 32-bit value (i.e. two 16-bit data segments). Therefore, the Word Offset option is required. This example involves writing whole single-precision values – 36000.0 and 0.0 – to two Gould Registers. Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, Multiple Register Access, Single-precision. Gould List Configuration Gould List Entry 1: <List1 Gould reg 1> = 1300 <List1 mapped loc 1> = 0144 (Corrected Volume flow rate) <List1 WordOffset 1> = “Word offset 0” <List1 scale fact 1> = “Int (value x 100)” Gould List Entry 2: <List1 Gould reg 2> = 1301 <List1 mapped loc 2> = 0144 (Corrected Volume flow rate) <List1 WordOffset 2> = “Word offset 1” <List1 scale fact 2> = “No scaling” Actions 1. Write “36000.0” (470C in IEEE hexadecimal) to Gould Register 1300 2. Write “0.0” (A000 in IEEE hexadecimal) to Gould Register 1301

Transmit 06 10 05 14 00 02 04 47 0C A0 00 7A C3


Response 06 10 05 14 00 02 00 B7


Result • Echo of Gould Register address field, 1300 (0x0514), and Quantity field, 02 (0x02) indicates success.


7955 2540 (Ch07C/AB) Page 7C.29


Objectives: 1. Write 36000.0 (m3/hour) to Corrected Volume flow rate (Loc. ID: 0144) as a 32-bit (single-precision) value.

Totals format


Register Access

Scaling Access


Registers X Single Default Single x100 No Yes

Importantly with this example, the 36000.0 is de-scaled to be saved as 360.0. Since Single Register Access is to be used, only one Gould Register is required to write the full 32-bit value (i.e. all 16-bit data segments). Therefore, the Word Offset option is not used. This example involves writing a whole single-precision value, 36000.0, to a Gould Register. Serial Port Configuration Modbus default Word order, MODBUS (Base) Slave Address = 1, Single Register Access, Single-precision. Gould List Configuration Gould List Entry 1: <List1 Gould reg 1> = 1300 <List1 mapped loc 1> = 0144 (Corrected Volume flow rate) <List1 scale fact 1> = “Int (value x 100)” Action Write “36000.0” (470C A000 0000 0000 in IEEE) to Gould Register 1300

Transmit 06 10 05 14 00 01 04 47 0C A0 00 7A F0


Response 06 10 05 14 00 01 40 B6


Result • Echo of Gould Register address field, 1300 (0x0514), and Quantity field, 0001 (0x01) indicates success.


Page 7C.30 7955 2540 (Ch07C/AB)

‘INTELLIGENT TRANSMITTER’

MONITOR

(CHAPTER 7 ADDENDUM D)

Chapter 7D: ‘Intelligent Instrument’ Monitor Software Version 2540, Issue 4.30.00 (or higher)

Page 7D-2 7955 (Ch7D/AB)

Chapter 7D ‘Intelligent Transmitter’ Monitor

7D.1 Overview Chapter 7D is a guide to accessing process variables and diagnostic data from an ‘intelligent’ transmitter. The transmitter must have a communication port that supports RS-485 MODBUS® communications. Data read or written by the 7955 Flow Computer can be in integer or floating-point format. When a floating-point value is read, it can be ‘forwarded’ to user-specified target parameter (database location). In addition to this forwarding process, a floating-point value can be automatically re-scaled into alternative units. The monitoring feature operates with ‘intelligent transmitters’, such as the Micro Motion® Series 2000 (multivariable) digital transmitter (liquid) and Daniel Senior Sonic™ flow meter (gas). In the case of the Micro Motion® digital transmitter, it may require some pre-configuring. This is explained in Section 7D.2, along with a step-by-step procedure.

7D.1.1 Transmitter Monitor features

Features:

• Monitor on/off selection switch

• Polling method selection

• Polling interval selection

• Up to 32 registers for accessing 16-bit integer data of transmitter variables (and other data)

• Up to 16 registers for accessing floating-point data of transmitter variables (and other data)

• Forwarding of floating-point data to target parameters (database locations) with optional re-scaling * • Support for accessing registers in Message Blocks, as used by Daniel Senior Sonic™ flow meter

• Input alarm, “Modb fail slv” raised upon occurrence of communication error or time-out **

* An Input alarm, “Modb bad target”, is raised if target parameter is not in fixed list of parameters (Table 1, page 7D-4).

** The alarm message includes slave identification number (1-16) and activity (“R” – read failed or “W” – write failed).

7D.1.2 Where is the Transmitter Monitor in the 7955 menu system?

Figure 1 (below) shows how to navigate from the MAIN MENU to the TRANSMITTER MONITOR menu, and includes the keypad strokes needed to arrive at the menu. Apart from this menu, basic details of a 7955 serial port must also be configured. The menus for this task are located in the COMMUNICATIONS menu. Note: The full setting-up procedure is in Section 7D.3.

Configure

Other parameters

Communications

x3

ax5

a

b

Modbus master c

Transmitter monitor a

Note: Menus illustrated here are for release of software version 2540 at time of publication.

Figure 1: Navigation to the TRANSMITTER MONITOR menu

Software Version 2540, Issue 4.30.00 (or higher) Chapter 7D: Intelligent Instrument Monitor)

7955 (Ch7D/AB) Page 7D-3

7D.1.3 What is in the TRANSMITTER MONITOR menu?

Figure 2 shows a map of the menu and gives a briefing on the main elements. A more detailed explanation of each element follows the diagram, pages 7D-3 to 7D-6. Note: The full setting-up procedure is included in Section 7D.3.

Enable/disablePolling

RegistersMessage blocks

Monitor enableDisable

a

Monitor on/off selection screen.

bc

d

Further menus for detailing upto 32 Registers to handlevariables with integer values.

Further menus for detailing up to16 Registers to handle variableswith floating-point values.

TransmitterMonitor menu

a

b

Int registersFloat registers

Poll methodPoll interval

Polling menu leading toscreens for configuring pollmethod and polling interval.

Message block 1Message block 2Message block 3Message block 4

Message blocks menu leading to screensfor detailing up to 32 message blocks.

Message block 29Message block 30Message block 31Message block 32

x7x7


Figure 2: TRANSMITTER MONITOR menu map

Monitor On/Off Switch options are “Enable” or “Disable”.

• “Enable” – switches the Monitor on

• “Disable” – switches the Monitor off Monitor Polling Polling method options are “Optmize” (factory default) or “1 poll/reg”:

• “Optmize” – monitor will read registers at successive addresses in single poll

• “1 poll/reg” – monitor will read a single register at a time, working through listed registers one-by-one The factory default setting for the interval between polling is 2.0 seconds. This can be edited to be any period you require in whatever time units are selectable (seconds, minutes, hours, etc). If a value of 0.0 is entered, the polling is constant, but could affect cycle times.



Integer Register List

Each entry in the list comprises parameters to detail as follows:

• Value – If “Live”, integer value from transmitter shown. If status is “Set”, value is written to transmitter.

• Slave device – Select a MODBUS Slave Device record for the transmitter (see Section 7D.1.4)

• Register address – Enter full MODBUS register address of the transmitter variable (e.g. 40392)

• Message block – If supported by transmitter, select a Message Block (see page 7D-5 for details)

• Byte offset – Applicable only if using Message Block support (see page 7D-5 for details) Note: Forwarding and re-scaling support is not offered for integer values. Floating-point Register List

Each entry in the list comprises parameters to detail as follows:

• Value – If “Live”, raw value from transmitter shown. If status is “Set”, value is written to transmitter.

• Slave device – Select a MODBUS Slave Device record for the transmitter (see Section 7D.1.4)

• Register address – Enter the full MODBUS register address of a transmitter variable (e.g. 40392)

• Message block – If supported by transmitter, select a Message Block (see page 7D-5 for details)

• Byte offset – Applicable only if using Message Block support (see page 7D-5 for details)

• Target location – Enter location ID of parameter (Table 1), to which is forwarded the raw/post-scaled value

• Unit – Enter a code from Table 2 to identify units of Value. (If not listed, ignore and use Scale factor)

• Scaling factor – If needed, enter a multiplier factor to scale the raw value into base units for forwarding.

Table 1: Allowed target parameters (database locations)

Parameter Location ID

Line temperature 720

Line pressure 594

Prover inlet temperature 730

Prover outlet temperature 739

Prover inlet pressure 604

Prover outlet pressure 613

Density A temperature 749

Density B temperature 759

Header pressure 1543

Base density 354

Density A 288

Density B 306

Note: Attempts to enter any other location ID for Target Location will

result in an input alarm, “MODB bad target”.

If Value is in units that are not listed in Table 2 and the value is to be forwarded to a Target location, use Scaling factor to re-scale the forwarded value into base units. The setting for Unit is then ignored. If Value is in units that are listed in Table 2 and the value is to be forwarded to a Target location, select only the correct unit code for Unit and ensure that Scaling factor is set to 0.



Table 2: Codes for Unit parameter

Code Temperature Pressure Density 0 “Deg.C” (B) “bar abs” (B) “g/cc”

1 “Deg.F” “Pa abs” “g/litre”

2 “Kelvin” “kPa abs” g/m3”

3 “Ohms” “MPa abs” “kg/cc”

4 “Deg.R” “psia” “kg/litre”

5 (No units) “kg/cm2 abs” “kg/m3” (B)

6 (No units) “bar gauge” “tonnes/m3”

7 (No units) “Pa gauge” “oz/in3”

8 (No units) “kPA gauge” “oz/ft3”

9 (No units) “MPa gauge” “oz/barrel”

10 (No units) “psig” “oz/gallon (UK)”

11 (No units) “kg/c2 gauge” “oz/gallon (US)”

12 (No units) (No units) “lb/in3”

13 (No units) (No units) “lb/ft3”

14 (No units) (No units) “lb/barrel”

15 (No units) (No units) “lb/gallon (UK)”

16 (No units) (No units) “lb/gallon (US)”

17 (No units) (No units) “tons/ft3”

18 (No units) (No units) “tons/barrel”

19 (No units) (No units) “tons/gallon (UK”

20 (No units) (No units) “tons/gallon (US)”

(B) = Base units

Message Block List

The Daniel Senior Sonic™ transmitter is different to the Micro Motion® transmitter because it has registers grouped into blocks. In the operation manual for models 3400/3410/3420 (April 1998), there are 32 blocks of registers. Each block has a particular purpose and features multiple registers. For example, there is a Message Block 12 that has registers 350 - 398 for reading 48 calculation results, all floating-point values. On the 7955 Flow Computer, the 7955 Message Block List will allow read or write access to any part of any Message Block on the Daniel transmitter. Each entry in the list comprises parameters to detail an access: • Start register – address of first register in Daniel Message Block (e.g. 350, for Message Block 12)

• Byte size – enter size of Daniel Message Block in bytes: ((End register - Start register +1) x 2)

• Number of items – enter quantity of registers that equate to a full value As an example, consider reading register 392 (flow rate) from Daniel Message Block 12. The details to set-up on the 7955 Flow Computer are as follows: 1. Edit an entry in the Floating-point Register List

• Value – Ensure status is “Live” to see raw flow rate value from transmitter. * • Slave device – Select a MODBUS Slave Device record for the transmitter (see Section 7D.1.4)

• Register address – Not applicable when accessing Daniel Message Blocks.

• Message block – Select “Message Block 12”

• Byte offset – Select register to be accessed, 392, by entering an offset = (392 - 350) x 2 = 84

• Target location – Not applicable for this example.

• Unit – Not applicable for this example.

• Scaling factor – Not applicable for this example.

* When a value is “Set”, the value is written to the register. However, if the register is read-only, as in this case, the Daniel transmitter will accept it but the register value will simply not be changed.



2. Edit entry (record) 12 of Message Block List

• Start register – enter a value of 350

• Byte size – enter size of message block in bytes = [398 - 350 + 1) x 2] = 98

• Number of items – enter quantity of registers that equate to a full value (see note below)

7D.1.4 How to set-up a Slave Device record

A part of setting up the Transmitter Monitor is selecting a Slave Device record. The Slave Device record informs the 7955 Flow Computer (MODBUS Master) of what MODBUS slave it is going to be talking to and what communication settings it requires. Figure 3 (below) shows how to navigate from the MAIN MENU to the SLAVE DEVICES menu, with the keypad strokes needed to arrive at the menu. With the 7955 Flow Computer acting as the MODBUS Master, as in this case, a MODBUS Slave Device record must be detailed as follows:

• Device function – Select “Transmitter” option.

• Port number – Select the 7955 serial port connected to the transmitter.

• Slave device address – Enter numerical MODBUS address of the transmitter.

• Word ordering – Keep “Modbus default” (factory default), unless transmitter requires Word swap.

• Precision – Select “single” if accessing floating-point values that are 32-bit or “double” if 64-bit.

• Slave MODBUS commands – Select ‘Offset’ or ‘Full’ addressing method, as appropriate for transmitter.

• Other record details are not applicable. Note: The setting-up procedure is included in Section 7D.3.

Configure

Other parameters

Communications

x3

ax5

a

b

Modbus master c

Slave devices c


Figure 3: Navigation to the SLAVE DEVICES menu

The correct setting for Number of items will depend on the configuration of the 7955 serial port and the transmitter, in respect of data type and data size (16-bits, 32-bits or 64-bits) of the value involved. When the 7955 serial port is configured for a multiple-register access and single-precision (32-bit) floating-point value, enter a value of 2 for floating-point value or 1 for an integer value. When the 7955 serial port is configured for a multiple-register access and double-precision (64-bit) floating-point value, enter a value of 4 for floating-point value or 1 for an integer value. When the 7955 serial port is configured for single-register access, simply enter a value of 1.



7D.2 Preparing a Micro Motion® digital transmitter The following procedure is for preparing a Micro Motion® digital transmitter, Series 2000 multivariable, for MODBUS® digital communications with the 7955 Flow Computer. This procedure requires a serial cable, a RS232/RS485 converter and Micro Motion’s ProLink II TM transmitter configuration software on a PC.

Since the Series 2000 transmitter has a universal service port that supports other communication protocols, it must be configured to enable RS-485 MODBUS® communications. In addition to enabling this protocol, the baud rate must be changed from 38400 to 19200. (The minimum for the transmitter is 1200.) Procedure: 1. Using a suitable cable and a RS232/RS485 converter, interconnect the PC port (e.g. COM1) to

terminals 7 and 8 on the transmitter via the converter. RS485 Converter MicroMotion Transmitter Pin No: Terminal No: 2 7 7 8

2. Start the program ProLink II TM

3. Using Prolink II, establish communication between the PC and the transmitter through the menu <Connection><Connect to device>.

Select the options, as shown below, and then click on the "Connect" button. Note: This procedure might have to be repeated, as some RS232/RS485 converters do operate properly at the baud rate of 38400. Protocol: Select “Universal Service Port”. COM Port: Select “COM 1” (for PC port COM1).

4. Using ProLink II, configure the communication port of the transmitter

To do this:

• Select the menu <ProLink><Configuration> • Select the tab labelled "485 Comm" • Select the options shown below • Click on “Apply” – repeat this until there are no error messages.

Protocol: Select “Modbus RTU” Parity: Select “None” Baud Rate: Select “19200” Stop Bits: Select “1”

Note: Installation, operation, maintenance, etc. and safety instructions for the transmitter are outside the scope of this supplement and Flow Computer literature. For these details, refer to product literature of the transmitter. In addition, PC requirements for running ProLink II TM are outside the scope of this supplement and Flow Computer literature.



5. Terminate the program ProLink II TM 6. Using a suitable cable and a RS232/RS485 converter, connect the PC port (e.g. COM1) to terminals

5 and 6 on the transmitter. RS485 Converter MicroMotion Transmitter Pin No. Terminal No. 2 6 7 5

7. Using Prolink II TM, establish communication between the PC and the transmitter through the menu <Connection><Connect to device>. Select options, as shown below, and then click on the "Connect" button. Protocol: Modbus: Select “RTU (8-bit)” Baud Rate: Select “19200” Parity: Select “None” Connect via Address/Tag: Select “Address/Tag 1” COM Port: Select “COM 1” Stop Bits: Select “1”

8. Using Prolink II TM, ensure process variables (e.g. Density) can be viewed through the menu <ProLink><Process variables>

9. Terminate the program ProLink II TM.



7D.3 Configuring the 7955 Flow Computer Follow these instructions to configure and activate the Monitor on the 7955 Flow Computer: 1. Using a suitable cable, connect a 7955 serial port to the transmitter. Note: For details of the 7955

serial ports that support RS485, refer to main Chapter 7. Serial Port Micro Motion® Transmitter Pin No. Terminal No. (Rx/Tx+) 5 (Rx/Tx-) 6

2. Program the 7955 Flow Computer to be a MODBUS Master device

(2a) Navigate to this menu: <”Configure”>/<”Other Parameters”>/<”Communications”>/<”Ports”> (2b) Select a Serial Port menu, as appropriate for the serial port connected to the transmitter. (2c) Configure the basic communication parameters for that serial port, as shown in Table 3. (Some

localised menu navigation is required to find the parameter screen.) (2d) Navigate to: <”Configure”>/<”Other Parameters”>/<”Communications”>/<”Modbus master”> (2e) Configure the parameters, as shown in Table 4. (2f) Navigate to this sub-menu: <”Slave devices”> (2g) Select a Device menu (e.g. <”Device 1>) (2h) Configure the parameters, as shown in Table 5.

3. Program and activate the Monitor on the 7955 Flow Computer

(3a) Navigate to this menu: <”Transmitter monitor”> (3b) Configure the <Mon poll method> and <Mon poll interval> parameters. (3c) Navigate to the MESSAGE BLOCK menu (if applicable to transmitter) (3d) Select the first available message block menu (e.g. MESSAGE BLOCK 1 menu) (3e) Configure the parameters, as guided on page 7D-5 (3f) Repeat Steps 3c to 3e for all other message blocks to be detailed (3g) Navigate to the INT REGISTERS menu (if applicable) (3h) Select the first available register menu (e.g. INT REGISTER 1 menu) (3i) Configure the parameters, as guided on page 7D-4 (3j) Repeat Steps 3g to 3i for all other integer registers to be detailed (3k) Navigate to the FLOAT REGISTERS menu (if applicable) (3l) Select the first available register menu (e.g. FLOAT REGISTER 1 menu) (3m) Configure the parameters, as guided on page 7D-4 (3n) Repeat Steps 3k to 3m for all other integer registers to be detailed (3o) Configure <Monitor enable> parameter to show “Enable”






Setting

Comms port owner Select the multiple-choice option with “Modbus master”. “MODBUS slave”

Port Baud rate Keep the factory default, unless transmitter using lower baud rates. “19200”

Port char format Keep the factory default, unless transmitter using another format. “8 bits none 1 stop”

Port handshaking Keep the factory default setting. “None”

Port RS232 / 485 *** Select the RS485 signalling standard for the MODBUS network ** “RS 232”

Port Modbus mode Keep the factory default setting. “RTU”

P Modbus word order Keep the factory default setting. “Modbus default”

P MODB slave add (Not applicable) 1

P Modbus features (Not applicable) “None”

P long reg access Keep the factory default setting, unless using single-register access. “Multiple registers”

P MODB total format (Not applicable) “32-bit integer”

P MODB precision (Not applicable) “Single”

* The on-screen parameter descriptor includes a digit to identify the associated serial port.

** A 7955 may perform unexpected ‘restarts’ if it is configured to be “RS 232” when it should be “RS 485”.

*** Parameter is not applicable to serial ports that support RS-232 only.

Abbreviations used: “P” = Port, “reg” = register, “addr” = address, “char” = character, “MODB” = MODBUS

Table 4: MODBUS Master details

Parameter (Database Location) Instructions and Comments Factory Default

Setting

Length of timeout Keep the factory default setting. “0.5 second”

No of retries Keep the factory default setting. * “3 retries”

* If attempts to communicate with a slave are unsuccessful and exceed the maximum retries, an input alarm, “Modb failed slv”, is raised. The number of the slave 1 - 16 is given in the alarm message together with “R” (read failed) or “W” (write failed).

Abbreviation used here: “No” = number

Table 5: Slave device details


Setting

Slave device func Select “Transmitter” from the multiple-choice list. “None”

Slv device port no Select the 7955 serial port that is connected to the transmitter. “Comms port 1”

Slv device address Edit the numeric MODBUS address of the transmitter. 0

Device word swap Keep the factory default, unless transmitter requires Word swap “Modbus default”

Device precision Keep the factory default, unless floating-point value is 64-bit. “Single”

Slv modb commands Select “3,4, 16 addr offset” option for a Micro Motion® Transmitter ** “3, 16 full addr”

* The on-screen parameter descriptor includes a number to identify the slave device being detailed.

** The “offset” option applies where transmitters automatically add an offset (e.g. 40000) to get a register address specified in a

received MODBUS request. For transmitters that do not do this and require a full address, keep the factory default.

Abbreviations used: “func” = function, “Slv” = Slave, “no” = number, “modb” = Modbus

DUTY/STANDBY REDUNDANCY (HOT BACK-UP)

(CHAPTER 7 ADDENDUM E)

Chapter 7(e) Duty/Standby Redundancy Software Version 2540, Issue 4.30.00 (or higher)

Page 7e.2 Issue: AC

DUTY/STANDBY (HOT BACK-UP)

7E.1 WHAT IS THE PURPOSE OF THIS FEATURE?

The duty/standby facility allows for up to two 7955 flow computers to be connected together in an application where dual-redundancy is required. Duty/Standby controls the selection of a flow computer that is to be the main fiscal accounting device (‘Duty 7955’) and a flow computer that is to be the backup device (‘Standby 7955’). The hand-over may be automatic or manual.

7E.2 AUTOMATIC HAND-OVER Digital (status) inputs and outputs are utilised by both the ‘Duty 7955’ and ‘Standby 7955’ in the automatic selection process, as seen in Figure 1. In the event of any system alarm, such as those in Table 1, the status input-output link changes logic state to invoke a hand-over. On completion of the hand-over, the ‘Standby 7955’ becomes the ‘Duty 7955’. Once a hand-over has occurred, the new ‘Duty’ computer will raise an input alarm to indicate that a hand-over has occurred. The alarm message is “Dty/Stby handover”. As with all alarms, associated with this message will be a time and date stamp.

Table 1: System alarms that will invoke a hand-over

Power fail mA output no cal. Timeperiod no cal.

PRT no cal mA out cal fail. Database corrupt

mA input no cal. mA input cal fail. DBM bad triple.

DBM bad chksum. DBM power chksum. Battery failed.

Battery low. Density cal fail. Turbine no cal.

Figure 1: Status Input and Output arrangement

Flow computer 1: Flow computer 2:

WDop: Watchdog status output for system alarms on this flow computer. This status output goes true for 5 seconds after initialisation and remains true as long as the flow computer is functioning correctly.

DTop: Duty status output for this flow computer. This output is true whenever this flow computer is the

‘Duty 7955’ in the dual-redundancy scheme.

WDip: Watchdog status input from connected flow computer. This flow computer will become the ‘Duty 7955’ if this status input goes false.

DTip: Duty status input from connected flow computer. This flow computer will relinquish Duty control if

this status input goes true.

Input DTip

Output DTop

Input WDip

Output WDop

Output DTop Input DTip Output WDop Input WDip

Software Version 2540, Issue 4.20 (or higher) Chapter 7(e) Duty/Standby Redundancy

Issue: AC Page 7e.3


7E.3 INVOKING A MANUAL DUTY/STANDBY HAND-OVER

A menu location is provided to enable you to invoke the Duty/Standby hand-over either by the 7955 keypad, by an external supervisory system (RS-232/RS-485 MODBUS link) or by the result of a FC-Basic script. The menu location is toggled between “Be Duty” and “Be Standby”:

Be Duty – By making this location true within the ‘Standby 7955’ it will automatically become the ‘Duty 7955’. This is achieved by utilising the above input output arrangement.

Be Standby – By making this location go true within the ‘Duty’ flow computer it will automatically become the ‘Standby’ flow computer. This is achieved by utilising the above input output arrangement.

7E.4 FUNCTION TRANSFERS In addition to the hand-over of fiscal accounting control, the ‘Duty 7955’ will transfer other functions to the ‘Standby 7955’. With field instrumentation repeated to both 7955 flow computers, function transfers can include batch transactions, proving, PID control and valve control.

Proving Control (if supported in software)

Under Duty/Standby, a proving session can only be invoked by the ‘Duty 7955’. If the ‘Duty 7955’ is part of the way through a prove session when a failure occurs, the ‘Standby 7955’ will take over as the new ‘Duty 7955’. However, the new ‘Duty 7955’ will not able to continue in finalising the prove-session. Intervention by an operator or a MODBUS connected supervisory system will be required to start a new proving session. A hand-over INFO input alarm is raised by the new ‘Duty 7955’ and recorded in the Historical Alarm Log. As with all alarms, the time and date stamp is also recorded. This alarm can be read by an attached metering system, which can then invoke a new prove-session if required. The hand-over INFO alarm will not invoke a hand-over. Once a prove-session has been completed, the derived ‘Meter factor’ or ‘K-factor’ will be copied into the respective meter-run location in the ‘Duty 7955’. If configured, peer-to-peer communications will update locations in the ‘Standby 7955’. Note: Prover set-up data, such as prover type, limits, etc., will need to be configured into both the

‘Duty 7955’ and ‘Standby 7955’ flow computers. Note: Prover abort alarms are categorised into Input or Limit alarm types. This prevents an

occurrence of a hand-over if a prove-session has failed. Batch Control (if supported in software)

Under Duty/Standby, batch transactions are operated in the ‘Duty 7955’ and ‘Standby 7955’ in tandem. The ‘Duty 7955’ is responsible for controlling block valves and flow control valves (FCV). The ‘Standby 7955’ calculates the batch transaction in tandem to the ‘Duty 7955’. This will help ensure minimal loss of the batch count if a hand-over occurs. If a hand-over is invoked during a batch transaction, the ‘Standby 7955’ will continue to batch count. All valve control is passed to the new ‘Duty 7955’. Note: Under Duty/Standby, PID routines can run in the ‘Standby 7955’. This is achieved by sharing

the feedback loop current into the ‘Duty7955’ and ‘Standby 7955’ flow computers. Therefore, all of the control outputs will be repeated within the ‘Standby 7955’. If a hand-over occurs during a PID flow controlled batch transaction, the new ‘Duty 7955’ will continue to balance the flow through the configured meter-runs based on demand, until the batch is complete.


Page 7e.4 Issue: AC

DUTY/STANDBY (HOT BACK-UP) PID Control (if supported in software)

Under Duty/Standby, the ‘Duty 7955’ and ‘Standby 7955’ should be configured to perform the same measurement tasks. PID routines and settings should be the same, as these are specific to a field device such as a FCV (Flow Control Valve). The PID algorithm utilised for flow control is typically a closed-loop routine that requires feedback from the FCV in the field. Only the ‘Duty 7955’ will be connected to drive the FCV. It is possible to share the feedback signal from the FCV to the ‘Duty 7955’ and ‘Standby 7955’ via a signal splitter. This method will allow the two 7955 flow computers to calculate the required drive output but only the ‘Duty’ computer drive output will be connected to the FCV. Note: PID parameters, such as the target control variable, can be copied to the ‘Standby 7955’ using

peer-to-peer communications. When a hand-over is invoked, external relay logic can be used to connect the new ‘Duty 7955 to the FCV and therefore drive the valve as required. The relay logic may be driven though a user configured status output that indicates if the flow computer is the ‘Duty 7955’. (For further information on the relay logic required, contact the factory using the details on the back page.) Valve Control (if supported in software)

Under Duty/Standby, all valve related status inputs and outputs should be connected to both the ‘Duty 7955’ and ‘Standby 7955’ flow computers. External relay logic will be needed to ensure valve drive inputs and outputs are switched to the ‘Duty 7955’’. Valve status inputs can be connected directly to the ‘Duty’ and ‘Standby’ flow computers. (For further information on the relay logic required, contact the factory using the details on the back page.) Fiscal Total Synchronisation

A feature of Duty/Standby is to provide synchronisation of fiscal totals. The totals from the ‘Duty 7955’ are copied to the ‘Standby 7955’ in one of two ways:

1. When the ‘Standby 7955’ is initially powered up. This is to ensure the totals have been synchronised if a double hand-over occurs within a periodic interval period.

2. At a periodic time interval configurable by the user. This is to prevent the two flow computers from drifting apart, e.g. if an analogue input slightly out, particularly from a flow meter analogue output.

<Configure><Duty Standby><Total Sync><Total sync period> The periodic time interval is configurable by the user to one of the following options:

“Disable”, “1 minute”, “2 minutes”, “5 minutes” {default}, “10 minutes”, “15 minutes”, “20 minutes”, “30 minutes”, “1 hour”, “2 hours”, “3 hours”, “4 hours”, “6 hours”, “8 hours”, “12 hours” and “24 hours”

NOTE: If the period time interval is set to “inactive”, the totals will only be updated when the ‘Standby 7955’

initially comes on-line.

There are three different options when configuring duty standby:

“Disabled” – Duty standby operation disabled. (Factory default setting).

“Enabled without totals” – No synchronisation of totals during duty standby operation, but peer list active

“Enabled with totals” – Automatic total synchronisation between Duty and Standby 7955 and peer list is active. Totals synchronisation will be carried out automatically over the peer link, and will take place after the user specified time interval has elapsed and at the next execution of the peer link data transfer. The totals do not require configuration into a peer list. However, other data for example Meter factor (MF), Batch size, etc. requires configuration into the peer list. (User list 1)


Issue: AC Page 7e.5

DUTY/STANDBY (HOT BACK-UP) Before the fiscal totals can be transferred to the ‘Standby 7955’, the ‘Duty 7955’ has to write to a location which will allow the totals to be overwritten via the peer-to-peer communication link. Once the totals have been updated on the Standby 7955, the location is reset, and in doing so protecting the fiscal totals from any other communication activity. A user option menu will allow the user to select which combination of Stream totals, Station totals and Net flow totals are synchronised across the peer link. NOTE: Fiscal totals will only be written to if option 3 above is also configured.

7E.5 USAGE OF PEER TO PEER COMMUNICATIONS

Under Duty/Standby, peer-to-peer communications is utilised by the ‘Duty 7955’ to keep the ‘Standby 7955’ up-to-date with data. (You may wish to read Addendum 7A for a full description of peer-to-peer support.) Duty/standby usage of the peer-to-peer function utilises List One of the two peer-to-peer parameter lists. The ‘Duty 7955’ is considered to be the master and the ‘Standby 7955’ is the slave. Note: Data will flow in one direction only – from MODBUS master to the MODBUS slave. When a hand-over occurs, the new ‘Duty 7955’ will become the MODBUS master on the Duty/Standby communications link. The ‘Duty 7955’ will enable the peer link within itself and the new ‘Standby 7955’ will switch off the peer link within itself to inhibit communications contention. The duty/standby function can also be configured to swap the slave addresses of user selected communications ports. This feature is particularly useful in metering systems applications whereby only the ‘Duty’ flow computer is required to communicate with the supervisory computer.

Note: Slave address swapping is unavailable when using Ethernet. In the example below, two flow computers are configured for a Duty/Standby application. Serial ports 1 and 2 are utilised by supervisory computers. Serial port 1 is connected to one system and Port 2 is connected to the other. The two supervisory systems may also be operating a duty/standby function between themselves. Configure the Duty slave address and the Standby slave address for each communications port using the following menu: <Configure><Other parameters><communications><Port n > Where n is the port number. Flow computer communication port addresses would be changed when a hand-over occurs to ensure that the supervisory computer system always accesses data from the ‘Duty’ flow computer.

Port 1 Slave add #1 Port 2 Slave add #2 Duty Computer

Port 1 Slave add #3 Port 2 Slave add #4 Standby Computer


Page 7e.6 Issue: AC


7E.6 CONFIGURING THE 7955 FLOW COMPUTER FOR DUTY/STANDBY. The following will guide the user through the necessary steps to configure the flow computer to perform Duty/Standby. The approach to configuring this feature should be considered carefully. You must decide which flow computer is to be the ‘Duty’ and which is to be the ‘Standby’. The cabling between the two flow computers must be connected. It is advisable that configuring the Duty/Standby feature is carried out systematically, performing simple verification tests after each step. The worked example will show how to perform these configuration steps and the tests.

Step 1. Connect Duty/Standby cabling. This example use status inputs 6 / 7 and status output 10. At this stage, ensure that the DutyStandby enable location is set to Disable.

<Configure><Duty Standby><Duty/stndby Enable>…Set to Disable

This will ensure that during commissioning of the inputs, the two flow computers will not ‘hunt’ between duty and standby operation.

Figure 2: Duty/Standby connection drawing.

SK2-8

WDip (ip#6)WDip (ip#6)

DTip (ip#7)DTip (ip#7)

DTop (op#10)DTop (op#10)

1 KΩ 1 KΩ

+24 Volt

1 KΩ

N/O Relay

+24 Volt

Alarm Common

+24 Volt

1 KΩ

N/O Relay

+24 Volt

Alarm Com

0 Volt 0 Volt

0 Volt

0 Volt

0 Volt

0 Volt

WDop from Relay

SK2-9

SK2-46

SK2-14

SK2-34 SK2-34

SK2-14

SK2-46

SK2-9

SK2-8

SK3-35 SK3-35

SK3-34 SK3-34

SK3-1 SK3-1

SK3-3 SK3-3

SK3-20 SK3-20

SK3 SK3

SK2SK2


Issue: AC Page 7e.7

DUTY/STANDBY (HOT BACK-UP) Notes: • Status input and Status output common returns must be connected to 0V power. • Resistor values are 1Kohm. • System Alarm Relay output is used in the NC mode.

To ensure that the flow computer executes a hand-over during a power outage on the Duty system, some of the status inputs and outputs must be configured to be either positive or negative logic sense. The Duty status input (Dtip Input #7) must be set to negative logic sense:

<Configure><Status Inputs><Status Input n><Logic sense>

The Duty status output (DTop output #10) must be set to positive logic sense using:

<Configure><Outputs><Status Outputs><Status output n><status output n logic>

The watchdog output (WDop) is from the NC (Normally Closed) ‘system alarm’ relay output.

Step 2. With the cable connected, each 7955 flow computer must now be configured. The Duty/Standby feature must have the inputs and outputs defined under the following menu:

<Configure><Duty standby><I/O allocation>

Configure the Duty Input to be from Status input #7. Remember this input is to be negative logic input sense.

Configure the Duty output to be from Digital output #10. Remember this output is to be positive logic output.

Configure the Watchdog input to be from Status input #6. This status input is positive logic input sense.

It is advisable to configure the multi-view facility such that one of the pages displays the relevant locations for Duty/Standby operation. This will be an aid when commissioning the flow computer to perform this task. Use the following table:

Menu name Modbus ID number Comments

Duty Stby Mode 4956 Add to line 1 of multi-view page

Status i/p 0196 Add to line 2 of multi-view page

Duty standby state 4959 Add to line 3 of multi-view page

Status o/p 0199 Add to line 4 of multi-view page

Once the multi-view page has been configured and steps 1 and 2 have been completed, the Duty/Standby feature can be tested. Set-up both flow computers to be a Standby by accessing the multi-view page line 3 and toggle the option to Be Standby. This forces both the flow computers to be a Standby and will help to prevent hand-over ‘hunting’ Once this is completed, the Duty/Standby feature in one flow computer can be enabled. <Configure><Duty Standby<Duty/Stndby Enable>……Select the option Enable no totals. This flow computer will now assume the task of ‘Duty 7955’. Once the ‘Duty 7955’ is running as Duty, the Duty/ Standby feature should be enabled on the other flow computer – this flow computer will be forced into the Standby role by the current Duty 7955. Duty/Standby will now be operating and can be tested. A Duty/Standby hand-over can be invoked via the multi-view page line 3. In the Duty 7955, change the option under this location from Idle to Be Standby. The ‘Duty 7955’ will now become the ‘Standby 7955’ whilst the ‘Standby 7955’ becomes the new ‘Duty 7955’.


Page 7e.8 Issue: AC


Step 3. When the flow computers are running Duty/Standby, the ‘Duty 7955’ will periodically update the ‘Standby 7955’ via the Peer to Peer communication link with the contents in Peer List 1. This list can be configured as explained in Chapter 7B. This can also be tested during commissioning to ensure correct operation. This is usually accomplished by setting a process variable that is defined in the peer list and observing it is transferred across to the ‘Standby 7955’ at the configured cyclic rate (e.g. every cycle). Note: The peer transfer of data and totals will not be carried out whilst the ‘Standby 7955’ is powered down. If a hand-over has occurred, due to failure of the ‘Duty 7955’, the new Duty will wait to see that new Standby is running before it starts to transfer data and totals. This is accomplished by the ‘Duty 7955’ monitoring the watchdog input (WDip). However, it is advisable to remove the metering system communications (not the peer link) from any repaired flow computer before it is powered up as the new standby. This will help to ensure that the connected metering system does not inadvertently access the new Standby in assuming it is the true Duty.

Step 4. The Duty/Standby feature allows the ‘Duty 7955’ to update to fiscal totals in the ‘Standby 7955’. The following totals can be up-dated: stream totals, station totals and net totals. The update of totals on the ‘Standby 7955’ will only be done when the respective stream is in the ‘flowing’ mode. The following menu option allows the user to configure flow computer.

<Configure><Duty Standby><Total Sync> For a quad-stream system, whereby the flow totals need updating on the Standby, the following must be configured:

<Configure><Duty Standby><Total Sync><Stream total sync>…for streams 1, 2, 3 and 4.

<Configure><Duty Standby><Total Sync><Station total sync>…select yes. If using the ultrasonic flow metering support, whereby the reverse flow totals need updating on the Standby, the following must be configured:

<Configure><Duty Standby><Total Sync><Usonic rev tsync>…select yes. This facility can be tested by setting the ‘Duty 7955’ into the flowing mode for all streams. This is achieved by ensuring that the input frequency signal for turbines is above the low flow cut off. Set nominal test flow rates into the ‘Duty 7955’ and ensure that it is totalising. Monitor the ‘Standby 7955’ and observe the flow totals updating in the Standby as per the configured total sync period.

Chapter 8 Alarms and events

7955 2540 (Ch08/AC) Page 8.1

8. Alarms and Events

8.1 Alarms

8.1.1 Alarm types The types of alarms which are detected and recorded are:

System alarms, caused by one or more of:

• Power failure

• Battery low (if a battery is fitted)

• Watchdog

• RAM checksum failure

• ROM checksum failure

Input alarms, caused by one or more of:

• Failure of analogue inputs

• Failure of density transducers

• Incorrect data has been entered

Limit alarms, caused by one or more of:

• Limits which you have set

• Limits defined by the system

These always result in two alarms - one when the change first happens and another when the system returns to its normal state.

8.1.2 Alarm indicators The 7955 has three LED indicators (one each for Input, System and Limit Alarms) to show alarm status.

Each alarm indicator can be in one of three states:

Off The system is working normally.

Flashing An alarm has been received but has not yet been accepted.

On All alarms has been accepted but not yet cleared. The conditions which caused the alarms in the first place may still exist.

1. System alarm 2. Input Alarm 3. Limit Alarm

Figure 8.1: Alarm indicators on the front panel


Page 8.2 7955 2540 (Ch08/AC)

8.1.3 How alarms are received and stored When a new alarm is received, the appropriate indicator LED on the front panel starts flashing. If the indicator is already flashing because of a previous alarm, it continues to do so. If the indicator is already ON (steady), it starts to flash.

Information about alarms is stored in two logs:

This gives: • The Alarm Status Display (1) a summary of the contents of the Historical Alarm Log (2) an indication of the current status of the system.

• The Historical Alarm Log This contains an individual entry for every alarm stored in the log.

The Historical Alarm Log can store up to 30 entries. When a new alarm is received, one of two things can happen:

If the Historical Alarm Log is NOT full : An entry for the new alarm is simply added to the list.

If the Historical Alarm Log is full : It depends on how the system is set up: Either (1) the oldest entry is deleted and the new one is added to the top of the list, or (2) the new alarm is discarded. In either case, the Status Display is updated automatically.

8.1.4 Examining the Alarm Status Display and Historical Alarm Log Press the INFORMATION button If you want to examine the Alarm Status Display or the Historical Alarm Log.

• To bring up the Alarm Status Display, select the Alarm Summary option.

• To bring up the first entry in the Historical Alarm Log, select the Alarm History option.

Figure 8.2: How to get to the alarm log


7955 2540 (Ch08/AC) Page 8.3

8.1.5 What the Alarm Status Display tells you A typical Alarm Status Display is shown in the Figure 8.2. The display lists, for each type of alarm (System, Input or Limit), the number of alarms which are live and new.

• New alarms are alarms which have been received but not yet accepted. • Live alarms are alarms which refer to conditions which are still active.

An example of a live alarm is when there is a fault in the system. This produces two alarms - one when the fault first occurs (‘ON’) and the second when it is put right (‘Off’). If only the first alarm of the pair has been received, the alarm is said to be live because the condition still exists.

The number of live alarms tells you how many faults are still active. If you look at the Historical Alarm Log this tells you more about these faults.

8.1.6 What the entries in the Historical Alarm Log tell you The diagram, below, shows the function of the relevant keys, and what is on the display.

Key to figure: 1. Indicates if there are entries BEFORE this one.

2. Alarm is either ‘ON’ (fault occurrence) or ‘OFF’ (fault cured).

3. Type of alarm.

4. Indicates alarm not accepted.

5. Accept this alarm.

6. Extra identifier to qualify the alarm description.

7. Clear this alarm entry

8. Date and time that this alarm (message) was raised.

9. Identifies a metering-run (stream).

10. Indicates that there are alarm entries AFTER this one.

11. Scroll DOWN through the entries.

12. Description of alarm.

13. Scroll UP through the alarm entries.

14. Clear all alarm entries.

Each alarm has its own entry in the Historical Alarm Log which tells you:

• Type of alarm

Whether it is a System alarm, Input alarm or Limit alarm and if the alarm is ‘on’ or ‘off’.

• Extra identifier for the alarm

This is not always shown for every entry but, where it is shown, it could be one of the following:

• A digit This indicates the channel number on which the fault occurred.

• A letter H and L are for high and low Limit alarms, S is for a step alarm.

• Date and time

The date is in the format DD-MM-YY and the time HH:MM:SS. These are entered automatically by the system when the alarm is received. The time is accurate to within one second.

• Acceptance indication This is only shown for those entries which have not been accepted. When the entry is accepted, the indicator disappears.

• Other entries indication

An up-arrow symbol shows that there are entries before the present one, a down-arrow symbol shows that there are others after. If the entry currently shown is first in the list, there is no up-arrow. If it is last, there is no down-arrow.

• Description of the alarm

This is an abbreviated description of the alarm and should be sufficient to help you trace the cause of the problem. A full list of all alarm messages and what they mean, are listed on page 8.3.

Figure 8.3: A typical entry in the log


Page 8.4 7955 2540 (Ch08/AC)

8.1.7 Clearing all entries in the Historical Alarm Log To clear all the alarm entries in the Historical log, press the CLR key. This clears all entries in the Historical Alarm Log, zeroes the entries in the Status Display and sets all LED indicators to OFF.

8.1.8 User-defined Alarms There are several types of user-defined alarms :-

User-defined Alarms 1st page

User Alarm Type 1: ‘Measurement’ Limit Alarm 8.4

User Alarm Type 2: ‘Comparison’ limit alarm 8.5

8.1.8.1 User Alarm Type 1: ‘Measurement’ Limit Alarm User limit alarms (nominated as ‘W’, ‘X’, ‘Y’ and ‘Z’) are available for monitoring values of any parameters that do not have low/high alarm limits.

Configuring involves:

1. Editing the identification number of the parameter (menu data) to be monitored by the 7955 2. Editing values for the high and low limits

IMPORTANT NOTICE We recommend using the 7955 set-up Wizard, “Alarms”, when configuring these alarms. Wizards are described in Chapter 10.

• Configuration task (User Limit Alarm)

Follow these instructions if you want to configure without using a Wizard.

1. Navigate to the menu data page of the parameter to be monitored and then press the ‘a’ soft-key once to display the database location identification (ID) number. Make a note of that number.

2. Navigate to this menu: <“Configure”>/<“Other parameters”>/<“Alarms”>

3. Locate and edit parameters as shown in Table 8.1

Table 8.1: User Limit Alarm Parameters


User alarm ptr. • Edit the value to be the ID number of the parameter to be monitored. The number will be replaced with the associated data name if the parameter exists. Note: Default setting is 0000 (“Off”) - not in use

User alarm HI lmt • ‘Set’ the maximum allowed value for the selected parameter.

User alarm LO lmt • ‘Set’ the minimum allowed value of the selected parameter.

* On-screen descriptions include an extra letter to identify the alarm nomination.

• Summary

The up-to-date state of all user-defined alarms is shown in this menu: <“Health check”>/<“User Alarms”>. User Alarms each have a dedicated digit:

‘0’ = Not in use/No Alarm/Alarm accepted ‘1’ = Alarm active


7955 2540 (Ch08/AC) Page 8.5

8.1.8.2 User Alarm Type 2: ‘Comparison’ limit alarm User comparison alarms (nominated as ‘A’, ‘B’, ‘C’ and ‘D’) are available for comparing values of two software parameters and raising an alarm when the difference is outside a ‘Set’ limit.

Configuring involves:

1. Editing the identification numbers of the two parameters (menu data) to be monitored

2. Editing a value for the comparison limit

IMPORTANT NOTICE

We recommend using the 7955 set-up Wizard, “Alarms”, when configuring these alarms. Wizards are described in Chapter 10.

• Configuration task (User Comparison Alarm)

Follow these instructions if you want to configure without using a Wizard.

1. Navigate to the menu data pages of the two parameters to be compared. Use the ‘a’ soft-key to display the database location identification (ID) number. Make a note of each ID number.

2. Navigate to this menu: <“Configure”>/<“Other parameters”>/<“Alarms”>

3. Locate and edit parameters as shown in Table 8.2

Table 8.2: User Comparison Alarm Parameters


Comp alarm ptr1 • Edit the value with the ID number of the first parameter to be used in the

comparison. The number will be replaced with the associated menu data name (if the parameter exists). Note: Default setting is 0000 (“Off”) - not in use

Comp alarm ptr2

• Edit the value line with in the ID number of the second parameter to be used in the comparison. The number will be replaced with the associated menu data name (if parameter exists).

Note: Default setting is “Off”. (i.e. not in use)

Comp alarm limit

• ‘Set’ the maximum allowed difference between values of the two parameters without needing to raise an alarm.

Note: Default limit is 0 – feature is switched off

* On-screen descriptions include an extra letter to identify the alarm nomination

• Summary

The up-to-date state of all user-defined alarms are shown in this menu:<“Health check”>/<“User Alarms”> User Comparison Alarms each have a dedicated digit:

‘0’ = Not in use/No Alarm/Alarm accepted ‘1’ = Alarm active


Page 8.6 7955 2540 (Ch08/AC)

8.1.9 Alarm Logger Output (ALO) Status Outputs 1 to 4 are dedicated to indicating the presence of active alarms. By default, the ALO is enabled and pre-configured as shown in Table 8.3.

Table 8.3: ALO Default Set-up

Digital Output Default Function

Status Output 1 • Indicate System Alarms only

Status Output 2 • Indicate Limit Alarms only * Status Output 3 • Indicate Input Alarms only

Status Output 4 • Indicate User Limit Alarms

* User Comaprison Alarms ‘A’ and ‘B’ are also indicated

ALO Re-configuration Options ALO use of the first three Status Outputs can be re-configured at any time by changing the selected alarm grouping. Parameters for making a change are found within the menu system.

To change the alarm grouping… 1. Navigate to this menu: <”Configure”>/<”Other parameters”>/<”Alarms”>/<”Alarm logger”>

2. Locate parameters as identified in Table 8.4 and change the alarm grouping option to suit your requirements. Available options are summarised in Table 8.5.

Table 8.4: ALO Configuration Parameters

Menu Data (as displayed) Purpose of Configuration Parameter

Alarm output 1 • Show/Change alarm group for Status Output 1



Table 8.5: Alarm Grouping Options

Option Purpose of option

None • Do not indicate presence of any alarms *

System • Indicate System alarms only

Input • Indicate Input alarms only

Limit • Indicate Limit alarms only

Any • Include System, Input and Limit alarms.

System Input • Indicate System alarms and Input alarms

System Limit • Indicate System alarms and Limit alarms

Input Limit • Indicate Input alarms and Limit alarms

* This does not free up the digital (status) output for another function Notes: 1. For further information on Digital (Status) Outputs, refer to Chapter 2 and Appendix ‘C’.

2. The presence of active User-defined Comparison Alarms (‘A’, ‘B’, etc.) are also indicated by status outputs nominated to include Limit Alarms.


7955 2540 (Ch08/AC) Page 8.7

8.1.10 Alarm Message List

* Alarm can be cleared immediately

Base Alarm Message

Alarm Type What the “ON” alarm message means

4x5 Oil dens fail Input Oil density (by 4x5 referral) can not be calculated. Check all associated parameters. Extra Message Character: “P” = Prime measurement, “M” = Metering measurement

5167 orif dia lmt Limit Orifice diameter is outside a limit as defined in the chosen ISO 5167 Standard. Extra Message Character: “H” = High limit, “L” = Low limit

5167 pipe dia lmt Limit Pipe diameter is outside a limit as defined in the chosen ISO 5167 Standard. Extra Message Character: “H” = High limit, “L” = Low limit

Alarm total limit Limit Alarm condition total has reached the programmed (SET) rollover-to-zero limit. Extra Message Character: none = Normal mode (main) total, “M” =Maintenance mode total, “T”/ “B” = Batch total

API Oil dens fail Input Oil density (by API referral) can not be calculated. Check all associated parameters. Extra Message Character: “P” = Prime measurement, “M” = Metering measurement

Archive format * System Archive formatting operation unsuccessful. Check all size associated parameters.

Archive too small * System Insufficient space for archiving. Check all size associated parameters.

Base BSW limit Limit BSW % at base conditions is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Base den API fail Input API referral calculation for base density was unsuccessful. Check all associated configurable parameters using reference pages in Chapter 11. Extra Message Character: “F” = Forward referral stage, “R” =Reverse referral stage

Base dens limit Limit The Base Density measurement value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Battery failed System Configuration has been lost. Replace the battery as instructed in Chapter 14.

Battery low System Replace the battery as instructed in Chapter 14. (Configuration is safe for moment)

Brooks:10 run lmt * Limit Maximum number of prove runs restored to 10 runs - the maximum allowed for Brooks Compact Proving

BSW comp limit Limit (A#B) The calculated difference between BSW measurement channels (‘A’ & ‘B’) is beyond the programmed (SET) comparison limit.

Comparison limit Limit General user-defined limit alarm. Extra Message Character: “A” = User Alarm ‘A’, “B” = User Alarm ‘B’, etc.

Database corrupt * System Corruption occurred but has been fixed automatically. Always seen when software has just been installed. Check all configured parameters If seen at any other time.

DBM bad chksum * System There has been an unrecoverable memory checksum failure. The Flow Computer will need to be re-configured. Extra Message Character: ‘V’ = Volatile (RAM), ‘N’ = Non-volatile (FRAM)

DBM bad triple * System

Corruption of the database in a memory area occurred but there has been an automatic recovery. (‘0’ is often seen after installing new release of same software version) Extra Message Character: ‘0’ = RAM copy, ‘1’=1st. non-volatile memory copy, ‘2’=2nd. Non-volatile memory copy, ‘3’ = Padding, ‘!’ = Beyond repair / Re-configure Flow Computer

Dens 4x5 fail Input Metering Density by 4x5 matrix referral calculation was unsuccessful. Check all associated configurable parameters using reference pages in Chapter 11.

Dens API fail Input Metering Density by API referral calculation was unsuccessful. Check all associated configurable parameters using reference pages in Chapter 11.

Density cal fail System Calibration of Time Period Input unsuccessful. Extra Message Character: “1” = Time Period Input ‘1’, “2” = Time Period Input ‘2’, etc.

Dens comp limit Limit (A#B) The calculated difference between density measurement channels (‘A’ & ‘B’) is beyond the programmed (SET) comparison limit.


Page 8.8 7955 2540 (Ch08/AC)

(Alarm Message List continued…) * Alarm can be cleared immediately

Base Alarm Message


Dens press limit Limit ‘Density loop’ pressure measurement value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit

Dens temp A limit Limit ‘Density loop’ fluid temperature measurement channel ‘A’ value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit

Dens temp B limit Limit ‘Density loop’ fluid temperature measurement channel ‘B’ value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit

Dens txdr calc Input

A density (transducer) measurement channel value has a “Fail” status. Check the physical connections with the transducer and use the “Health check” menu to monitor the associated Time Period Input. Extra Message Character: “A” = Density ‘A’, “B” = Density ‘B’

Dens txdr limit Limit The prime density measurement value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Diff press limit Limit Differential pressure measurement value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit

DLG list non-real * Input Archive lists only allow software parameters with floating-point values.

Dynamic visc calc Input

A dynamic viscosity measurement channel value has a “Fail” status. Check the physical connections with the transducer and use the “Health check” menu to monitor the associated Time Period Input. Extra Message Character: “A” = Dynamic Viscosity ‘A’, “B” = Dynamic viscosity ‘B’

Dyn visc compare Limit (A#B) The calculated difference between measurement channels (‘A’ & ‘B’) is beyond the programmed (SET) comparison limit.

Dyn visc limit Limit Dynamic viscosity measurement value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Gross std vol lmt Limit Gross Standard Volume flow rate is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Gross vol limit Limit Gross Volume flow rate is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

GSV total limit Limit Gross Std. Volume flow total has reached the programmed (SET) rollover-to-zero limit. Extra Message Character: none = Normal mode (main) total, “M” =Maintenance mode total, “T”/ “B” = Batch total

GV total limit Limit Gross Volume flow total has reached the programmed (SET) rollover-to-zero limit. Extra Message Character: none = Normal mode (main) total, “M” =Maintenance mode total, “T”/ “B” = Batch total

HART input fail Input

A HART Input menu data (location) page has a “Fail” status. The Flow Computer is not presently receiving information from a HART protocol transmitter. Check the HART network loop connection and monitor the HART Input using the “Health Check” menu. Extra Message Character: “1” = HART Input ‘1’, “2” = HART Input ‘2’, … , “8” = HART Input ‘8’

HSL addr conflict System High Speed List address conflict due to a HSL block overlapping. Extra Message Character: “A” = Block ‘A’, “B” = Block ‘B’, … , “F” = Block ‘F’

Ind std vol limit Limit Indicated Standard Volume flow rate is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

ISO5167 beta lmt Limit Beta ratio is outside a limit as defined in the chosen ISO 5167 Standard.

ISO5167 ReD limit Limit Reynolds number is outside a limit as defined in the chosen ISO 5167 Standard.

ISV total limit Limit

Indicated Standard Volume flow total has reached the programmed (SET) rollover-to-zero limit. Extra Message Character: none = Normal mode (main) total, “M” =Maintenance mode total, “T”/ “B” = Batch total


7955 2540 (Ch08/AC) Page 8.9


Base Alarm Message


IV total limit Limit Indicated Volume flow total has reached the programmed (SET) rollover-to-zero limit. Extra Message Character: none = Normal mode (main) total, “M” =Maintenance mode total, “T”/ “B” = Batch total

Kin visc compare Limit (A#B) The calculated difference between measurement channels (‘A’ & ‘B’) is beyond the programmed (SET) comparison limit.

Kin visc limit Limit Kinematic viscosity measurement value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

mA input cal fail Input Calibration of mA (Analogue) Input unsuccessful. Extra Message Character: “1” = Analogue Input ‘1’, “2” = Analogue Input ‘2’, … , “a” = Analogue Input ‘10’

mA input failed Input

An Analogue Input channel menu data (location) page has a “Fail” status. The Flow Computer is not presently receiving valid signals from a loop-powered transmitter. Check physical connections and monitor the input using the “Health Check” menu. Extra Message Character: “1” = Analogue Input ‘1’, “2” = Analogue Input ‘2’, … , “a” = Analogue Input ‘10’

mA input no cal System Analogue Input not calibrated. Contact the factory for advice. Extra Message Character: “1” = Analogue Input ‘1’, “2” = Analogue Input ‘2’, … , “a” = Analogue Input ‘10’

mA out cal fail System Calibration of mA (Analogue) Output unsuccessful. Extra Message Character: “1” = Analogue Output ‘1’, “2” = Analogue Output ‘2’, etc.

mA output failed Output An Analogue Output channel menu data (location) page has a “Fail” status. There is a hardware problem with the Flow Computer. Contact the factory for advice. Extra Message Character: “1” = Analogue Output ‘1’, “2” = Analogue Output ‘2’, etc.

mA output no cal System Analogue Output not calibrated. Contact the factory for advice. Extra Message Character: “1” = Analogue Output ‘1’, “2” = Analogue Output ‘2’, etc.

Mass limit Limit Mass rate is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Mass total limit Limit Mass flow total has reached the programmed (SET) rollover-to-zero limit. Extra Message Character: none = Normal mode (main) total, “M” =Maintenance mode total, “T”/ “B” = Batch total

Mass water% limit Limit Percentage of ‘water’ in oil/water mix (by mass) is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Meter BSW limit Limit BSW % at metering conditions is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Meter press limit Limit The metering pressure measurement value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit

Meter temp limit Limit The metering temperature measurement value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit

MODB slave clash System Serial Port configuration conflicts with the configuration of another port Extra Message Character: “1” = Serial Port ‘1’, “2” = Serial Port ‘2’, etc.

Oil SG limit Limit Specific gravity of the metered oil is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Orif ISO5167 lmt Limit The ISO 5167 Standard calculation was unsuccessful. Check all Orifice System parameters using reference pages in Chapter 11.

Peer target fail System Peer-to-peer communication failed. Extra Message Character: <MODBUS Slave device number>

PID input error Input

Set-up problem. Check the indicated PID configuration parameter.

Extra Message Character: “I” = PID Input parameter value must be a floating-point number “S” = PID Setpoint parameter value must be a floating-point number.


Page 8.10 7955 2540 (Ch08/AC)


Base Alarm Message


Power fail * System The Flow Computer has been without electrical power for a period of time. Examine the date and time stamp of the “ON” and “OFF” messages for the outage period.

Prime BSW limit Limit The prime BSW measurement value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Prover abort

Proving session stopped. Extra Message Character: “I” = Initialisation problem, “I” = Pre-run problem, ”L” = Leak detected “c” = All prove runs completed, “S” = Stream information missing ”s” = Stabilisation not achieved, “p” = Target Plenum pressure is outside alarm limits

Prover in press Limit The pressure at the Prover inlet valve is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit

Prover in temp Limit The temperature measurement value for fluid at the Prover inlet valve is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit

Prover limit Limit

Proving parameter out of limits.

Extra Message Character: “F” = Flow rate, “T” = Temperature, “P” = Pressure, “M” = Meter factor “e” = Proving Error (Missing Pulses), “a” = Prover Archive Full (software fault)

Prover out temp Limit The temperature measurement value for fluid at the Prover outlet valve is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit

Prover out press Limit The pressure at the Prover outlet valve is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit

Prover timeout Limit ‘Displacer’ failed to reach a detector switch within a programmed (SET) time limit. Extra Message Character: “S” = Start sensor, “E” = End sensor

Prt input failed Input

An Analogue Input channel menu data (location) page has a “Fail” status. The Flow Computer is not presently receiving valid signals from a RTD/PRT field transmitter. Check physical connections and monitor the input using the “Health Check” menu. Extra Message Character: “1” = Analogue Input ‘1’, “2” = Analogue Input ‘2’, … , “a” = Analogue Input ‘10’

Prt no cal System Analogue Input not calibrated. Contact the factory for advice. Extra Message Character: “1” = Analogue Input ‘1’, “2” = Analogue Input ‘2’, … , “a” = Analogue Input ‘10’

Pulse out limit Limit The frequency of pulses issued through a Pulse Output has reached the maximum rate. Extra Message Character: “M” = Main Turbine (wired to Pulse Input ‘1’)

Qty batch overrun System Batch has overrun by an amount that has exceeded a ‘programmed (SET) limit.

Qty batch running System

An attempt has been made to start a different type of batch whilst a quantity-based batch is in progress. Extra Message Character: ”T” = Timed batch, “M” = Manual triggered batch

Qty batch start System

Quantity batch could not be started. Extra Message Character: “F” = Flow not halted. There must be no flow before starting Flow Delivery Control, “R” = Quantity batch already running

Retro calc fail System

Retrospective calculation attempted but was unsuccessful Extra Message Character: ”F” = Batch archive empty or record not found, “U” = Update to existing record failed, “W” = Unable to write new record to batch archive

SG limit Limit Specific gravity measurement is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

SpEqu1 calc fail Input Incorrect set-up of Special Equation ‘1’ has caused it to fail.

SpEqu2 calc fail Input Incorrect set-up of Special Equation ‘2’ has caused it to fail.


7955 2540 (Ch08/AC) Page 8.11


Base Alarm Message


StdVol water% lmt Limit % of ‘water’ in oil/water mix (by standard volume) is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Strainer blocked * Input Blockage detected (by Live Input). Check Strainer.

Timeperiod failed Input

A Periodic Time Input channel menu data (location) page has a “Fail” status. The Flow Computer is not presently receiving frequency signals from a transmitter. Check physical connections and monitor the input using the “Health Check” menu.

Extra Message Character: “1” = Time Period Input ‘1’, “2” = Time Period Input ‘2’, etc.

Timeperiod glitch * Input A series of anomalous transmitter readings has occurred. Adjust the setting of the glitch filter parameter that is associated with the Density or Viscosity transducer.

Timeperiod no cal System Periodic Time Input not calibrated. Contact the factory for advice. Extra Message Character: “1” = Time Period Input ‘1’, “2” = Time Period Input ‘2’, etc.

Turb err-dev calc Input An ‘error percentage’ could not be obtained from the linearisation of a calibration curve. Extra Message Character: “M” = Main Turbine (wired to Pulse Input ‘1’)

Turb freq limit Limit A calculated pulse frequency has exceeded the programmed (SET) upper limit Extra Message Character: “M” = Main Turbine (wired to Pulse Input ‘1’)

Turb K-factor err Input A ‘K Factor’ could not be obtained from the linearisation of a calibration curve profile. Extra Message Character: “M” = Main Turbine (wired to Pulse Input ‘1’)

Turb limit failed Limit Missing pulse count has exceeded a programmed (SET) upper limit. Extra Message Character: “1” = Pulse Input ‘1’, “2” = Pulse Input ‘2’, etc.

Turb pcent failed Input The percentage of missing pulses in respect of counted pulses during a cycle has exceeded a programmed (SET) upper limit. Extra Message Character: “1” = Pulse Input ‘1’, “2” = Pulse Input ‘2’, etc.

Turbine no cal System A Pulse (Turbine) Input is not calibrated. Contact the factory for advice. Extra Message Character: “1” = Pulse Input ‘1’, “2” = Pulse Input ‘2’, etc.

Turb visc curve Input A ‘K Factor’ could not be obtained from the linearisation of a calibration curve profile. Extra Message Character: “M” = Main Turbine (wired to Pulse Input ‘1’)

User alarm Limit General user-defined limit alarm. Extra Message Character: “W” = User Alarm ‘W’, “X” = User Alarm ‘X’, etc.

Valve failed Input No response from a valve controller. Extra Message Character: “1” = Valve 1, “2” = Valve 2, etc.

Valve timeout Input No response from a valve controller within expected time limit. Extra Message Character: “1” = Valve 1, “2” = Valve 2, etc.

Visc 4x5 fail Input Metering Kinematic Viscosity by 4x5 matrix referral calculation was unsuccessful. Check all associated configurable parameters using reference pages in Chapter 11.

Visc ASTM fail Input Metering Kinematic Viscosity by ASTM D341 referral calculation was unsuccessful. Check all associated configurable parameters using reference pages in Chapter 11.

Visc dens calc Input

A ‘Viscosity loop’ density measurement channel value has a “Fail” status. Check the physical connections with the Viscosity transducer and configuration parameters. Use the “Health check” facility menu to monitor the associated Time Period Input. Extra Message Character: “A” = Viscosity Loop Density ‘A’, “B” = Viscosity Loop Density ‘B’

Visc density Input The prime ‘Viscosity Loop’ measurement value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit

Visc temp A limit Limit ‘Viscosity loop’ fluid temperature measurement channel ‘A’ value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit

Visc temp B limit Limit ‘Viscosity loop’ fluid temperature measurement channel ‘B’ value is outside a programmed (SET) limit. Extra Message Character: “H” = High limit, “L” = Low limit, “S” = Step limit


Page 8.12 7955 2540 (Ch08/AC)

8.2 Events

8.2.1 Introduction to 7955 events The 7955 keeps a record of important system changes in an Event Log. This is very similar, in concept, to the alarm log, but the nature of the information kept is different.

Event details that can be viewed in the event log:

• Changes to the status of pre-determined† data that affects calculations • Changes to the value of data pre-determined data that affects calculations

Event details that can be seen only in a printout of the event log:

• Messages from hardware diagnostics • Download of a configuration completed

8.2.2 Event indicators Unlike alarms, there are no event indicators on the front panel of the 7955.

8.2.3 How events are received and stored Information about events is stored in two logs:

This gives: • Event Status Display (1) a summary of the contents of the Historical Event Log (2) an indication of the current status of the system.

• Historical Event Log This contains an individual entry for every event stored in the log.

There is enough room, in the historical event log, to store up to 150 event records. When a new event is received, one of two things can happen:

If the event log is NOT full :

A new event record is simply added

If the event log is full : The event configuration data, Event full action, has two options, “Replace” and “Ignore”, for determining how to deal with a new event when the event log is full. (See Table 8.6)

Table 8.6: Event Full Action - Available Options

<Event full action> Option Purpose of Option

Replace Always overwrite the oldest event in the event log Ignore Always discard a new event when the event log is full

Note: The default action is “Replace”

† This can not be changed. The list of auditable data is fixed.


7955 2540 (Ch08/AC) Page 8.13

8.2.4 Examining the Event Summary and the Event Log Press the INFORMATION button If you want to examine the Event Status Display or the Historical Event Log.

• To bring up the Event Status Display, select the Event Summary option. • To bring up the first entry in the Historical Event Log, select the Event History option.

Figure 8.4: How to get to the event log

8.2.5 What the Event Status Display tells you A typical Status Display is shown in the diagram (below). It lists, for each type of event (Auto, User or Periodic) the numbers of alarms which are active and live.

• Active events are events which have been received but not yet accepted. • Live events are events which refer to conditions which are still active.

The number of live events tells you how many of them are still active. If you look at the Historical Event Log this tells you more about these events.

8.2.6 What the entries in the Historical Event Log tell you Figure 8.5 shows the function of the relevant keys, and what is on the display.

Key to figure: 1. Indicates if there are entries BEFORE this one. 2. Location identifier. 3. Type of event. 4. Indicates alarm not accepted. 5. Accept this alarm. 6. Event description. 7. Clear this alarm entry 8. Date and time that this alarm (message) was raised. 9. Indicates that there are alarm entries AFTER this one. 10. Scroll DOWN through the entries. 11. Scroll UP through the alarm entries. 12. Clear all alarm entries.

Figure 8.5: A typical entry in the Historical Event Log


Page 8.14 7955 2540 (Ch08/AC)

Each event has its own entry in the Historical Event Log which tells you:

• Type of event

Type What it means

Auto Changes made by the 7955 application software.

User Changes made by the keypad or done over serial communications.

• Date and time

The date is in the format DD-MM-YY and the time HH:MM:SS. These are entered automatically by the system when the alarm is received. The time is accurate to within one second.

• Acceptance indication

This is only shown for those entries which have not been accepted. When the entry is accepted, the indicator disappears.

• Other entries indication

An up-arrow shows that there are entries before the present one, a down-arrow shows that there are others after. If the entry currently shown is first in the list, there is no up-arrow. If it is last, there is no down-arrow.

• Description of the event

This is an abbreviated description of the event and should be sufficient to help you trace the reason for it.

• Old value and new value

Pressing the RIGHT ARROW key displays another screen with the old and new values of data. Press the LEFT ARROW (or the RIGHT ARROW ) key for the previous display to re-appear.

Figure 8.6: Old value and new value

8.2.7 Clearing all entries in the Historical Event Log To clear all the event entries in the Historical Event log, press the CLR key. This clears all entries in the Historical Event Log and zeroes the entries in the Event Status Display.

Chapter 9 Additional facilities

7955 (Ch09/AC) Page 9.1

9. Additional facilities 9.1 Feature: Archiving 9.1.1 Introduction

The 7955 Flow Computer can perform data logging to generate historical records – archives - of parameter data. The archived data can be retrieved on-demand and displayed within the menu system. It can also be printed out as a report and retrieved by MODBUS (protocol) networked devices.

Values from user-selected parameters can be statistically prepared (e.g. average, maximum, etc.) according to user requirements. Statistical results are recorded at intervals that are defined by the type of data logging. Each logging type has a separate archive with a 20-parameter capacity and the ability to keep statistics from the past.

There are five types of data logging available:

1. Interval

Statistical results are automatically recorded in an “Interval Log” archive at a user-selected time-span. An interval can be as short as a 7955 Flow Computer machine cycle or as long as twelve hours.

A user-selected date and time marks the start of the very first interval.

2. Daily

Statistical results are automatically recorded in a “Daily Log” archive at the same time each day (i.e. 24-hour intervals). A user-selected date and time marks the start of the very first 24-hour period.

3. Manual Statistical results are recorded in a “Manual Log” archive only when triggered manually from the front panel or over serial communications. The beginning of this variable time-span occurs on enabling this type of data logging.

4. Alarm

Statistical results are recorded in an “Alarm Snapshot Log” archive whenever an alarm is raised or is removed. (This is separate from the Alarm History log). The beginning of this variable time-span occurs on enabling this type of data logging.

5. Batch Transaction

Batching data is automatically recorded in a “batch” archive every time a transaction is completed. This type of archiving does not need any configuring apart from adjustments to the archive size. Chapter 18 is dedicated to Batching. Note that the “Statistical information” section (starting on page 9.2) and “configuring details” section (starting on page 9.8) do not apply to batch transaction archiving.

All the types can operate in parallel if required.

The size of an archive is finite but flexible enough to allow re-sizing by hand. Re-sizing actions cause all previously recorded values to be lost forever and should be done prior to data logging commencing. Archives can be selectively viewed on screen and printed out as a report. Printouts of reports can also occur automatically after new statistical results have been archived. Associated parameters (database locations) can be manipulated or retrieved by MODBUS networked device.

Important notice! The two sections that follow should be read and understood before embarking on the configuration task. It is also advisable to try out at least one of the worked examples.


Page 9.2 7955 (CH09/AC)

9.1.2 Statistical Information

The following statistical options are available you…

1. Average

This calculates the average of a parameter value sampled every 7955 Flow Computer machine cycle. The resulting average is ready for whenever it is to be recorded to an archive.

2. Difference

This calculates the difference between the latest sampled parameter value and the result that was last copied to an archive. A result is ready for whenever it is to be recorded to an archive.

3. Maximum

This results in the largest sampled parameter value (since that last archived statistic) being copied to an archive.

4. Minimum

This results in the smallest sampled parameter value (since that last archived statistic) being copied to an archive.

5. None

This results in the very latest sampled parameter value being copied to an archive.

9.1.3 Analysis of an archive This section explains:

• archive space and how it can change • how new statistical data is added to an archive

Archive space and how it changes Each archive has a default amount of memory space in the 7955 Flow Computer. The initial amount is the same for each archive. Dimensions for archive memory space are in terms of depth and width.

• Depth Depth corresponds to the quantity of parameter values that can be kept.

• Width Width corresponds to the total number of bytes required to store a single value from every nominated parameter. (See Table 9.1)

Table 9.1: Bytes Required for all Database Location Types

Width (bytes) Data Type

1 Selection code for an option descriptor in a multiple-choice list

4 A database location without a status attribute (i.e. Set or Free) where the value (e.g. 1.25) is automatically generated by a measurement task. This does not include totals.

5 A data location with a status attribute (i.e. Set or Free) where the value (e.g. 1.25) may be generated by a measurement task.

8 Totals only. For example, Indicated Volume Flow Total

16 Dates and/or times.

21 Text only.

Available memory space for increasing the size of an archive can be viewed by pressing the PRINT MENU key and then selecting the menu: <“Archives”>/<“Re-size archives”>/<“Spare arch. memory”>.

It is very important to carefully plan the set-up of all archive space before data logging commences. Otherwise, be prepared for inevitable data loss when making changes or setting up other archives at a later stage.


7955 (Ch09/AC) Page 9.3

Archive space can be change as follows:

Action Effects on associated archive Extent of data loss

Parameter added to nomination list Width increases. Depth decreases to compensate. Associated archive

Parameter removed from list. Width decreases. Depth increases to compensate. Associated archive

Space increase granted Depth increases. All archives

This is best illustrated in the following sequence of diagrams involving one archive:-

Parameter 1

Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 7

:: :Depth = 8

(1) Archive with an initial depth of 8 anda list with 1 defined parameter:-

The last available record

Parameter 1

Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 5

:: :

Parameter 2

:

Depth = 5

(2) Archive after adding another parameter:-

The last available recordStatistic entry 8

Width=4

Parameter 1 = Line temperature

Width=4 Width=16

Parameter 2 = Time and date

Diagram notes:

(a) Parameters shown here are defined with a data location number. An archive can have a maximumof 20 parameters.

(b) The width value of a parameter is dependent on the type of data location. It is not displayed.

(c) Depth is affected by the total width of parameters. Depth will therefore vary from the example shownhere.

Parameter 1

Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 7

:: :

Parameter 2

: Depth=9

(3) Archive after requesting room to allow 9entries for each parameter.


Parameter 1

Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 8

:: :Depth=9

(4) Archive after removingparameter 2 from list


Statistic entry 8

Statistic entry 9

Statistic entry 9

Width=20 Width=4

Adding new statistics to an archive Several questions can be asked about adding new statistics to an archive… Q1. How are they inserted? Q2. What happens when all records of statistic results are full? The answers to these questions are provided in the exaples that follow.


Page 9.4 7955 (CH09/AC)

(a) Fixed time-span data logging This is described with two sequences of diagrams.

Sequence 1: Archive is not full This shows what will happen when adding statistics to an empty archive. Notice how older statistics are pushed downwards.

T5T0

Parameter 1

14.55Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 6

:: :

Parameter 2

1.0132

:

Parameter 3

(Not used)

:

Newest and oldest statisitic at present

The last possible record for a statisitc in this archive

T1 = 8s T2 = 8s T3 = 8s T4 = 8s

Record:(1)14.55(2)1.0132

Record:(1)14.50(2)1.0133

Record:(1)14.53(2)1.0130

1 secondsamples

Record:(1)?(2)?

(1) Archive state after 8 seconds

Fixed time-span of data logging and archiving Diagram notes:

(a) "Interval" type data logging is shownwith an 8 second time-span.

"Daily" type logging operates in thesame way except T1=24 hours, T2=24hours, etc.

(b) 1 sampled value taken every secondfrom each defined parameter.

(Assume cycle time is 1 second for this).

(c) Parameter 3 is not defined.

(d) Recorded values shown here are notthe result of a specific statisticalcalculation.

(e) T0 is the date and time that this datalogging first began.

(f) Data logging continues beyond T5 untildisabled.

Parameter 1

14.53

14.50

Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 6

:

14.55

: :

Parameter 2

1.0130

1.0133

:

1.0132

Parameter 3

(Not used)

(Not used)

:

(Not used)

Neweststatisitic at

present

Oldest statisticat presentThe last possible

record for a statisitcin this archive



7955 (Ch09/AC) Page 9.5

Sequence 2: Archive is full This shows what will happen when adding statistics to a full archive. Notice how the oldest statistics have to be lost to make space for new statistics.

T9T0T1 = 8s T2 = 8s T3 = 8s T4 = 8s

Record:(1)14.55(2)1.0132

Record:(1)14.50(2)1.0133

Record:(1)14.53(2)1.0130

1 secondsamples

Record:(1)14.51(2)1.0130

Fixed time-span data logging and archiving

T5 = 8s T6 = 8s T7 = 8s T8 = 8s

Record:(1)15.0(2)1.0129

Record:(1)15.1(2)1.0128

Record:(1)15.2(2)1.0127

Record:(1)?(2)?

Parameter 1

15.1

15.0

14.55

Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 6

:

14.51

: :

Parameter 2

1.0128

1.0129

1.0132

:

1.0130

Parameter 3

(Not used)

(Not used)

(Not used)

:

(Not used)

Newest statistic at present

The last possiblerecord for a statisitcin this archive

Parameter 1

15.2

15.1

14.50

Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 6

:

15.0

: :

Parameter 2

1.0127

1.0128

1.0133

:

1.0129

Parameter 3

(Not used)

(Not used)

:

(Not used)

14.55 isnow lost

The last possiblerecord for a statisitc



Diagram notes:

(a) "Interval" type data logging is shownwith an 8 second time-span.







Oldest statisitic at present

1.0132 isnow lost


Page 9.6 7955 (CH09/AC)

(b) Variable time-span data logging

This is described with two sequences of diagrams. Sequence 1: Archive is not full This shows what will happen when adding statistics to an empty archive. Notice how older statistics are pushed downwards.

T4T0

Parameter 1

14.55Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 6

:: :

Parameter 2

1.0132

:

Parameter 3

(Not used)

:

Newest and oldest statisitic at present

The last possible record for a statisitc with this archive

T1 = 8s T2 = 16s T3 = ?s

Record:(1)14.55(2)1.0132

Record:(1)14.50(2)1.0133

1 secondsamples

Record:(1)?(2)?


Variable time-span data logging and archiving Diagram notes:

(a) "Manual" or "Alarm" type data logging isshown here with two completed time-spans. Third time-span is unknown untilan alarm is raised (or cleared) orlogging is next triggered manually by auser.





(e) T0 is when this data logging first began.


Parameter 1

14.50

14.55

Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 6

:: :

Parameter 2

1.0133

1.0132

:

Parameter 3

(Not used)

(Not used)

:

Neweststatisitic at

present

Oldest statisticat presentThe last possible

record for a statisitcin this archive



7955 (Ch09/AC) Page 9.7

Sequence 2: Archive is full This shows what will happen when adding statistics to a full archive. Notice how the oldest statistics have to be lost to make space for new statistics.

T9T0T1 = 6s T2= 7s T3 = 9s T4 =

5s

Record:(1)14.55(2)1.0132

Record:(1)14.50(2)1.0133

Record:(1)14.53(2)1.0130

1 secondsamples

Record:(1)14.51(2)1.0130

Variable time-span data logging and archiving

T5 = 8s T6 = 12s T7 = 8s T8 = ?s

Record:(1)15.0(2)1.0129

Record:(1)15.1(2)1.0128

Record:(1)15.2(2)1.0127

Record:(1)?(2)?

Parameter 1

15.1

15.0

14.55

Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 6

:

14.51

: :

Parameter 2

1.0128

1.0129

1.0132

:

1.0130

Parameter 3

(Not used)

(Not used)

(Not used)

:

(Not used)

Newest statisitic at present


Parameter 1

15.2

15.1

14.50

Statistic entry 1

Statistic entry 3

Statistic entry 2

Statistic entry 6

:

15.0

: :

Parameter 2

1.0127

1.0128

1.0133

:

1.0129

Parameter 3

(Not used)

(Not used)

(Not used)

:

(Not used)

14.55 isnow lost



Diagram notes:

(a) "Alarm" and "Manual" type data loggingare both represented with multiplevariable time-spans.






(f) Data logging to archive continuesbeyond T9 until disabled.

Oldest statisitic at present

1.0132 isnow lost



Page 9.8 7955 (CH09/AC)

9.1.4 Configuration details Use the following table to find the instructions for configuring an archiving activity. It is advisable to try out an example before embarking on the configuration task.

Configuration task 1st. Page

• Interval Archiving 9.9

• Daily Archiving 9.10

• Manual Archiving 9.10

• Alarm (snapshot) Archiving 9.12

• Re-sizing of archives 9.13

Note: Batch archiving does not require any configuring because it is automatically ready for any transactions

that take place. Only re-sizing of the archive needs to considered, as guided in Section 9.1.3.


7955 (Ch09/AC) Page 9.9

Configuration task: “Interval logging” Objectives: (i) Set-up a parameter list, (ii) ‘Set’ a start date/time, (iii) ‘Set’ a fixed interval and (iv) enable this data logging type. Instructions: 1. Before proceeding, ensure that you have a list of parameters and their database location IDs 1. The

identification numbers are important because they will be input to identify parameters to be archived.

2. Press the PRINT-MENU key

3. Navigate to this menu: <“Archives”>/<“Configure logs”>/<“Interval log”>

4. Nominate the parameters to be archived

(a) Browse through the “Configure list” sub-menu to locate the ‘pointer’ and ‘action’ menu data pages.

(b) Starting with the first entry, program in a location ID and then select a statistical (action) function. (See Table 9.2 for further guidance)

(c) Repeat (4b) with the next entry until all parameters have been nominated.

5. Work through the remaining configuration parameters as guided in Table 9.3.

Table 9.2: First Entry Configuration Parameters

Menu Data * (as displayed) Purpose

Int list loc 1 • Nominate ‘parameter 1’ with a database location ID

Int list action 1 • Choose a statistical/non-statistical function to be applied to all values sampled from ‘parameter 1’. (Page 9.2 has a summary of the various supported functions)

* Abbreviations: “Int” = Interval, “loc” = location

Table 9.3: Configuration Parameter Checklist of Interval Archiving

Menu Data * (as displayed) Purpose

Interval start time • ‘Set’ the date and time for start of the first interval period.

Interval time • Select the interval frequency.

Interval log/print • Options: (1) “Disabled” – deactivate data logging type / already deactivated (2) “Log data only” - activate data logging type but do not print-out a report after archiving (3) “Log and print data” – activate data logging type and print-out a report after archiving *

* Requires a serial port to be configured for connection to a printer or terminal. For further information, refer to Chapter 7

Interval Archiving Notes:

1. The interval type of data logging operates independently of the other types.

2. Intervals are always synchronised to the 7955 Flow Computer calendar clock. For example, a 10-second interval will first occur on the minute rollover and then re-occur every multiple of 10 seconds. An interval start time that is not divisible by the interval will effectively be delayed to the next multiple of the interval.

3. Some or all values could be lost if a power failure occurs while they are being logged. The data logging will re-synchronise to the calendar clock after the re-start.

1 The location identification of a parameter can be seen on-screen by navigating the menu data page and then pressing the ‘a’-key.


Page 9.10 7955 (CH09/AC)

Configuration task: “Daily” logging details Objectives:

(i) Set-up a parameter list, (ii) ‘Set’ a start date/time and (iii) enable this data logging type Instructions: 1. Before proceeding, ensure that you have a list of parameters and their database location IDs 2. The



3. Navigate to this menu: <“Archives”>/<“Configure logs”>/<“Daily log”>


(4a) Browse through the “Configure list” sub-menu to locate the ‘pointer’ and ‘action’ menu data pages.

(4b) Starting with the first entry, program in a location ID and then select a statistical (action) function. (See Table 9.4 for further guidance)

(4c) Repeat step 4b with the next available list entry until all parameters have been nominated.


Table 9.4: Daily Archive - Configuration Parameters for First Entry of List

Menu Data * (as displayed) Purpose of Parameter

Daily list loc 1 • Nominate ‘parameter 1’ with a database location ID

Daily list action 1 • Choose a statistical/non-statistical function to be applied to all values sampled from ‘parameter 1’. (Page 9.2 has a summary of the various supported functions)

* Abbreviations: “Loc” = Location

Table 9.5: Daily Archive Configuration Parameters


Daily start time • ‘Set’ the date and time for commencement of the first 24 hour period

Daily report • Options: (3) “Disabled” – deactivate data logging type / already deactivated (4) “Log data only” - activate data logging type but do not print-out a report after archiving (3) “Log and print data” – activate data logging type and print-out a report after archiving *


Daily Archive Notes:

A Daily type data logging can operate independently of the others.

B A period that falls within an adjustment for daylight saving will be 24 +/- 1 hour.

C Some or all values could be lost if a power failure occurs while they are being logged. The data logging will re-synchronise to the calendar clock after the re-start.

Configuration task: “Manual” logging details

2 The identification number of a parameter can be seen on-screen by navigating to the menu data page and then pressing the ‘a’-key.


7955 (Ch09/AC) Page 9.11

Objectives: (i) Set-up a parameter list and (ii) enable this data logging type Instructions: 1. Before proceeding, ensure that you have a list of parameters and their database location IDs 3. The



3. Navigate to this menu: <“Archives”>/<“Configure logs”>/<“Manual log”>






Table 9.6: Manual Trigger Archive - Configuration Parameters for First Entry of List


Manual snap loc 1 • Nominate ‘parameter 1’ with a database location ID

Manual snap act 1 • Choose a statistical/non-statistical function to be applied to all values sampled from ‘parameter 1’. (Page 9.2 has a summary of the various supported functions)

* Abbreviations: “snap” = snapshot, “loc” = location, “act” = action

Table 9.7: Manual Trigger Archive Configuration Parameters


Manual log/print • Options: (1) “Disabled” – deactivate data logging type / already deactivated (2) “Log data only” - activate data logging type but do not print-out a report after archiving (3) “Log and print data” – activate data logging type and print-out a report after archiving *


Manual Trigger Archive Notes:

A The trigger for manual type data logging is activated by selecting a soft-command at the menu data page with “Trigger manual log” as the parameter label. It is found under: <“Archives”>/<“Trigger manual log”>.

B Manual type data logging operates independently of the others.

C Some or all values could be lost if a power failure occurs while they are being logged. The data logging will re-synchronise to the calendar clock after the re-start.



Page 9.12 7955 (CH09/AC)

Configuration task: “Alarm” (snapshot) logging details

Objectives: (i) Set-up a parameter list and (ii) enable this data logging type Instructions: 1. Before proceeding, ensure that you have a list of parameters and their database location IDs 4. The



3. Navigate to this menu: <“Archives”>/<“Configure logs”>/<“Manual log”>






Table 9.8: Alarm Triggered Archive - Configuration Parameters for First Entry of List


Alarm snap loc 1 • Nominate ‘parameter 1’ with a database location ID

Alarm snap action 1 • Choose a statistical/non-statistical function to be applied to all values sampled from ‘parameter 1’. (Page 9.2 has a summary of the various supported functions)

* Abbreviations: “snap” = snapshot, “loc” = location

Table 9.9: Alarm Triggered Archive Configuration Parameters


Log/print on alarm • Options: (1) “Disabled” – deactivate data logging type / already deactivated (2) “Log data only” - activate data logging type but do not print-out a report after archiving (3) “Log and print data” – activate data logging type and print-out a report after archiving *


Alarm-Trigger Archive Notes:

A Alarm type data logging can operate independently of the others.

B Some or all values could be lost if a power failure occurs while they are being logged. The data logging will re-synchronise to the calendar clock after the re-start.



7955 (Ch09/AC) Page 9.13

9.1.5 Re-sizing Archive Space

Important notices!

1. Adding a parameter to a data logging list causes all recorded statistics to be immediately lost from the associated target archive. Other archives are not affected by this.

2. Removing a parameter from a data logging list causes all recorded data to be immediately

lost from the associated target archive. Other archives are not affected by this. 3. Increasing or decreasing space will result in all recorded data being lost from all archives.

Re-size Instructions: 1. Press the PRINT-MENU key

2. Navigate to this menu: <“Archives”>/<“Re-size archives”>

3. Check how much spare archive memory is available

Note: If the spare archive memory is reported as 0 bytes and archiving has not been in use, format the archives and then re-check the reported value

4. Re-size archives according to your requirements

• The following are ‘re-size’ menus:-

(1) “Alarm log” – Alarm Trigger Archive re-sizing (2) “Manual log” – Manual Trigger Archive re-sizing

(3) “Daily log” – Daily Archive resizing

(4) “Interval log” – Interval Archive resizing

(5) “Transactions log” – Batch Archive re-sizing

Each ‘re-size’ menu features two menu data pages. One menu data page is for requesting an increase or decrease to the depth – i.e. the maximum number of values per parameter that can be presently stored in the associated archive. The other menu data page shows the maximum number allowed at present.

To request more space for an archive…

(4a) ‘Set’ a new value in the appropriate ‘request’ parameter

(4b) Confirm the request for more space by selecting the "Format” soft-command (option descriptor) through the menu data page with “Format all archives”.

Warning! Increasing or decreasing space will cause all recorded values to be lost from all archives. Use the ‘max snaphot’ menu data page to check on the result of a request.


Page 9.14 7955 (CH09/AC)

9.1.6 Operation details (Reporting) Operations involve selective viewing and printing out of the archives.

Viewing Archives Recorded values can be viewed on the 7955 Flow Computer display. No configuration is required for this feature. Follow the self-contained instructions that are provided below.

How to view the Interval Archive 1. Navigate to this menu: <“Archives”>/<”View / print logs”>/<”Interval trig log”>

2. Find out if data has been recorded in the archive by selecting the “Num snaps stored” menu option. The menu data page shows how many values (per parameter) are available from previous elapsed intervals.

3. There are menu data pages (database locations) for displaying a previously recorded value for every listed (nominated) parameter. For example, the value of the first nominated parameter is found in the “Intvl snap value 1” menu data location.

By default, the most recently recorded values from the last interval can be seen. The “Select snapshot” menu option is for selecting another elapsed interval. For example, snapshot ‘1’ is for showing the oldest interval of recorded values. Selecting a ‘snapshot’ that does not yet exist will always cause all the most recent recorded values to be selected and then displayed.

4. The date and time, of when the presently displayed statistics were recorded, can be seen by selecting “View snapshot time” option.

How to view the Daily Archive 1. Navigate to this menu: <“Archives”>/<”View / print logs”>/<”Daily log”>

2. Find out if data has been recorded in the archive by selecting the “Num snaps stored” menu option. The menu data page shows how many values (per parameter) are available from previous 24-hour periods.

3. There are menu data pages (database locations) for displaying a previously recorded value for every listed (nominated) parameter. For example, the value of the first nominated parameter is found in the “Daily snap value 1” menu data page.

By default, only the most recently recorded values from the previous 24-hour period can be seen. Use the “Select snapshot” menu option to select another 24 hour period. For example, snapshot ‘1’ is for showing the very first 24-hour period of recorded values. Selecting a snapshot (i.e. 24-hour period) that does not yet exist will always cause all the most recent recorded values to be selected and then displayed.

4. The date and time, of when the presently displayed statistics were recorded, can be seen by selecting “View snapshot time” option.

How to view the Manual Trigger Archive 1. Navigate to this menu: <“Archives”>/<”View / print logs”>/<”Manual log”>

2. Find out if data has been recorded in the archive by selecting the “Num snaps stored” menu option. The menu data page shows how many recorded values (per parameter) are available.

3. There are menu areas for viewing previously recorded values for each listed parameter. Look for the numerous “Snap item value” sub-menus. By default, only the most recently recorded values from the last trigger can be seen. Use the “Select snapshot” menu option to select and display recorded values from previous triggers. For example, edit a value of 1 to retrieve the oldest snapshot. Selecting a snapshot that does not yet exist will cause all of the most recent recorded statistics to be re-displayed.

4. The date and time, of when the presently displayed statistics were recorded, can be seen by selecting “View snapshot time” menu option.


7955 (Ch09/AC) Page 9.15

How to view the Alarm Trigger Archive 1. Navigate to this menu: <“Archives”>/<“View / print logs”>/<“Alarm log”>

2. Find out if data has been recorded in the archive by selecting the “Num snaps stored” menu option. The menu data page shows how many recorded values (per parameter) are available.

3. There are a number of menu data pages for viewing previously recorded values for all listed parameters. Look for the numerous “Snap item value” sub-menus.

By default, only the recorded values since the last alarm can be seen. The “Select snapshot” menu option is for selecting and displaying recorded values from previous new alarm occurrences. For example, editing a value of ‘1’ will select the oldest set of values. Selecting a snapshot that does not yet exist will always cause the most recent recorded values to be selected and then displayed.

4. The date and time, of when the presently displayed values were recorded, can be seen by selecting “View snapshot time” option.

How to view the Batch Archive 1. Navigate to this menu: <“Archives”>/<“View / print logs”>/<“Transaction log”>

2. Find out if data has been recorded in the archive by selecting the <“Num snaps stored”> menu option. The menu data page shows how many batch transactions were recorded.

3. There are a number of menu data pages for viewing previously recorded values for all listed parameters. Look for the numerous “Snap item value” sub-menus.

By default, recorded values since the last alarm can be seen. The “Select snapshot” menu option is for selecting and displaying recorded values from previous batch transactions. For example, editing a value of ‘1’ will select the oldest set of values. Selecting a snapshot that does not yet exist will always cause the most recent recorded statistics to be selected and then displayed

Printing Archives (through a configured serial port)

Archives can printed-out in several ways:

1. Method: On-demand (1a) From outside the <“Archives”> menu

This feature requires no configuration. To activate, press the PRINT-MENU soft-key and then select the “Print report” menu option. Now choose a report by selecting from the multiple-choice of options.

Option (as displayed) Purpose of option

Interval log • Printout the ‘Interval’ archive as a report.

Daily log • Printout the ‘Daily’ archive as a report.

Manual log • Printout ‘Manual’ archive as a report.

Alarm log • Printout ‘Alarm’ (Snapshot) archive as a report.

(1b) From inside the <“Archives”> menu

This feature requires no configuration. To activate, press the PRINT-MENU soft-key and then the follow instructions.

Instructions: 1. Navigate to this menu: <“Archives”>/<“View / print logs”>

2. Select a menu that is name-associated with the archive 3. Select the “Print snapshot” menu option 4. Select the “Print” soft-command option (value)


Page 9.16 7955 (CH09/AC)

2. Method: Automatic Printed Report Archiving can be configured to automatically printout a report whenever data is archived.

Interval archive instructions:

1. Navigate to this menu: <“Archives”>/<“Configure logs”>/<“Interval log”>/<”Enable”> 2. Select the “Log and print data” option

Daily archive instructions:

1. Navigate to this menu: <“Archives”>/<“Configure logs”>/<“Daily log”>/<”Enable”> 2. Select the “Log and print data” option

Manual archive instructions:

1. Navigate to this menu: <“Archives”>/<“Configure logs”>/<“Manual log”>/<”Enable”> 2. Select the “Log and print data” option

Alarm archive instructions:

1. Navigate to this menu: <“Archives”>/<“Configure logs”>/<“Alarm log”>/<”Enable”> 2. Select the “Log and print data” option

Batch archive instructions:

1. Navigate to this menu: <“Archives”>/<“Configure logs”>/<“Transaction log”>/<”Enable”> 2. Select the “Log and print data” option

All methods require a Serial Communications Port to be set-up for printing. Printouts are transmitted through the serial port that is configured exclusively for connection to a printer.


7955 (Ch09/AC) Page 9.17

9.1.7 GUIDED EXAMPLES OF ARCHIVING

Guided Example 1 Objective: (i) Set-up 7955 Flow Computer to record the average of line pressure measurements on a daily basis

This guided example involves configuring the “Daily log” archive to record (snapshot) the average of all pressure readings during a 24-hour period. It is assumed that the measurement task is already set-up.

Instructions:

1. Add the parameter to the “Daily log” archive list

(1a) Press the PRINT-MENU soft-key

(1b) Navigate to this menu: <“Archives”>/<“Configure logs”>/<“Daily log”>/<“Configure list”>/<“Entry 1”>

(1c) Select the “Pointer” menu option – this displays a menu data page with “Daily list loc 1”

(1d) Press the ‘b’ soft-key and then type in the database location ID for the pressure parameter

(1e) Confirm the edited location ID by pressing the ENTER soft-key

(1f) Select the <“Action”> menu and then change the menu data page option selection to “Averaging”

2. ‘Set’ an initial date and time

(2a) Navigate to this menu: <“Archives”>/<“Configure logs”>/<“Daily log”>/<“start time”> (2b) Press the ‘b’ soft-key and then edit a date and time for the commencement of the first 24-hour period

Notes: • The 7955 date and time is displayed within menu system. Look inside this menu: <”Time”> • A date of ‘zero’ is the same as specifying the present calendar date. • A time of ‘zero’ is the same as specifying the present time.

3. Activate the data logging activity

(3a) Select menu: <“Archives”>/<“Configure logs”>/<“Daily log”>/<“Enable / Disable”> (3b) Choose an option as guided in the table

Option

(as displayed) Purpose of option

Log data only • Data copied into the “Daily log” archive. No printed report following archive

Log and print data • Data copied into the “Daily log” archive. Print a report following archive. *

* A serial port should be configured for connection to a ‘printer’

4. Check on the data logging after 24 hours

Results are best viewed on a connected printer or a PC running a terminal emulation program. Alternatively, results can be viewed within the menu system.

(4a) Select the menu: <“Archives”>/<“View / print logs”>/<“Daily log”>

(4b) Select various menu data pages…

Menu Data Page (as displayed) Purpose

Num daily snapshots • The number of snapshots per parameter inside the “Daily log” archive.

Daily snap, 0=latest • View selection: 0 = recent snap, 1 = oldest snap, 2 = 2nd oldest snap, etc.

Daily snap value 1 • Selected view of a value from the parameter listed under “Entry 1”.

Daily snapshot time • Shows the date and time of the last daily snapshot.


Page 9.18 7955 (CH09/AC)

9.2 Feature: PID Control Proportional-Integral-Derivative (PID) is a control algorithm for efficiently attaining and then maintaining a LIVE measurement parameter at a user-supplied target (or ‘set-point’) value. PID control is available for controlling one measurement parameter.

WARNING! EXPERT KNOWLEDGE OF PID IS ESSENTIAL TO MAKE USE OF THIS FEATURE

9.2.1 Overview Closed-loop PID Control The implemented PID algorithm will continuously check on the difference between a target (‘set-point’) measurement value and the latest LIVE value of a nominated measurement. Whenever the difference is unacceptable, an adjustment – to narrow the difference - is derived from a three-term equation, as seen below.

A calculated adjustment value – or PID output value - is checked against any enabled safeguards before being made available in a database location. Once the PID output value is freely available, it can be transmitted to an external system through any analogue output. That action should result a process change to narrow the difference. This routine is repeated every cycle until the difference is within acceptable limits.

( ) ( ) ( ) ( ) ( )( )m i K e i T K e k KT

e i e ic id

k

i

= + + ⎛⎝⎜

⎞⎠⎟

− −⎛

⎝

⎜⎜

⎞

⎠

⎟⎟

=∑* * * 1

0

ProportionalTerm

IntegralTerm

DeriviativeTerm

Where:

( )m i = Control output (for steering measurement towards a set-point)

{Menu Data: <“PID Output”>}

Kc = Proportional gain factor

{Menu Data: <“PID Gain”>}

Ki = Integral time constant (‘Reset’ rate)

{Menu Data: <“PID Integral act”>}

Kd = Derivative time constant

{Menu Data: <“PID Derivative act”>}

( )e i = Difference between set-point and measurement (i.e. the ‘error’) at cycle i {No Menu Data Page}

( )e i −1 = Difference between set-point and measurement (i.e. the ‘error’) from previous cycle

{No Menu Data Page}

( )e k = The error over k cycles for 0 ≤ k ≤ i {No Menu Data Page}

T = Elapsed time since measurement value last sampled for PID algorithm

{No Menu Data Page}

Notes:

(1) Variables cK , iK and dK can be edited through pages within the 7955 menu system.

(2) In practice, the first order difference term, (e(i) - e(i-1)), is very susceptible to noise problems. In most practical systems this term is replaced by the more stable, higher order equation: Δe = ( e(i) + 3*e(i-1) - 3*e(i-2) - e(i-3) ) / 6


7955 (Ch09/AC) Page 9.19

Open-loop PID Control With this method, the aim is for the PID output value itself to be driven towards a user-supplied target (set-point) output value. The measurement ‘set-point’ has no purpose. Whenever there is a calculated difference, an adjustment – to narrow the difference - is derived from the three-term equation seen earlier. However, the calculated ‘error’ terms are based on the difference between the “LIVE” PID output value and a “SET” target (user) PID output value. The calculated adjustment value – PID output value - is checked against two safeguards before being made available in a database location. Once the PID output value is freely available, it can be transmitted to an external system through any analogue output. That action should result a process change to gradually narrow the difference. This routine is repeated every cycle until the difference is within acceptable limits.

9.2.2 Configuration details Instructions: 1. Set-up the “LIVE” measurement that is to be controlled

• All the configuration reference pages for measurements are located in Chapter 11.

• Ensure that the location identification number 5 of the measurement (to be controlled) is noted

2. Set-up PID control

• Review the schematic (Figure 9.1) in conjunction with the associated parameters (Table 9.10)

• Navigate to this menu: <”Configure”>/<”PID Control”> and then work through all the associated parameters, setting values and selecting options as necessary.

• Check on the idle system time to see if the cycle time needs to be increased. [MENU: <”Time”>] 3. Configure a live analogue output to transmit a PID output value

During every machine cycle, the analogue output will need to transmit a PID output value to whatever external system can initiate a process change (e.g. a valve controller increasing flow).

The PID output value is either:

• an adjustment for the “LIVE” measurement to reach a target (set-point) measurement value or

• an adjustment for the PID output value itself to reach a target (set-point) value, also indirectly affecting the “LIVE” measurement. [Note: The measurement set-point is not used in this case]

A guide to the analogue output parameters and settings is listed in Table 9.11 (on page 9.20)

Figure 9.1: PID Control - Schematic of Blocks and Parameters

Calculate'Error'

3

PIDAlgorithm

5 6 7SETPOINT

(for measurement)

"LIVE" MEASUREMENT

4

ARWLimit

Check8 9

10 11

CheckRamp Limit

13 14

16

PIDOutput

"LIVE"AdjustmentValue (%)

mA Output15OR12

SETPOINT(for PID output)

Status checkdecides the

set-point used

PIDOutput

12

5 This number can be found by examining the ‘.man’ text file that is present on the media of our FC-Config PC tool. The ‘.man’ file is

unique for every software release. Contact us if you require a copy of the file and/or FC-Config. Alternatively, locate the data page within the menu system and then use the ‘a’-key to toggle the display of the number on or off.


Page 9.20 7955 (CH09/AC)

Table 9.10: PID Control Parameters

Index Menu Data (as displayed) Default Setting Notes?

- PID Enable “Disable”

1 PID Setpoint ptr (“PID Setpoint”) A

2 PID Setpoint 0.0 (A)

3 PID Input ptr 0000 (“Off”) B

4 PID Error type “Single error” C

5 PID Gain 0.0

6 PID Integral act 0.0

7 PID Deriviative act 0.0

8 PID Range max 0.0

9 PID Range min 0.0

10 PID ARW “Disable” D

11 PID ARW HI limit 0.0 (%) (D)

12 PID ARW LO limit 0.0 (%) (D)

13 PID Ramp limit “Ramp limit off” E

14 PID Ramp Gradient 5.0 (%) (E)

15 PID Output * 0.0 F:1, G

16 PID User Output * 0.0 F:2, G

* shows data that can be “Live” or “Set”

Table 9.11: Analogue Output '1' Parameters (Guide for PID Control Set-up)


Example Value or Option Setting Comments

mA output 1 ptr list “User” • Essential option

mA 1 param val @100% (<”PID Range max”> Value) • See Table 9.10

mA 1 param val @0% (<”PID Range min”> Value) • See Table 9.10

mA output 1 type (4-20mA or 0-20mA) • Select suitable mA range

mA output 1 source (<”PID Output”>) • ID for <”PID Output”>

mA output 1 value * (LIVE Value) • Values from <”PID Output”>

Analogue Output ‘1’ has been used here as a guide to setting-up

Notes: (for Table 9.10)

A By default, this configuration parameter is usually programmed with the database location ID of the parameter <“PID Setpoint”>. However, any database location with a floating-point value could be identified - programmed in - as the parameter supplying the set-point (target) value.

An input alarm is raised if the ‘value’ of the identified ‘set-point’ parameter is not a floating-point value. PID control is then temporarily deactivated until the alarm is clearable when a more suitable parameter is identified.

B This configuration parameter must be programmed with the database location ID of the measurement

parameter that is to be controlled. It must be a parameter with a floating-point value.

An input alarm is raised if the ‘value’ attribute of the measurement parameter is not a floating-point data type. PID is then temporarily deactivated until the alarm is clearable when a suitable parameter is identified.


7955 (Ch09/AC) Page 9.21

(Notes continued…) C The “Simple Error” option will calculate the ‘error’ as simply the difference between the setpoint value and the

measurement value. However, the “Complex Error” option will provide a more stable ‘error’ value. The error is derived from the following expression: Δe = (e(i) + 3*e(i-1) - 3*e(i-2) - e(i-3) ) / 6

D Safeguard feature. See Section 9.2.4 on page 9.21.

E Safeguard feature. See Section 9.2.3 on page 9.21.

F:1 For the closed-loop method you must change the status of <”PID Output”> and <”PID User Output”> to both be

“Live”. Calculated adjustment values will then be displayed by both parameters.

F:2 For the open-loop method you need to SET a value for the <”PID User Output”> parameter. The status of the <”PID Output”> parameter must be “LIVE”.

G Set-up any analogue output to transmit a value of the <”PID Output”> parameter. This database location ID is

1288. Configure the analogue output to utilise the ‘user parameter’ option. Refer to Chapter 11 for applicable configuration reference pages. Analogue output connections are as guided in Chapter 2.

9.2.3 Ramp-limit Safeguard Many systems implement a limiter on the maximum rate of change to the PID output value. This has a similar effect to an engine rev-limiting device. However, this PID safeguard prevents physical devices from being damaged through unnecessary adjustments.

The ramp-limit is specified in degrees, representing the angle the output makes with the horizontal on a graph. The time axis resolution is therefore critical to the significance of this parameter. A limit of zero degrees would make output ramping impossible and a limit of 90 degrees or greater would allow maximum ramping.

With the open-loop PID control method, the ramp-limit checks are mandatory and are applied every cycle. However, programming a zero degree angle will inhibit this safeguard.

Figure 9.2: Ramp-Limit safeguard illustration

PID

Oup

ut (%

)

X1

Y

X2Y

Ramp LimitGradient

PID Output(Tangent)

Xn

PID Output(Angle)

Y

Ramp Limit(Angle)

X2< Y

X1< Y Time

9.2.4 Anti-Reset-Windup Safeguard Practical systems stop the summation of error terms if the PID output value is outside a user-specified boundary. This limiting of the error summation is commonly referred to as Anti-reset-windup (ARW).

When ARW is enabled, ARW limiting is applied to every output value from the PID calculation before it is saved in the 7955 database. The ARW limit boundary is specified as a low and high percentage of the full-scale (maximum) PID output value.

With the open-loop PID control method, the ARW boundary checks are mandatory and are applied every cycle. However, a zero percent boundary will inhibit ARW limiting.

Figure 9.3 demonstrates ARW in action, complemented with example settings as shown in Table 9.12.


Page 9.22 7955 (CH09/AC)

Figure 9.3: Anti-reset-windup (ARW) in action

HIGH

LOW

AR

W B

ound

ary

TIME

PID

OU

TPU

T (%

)

0

100

Process change(e.g. Pump failure)

ARW is limiting output %(e.g. minimum flow)

Process change(e.g. pump fixed)

ARW is limiting output %(e.g. maximum flow)

HIGH

LOW

AR

W B

oundary

5

90

PID OUTPUT varyingas process changes

Table 9.12: ARW Associated Parameters

Menu Data ** (as displayed) Example Setting Comment

PID Range max 100.0 • The maximum – full-scale - PID output value

PID Range min 0.0 • The minimum allowed PID output value

PID ARW “Enable” • Activate ARW boundary checking

PID ARW HI limit 100.0 (%) • % of <PID max range> for upper ARW boundary

PID ARW LO limit 0.0 (%) • % of <PID max range> for lower ARW boundary

PID Output * (“Live” Value) • “LIVE” Adjustment value (%) for the mA output

* shows data that can be “Live” or “Set”

** Parameters are located within this menu: <”Configure”>/<”PID control”>


7955 (Ch09/AC) Page 9.23

9.3 Selecting units and data formats You can select the units which it displays the data, as well as the formats in which the data is displayed.

You can choose the units and formats for:

• Volume flow rate

• Volume flow total

• Standard volume flow rate

• Standard volume flow total

• Mass flow rate

• Mass flow total

• Density

• Temperature

• Pressure

• ‘K’ factor

• Time period

• Kinematic viscosity

• Base kinematic viscosity

• Dynamic viscosity

A full list of the units (metric and imperial) is given at the end of this chapter. Note that, if you change the units, the values are converted automatically to reflect the change.

9.4 Parameter Alarm Limits You can set limits for some parameters so that an alarm is generated if the limits are exceeded.

There are four types of limit:

• High limit: The highest value that the parameter can have before an alarm is generated.

• Low limit: The lowest value that the parameter can have before an alarm is generated.

• Step limit: The greatest allowable step between successive values before an alarm is generated.

• Comparison limit: The greatest allowable step between values from two or more channels without an alarm

The parameters, and the types of limit that you can set for them, are:

• Mass flow rate: high and low • Gross volume flow rate: high and low • Net volume flow rate: high and low • Sediment and Water high and low • Meter density: high, low and step • Density ‘A’ & ‘B’ Comparison • Base density high and low • Meter temperature: high and low • Meter pressure: high and low • Prover Inlet temperature high and low • Prover outlet pressure high and low • Prover Inlet pressure high and low • Prover outlet temperature high and low • Alarm X and Y: high and low. • Alarm ‘A’ and ‘B’ Comparison • Indic. Std. volume flow rate: high and low • Gross Std. volume flow rate: high and low • Turbine frequency high • Dynamic viscosity High, low and comparison • Kinematic viscosity High and low


Page 9.24 7955 (CH09/AC)

9.5 Fallback values and modes A fallback value is used as a temporary substitute for a parameter if a live input (i.e., the transducer, transmitter or wiring), which is normally used to calculate the parameter, should fail.

A fallback must have one of the following modes:

• None The system uses whatever value is available for the parameter regardless of whether or not the live input has failed.

• Last good value The system uses, for the parameter, the last value prior to failure.

• Fixed value The system uses whatever fixed value you have specified for the fallback.

You can set fallback values for:

• Metering density

• Base density

• Metering temperature

• Prover inlet temperature

• Prover outlet temperature

• Prover inlet pressure

• Prover outlet pressure

• Metering pressure

• Densitometer pressure

• Sediment & Water percentage

9.6 Units which the 7955 can display The 7955 can display data values with many different units of measurement, as listed in Table 9.13 on page 9.25. However, when communicating with other devices, the data is always sent using the base units.

In Table 9.13, the following definitions are used:

• Base units • The 7955 transmits all data in base units (when using a MODBUS link). • Data values in the 7955 database are stored in base units for calculations.

• Default units: • Units which the 7955 displays unless you choose an alternative.

• Other units: • Units which you can choose instead of the default.

Note that many of the abbreviations used in the tables are defined in the glossary.


7955 (Ch09/AC) Page 9.25

Table 9.13: Supported units of measurement

Parameter Category

Base units (Comms. &

Calculations) Default units (on-screen)

Other units available for on-screen (as displayed)

Temperature Deg. C Deg. C Deg. F Kelvin Ohms

Pressure bar abs bar abs Pa abs psia kPa guage kg/cm2

KPa abs bar guage MPa guage

MPa abs Pa guage psig

Volume m3 m3 m3 x E3 m3 x E6 in3

ft3 100ft3 MM ft3

barrel gallon (UK) gallon (US)

cc litres

Standard Volume

Std m3 Std m3 Std m3 x E3 Std ft3 Std barrel Norm cc Norm m3 x E3 Norm ft3 Norm barrel Std cc

Std m3 x E6 Std 100ft3 Std gallon (UK) Norm litres Norm m3 x E6 Norm 100ft3 Norm gallon (UK) Std litres

Std. in3 Std MM ft3 Std gallon (US) Norm m3 Norm in3 Norm MM ft3 Norm gallon (US)

Mass (Total) kg kg tonne oz g

ktonne lb

Mtonne ton

Density kg/m3 kg/m3 tonnes/m3 oz/in3 oz/ft3

oz/barrel oz/gallon (UK) oz/gallon (US)

lb/in3 lb/ft3 lb/barrel

lb/gallon (UK) lb/gallon (US) tons/ft3

tons/barrel tons/gallon(UK) tons/gallon (US)

g/cc g/litre g/m3

kg/cc kg/litre kg/cm2

Base density kg/m3 kg/m3 As for density

Time s (seconds) s (seconds) min us

hour ms

day

Frequency Hz Hz kHz pulse m/s

pulse/ns pulse/s

pulse u/s pulse/min

‘K’ Factor pulse/m3 pulses/m3 pulse/in3 litre/pulse ft3/pulse

pulse/ft3 m3/pulse pulse/cc

cc/pulse in3/pulse pulse/litre

Dynamic Viscosity

cP cP Pa.s Reyn

kgf.s/m2 slug/fts

P lbf.s/ft2

Kinematic Viscosity

cSt cSt mm2/s ft2/s

cm2/s

m2/s

Base Kinematic Viscosity

cSt cSt mm2/s in2/s

cm2/s ft2/s

m2/s

Mass rate kg/hour kg/hour Mass units / time units

Volume rate m3/hour m3/hour Volume units / time units

Standard volume rate

m3/hour m3/hour Volume units / time units


Page 9.26 7955 (CH09/AC)

Chapter 10 Configuring by using Wizards

7955 2540 (CH10/AC) Page 10.1

10. Configuring using Wizards

10.1 Introduction to Wizards We recommend that you use software Wizards to configure the 7955 Flow Computer for your installation. Wizards are easy to use facilities that will take a user through all the data locations and decisions that are required to satisfy the requirements of a measurement task.

There are individual wizards available for each measurement task. For example there is a “Pressure” wizard for configuring line pressure and atmospheric pressure.

To fully configure a 7955 Flow Computer, it is very likely that several measurement tasks are required and, therefore, several wizards will need to be used. It is often more efficient to use a “full set-up” wizard. This wizard can guide users through setting up more than measurement task.

Section 10.3 has a “Quick-view” guide (table) for finding out what wizards are available and what can be achieved with them.

Section 10.4 features a special wizard for selecting a standard for units of measurement.

10.2 Using Wizards Although wizards are easy to use, some preparation is still required. Use the following check-list to prepare.

Ensure that:

• All physical connections to the rear panel have been completed.

If this is not the case, refer to Chapter 2 (Getting Started) and Chapter 3 (About the 7955) for details of supported connections.

• Front panel keyboard buttons and the menu system are familiar.

Chapters 5 and 6 are provided to assist with this. It might be a good idea to bookmark the summary of keys in Chapter 5 for quick reference.

• Identification numbers of important result data are written down.

These numbers will be required for configuring facilities such as analogue outputs. There are two ways to find out data location numbers:

(1) Examine the “.man” file that is supplied on the FC-Config1 media or

(2) Locate the data within the menu system and then press the ‘a’-key to display the unique identification number on line 4. (Pressing the ‘a’-key toggles the number display on or off.)

• Calibration certificates (and supporting data sheets) for all field instrumentation are available.

• there is a comprehensive list of all the 7955 input and output connections that are being used and a list of the measurement tasks that are required.

1 A free PC utility available to download from the website(s) listed on the back page.


Page 10.2 7955 2540 (CH10/AC)

Starting a Wizard from the front panel is easy.


Step 1: Press the MAIN-MENU key.

Step 2: Use the DOWN-ARROW key to scroll through pages until the “Configure” option appears.

Step 3: Press the blue key that is alongside the “Configure” option.

Step 4: Press the ‘a’-key twice so that “Setup Wizard” appears on line one of the display. Do not worry about what line two is presently displaying.

Step 4: Press the ‘b’-key once to start the wizard selection process.

Step 5: Use the DOWN-ARROW key to scroll through all available wizards (on line two).

Step 6: Press the ENTER key twice to select and then start a wizard that was named is on-screen.

Once a Wizard is started, follow the prompts to supply the information it asks for and then, if necessary, use Chapter 11 and the menu system to edit the resulting configuration to match your exact needs. Wizard interactions involve several keys:

a, b, c ,d keys Answer a question (e.g. “Yes” or “No”) or used for normal data location editing

ENTER key Confirm a selection or edited setting (e.g. new value), move on to next prompt

< key Go back to a previous important decision prompt.

After completing a Wizard, the screen with “Setup Wizard” re-appears. Further wizards can then be selected in the same way as before. Note that it is not necessary for the “None” option to be selected before proceeding to other 7955 work.


7955 2540 (CH10/AC) Page 10.3

10.3 Quick-view Guide (Set-up Wizards)

Wizards Measurement Tasks Comments

Full Setup • Multiple measurement tasks Skip the tasks that are not applicable.

Flow meter • Frequency (Turbine Flow)

• ‘Meter factor’ and ‘K factor’ See Chapter 11 for measurement details

Flow rate

• Gross Volume flow rate

• Indicated Standard Volume flow rate

• Gross Standard Volume flow rate

• Mass rate

See Chapter 11 for measurement details

Meter run density • Metering-run density measurements See Chapter 11 for measurement details

Base Density • Base density (API or 4x5 Matrix Referral) See Chapter 11 for measurement details

Specific gravity • Specific Gravity measurements See Chapter 11 for measurement details

Viscosity • Viscosity measurements See Chapter 11 for measurement details

Temperature • Temperature measurements See Chapter 11 for measurement details

Pressure Pressure measurements See Chapter 11 for measurement details

Sediment & Water • BSW Percentage See Chapter 11 for measurement details

Special calc. • Special Equation Type 1 See Chapter 11 for measurement details

Analogue outputs • mA signal outputs See Chapter 11 for measurement details

Pulse outputs • Pulse outputs See Chapter 11 for measurement details

Alarms • User alarms Chapter 8 is about alarms.

Multi view • Multi-page multi-view (key display) See Chapter 11 for measurement details

Communications • RS-232/485 parameters

• Peer-to-Peer, High-Speed Lists Chapter 7 is a full guide to Communications

Prover • Prover and Proving Details Chapter 16 is a full guide to Proving support

Valves • Valve control set-up See Chapter 16

HART inputs • Live inputs from SMART type transmitters Chapter 17 is a full guide to HART support

PID setup • PID Controls Refer to Chapter 9

Batch setup • Batching Refer to Chapter 18

Retro batch calc • Retrospective calculations Refer to Chapter 18

Initialise • Clear all user programming to defaults Use this with caution!!


Page 10.4 7955 2540 (CH10/AC)

10.4 Units Wizard Selection

Follow these instructions to select a standard for the units of measurement:

Step 1: Press the MAIN-MENU key.

Step 2: Use the DOWN-ARROW key to scroll through pages until the “Configure” option appears.

Step 3: Press the blue key that is alongside the “Configure” option.

Step 4: Press the blue key that is alongside this description: “Units wizard”‘

Step 5: Press the ‘b’-key once to start the selection process.

Step 6: Use the DOWN-ARROW key to scroll through all available options (see map below).

Step 7: Press the ENTER key twice to select the standard that is named is on-screen.

"Imperial"

"Metric"

Choosing this will not do anything. Use scroll up/down keysto move through the wizard options.

Units wizard(Selection)

Choose option

Metric

Imperial

SI

Exit Wizard

"SI"

Figure 10.1: Units Wizard Selection

Chapter 11 Configuring without using Wizards

7955 2540 (CH011/AF) Page 11.1

11. Configuring without using Wizards

11.1 What does this Chapter tell me? This Chapter is a configuration reference for those who are reasonably experienced with configuring the 7955 Flow Computer. It is also useful for those who provide technical support. It is primarily organised for a structured approach to configuring - the live inputs, the calculations and the live outputs - after the first power-on. However, for those in a support role, a ‘quick-find’ index is provided for locating just the reference pages required for configuring and trouble-shooting a measurement task.

If you are not experienced, return to Chapter 10 (Wizards) unless directed here by this manual or by someone providing technical support.

Not all features are covered in this Chapter. For example, configuring for HART and flow meter proving is a complex task and therefore kept in separate chapters. Some optional features are in Chapter 9.

Quick-find Index.............................…............ 11.2

A structured approach to configuring…......... 11.3

Reference Page Conventions............…........ 11.5

Reference information........................…....... 11.6+

Rounding Compliance Statement

Liquid Flow Computer software complies with the API standard for rounding down the floating-point values of live density and base density referral measurements. The rounding procedure is also applied to all inputs to the referral calculations (e.g. temperature) and auxiliary outputs from the referral calculations (e.g. CTL). Relevant sections in the standard are API 12.2 and API 11.1 VOL X.

By default, rounding is inactive. It can be activated for the next cycle by navigating to the <”Rounding”> configuration menu and then editing the multiple-choice option. When active, we recommend you change the displayed measurement units of associated parameters to metric units


Page 11.2 7955 2540 (CH011/AF)

11.2 Quick-find Index Use this table to quickly find the pages that are of interest.

Category Measurement Task 1st. Page Notices

• Analogue Inputs (mA and RTD/PT100) 11.06

• Digital (Status) Inputs 11.07 Live Inputs • Pulse Inputs (Turbine and Prover) 11.08

• Turbine/Positive Displacement 11.010

• Orifice (δP) 11.17 Flow

Metering System • Coriolis 11.29

• Totalising by metering-point 11.32 Totalising • Totalising by Station 11.34

• Header ‘density’ fluid temperature 11.35 • 1x4x1 scheme only

• Header ‘viscosity’ fluid temperature 11.36 • 1x4x1 scheme only Temperature • Metering-point fluid temperature 11.37

• Header pressure 11.38 • 1x4x1 scheme only Pressure • Meter-run pressure 11.39

• Header ‘density sample loop’ density 11.40 • 1x4x1 scheme only

• API referral (header base and base run) 11.46 • 1x4x1 scheme only

• 4x5 referral (header base and base run) 11.47 • 1x4x1 scheme only

• Known fluid density (GPA, IUPAC, etc.) 11.48 • 1x4x1 scheme only

• Metering-point fluid density 11.50 • 4x4x4 scheme only

• Known fluid base density (GPA, IUPAC, etc.) 11.52 • 4x4x4 scheme only

• Specific gravity 11.53

• Degrees API 11.53

Density Measurement

System

• Special Equation Type One 11.54

• Header ‘viscosity sample loop’ density 11.55 • 1x4x1 scheme only

• Header viscosity (from 7827s) 11.57 • 1x4x1 scheme only

• Referred viscosity (base and meter viscosity) 11.60 • 1x4x1 scheme only

Viscosity Measurement

System • Metering-point viscosity 11.62 • 4x4x4 scheme only

BS&W • Prime selected BS&W analyser channels 11.63

• Net % and ρ calculations 11.65

• Net flow rates and totals (by metering-point) 11.71 Net Oil/Water • Net flow rates and totals (by Station) 11.73

• 1x4x1 scheme only

• Product detection system Interface Detection • Product totals

11.79

• Analogue Outputs 11.83

• Digital (Status) Outputs 11.84 Live Outputs • Pulse Outputs 11.85

7955 Security • Passwords and security levels

• Security level fallback 11.86

Multi-view • Multi-page Multi-view display 11.88


7955 2540 (CH011/AF) Page 11.3

11.3 A structured approach to configuring Preparation will help ensure that configuration work progresses smoothly. At this stage, it is expected that all the connections have already been made to the 7955. If possible, check on this by asking the relevant authority. Familiarity with the front panel keyboard and menu system is also expected. Work through the preparation and configuration stages that are listed below.

11.3.1 Preparation stage 1. Ensure that all of the information needed is at hand:

• A plan of the pipeline layout.

• A summary of instrumentation connected to the 7955, providing inputs or expecting outputs. Include the type of logical connections made to the rear panel of the 7955. (e.g. a mA type pressure transmitter wired to analogue input 3)

• Calibration certificates of connected instrumentation

• Operational data (e.g. minimum and maximum flow rates)

• A summary of core measurements to be set-up (e.g. flow rates, flow totals, density, etc.) (It may be useful to look in Chapter 3 and browse through this Chapter).

• Identification numbers of data that is important (This is only for configuring multi-page multi-view and analogue outputs that can require the input of a location number).

• A plan of what is required from additional features (e.g. Batching, Archiving, etc.) (It may be useful to look in Chapter 9 and browse through this Chapter).

2. Read the information on conventions used.

3. Browse through the rest of this Chapter and see how the reference pages are organised.

(End of preparation stage)

11.3.2 Configuration stage 1. Get the 7955 into the Programmer security level.

(Turn the security key to the far right or type in the “Programmer” password to change level) 2. Set the display contrast, display formats and the system cycle time.

• Display contrast may be quite dim when first powering on the 7955 with new software. Look in the <“configure”>/<“Additional features”> menu for the appropriate menu and then change the setting to suit the environment.

• Display formats are important when decimal places of results are critical. They are categorised under

general headings (e.g. temperature, pressure, etc.). Look in the <“configure”>/<“Additional features”> menu for the appropriate menu and then change the settings if the defaults are not appropriate. Units of measurement can be changed also.

• The machine cycle time is dependent on how much work the 7955 is performing. Examine the idle

cycle time indicator in the <“Health Check”> menu to see if the cycle time needs to be increased or decreased.

DO NOT CHANGE ANY SETTINGS UNDER THE CALIBRATION MENUS. SETTINGS ARE MADE BY SPECIALIST CALIBRATION EQUIPMENT AT THE FACTORY.


Page 11.4 7955 2540 (CH011/AF)

3. Configure the live (transmitter) inputs to get raw readings from instrumentation.

• HART Inputs All reference information is in Chapter 17. • Analogue Inputs Turn to page 11.6

4. Choose either the 1x4x1 Scheme or the 4x4x4 Scheme.

• Navigate to this menu: <“Configure”>/<“Transducer details”> • Locate the menu data page for “Flow system type” • Change the selection to the applicable scheme.

5. Set-up the calculation processes.

Pulse inputs, flow details, flow rates, sediment & water, flow totals, temperature, pressure, density, specific gravity, degrees API, viscosity, interface detection and special equation type one.

6. Configure the live outputs.

• Analogue Outputs Turn to page 11.83 • Pulse Outputs Turn to page 11.85

7. Multi-view Multi-page display (User key 1) 8. Alarms and Events

(All reference information is in Chapter 8) 9. Serial communications ports

(All reference information is in Chapter 7) 10. Set-up 7955 security

Set passwords for security levels and set-up the optional security fallback feature. (If not using the security key, change to the Engineer security level for the remainder of the configuration work).

(End of configuration stage)


7955 2540 (CH011/AF) Page 11.5

11.4 Reference Page Conventions Most reference pages consist of:

• A short bullet-point list of measurements that can be set-up • A drawing of the process showing key blocks and how data interacts • Menu references • A list of menu data associated with the process drawing

Other reference pages consist of a brief explanation but no diagram. Menu references and a list of menu data are always present.

Menu reference notation

A notation has been used as a much shorter method of explaining how to move from the present menu to another menu.


Step 1: Press the MAIN-MENU key Step 2: Use the DOWN-ARROW key to scroll through pages until the word “Configure” is seen. Step 3: Press the blue (letter) key that is alongside the word “Configure”. Step 4: Use the DOWN-ARROW key to scroll through pages until the word “Flow rate” is seen. Step 5: Press the blue (letter) key that is alongside the word “Flow rate”. Sometimes, it is convenient to use the MAIN-MENU key (especially if lost). However, use of the BACK-ARROW key is a much more common method of returning back a menu level. Note: The structure of menus varies in other software versions and releases.

Multiple metering-run notation

(a) Multiple metering-run menu data

Three symbols, “ “, have been used in this Chapter to notify that a copy (instance) of a menu data is provided for each of the four metering-runs (streams). Each copy has the same on-screen name but the applicable metering-run can always be identified by a single digit near the triangular marker on line 4. Use of the METERING-POINT SELECT key is required to change the digit and, therefore, select another metering-run. The absence of this digit means that there is one copy to be shared between all metering-runs.

(b) Installation layout

Pages with one of the following terms are only relevant to a certain installation layout.

“1x4x1” Header (common input) forks into 4 separate metering runs (streams) and then re-forms a single output.

“4x4x4” No Header but 4 separate metering runs


Page 11.6 7955 2540 (CH011/AF)

11.5 ANALOGUE INPUTS

Feature: (Note: Rear panel pin connection information is located in Chapter 2)

• Analogue Inputs supported by 7955

RTD/PT100 input channels (Analogue inputs 1 to 4) mA input channels (Analogue inputs 1 to 16)

What to do: This reference page will assist when configuring basic data for all analogue channels that are being used. After each analogue channel is set-up, check that a “Live” reading - a percentage by default - is being displayed by the corresponding <Input Channel> menu data page. A “Fail” status indicates an absent or failed transmitter. Later reference pages will expect all instrumentation to be already wired to the 7955 and expect there to be a live reading. Configuring a measurement task will involve setting range (scaling) information and selecting the appropriate analogue channel as the source. Menu Navigation List: (1) <“Configure”>/<“Inputs”>/<”Analog inputs”> and (2) <“Health check”>/<“Inputs”>/<”Analog inputs”> Menu Data List: * shows data that can be “Live” or “Set”

Analogue Channel (and signal types)




Input channel 1 * Input channel 9 * Analog input1 type Analog input9 type

Analogue Input 1 1 (RTD/PT100 or mA)

mA input 1 ave type

Analogue Input 9 (mA only)

mA input 9 ave type



mA input 2 ave type


mA input 10 ave type



mA input 3 ave type





mA input 4 ave type





mA input 5 ave type





mA input 6 ave type





mA input 7 ave type





mA input 8 ave type



1 There is a DIP switch block on the processor board for deciding if this is a mA-type input or a RTD/PT100-type input.


7955 2540 (CH011/AF) Page 11.7

11.6 DIGITAL INPUTS

Feature: (Note: Rear panel pin connection information is located in Chapter 2) • Digital inputs supported by 7955

Status Input channels 1 to 26 What to do: This reference page will assist when configuring basic data for all the status input channels that are being used. Later tasks, such as proving, will expect this configuration data to be already set-up. No digital inputs have a default function. However, they can be allocated a function when setting up proving (Chapter 16) and/or when requiring any of the following:

Remote Print: Transmit a current report through serial ports configured for connection to an ASCII compatible output device, such as a printer. Selection of the status input is made using a parameter, <”Remote print Din”>

Maintenance-mode: Attempt a switch to “maintenance-mode” from the “normal” mode, simultaneously for all metered runs. Selection of the status input is made using a parameter, <”Maint mode req Din”>.

(This function requires the Flow Computer to be in a “Flow Stopped” state)

Within the <“Health Check”> menu there are 2 Status Input sub-menus. Each contains a menu data page with a series of digits on the second line. Each digit indicates the present state of an individual input

Menu Navigation List: (1) <“Configure”>/<“Inputs”>/<”Status inputs”>, (2) <“Configure”>/<”Inputs”>/<“Input assignment”> and (3) <“Health check”>/<“Inputs”>/<”Status inputs”> Menu Data List: * shows data that can be “Live” or “Set”

Status I/P Channel


Status I/P Channel


Status I/P Channel


DIN 1 logic level DIN 11 logic level DIN 21 logic level 1 DIN 1 mode level

11 DIN 11 mode level

















DIN 7 logic level DIN 17 logic level 7 DIN 7 mode level








d

b

c

Status in [1-16]0010010000100000

a

This Status Inputis presently active

(positive logic)

Status Input #16


Page 11.8 7955 2540 (CH011/AF)

11.7 PULSE INPUTS

Feature: (Note: Rear panel pin connection information is located in Chapter 2)

• Pulse inputs supported by 7955

Pulse input channels 1 to 4 (for use by pulse based volumetric/mass flow meters) Pulse input channel 5 (for use by Master Meter Proving feature – see Chapter 16))

Figure 11.7-1: Pulse Input Processing

PULSE TRAIN 'A' PulseComparison(IP 252/A)

PULSEFREQUENCY

fPULSE TRAIN 'B'

PULSE TRAIN 'A'PulseCount

f

MethodSelection

ERRORPULSES

PULSECOUNT

What to do: Use this reference page to configure the basic live input data for any of the channels. The reference pages for configuring further flow metering details will expect the instrumentation to be already wired to the 7955 and expect the “Live” pulse frequency. Proving is described in Chapter 16.

After each channel is set-up, check on the pulse frequency that is being indicated by the <”Flowmeter freq”> software parameter. Also, use the “Health Check” menu to view other diagnostic information such as a missing pulse counter. Menu Navigation List: (1) <“Configure”>/<“Inputs”>/<“Pulsed flow inputs”>, (2) <“Health check”>/<“Inputs”>/<“Pulse inputs”> and (3) <“Health check”>/<“Inputs”>/<“Flow meter inputs”>/<”Turb/Coriolis/PD”> Menu Data List: * shows data that can be “Live” or “Set”

Pulse Channel (and allocation)

Menu Data (as displayed) Notes? Pulse Channel

(and allocation) Menu Data

(as displayed) Notes?

Flowmeter freq * B Flowmeter freq * B Meter 1 i/p type D Meter 4 i/p type D Meter 1 error lmt A, E Meter 4 error lmt A, E Pulse input 1 value Pulse input 4 value Err Pulse ip 1 value C Err Pulse ip 4 value C

Pulse Input 1 (Metering-point 1)

Pulse ip 1 sample


Pulse ip 4 sample

Flowmeter freq * B Prove meter freq * B

Meter 2 i/p type D Meter 5 i/p type D Meter 2 error lmt A, E Meter 5 error lmt A, E Pulse input 2 value Pulse input 5 value Err Pulse ip 2 value C Err Pulse ip 5 value C


Pulse ip 2 sample

Pulse Input 5 (Master Meter Proving)

Pulse ip 5 sample

Flowmeter freq * B

Meter 3 i/p type D Meter 3 error lmt A, E Pulse input 3 value Err Pulse ip 3 value C


Pulse ip 3 sample

Notes are listed on the next page.

Note: Coriolis flow metering support automatically selects the single pickup pulse train method.


7955 2540 (CH011/AF) Page 11.9

CONFIGURATION REFERENCE PULSE INPUTS Notes: A The ‘error limit’ is a watchdog for the count of missing pulses that are accumulated over a single machine cycle.

When the ‘error limit’ is exceeded, the error counter is reset to zero and an alarm is raised. B The pulse frequency is calculated using the following equation:

Using: F = tP

Where: F = Pulse frequency

P = Number of pulses accumulated since time ‘t’ {Health check menu data is <Err Pulse ip N value> where ‘N’ identifies the pulse input}

t = Elapsed time (in seconds) since the last pulse count for this calculation. {Health check menu data is <Pulse ip N sample> where ‘N’ identifies the pulse input}

The “LIVE” pulse input channels are read every 100ms. Accumulated pulses are then displayed every cycle.

C Counter for missing (error) pulses during the present machine cycle. There is also a software-based totaliser

for accumulating the number of missing pulses from each cycle. D When receiving the frequency output from a Coriolis mass flow meter, a single pulse train is assumed

irrespective of the option selected for the type. Consequently, the IP252/A routine is not applied. E The programmed (SET) error limit for missed pulses each cycle is not applicable unless there are dual pickup

pulse trains being received by the Flow Computer.


Page 11.10 7955 2540 (CH011/AF)

11.8 TURBINE/POSITIVE DISPLACEMENT FLOW

Measurements and Features Supported: • Indicated Volume flow rate - at up to four metering points • Gross volume flow rate - at up to four metering points • 4 x flow meter calibration curve options

Figure 11.8-1: Turbine Flow/Positive Displacement Flow Blocks and Parameters

Index for use with listof associated dataXX

1 fPULSE

FREQUENCY(from a Pulse Input)

42

3

HI

Flow StopThreshold

METER-RUNKINEMATICVISCOSITY

fIndicated

Volume RateCalculation

f

"Correction"route

"Conversion"route

"4 x (K v Freq)"route

"Polynomial"route

IndicatedVolume RateCalculation

96

f

K FactorCalculation

962565

f82

4 Curve Profiles

K FactorCalculation

75265

f

807681

Hysteresis

Calibration Certificate

Kf

96f

82

GrossVolume RateCalculation

GrossVolume RateCalculation

Meter FactorCalculation

982565

GrossVolume RateCalculation82

Kf

Kf

ν ν

CalibrationCertificate


958483

Polynomial Factors

98 GrossVolume RateCalculation82

100

HI

101

LO

99

MF

MF

QGV

QGV

QGV

QGVIndicated


IndicatedVolume RateCalculation

98

97

MF

QIV

97QIV

97QIV

QGV

97QIV

98MF

FLOWTOTALLING

FLOWTOTALLING FLOW

TOTALLING

FLOWTOTALLING

FLOWTOTALLING

96 102

Kf

102

102

102

102

Menu Navigation List: (1) <”Configure”>/<”Inputs”>/<”Flow meter”>, (2) <“Configure”>/<“Flow rate”> and (3) <“Health check”>/<“Inputs”>/<”Flowmeter inputs”>

Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 1 Flowmeter freq * A, 46 Curve3 K at Q1 2 Meter freq HI limit : : : :

3 Flow stop threshold 55 Curve3 K at Q10 4 Meter curve type 56 Curve4 K at Q1 5 Meter curve points : : : :

6 Error% / Kfactor 1 65 Curve4 K at Q10 : : : : 66 Frequency Q1

15 Error% / Kfactor 10 : : :

16 Flow/freq 1 75 Frequency Q10 : : 76 Curve1 visc LO limit

25 Flow/freq 10 77 Curve2 visc LO limit 26 Curve1 K at Q1 78 Curve3 visc LO limit : : 79 Curve4 visc LO limit

35 Curve1 K at Q10 80 Curve4 visc HI lim 36 Curve2 K at Q1 81 Hysteresis : : : : ν Meter kinematic visc *

45 Curve2 K at Q10 82 Curve selected

See next page for notes and continued menu data list.


7955 2540 (CH011/AF) Page 11.11

CONFIGURATION REFERENCE TURBINE/PD FLOW METERING (Menu Data List continued…) * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes?

83 Polynomial degree 98 Meter Factor *

84 Polynomial coeff a0 99 Gross vol rate

: : : : 100 Gross vol HI lmt

95 Polynomial coeff a10 101 Gross vol LO lmt

96 Flowmeter K factor * 102 Rate flowstop action C

97 Ind vol rate * (C) - Flow meter type

Notes: (X) – Indirectly mentioned in note X

There is an instance (copy) of this data available for each of four metering-points. Each instance has the same on-screen parameter description but a metering-point can be identified by a single digit near the triangular marker on line 4. The absence of this digit means that there is one instance to be shared between all metering-points.

A Refer to Section 11.7 (on page 11.8) for details of configuring this parameter B There are four calibration curve options supported:

(1) “Conversion K v Hz”

A ‘K-factor’ is interpolated, once during every machine cycle, from a user-programmable calibration curve. The ‘Meter factor’ (MF) is a fixed (SET) value. A SET MF value can still be updated by a proving session, by product detection, or by a MODBUS networked device. Also, see Figure 11.8-1 on page 11.12.

(2) “Correction% v flow” (Default Option)

The ‘Meter Factor’ (MF) is calculated, once during every machine cycle, by a relative error (percentage) correction process. The ‘K-factor’ is a fixed (SET) value. They may then be updated by a proving session, by product detection or by a MODBUS networked device. Also, see page 11.12.

(3) “4 visc x (K v Hz)” (Viscosity Corrected Flow)

A ‘K-factor’ is interpolated, once during every machine cycle, from one of four programmable calibration curves. Curve selection is determined by the present viscosity range. The ‘Meter factor’ (MF) is a fixed (SET) value. Also, see Figure 11.8-2 on page 11.12.

(4) “UCC polynomial” (Viscosity Corrected Flow)

The ‘K-factor’ is a fixed (SET) value. A ‘Meter Factor” (MF) is calculated, once during every machine cycle, using the polynomial equation from Section 3.3.3.2 of the ISO 4124:1994(E) International Standard.

Parameters to be programmed into the Flow Computer are the pre-generated factors (a0, a1, etc.) for an established curve fit and the polynomial degree. (Viscosity measurements must also be set-up).

This method is for when using some turbines, such as helecoidal two-blade turbine meters, to meter multi-product oils or meter products where large viscosity variations can occur. Full details of the method are provided in the ISO 4124:1994(E) International Standard.

Proving sessions can overwrite either a ‘Meter Factor’ value or the ‘K-factor’ value. It is dependent on how proving is configured and if the prove session is successful. (See Chapter 16)

Product detection can also overwrite a ‘Meter Factor’ (MF) value and/or the ‘K-factor’ value.

C By default, the Flow Computer calculates and displays live flow rates under a ‘Flow stop’ condition, even

when there is negligible flow. However, displayed rates can be forced to zero by selecting the option descriptor with “Zero flow rates”.

(Calculations using a flow rate value as an input will always get zero values during ‘Flow stop’) D Keep both ‘HI’ and ‘LO’ limits programmed (SET) with a zero value if an alarm limit check on the associated

parameter is not required.


Page 11.12 7955 2540 (CH011/AF)

TURBINE/PD FLOW METERING CONFIGURATION REFERENCE

Figure 11.8-1: ‘K Factor’ v Pulse Frequency Calibration Curve

• Curve profile with four points programmed.

• The lowest frequency on curve is point (F1, Kf1). This point corresponds to the <“Flow/freq 1”> menu data page value and the <“Error% / Kfactor 1“> menu data page value respectively.

• Highest frequency on curve is point (F4, Kf4). This point corresponds to <“Flow/freq 4”>, <“Error% / Kfactor 4“>.

• Point (FM, Kfm) corresponds to a live pulse frequency and a resulting ‘K Factor’.

Figure 11.8-2: 4 x ‘K- factor’ v Pulse Frequency Calibration Curves (Viscosity Corrected Flow)

Quad curve profiles. A curve is selected by checking the metering-run kinematic viscosity value against range limits for each curve.

Lowest frequency on curve 1 is point (F1, Kf1). This corresponds to <“Frequency Q1”> menu data and <“Curve 1 K at Q1”> menu data respectively.

Highest frequency on curve 1 is point (F5, Kf5). This corresponds to <“Frequency Q5”> menu data and <“Curve 1 K at Q5”> menu data respectively.

Point (FM, Kfm) corresponds to a live pulse frequency and a resulting ‘K Factor’ from the selected curve.

For the purpose of this example, C3 is the selected curve with the Meter Kinematic Viscosity value falling in the appropriate range for that curve. The Flow Computer re-checks the range every machine cycle. Hysteresis can be used with the viscosity ranges to avoid frequent switching between two curves. ‘Meter Factor’ from Flow versus Error Percentage Calibration Curve Turbines are supplied with a calibration certificate that describes the actual flow rates against percentage error in readings by a test meter.

Table 11.8.1: Example of Certificate Data

Flow rate (m3/h) 100 160 280 400

Error % -0.24 0.06 0.17 0.11

The raw data on the certificate has to be turned into turbine corrected values by the Flow Computer. To do this, a single curve profile must be set-up in the following way:

Menu Data (as displayed) Value or Option Meter curve type “Correction% v flow” Please note that this is an example and that only data

Meter curve points “4 curve points” from the calibration certificate of the turbine should Flow/freq 1 100 be entered into the Flow Computer. Flow/freq 2 160 Flow/freq 3 280 Flow/freq 4 400

Error% / Kfactor 1 -0.24 Error% / Kfactor 2 0.06 Error% / Kfactor 3 0.17 Error% / Kfactor 4 0.11

'K' Factor(Pulse/m3)

Kf1

Kf3

Kf2

Kf4

F1 F2 F3 F4

PulseFrequency

Kfm

Fm

F2

'K' Factor

F3

Kf5

PulseFrequency

KfM

F1

FM

F4

F5

Kf4 Kf3 Kf2 Kf1

C2

Kinematic Viscosityrange for the curve.

C1 C3 C4


7955 2540 (CH011/AF) Page 11.13

CONFIGURATION REFERENCE TURBINE/PD FLOW METERING

Turbine corrected values are not displayed within the menu system but the calculations used are as follows:

Where:

tV = Corrected volume from test turbine

aV = Actual volume (e.g. 100 from the above data)

tE = Corrected percentage error in test turbine reading

aE = Actual error in Vt reading (e.g. -0.24 from the above data)

The calculations use the ‘Set’ curve profile data to get a modified curve.

Table 11.8.2: Example Modified Curve with Turbine Corrected Values

Flow rate (m3/h) 99.76 160.096 280.476 400.44

Error % -0.241 0.05996 0.1697 0.1098 With a ‘Live’ (or ‘Set’) indicated volume flow rate an error percentage can be linearised from the modified curve. The error percentage is then used to adjust the present ‘Meter Factor’ value.

( )a

att V

VVE

100**= a

aat V

EVV +⎟⎟

⎠

⎞⎜⎜⎝

⎛=

100

*


Page 11.14 7955 2540 (CH011/AF)

TURBINE/PD FLOW METERING ADDITIONAL FLOW RATES

Features: • Indicated Standard Volume flow rate - at up to four metering points • Gross Standard Volume flow rate - at up to four metering points • Mass flow rate - at up to four metering points

Figure 11.8-3: More Turbine/PD Flow Rate Blocks and Parameters

IndicatedStandard


97

Volume CorrectionFactor Calculation

108Input DataSelection

107

Gross StandardVolume RateCalculation

97

Combined CorrectionFactor Calculation

109Input DataSelection

107104

105

106

103

115

Mass RateCalculation

99

105

114

113

HI

LO

112

111

110

HI

LO

118

117

116

HI

LO

98

104

105

106

103

98

102CTL

CPL

CPL

CTL

MF

MF

ρMeter

ρMeter

ρBase

ρBase

QIV

QIV

QISV

QGSV

QGV

ρMeter

102

Qm

102

VCF

CCF

102

Flow Totalling

Flow Totalling

Flow Totalling

Menu Navigation List: (1) <“Configure”>/<“Flow rate”>, (2) <”Flow rates”>, (3) <“Density”> and (4) <“Configure”>/<“Base density”>



97 Ind vol rate * , (A) 109 Combined cor factor * 98 Meter Factor * 110 Ind std vol rate * , (A) 99 Gross vol rate * , (A) 111 Ind std vol HI lmt B, 102 Rate flowstop action A 112 Ind std vol LO lmt B, 103 CTL 113 Gross std vol rate * , (A) 104 CPL 114 Gross std vol HI lmt B, 105 Meter run density * 115 Gross std vol LO lmt B, 106 Base density * 116 Mass rate * , (A) 107 Base dens method 117 Mass rate HI limit B, 108 Volume cor factor * 118 Mass rate LO limit B,

Notes: (X) – Indirectly mentioned in note X There is an instance (copy) of this data available for each of four metering-points. Each instance has the

same on-screen parameter description but a metering-point can be identified by a single digit near the triangular marker on line 4. The absence of this digit means that there is one instance to be shared between all metering-points.

A By default, the 7955 calculates, for display purposes only, the actual live flow rates under a ‘Flow stopped’ condition, even when there is negligible flow. However, display can be forced to show zero flow by selecting the multiple-choice option with “Zero flow rates”. (Calculations using a flow rate will always use a zero value during a “Flow Stop” condition)

B Keep both ‘HI’ and ‘LO’ limits programmed (SET) with a zero value if this alarm limit check on the associated parameter is not required.


7955 2540 (CH011/AF) Page 11.15

EQUATION LIST TURBINE/PD FLOW METERING Equation List:

Equation TU#1: Indicated Volume flow rate

Using: QIV =

3600*⎟⎟⎠

⎞⎜⎜⎝

⎛

fKf

Where: QIV = Indicated Volume flow rate (m3/hour)….….…… {Menu Data: <”Ind vol rate”>}

f = Flowmeter (pulse) frequency (pulse/sec)…...…. {Menu Data: <”Flowmeter freq”>}

Kf = ‘K factor’ (pulses per m3)…………..……………..{Menu Data: <”Flowmeter K factor”>}

Equation TU#2: Gross Volume flow rate

Using: QGV = MFQIV * Where: QGV = Gross Volume flow rate (m3/hour)………....…… {Menu Data: <”Gross vol rate”>}

QIV = Indicated Volume flow rate (m3/hour)….….…… {See Equation TU#1}

MF = Meter Factor………………………………………. {Menu Data: <”Meter factor”>}

Equation TU#3: Volume Correction Factor

Using: VCF = CPLCTL * ........………….…………….………. (API)

Or: VCF =⎟⎟⎠

⎞⎜⎜⎝

⎛

Bρρ

...................…….………………………...(4x5)

Where: VCF = Volume correction factor…………………...……. {Menu Data: <”Volume cor factor”>}

CTL = API temperature correction factor…….…..……. {Menu Data: <”CTL”>}

CPL = API pressure correction factor……..……………. {Menu Data: <”CPL”>}

And: ρ = Fluid density at a metering-point…….…….....… {Menu Data: <”Meter run density”>}

ρΒ = Fluid density at base conditions….….…….....… {Menu Data: <”Base density”>} (Note: The equation choice is linked to the selected method for density referral)

Equation TU#4: Combined Correction Factor

Using: CCF = MFCPLCTL ** …………………...………….. (API)

Or: CCF =⎟⎟⎠

⎞⎜⎜⎝

⎛MF

B*

ρρ

.......……………………………….. (4x5)

Where: CCF = Combined correction factor………..……...……. {Menu Data: <”Combined cor factor”>}

CTL = API temperature correction factor…….…..……. {Menu Data: <”CTL”>}

CPL = API pressure correction factor……..……………. {Menu Data: <”CPL”>}

MF = Meter Factor………………………………………. {Menu Data: <”Meter factor”>}

And: ρ = Fluid density at a metering-point…….…….....… {Menu Data: <”Meter run density”>}



Page 11.16 7955 2540 (CH011/AF)

TURBINE/PD FLOW METERING EQUATION LIST (Equation List continued…)

Equation TU#5: Indicated Standard Volume flow rate

Using: QISV = QIV * VCF

Where: QISV = Indicated Standard Volume flow rate…...……… {Menu Data: <”Ind std vol rate”>}


VCF = Volume correction factor…………………...……. {See Equation TU#3} Equation TU#6: Gross Standard Volume flow rate

Using: QGSV = QIV * CCF

Where: QGSV = Gross Standard Volume flow rate……….……… {Menu Data: <”Gross std vol rate”>}


CCF = Combined correction factor…………………..…. {See Equation TU#4} Equation TU#7: Mass flow rate

Using: QM = QGV * ρ

Where: QM = Mass flow rate (kg/hour)……………...………….. {Menu Data: <”Mass rate”>}

QGV = Gross Volume flow rate (m3/hour)………....…… {See Equation TU#2}

ρ = Fluid density at a metering-point…….…….....… {Menu Data: <”Meter run density”>}


7955 2540 (CH011/AF) Page 11.17

11.9 ORIFICE FLOW METERING (ISO 5167-1 2)

Measurements Supported: • Prime selected Differential Pressure – at up to four metering points • Mass rate – at four metering points - from ISO 5167-1 (this page), AGA 3 (page 11.18) or HART Input (page 11.19) • Gross Volume flow rate – up to four metering points – turn to page 11.19

InitialSourcesSelection

12

Δ P

mA Inputs

6

(HART) δP

HART Inputs

4

D.P. CellConfig. &Selection

Δ PD.P.Calculations

(Scaling)

9

7

10

Range Details

8

11

24

13 1420

21

22 23

HI

FLOWSTOP

F/B

OrificeCalculations

(Plate)

OrificeSelect

25

15 16 17 18

19Method

Selection

ρ 45

46

OrificeCalculations

(V-Cone)

OrificeCalculations

(Venturi)

HARTMethod

AGA 3Method

MASSFLOWRATE

Intermediate Results



26 32To

35 44To

26 33To

35 41To

26 32To

35 45To

47

34tP

tP

Pt

XX Index for use with listed data

45

46

44

ρ 45

ORρ 45

3 51 2

%

Menu Navigation List:

(1) <“Configure”>/<”Inputs”>/<“Flow meter”>, (2) <“Health check”>/<”Inputs”>/<“Flowmeter inputs”>/<“Orifice”>, (4) <“Configure”>/<“Flow rate”>, (5) <“Density”>/<”Meter density”>, (6) <“Pressure”>/<”Meter pressure”>, (7) <”Temperature”>/<“Meter temperature”> and (8) <“Health check”>/<”Flow meter details”>/<”Orifice”>


Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? - Flow meter type 26 Orif pipe diameter 1 DP cell 1 source A, 27 Orifice diameter 2 DP cell 2 source A, 28 Meter dynamic visc * L, 3 DP cell 3 source A, 29 Orifice isentropic 4 DP cell 4 source A, 30 Pipe expans coeff 5 DP cell 5 source A, 31 Orif expans coeff 6 Diff press HI 100% 32 Orifice cal temp 7 Diff press HI 0% 33 Orif tapping code 8 Diff press MED 100% 34 Venturi type 9 Diff press MED 0% 35 Orif discharge coeff J

10 Diff press LO 100% 36 Orif expandability J 11 Diff press LO 0% 37 Orif vel of approach J 12 Diff press config B, 38 Reynolds number 13 Diff press HI switch C 39 Orif corr pipe dia 14 Diff press LO switch C 40 Orif corr pipe diam 15 Diff press cal error D, 41 Orifice beta 16 Diff press cal time D, 42 Pressure loss 17 DP deviation limit E, 43 Pressure ratio 18 DP input alarms F 44 Orif mass K factor 19 Diff press range G 45 Meter run density * 20 Diff press HI lmt 46 Mass rate * H, 21 DP flow stop limit (I), 47 Orif mass flow calc 22 Diff press FB type t MeterRun temperature * 23 Diff press FB val P Meter run pressure * 24 Diff pressure value * - Rate flowstop action I 25 Orifice type - Flow status I,

Notes are on page 11.20.

2 Standards used: ISO 5167-1:1991 and ISO 5167-1:1991/Amd.1:1998(E). Refer to the Standard for details of restrictions.

ISO 5167-1 OPTION


Page 11.18 7955 2540 (CH011/AF)

ORIFICE FLOW METERING (AGA 3 3)

Measurements Supported: • Prime selected Differential Pressure – at up to four metering points • Mass flow rate - at up to four metering points - from AGA 3, ISO 5167-1 (page 11.17) or HART Input (page 11.19) • Gross Volume flow – up to four metering points – turn to page 11.19

Figure 11.9-1: Orifice Flow (AGA 3) Blocks and Parameters

InitialSourcesSelection

12

Δ P

mA Inputs %

6

(HART) Δ P

HART Inputs

3

D.P. CellConfig. &Selection

ΔPD.P.Calculations

(Scaling)

9

7

10

Range Details

8

11

24

13 1420

21

22 23

HI

FLOWSTOP

F/B

OrificeCalculations

(Plate)15 16 17 18

19

40

Mass RateCalculation

(AGA 3)

Kf

ρ Meter

4142

HARTMethod

ISO 5167Method

MASSFLOWRATE

IntermediateResults

25 32To

33 39To

43t

P

XX Index for usewith listed data

424 5

1 2

Qm


(1) <“Configure”>/<”Inputs”>/<“Flow meter”>, (2) <“Health check”>/<”Inputs”>/<“Flowmeter inputs”>/<“Orifice”>, (4) <“Configure”>/<“Flow rate”>, (5) <“Density”>/<”Meter density”>, (6) <“Pressure”>/<”Meter pressure”>, (7) <”Temperature”>/<“Meter temperature”> and (8) <“Health check”>/<”Flow meter details”>/<”Orifice”>


Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? - Flow meter type 25 Orif pipe diameter 1 DP cell 1 input src A, 26 Orifice diameter 2 DP cell 2 input src A, 27 Meter dynamic visc * L,

3 DP cell 3 input src A, 28 Orifice isentropic 4 DP cell 4 input src A, 29 Pipe expans coeff 5 DP cell 5 input src A, 30 Orif expans coeff 6 Diff press HI 100% 31 Orifice cal temp 7 Diff press HI 0% 32 Orif tapping code 8 Diff press MED 100% 33 Orif discharge coeff J

9 Diff press MED 0% 34 Orif expandability K

10 Diff press LO 100% 35 Orif vel of approach J

11 Diff press LO 0% 36 Reynolds number 12 Diff press config B, 37 Orif corr pipe dia 13 Diff press HI switch C 38 Corr orif diameter 14 Diff press LO switch C 39 Orifice beta 15 Diff press cal error D, 40 Orif mass K factor 16 Diff press cal time D, 41 Meter run density * 17 DP deviation limit E, 42 Mass rate * H, 18 DP input alarms F 43 Orif mass flow calc 19 Diff press range G t MeterRun temperature * 20 Diff press HI lmt P Meter run pressure * 21 DP flow stop limit (I), - Rate flowstop actions I 22 Diff press FB type - Flow status I, 23 Diff press FB value 24 Diff press value *

Notes are on page 11.20.

3 Standard used: AGA Report 3 (November 1992, Third edition). Refer to the Standard for details of restrictions.


7955 2540 (CH011/AF) Page 11.19

ORIFICE FLOW METERING (HART)

Measurements Supported: • Mass Rate at the metering point - from a HART Input or from ISO 5167 (Page 11.17) or from AGA 3 (Page 11.18) • Gross Volume flow rate at the metering point

SourceSelection

7

AGA 3Method

ISO 5167Method

MASSRATE

HART Inputs

1 23

4 65F/B

8HI

LO

GrossVolume

(Calculation)

ρ Base

9GROSS

VOLUMERATE

QGVQm OR

Qm


(1) <“Configure”>/<“Flow rate”> (2) <“Configure”>/<”Inputs”>/<“Flow meter”> (3) <”Density”>/<”Base dens”>



- Flow meter type 7 Mass rate *

1 Mass rate HART chl 8 Rate flowstop action I 2 Orif mass flow calc 9 Gross vol rate * **,

3 Mass rate HI limit ρB Base density *

4 Mass rate LO limit - Flow status I,

5 Mass rate FB type

6 Mass rate FB value

Notes are on page 11.20 ** See “Orifice Equation List” Section


Page 11.20 7955 2540 (CH011/AF)

ORIFICE FLOW METERING (ISO 5167-1/AGA3/HART)

Notes: (for “Orifice Flow Metering” pages)

A By default, every ΔP measurement channel is configured to use the transmitter wired to Analogue Input ‘1’. Re-configure ΔP measurement channels to use other live inputs by editing the source selection menu data page.

A cell can be connected to any available analogue input or even attached to a HART network loop. If using HART, any unique HART (protocol) address can be given to a cell. (Refer to Chapter 17 for HART coverage)

Do not be concerned about the effect of an unused cell input without a “None” option descriptor selected. A selected configuration - cell arrangement - code informs the 7955 of the cell inputs to read and processed.

B Table 11.9.1 shows a selection of configuration codes (option descriptors) for the more likely ‘pay’ and ‘check’

cell arrangements. Other combinations involving 5 cells can be selected.

Table 11.9.1: Selection Codes, Cell Arrangements and Pressure Range Switching

Configuration Code Cell Arrangement Range Selection?

H=DP:1 ‘Pay’ Cell #1 - always the primary - covers a high pressure range. No

H=DP:12 ‘Pay’ Cell #1 and ‘Check’ Cell #2 cover exactly the same high range. No

H=DP:1 L=DP:2 ‘Pay’ Cell #1 covers the high range. ‘Pay’ Cell #2 covers the low range. Yes

H=DP:12 L=DP:3 Cell #1 (‘Pay’) and Cell #2 (‘Check’) cover exactly the same high range. Cell #3 (‘Pay’) covers the low pressure range. Yes

H=DP1 M=DP2 L=DP3 Cell #1 (‘Pay’) used for high pressure range. Cell #2 (‘Pay’) used for medium range. Cell #3 (‘Pay’) used for low pressure range. Yes

H=DP:12 L=DP:34 Cells #1 (‘Pay’) and #2 (‘Check’) cover the high pressure range. Cells #3 (‘Pay’) and #4 (‘Check’) cover the low pressure range. Yes

H=DP:1p23 L=DP:4p5 Cells #1 (‘Pay’), #2 (‘Check’) and #3 (‘Check’) cover the high range. Cells #4 (‘Pay’) and #5 (‘Check’) cover the low pressure range. Yes

C ‘LO switch’ is a low point marker in terms of a percentage 4 of the presently selected pressure range.

A 7955 calculated DP value, resulting from this ‘Set’ percentage, is the boundary at which primary use of a ‘pay’ DP Cell is automatically switched to another ‘pay’ DP Cell with a lower range. This switch will provide measurements that are more accurate.

‘HI Switch’ is a high point marker in terms of a percentage of the presently selected pressure range.

A 7955 calculated DP value, resulting from this ‘Set’ percentage, is the boundary at which primary use of a ‘pay’ DP Cell is automatically switched to another ‘pay’ DP Cell with a higher range. This switch will provide measurements that are more accurate.

D Optional feature: ‘Calibration error’ (i.e. limit) Checks.

• <“Diff press cal error“> is the alarm limit for the maximum difference in differential pressure measurements between a selected (prime) DP Cell and the next suitable (prime) DP Cell. An alarm is raised if the limit is exceeded for longer than a period as ‘Set’ by <“Diff press cal time”>. (Not enabled when limit is ‘Set’ to 0).

E Deviation refers to difference in differential pressure measurements between ‘Master’ (or ‘Pay’) DP Cell and any

‘Check’ DP Cells. F Automatic selection of a ‘higher’ range DP Cell can cause a mA input failure alarm to be raised even though the

transmitter has not actually failed. The cause of this alarm is the mA signal from a ‘lower’ range cell exceeding 111% of the 20mA analogue input range as the cell continues to measure beyond it’s effective range. This alarm condition remains until the lower range cell is re-selected.

<“DP inputs alarm”> gives the option of suppressing the alarm under this particular situation. By default, there is no suppression.

G Identifies the range - low, medium or high - of the selected primary ‘pay’ DP Cell. (Read-only data value). H The “Reynolds Number” calculation is iterative and requires a previous value for the mass flow rate. This is the

reason for showing the mass rate by an Orifice calculation block.

4 Alternative units, such as particles per million, may be shown on-screen.


7955 2540 (CH011/AF) Page 11.21

ORIFICE FLOW METERING (ISO 5167-1/AGA3/HART)

Notes continued…

I The <“Flow status”> menu data page is located within the INFORMATION soft-key menu. It shows if the Flow Computer considers there to be either normal flow (“flowing”) or zero flow at up to four metering-points.

Flow stop (zero flow) threshold parameters, such as <“DP flow stop limit”>, are used to force ‘LIVE’ flow rates to 0 and therefore halt flow totalising, even when there is negligible flow. (<“Flow status”> = “Flow stopped”)

However, negligible flow rate values may still be calculated, for display purposes only, if enabled by the <“Rate flowstop actions”> menu data. Calculations using flow rate inputs will still get 0 values.

In the case of an Orifice Metering System, normal flow is acknowledged whenever the δP value is greater than the programmed value for <“DP flow stop limit”>. (<“Flow status”> = “Flowing”)

J Support for the use of other primary DP devices is made possible with the ability to ‘Set’ values for the Velocity

of approach and the Discharge coefficient. For this software feature, these values can be ‘SET’ to a known value only by using the “Flow Meter” Wizard.

K The liquid expansibility factor has a fixed value of 1. L See “Viscosity” reference pages, on either page 11.60 or page 11.62


Page 11.22 7955 2540 (CH011/AF)

ORIFICE PLATE/VENTURI EQUATIONS

Equation List: The equations that follow are common to both ISO 5167-1:1991, ISO 5167-1:1991/Amd:1998 and AGA 3 standards unless otherwise stated. Refer to the appropriate Standard for information on any restrictions not listed here.

Support for the use of other primary DP devices is made possible with the ability to ‘Set’ values for the Velocity of approach and the Discharge coefficient. For this software feature, these values can be ‘Set’ to a known value only by using the “Flow Meter” Wizard.

Equation OR#1: Mass flow rate

The mass flow rate is related to differential pressure by the following equation:

Using: mQ = 3600**1000

* ⎟⎠

⎞⎜⎝

⎛ ρδPK

Where: mQ = Mass flow rate (in Kg/hour)...……….............................. {Menu Data: <“Mass rate”>}

K = Mass flow rate ‘K’ factor............…..……….................... {See Equation OR#2}

Pδ = Differential pressure measurement (in mbar)…….….... {Menu Data: <“Diff press value”>}

ρ = Density of measured fluid.........................……….......... {Menu Data: <“Meter run density”>}

Equation OR#2: Mass flow rate ‘K’ factor

Using: K = 12 **** NdEC ε

Where: K = Mass flow rate ‘K’ factor.................……….................... {Menu Data: <“Orif mass k factor”>}

C = Discharge coefficient..........................………................ {See equations OR#9a to OR#9d}

E = Velocity of approach factor.......................…….…......... {See Equation OR#5}

ε = Liquid expansibility factor = 1...................……….......... {Menu Data: <”Orif expandability”>}

'd = Orifice diameter, corrected for expansion.....………..... {See Equation OR#3a}

N1 = 1000*10*4

2* 5−π = 0.0003512407367 ……….. {Actual constant used}

π = 3.141592654.........................................………............. {Actual constant used}

Equation OR#3: Correction for area expansion of the orifice and pipe

Using: 'd = ( )[ ]610**1* −−+ oc Ettd …………….……………..…. OR#3a

Where: d ' = Orifice diameter, corrected for expansion……….......... {Menu Data: <“Orif corr pipe dia”>}

d = Orifice diameter at calibration temperature ‘tc’……….... {Menu Data: <“Corr orif diameter”}

t = Temperature at the metering-run..................………..... {Menu Data: <“MeteRun temperature”>}

tc = Orifice calibration temperature....................………....... {Menu Data: <“Orifice cal temp”>}

Eo = Orifice expansion coefficient.......................………....... {Menu Data: <“Orif expans coeff”>

Using: 'D = ( )[ ]610**1* −−+ Pc EttD ………………………..…….. OR#3b

Where: 'D = Pipe diameter, corrected for expansion........……..….... {Menu Data: <“Orif corr pipe dia”>}

D = Pipe diameter at calibration temperature ‘toc’..….……... {Menu Data: <“Orifice diameter”>}

t = Temperature at the metering-run.................……..…..... {Menu Data: <“MeteRun temperature”>}

ct = Orifice plate calibration temperature...........………........ {Menu Data: <“Orifice cal temp”>}

PE = Pipe expansion coefficient.........………......................... {Menu Data: <“Pipe expans coeff”>}


7955 2540 (CH011/AF) Page 11.23

ORIFICE PLATE/VENTURI EQUATIONS (Equation List continued…)

Equation OR#4: Diameter ratio

Uses: β = '

'

Dd

Where: β = Beta ratio (no units)…………………….………………. {Menu Data: <“Orifice beta”>}

'd = Orifice diameter, corrected for expansion………........ {Menu Data: <“Corr orif diameter”>}

'D = Pipe diameter, corrected for expansion......…….….... {Menu Data: <“Orif corr pipe dia”>}

Equation OR#5: Velocity of approach factor

Using: E = ( ) 2

141

−− β

Where: E = Velocity of approach factor..............…………............. {Menu Data: <“Orif vel of approach”>}

β = Diameter ratio........................................…………....... {See Equation OR#4}

Equation OR#6a: (ISO 5167) Reynolds number for discharge coefficient

Using: edR = ⎟⎟⎠

⎞⎜⎜⎝

⎛⎟⎟⎠

⎞⎜⎜⎝

⎛μπ '**

10*4*

3600

6

DQm

Where: edR = Reynolds number............………….......................... {Menu Data: <“Reynolds number”>}

mQ = Mass flow rate from previous cycle….…................. {See Equation OR#1}

π = 3.141592654...................................………….......... {Actual constant used}

'D = Pipe diameter (corrected for expansion)………....... {See Equation OR#3b}

μ = Dynamic viscosity................………......................... {Menu Data: <“Meter dynamic visc”>}

Equation OR#6b: (AGA3) Reynolds number for discharge coefficient

Using: edR = ⎟⎟⎠

⎞⎜⎜⎝

⎛⎟⎟⎠

⎞⎜⎜⎝

⎛μ'*

10*4*

3600*

6

2 DQ

N m

Where: edR = Reynolds number....................………...................... {Menu Data: <“Reynolds number”>}

2N = 1273239.5.....................................………................ {Actual constant used}

mQ = Mass flow rate from previous cycle…...................... {See Equation OR#1}

D' = Pipe diameter (corrected for expansion)………....... {See Equation OR#3b}

μ = Dynamic viscosity...................................………...... {Menu Data: <“Meter dynamic visc”}

Equation OR#7a: STOLZ (ISO 5167-1:1991) Discharge coefficient for Orifice Plate

• Basic Equation Component

Use: 1C =

75.065.281.2 10

**0029.0*184.0*312.05959.0 ⎟⎟⎠

⎞⎜⎜⎝

⎛+−+

edRβββ

Where: 1C = Basic equation component

β = Diameter ratio......................…………......................... {See Equation OR#4}

Red = Reynolds number.............................………................ {See Equation OR#6a}


Page 11.24 7955 2540 (CH011/AF)

ORIFICE PLATE/VENTURI EQUATIONS (Equation List continued…)

• For Corner Tappings only

Use: C = 1C

Where: C = Discharge coefficient...................……….................... {Menu Data: <“Orif discharge coeff”>}

1C = The basic equation component........………............... {See above}

• For D and D/2 tappings only

Use: C = ( ) ( ) ( )31441 *015839.01**039.0 βββ −−+

−C

Where: C = Discharge coefficient...........………......................... {Menu Data: <“Orif discharge coeff”>}

1C = Basic equation component...........………................ {See above}

β = Diameter ratio...................………............................ {See Equation OR#4}

• For Flange Tappings where the pipe diameter (corrected for expansion) is larger than 58.62mm

Use: C = ( ) ( ) ⎟⎠

⎞⎜⎝

⎛−−+− 3144

1 *'

85598.01**039.0 βββ

DC

Where: C = Discharge coefficient..................……….................. {Menu Data: <“Orif discharge coeff”>}

C1 = Basic equation component.............………............... {See above}

β = Diameter ratio..............................………................. {See Equation OR#4}

'D = Pipe diameter (corrected for expansion)..…..……... {See Equation OR#3b}

• For Flange Tappings where the pipe diameter (corrected for expansion) is less than or equal to 58.62mm

Use: C = ( ) ⎟⎠

⎞⎜⎝

⎛−−⎟⎠

⎞⎜⎝

⎛+− 3144

1 *'

85598.01**

'

286.2 βββDD

C

Where: C = Discharge coefficient.....……….................................. {Menu Data: <“Orif discharge coeff”}

1C = Basic equation component.......………....................... {See above}

β = Diameter ratio.................................……....…….......... {See Equation OR#4}

D' = Pipe diameter (corrected for expansion)……..…....... {See Equation OR#3b}

Equation OR#7b: (ISO 5167-1:1991) Discharge coefficient for a Venturi tube

C = 0.984 when there is an ‘as cast’ convergent section where: -

100mm ≤ D ≥ 800mm 0.3 ≤ β ≥ 0.75 2 * 105 ≤ Red ≥ 2 * 106

C= 0.995 when there is a machined convergent section where: -

50mm ≤ D ≥ 250mm 0.4 ≤ β ≥ 0.75 2 * 105 ≤ Red ≥ 1 * 106

C=0.985 when there is a rough welded sheet iron convergent section where:-

200mm ≤ D ≥ 1200mm 0.4 ≤ β ≥ 0.7 2 * 105 ≤ Red ≥ 1 * 106


7955 2540 (CH011/AF) Page 11.25

ORIFICE PLATE/VENTURI EQUATIONS

Equation OR#7c: (AGA3) Discharge coefficient for an Orifice Plate

Refer to part 4 of AGA report 3 (November 1992, Third edition) for details of the Reader-Harris/Gallagher equation.

Equation OR#7d: (ISO 5167-1:1998) Discharge coefficient for an Orifice Plate

Equation Terms and Menu Data:

C = Discharge coefficient……………………………………...………… {Menu Data: <“Orif discharge coeff”>}

D' = Pipe diameter (corrected for expansion).....……………….……... {See Equation OR#3b}

β = Diameter ratio....................……………………............................. {See Equation OR#4}

Red = Reynolds number..........................……………………................. {See Equation OR#7a}

Refer to section 8.3.2.1 of the ISO 5167-1:1991(E)/Amd.1:1998(E) Standard for details of the Reader-Harris/Gallagher equation.

Equation OR#8: Pressure ratio

Use: PR = 1

2

PP

Where: PR = Pressure ratio...............................…………............... {Menu Data: <“Pressure ratio”>

1P = Pressure at up-stream tapping (in Bar)...…..……...... {No Menu Data}

= ( )310* −+ LossPP

2P = Pressure at down-stream tapping (in Bar).……...…... {No Menu Data}

=P P1 − δ

And: P = Pressure measured at the metering-run……...…....... {Menu Data: <“Mete run pressure”>}

LossP = Pressure loss (in Bar)..........………..…...................... {Menu Data: <“Pressure loss”>}

= ( )( )βδ *25.13.1* −P

Equation OR9: Gross Volume flow rate

Use: GVQ =⎟⎟⎟

⎠

⎞

⎜⎜⎜

⎝

⎛

Meter

mQ

ρ

Where: GVQ = Gross Volume flow rate..………………………………. {Menu Data: <”Gross vol rate”>}

mQ = Mass flow rate…………………………..………………. {Menu Data: <”Mass rate”>}

Meterρ = Metering density……………………………...…………. {Menu Data: <”Meter run density”>}


Page 11.26 7955 2540 (CH011/AF)

ORIFICE V-CONE EQUATIONS

Listed equations OVC#1 to OVC#5 are formulated from the standard flow equations as published by McCrometer, the V-Cone manufacturer. The remaining equations (OVC#6 to OVC#9) are provided for completeness and comply with the ISO 5167-1:1991 and ISO 5167-1:1991/Amd:1998 Standards.

Equation OVC#1: Mass flow rate

The mass flow rate is related to differential pressure by the following equation:

Using: mQ = ( ) afc FCPDg *3600****1

****2*

4 4

22

εδβ

βρπ⎟⎟⎟

⎠

⎞

⎜⎜⎜

⎝

⎛

−

Where: Qm = Mass flow rate (in Kg/hour)............……......……........... {Menu Data: <“Mass rate”>}

cg = Dimensional conversion constant = 1…….………...….. {Actual constant used}

ρ = Density of measured fluid (in Kg/m3).........………..........{Menu Data: <“Meter run density”>}

D = Cone inner diameter (in metres), uncorrected…..…….. {Menu Data: <“Pipe diameter”>}

β = Meter beta (diameter) ratio (no units)……...………..… {See Equation OVC#4b}

δP = Differential pressure measurement (in Pa)…….…….... {Menu Data: <“Diff press value”>}

fC = Flow coefficient of the meter (no units)…………...……. {Menu Data: <“Orif discharge coeff”>}

ε = Liquid expansibility factor = 1 (no units)…......……....... {Actual constant used}

aF = Meter thermal expansion factor…………………...…….. {See Equation OVC#2}

Note: The flow coefficient is not calculated when using a V-Cone meter. It is necessary to locate Cf on the calibration certificate and then ‘Set’ a value.

Equation OVC#2: Thermal expansion factor (Fa)

If the material expansion coefficients of the pipe and the cone are the same…

Use: aF = ( )( )528**21 −+ tPEα ……………….……….……..……. OVC#2a

Where: aF = Meter thermal expansion factor………..…….………….. {No Menu Data}

PEα = Coefficient for thermal expansion per degree Rankine. {No Menu Data}

t = Operating temperature (in degrees Rankine)….……… {Menu Data: <”MeteRun temperature”>}

If the material expansion coefficients of the pipe and the cone are not the same…

Use: aF = ( )( )

( )( )22

2

14

2

14

22

*

1*

'1

'*'

ββ

β

βD

D −

−

……………..…………………….. OVC#2b

Where: Fa = Meter thermal expansion factor………..………...……… {No Menu Data}

'D = Cone inner diameter, corrected for expansion……..…. {See Equation OVC#4a}

D = Cone inner diameter (in metres), uncorrected…..…….. {Menu Data: <“Pipe diameter”>}

'β = Beta ratio, corrected dimensions (no units)…….……… {See Equation OVC#3a}

β = Beta ratio, uncorrected dimensions (no units)…...….… {See Equation OVC#3b}

Equation OVC#3: Beta Ratio

Use: 'β = 2

1

2

2

'

'1

⎥⎥⎦

⎤

⎢⎢⎣

⎡⎟⎟⎠

⎞⎜⎜⎝

⎛−

Dd

………………….………..………………….. OVC#3a

Where: 'β = Meter beta ratio (no units)………….….……….………... {Menu Data: <“Orifice beta”>}

'd = Cone outside diameter, corrected for expansion…...…{See Equation OVC#4b}

'D = Cone inner diameter, corrected for expansion……..….{See Equation OVC#4a}


7955 2540 (CH011/AF) Page 11.27


(Equation OVC#3: Beta Ratio)

Use: β = 2

1

2

2

1⎥⎥⎦

⎤

⎢⎢⎣

⎡⎟⎟⎠

⎞⎜⎜⎝

⎛−

Dd

………………………………..……....………OVC#3b

Where: β = Meter beta ratio (no units)……….…………….……….... {No Menu Data}

d = Cone outside diameter, uncorrected for expansion…..{Menu Data: <“Orifice diameter”>}

D = Cone inner diameter, uncorrected for expansion……..{Menu Data: <“Pipe diameter”>}

Equation OVC#4: Corrections for thermal expansion of V-Cone

If the expansion coefficients of the pipe and the cone are not the same…

Use: 'D = ( )( )cttDD −+ ** α ……………………..………….…….. OVC#4a

Where: 'D = Cone inner diameter, corrected for expansion……....… {Menu Data: <“Orif corr pipe dia”>}

D = Cone inner diameter (in metres), uncorrected……..….. {Menu Data: <“Pipe diameter”>}


t = Operating temperature (in degrees Rankine)………….. {Menu Data: <”MeteRun temperature”>}

tc = Calibration temperature (in degrees Rankine)..………. {Menu Data: <”Orifice cal temp”>}

Use: 'd = ( )( )cttdd −+ **α ………………………..………...…….. OVC#4b

Where: 'd = Cone outer diameter, corrected for expansion….…..… {Menu Data: <“Corr orif diameter”>}

d = Cone outer diameter (in metres), uncorrected……..….. {Menu Data: <“Orifice diameter”>}


t = Operating temperature(in degrees Rankine)……….….. {Menu Data: <”MeteRun temperature”>}

tc = Calibration temperature (in degrees Rankine)…..……. {Menu Data: <”Orifice cal temp”>}

Equation OVC#5: Velocity of approach

Use: E = ⎟⎟⎠

⎞⎜⎜⎝

⎛2*

*4

DQV

π

Where: E = Velocity of approach factor………………….….……… {Menu Data: <”Orif vel of approach”>}

D = Cone inner diameter, uncorrected for expansion..…. {Menu Data: <“Pipe diameter”>}

And: VQ = 3600*⎟⎟⎠

⎞⎜⎜⎝

⎛ρmQ

Where: VQ = Volume rate (in m3/second)……………………………. {No Menu Data}

mQ = Mass flow rate (in Kg/hour)……………………………. {See Equation OVC#1}

ρ = Density of measured fluid (in Kg/m3).........…...…........{Menu Data: <“Meter run density”>}

Equation OVC#6: Reynolds number

Use: edR = ( )

μρ** ED

Where: edR = Reynolds number……………………………………….. {Menu Data: <”Reynolds number”>}

E = Velocity of approach factor………………………..…… {See Equation OVC#5}

D = Cone inner diameter, uncorrected for expansion..…. {Menu Data: <“Pipe diameter”>}

μ = Dynamic viscosity………………………………………. {Menu Data: <”Meter dynamic visc”>}


Page 11.28 7955 2540 (CH011/AF)


Equation OVC#7: Pressure ratio

Use: PR = 1

2

PP

Where: PR = Pressure ratio...............................…………............... {Menu Data: <“Pressure ratio”>

1P = Pressure at up-stream tapping (in Bar)...…..……...... {No Menu Data}

= ( )310* −+ LossPP

2P = Pressure at down-stream tapping (in Bar).……...…... {No Menu Data}

= PP δ−1

And: P = Pressure measured at the metering-run……...…....... {Menu Data: <“Mete run pressure”>}

LossP = Pressure loss (in Bar)..........………..…...................... {Menu Data: <“Pressure loss”>}

= ( )( )βδ *25.13.1* −P

Equation OVC#8: Mass rate ‘K factor’

Using: K = ( )ρδ *PQm

Where: K = Mass flow rate ‘K’ factor........................…...……....... {Menu Data: <“Mass rate k factor”>}

mQ = Mass flow rate (in Kg/hour)............……...…............... {Menu Data: <“Mass rate”>}

Pδ = Differential pressure (in Bar).......………….………..... {Menu Data: <“Diff pressure value”>}

ρ = Density of measured fluid (in Kg/m3).......………........ {Menu Data: <“Meter run density”>}

Equation OR9: Gross Volume flow rate

Using: GVQ =⎟⎟⎟

⎠

⎞

⎜⎜⎜

⎝

⎛

Meter

mQ

ρ

Where: GVQ = Gross Volume flow rate..………………………………..{Menu Data: <”Gross vol rate”>}

mQ = Mass flow rate…………………………..………………. {Menu Data: <”Mass rate”>}

Meterρ = Metering density……………………………...…………. {Menu Data: <”Meter run density”>}


7955 2540 (CH011/AF) Page 11.29

11.10 CORIOLIS FLOW METERING

Measurements Supported: • Mass flow rate - direct from up to four Coriolis mass flowmeters • Gross Volume flow rate – at up to four metering-points • Gross Standard Volume flow rate - at up to four metering-points

8

7

6

MASSRATEQm

GROSSVOLUME

RATE39ρMeter

HI

LOQm

42

41

40HI

LO

QGV

GROSSSTANDARD VOLUME

RATE

45

44

43HI

LO

QSGV

39

47

FLOWTOTALLING

FLOWTOTALLIN

G

FLOWTOTALLING


ρMeter

ρBase

Qm

46CCF

(mA)Live InputSelection

2

mA Inputs

HART InputsMass Rate(Scaling)

%

Qm(HART Route)

3 4 5

ApplyFactor

0% 100%

Qm

11 fPULSE

FREQUENCY(from a Pulse Input)

12

9

10

HI

fIndicatedMass RateCalculation

"Correction"route

"Conversion"route

K FactorCalculatio

n34

331413

f


GrossMass RateCalculation


35

331413

GrossMass RateCalculation

Kf

CalibrationCertificate

MF Qm

IndicatedMass RateCalculation

35

38

MF

QIM

38QIM

Qm

34Kf

48

OR

f

1

OR

FlowStop

36

37

36

37LO

HI

HI

LO

48

48

48

Menu Navigation List: (1) <“Configure”>/<”Inputs”>/<“Flow meter”>/<”Flow meter type”>, (2) <“Configure”>/<”Inputs”>/<“Flow meter”>/<”Coriolis details”>, (3) <“Configure”>/<“Flow rate”>, (4) <”Flow rates”> (5) <“Density”>/<”Meter density”> and (6) <”Base density / SG”>/<”Base density”> Menu Data List: * shows data that can be “Live” or “Set”


- Flow meter type 24 Error% / Kfactor 1

1 Mass rate input type E, : : : :

2 Mass rate HART chl A, 33 Error% / Kfactor 10

3 Mass rate 0% value 34 Flowmeter K factor *

4 Mass rate 100% value 35 Meter Factor *

5 HART mass rate fact B, 36 Ind Mass Rate HI lmt C,

6 Mass rate HI limit C, 37 Ind Mass Rate LO lmt C,

7 Mass rate LO limit C, 38 Indicated mass rate

8 Mass rate * 39 Meter run density *

9 Meter freq HI limit 40 Gross vol HI lmt C,

10 Flow stop threshold 41 Gross vol LO lmt C,

11 Meter freq * 42 Gross vol rate *

12 Meter curve type G 43 Gross std vol HI lmt C,

13 Meter curve points 44 Gross std vol LO lmt C,

14 Flow/freq 1 45 Gross std vol rate *

: : 46 Combined cor factor * D

23 Flow/freq 10 47 Base density * (D)

48 Flow rate action F

Notes are listed on the next page

Note:When a Coriolis meter is configured to output a frequency representing volume rather than mass, you must use the Turbine/PD Flow metering support.


Page 11.30 7955 2540 (CH011/AF)

CORIOLIS FLOW METERING CONFIGURATION REFERENCE

Notes: Separate location value (and state) for each of four metering-points but all accessible through same menu

page. Use the appropriate SELECTION key to cycle between metering-points A Ensure that the basic configuration information of the live input channel has been completed.

Analogue Input…..….…… Turn to reference page 11.6 HART Input……….………. Turn to Chapter 17

B This factor location is for converting the Flow Computer scaled mass rate value into units of Kg per hour.

By default, the factor has a value of 1.00; this setting assumes that the flowmeter converted the measured mass rate from units of Kg per hour into a mA value.

C Optional HI and LO alarm limits. Programming the limits with a zero value will avoid maximum and minimum

alarm limit checks on the associated measurement. D See “Volume Correction Factor” references in the Equation List section. [MENU(3)] E A Coriolis mass flow meter is a resonating tube device that will distort proportionately to the rate of fluid

mass flowing through it. The relationship of mass flow to the distortion for the meter is characterised to produce a k-factor in pulse/mass or mass/pulse units.

The signal output will generally be in the form of a pulse frequency signal, although a current 4-20mA output may also be available.

The Coriolis meter may also be configured to output a signal representative of volume. In this case the flow computer will handle the meter signal output in the same way as a single pulse input turbine signal. Unlike turbine signals ‘error checking’, (IP252), will not be carried out on the mass flow input signal. However, similar to the turbine linearisation, the flow computer allows the user to define a mass flow linearisation curve across a flow range. The curve will define the error deviation against flow or K-factor against frequency in terms of mass units. The linearisation calculation will automatically account for mass or volume type units based on the meter type selected by the user during configuration.

F By default, the 7955 calculates, for display purposes only, the actual live flow rates under a ‘Flow stopped’

condition, even when there is negligible flow. However, display can be forced to show zero flow by selecting the multiple-choice option with “Zero flow rates”.

(Calculations using a flow rate will always use a zero value during a “Flow Stop” condition) G There are two calibration curve options supported:

(1) “Conversion K v Hz”

A ‘K-factor’ is interpolated, once during every machine cycle, from a user-programmable calibration curve. The ‘Meter factor’ (MF) is a fixed (SET) value. A SET MF value can still be updated by a proving session, by product detection, or by a MODBUS networked device. Also, see Figure 11.8-1 on page 11.12.

(2) “Correction% v flow” (Default Option)

The ‘Meter Factor’ (MF) is calculated, once during every machine cycle, by a relative error (percentage) correction process. The ‘K-factor’ is a fixed (SET) value. They may then be updated by a proving session, by product detection or by a MODBUS networked device. Also, see page 11.12.

Proving sessions can overwrite either a ‘Meter Factor’ value or the ‘K-factor’ value. It is dependent on how proving is configured and if the prove session is successful. (See Chapter 16 and 16A)

Product detection can also overwrite a ‘Meter Factor’ (MF) value and/or the ‘K-factor’ value.


7955 2540 (CH011/AF) Page 11.31

EQUATION LIST CORIOLIS FLOW METERING Equation List:

Equation CFM#1: Gross Volume flow rate

Using: QGV =⎟⎟⎟

⎠

⎞

⎜⎜⎜

⎝

⎛

Meter

mQ

ρ

Where: QGV = Gross Volume flow rate…….……….…….….. {Menu Data: <”Gross vol rate”>}

Qm = Mass flow rate……………………...……..……. {Menu Data: <”Mass rate”>}

Meterρ = Metering density………………...………..……. {Menu Data: <”Meter run density”>}

Equation CFM#2: Gross Standard Volume

Using: QGSV = ( )CCFQGV *

Where: QGSV = Gross Standard Volume flow rate...………….. {Menu Data: <”Gross std vol rate”>}

QGV = Gross Volume flow rate..…………………..….. {See Equation CFM#1}

CCF = Combined Correction Factor…………….…..... {See Equation CFM#3}

Equation CFM#3: Combined Correction Factor

The equation used is dependent on the selected method for density referral - API Standard or 4x5 Matrix

Using: CCF = MFCPLCTL ** ……………..……….………….. (API)

Or: CCF = ⎟⎟⎠

⎞⎜⎜⎝

⎛MF

B*

ρρ .......………………………..……… (4x5)

Where: CCF = Combined correction factor………..…..….……. {Menu Data: <”Combined cor factor”>}

CTL = API temperature correction factor……......……. {Menu Data: <”CTL”>}

CPL = API pressure correction factor……..…..………. {Menu Data: <”CPL”>}

MF = Meter Factor……………………………....………. {Menu Data: <”Meter factor”>}

And: ρ = Fluid density at a metering-point…….…..…...… {Menu Data: <”Meter run density”>}



Page 11.32 7955 2540 (CH011/AF)

11.11 TOTALISING (BY METERING-POINT)

7955 totalling features 3 basic types of incremental, roll-over counter:

Flow Total............... 5 x flow rate based totals for each metering-point. Each total is enabled by configuring the associated meter-run flow rate.

Alarm Total……...… 1 x user total for each metering-point. This is for totalling of either a flow rate or missing

pulses from a dual pickup flowmeter. It increments only when there is an ‘active’ alarm. Error Pulse Total…. 1 x error pulse total for each metering-point. This is for totalling of missing pulses from a

dual pickup flowmeter. This totaliser function is permanently enabled. Further separation of a total is made by the Flow Computer mode:

• Normal-mode (Standard) total This total is frozen whilst 7955 is in ‘Maintenance-mode’.

• Maintenance-mode total This total is frozen whilst 7955 is in ‘Normal-mode’.

Every metering-point can have a different Flow Computer mode selected. (Menu Data: <“Operating mode”>) Menu Navigation List: (1) <“Configure”>/<“Totalisation”>/<”Standard…”> (2) <”Flow rates”>/<“MeterRun flowrates”> (3) <“Flow totals”>/<”Meter run totals”> (4) <“Health check”>/<“Totals”> (5) INFORMATION (‘i’-key) Menu Menu Data Lists: * shows data that can be “Live” or “Set”

Indx Menu data (as displayed)

Menu data (as displayed)



Menu data (as displayed) Notes?

1 Indicated vol rate * Gross vol rate * Ind std vol rate Gross std vol rate * Mass rate * , A

2 Ind volume total Gross vol total Ind std vol total Gross std vol total Mass total , A

3 Ind vol increment Gross vol increment Ind std vol inc Gross std vol inc Mass increment ,D

4 Ind vol rollover Gross vol rollover Ind std vol roll Gross std vol roll Mass rollover E

5 Ind vol inhibit Gross vol inhibit Ind std vol inhibit Gross std vol inhib Mass inhibit C

6 Maint IV total Maint GV total Maint ISV total Maint GSV total Maint Mass total

7 Maint IV increment Maint GV increment Maint ISV increment Maint GSV increme.. Maint Mass increm... ,D

= Separate location value (and state) for each of four metering-points

Note: Configure totalling for individual metering-points before progressing to station totalling

Index Menu data (as displayed) Notes? Index Menu data (as displayed) Notes?

8 Alarm total source , C 14 Flowmeter error inc , D

9 Alarm increment , D 15 Flowmeter error roll E

10 Alarm total , C 16 Maint meter error

11 Alarm rollover C, E 17 Maint meter err inc , D

12 Meter error pulses , B 18 Operating mode , F

13 Flowmeter errors , B

- Flow status , F

= Separate location value (and state) for each supported metering-point

Figure 11.11-1: Totaliser Blocks and Parameters

6

1

Flow Totaliser(Normal Mode)

3 5

FLOWRATE

FLOWTOTAL

Flow Totaliser(Maintenance)

7

4

18

+ Mode

2

Index for use withlisted menu data

XX

15

12

Totaliser(Normal Mode)

ERRORPULSECOUNT Totaliser

(Maintenance)

16

18

Mode

13ERRORPULSETOTAL

Totaliser(Maintenance)

10

ALARMTOTAL

SelectionPulse

Outputs

8 9 11

14


7955 2540 (CH011/AF) Page 11.33

CONFIGURATION REFERENCE TOTALISING (BY METERING-RUN)

Notes:

A Indicated Volume measurements are not available in an Orifice system. B Missing (error) pulses are detectable when using a dual pickup pulse train configuration. C Alarm condition totalling operates independently of all other totalling. A flow total can be frozen under alarm

conditions when enabled by the corresponding ‘inhibit’ menu data. D An increment value is calculated by integrating a parameter value, e.g. flow rate, over time. The result is added

to a corresponding total once during every machine cycle. (a) Orifice or Coriolis Flow

The time element of the increment calculation is the ‘actual cycle time’. This value is the elapsed time between a flow measurement. It is available for viewing from within the <“Time”> menu.

(b) Turbine Flow

The time element of the increment calculation is the ‘pulse sample time’. It is the period of time that pulses were accumulated for use in calculating the present value of the Indicated Volume flow rate. This time value is available for viewing within the <”Health check”> feature menu.

Editing an increment value has no effect. E By default, rollover (to zero) limits are ‘Set’ to a large number. However, it is advisable to check that the limit is

sufficient for the metering application. F There are two Flow Computer modes to be aware of:

1. Normal-mode In this mode, a standard total (e.g. “Ind volume total”) can increment. The corresponding maintenance-mode total (e.g. “Maint IV total”) will never increment.

2. Maintenance-mode In this mode, a maintenance-mode total can increment. The corresponding standard total will never increment.

A mode can be selected for each metering-point. However, the selection can only be performed when the 7955 is in a ‘Flow Stopped’ state for the metering-point concerned.

For information on how the 7955 can be in a ‘Flow Stopped’ state, refer to the <”Flow status”> menu data notice (with the menu data list) on the Flow Metering pages:

Turbine Flow.….. Page 11.10

Orifice Flow…..... Page 11.17

Coriolis Flow.….. Page 11.29


Page 11.34 7955 2540 (CH011/AF)

11.12 TOTALISING (BY STATION)

7955 totalling features 3 basic types of incremental, roll-over counter:

Flow Total............... 5 x Station flow rate based totals (excluding net oil/water totalising, which is described later) Each total is enabled by configuring the associated flow rate for at least one metering-point.

Alarm Total……...… 1 x user total for all metering-points.

This is for totalling of either a station flow rate or missing pulses from all dual pickup flowmeters. It can increment only when there is an ‘active’ alarm.

Error Pulse Total…. 1 x error pulse total for all metering-points.

This is for totalling of missing pulses from all dual pickup flowmeters. This totaliser function is permanently enabled.

Figure 11.12-1: Station Totalising Blocks and Parameters

2 Station Totaliser(Forward Flow)

STATIONFLOWRATE FORWARD FLOW

STATION TOTAL+ 3

4Pulse

Outputs

Index for use with listed menu dataXX

1 Add/SubMetering-point

FLOWRATES

6 5

Menu Navigation List: (1) <“Configure”>/<“Totalisation”>, (2) <“Flow totals”>, (3) <“Health check”>/<“Totals”> and (4) INFORMATION (‘i’ soft-key) Menu Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data

(as displayed) Menu Data




(as displayed) Notes?

1 Ind vol rate * Gross vol rate * Ind std vol rate * Gross std vol rate * Mass rate * , A

2 Stn ind vol rate * Stn gross vol rate * Ind std vol rate * Stn gro std vol rate * Stn mass rate *

3 Stn ind vol total Stn gross vol total Stn ind std vol totl Stn gros std vol tot Stn mass total D, E

4 Stn ind vol roll Stn gross vol roll Stn ind std vol roll Stn gross vol roll Stn mass roll C

5 Stn ind vol inhib Stn gross vol inhib Stn ind std vol inh Stn gros std vol inh Stn mass inhib

6 Station totalise B,

= Separate location value (and state) for each of four metering-points

Notes: A Indicated Volume measurements are not available in an Orifice system.

B By default, rate values from all individual metering-points are added together to get the station value. This summation process can be changed for all station totals, with immediate effect, by selecting an appropriate soft-command (option descriptor) through the <”Station totalise”> menu data page. Always check the metering-point ID on line 4 before making changes

C By default, rollover (to zero) limits are ‘SET’ to a large number. However, it is advisable to check that the limit is

sufficient for the metering application. D A Station total is a normal-mode total. There is no equivalent maintenance-mode total. Increments for a

Station total only involve ‘metering-points’ that are not operating in maintenance-mode. E At present calculated increments (for station totals) are not displayed within the menu system.


7955 2540 (CH011/AF) Page 11.35

11.13 HEADER ‘DENSITY’ TEMPERATURE (1X4X1 SCHEME)

Measurements Supported: (Also, see page 11.46 for use of prime selected Header density)

• ‘Density loop’ fluid temperature ‘A’ - at the Header • ‘Density loop’ fluid temperature ‘B’ - at the Header • Prime selected Header ‘density loop’ fluid temperature

Figure 11.13-1: Header Temperature Blocks and Parameters (1x4x1 Scheme)

mALive InputSelection

10

1mA inputs

HART inputs

PT100 inputs

TemperatureCalculation(Scaling)

PT100 or HART

2 3


20

11mA inputs

HART inputs

PT100 inputs


PT100 or HART

12 13

HeaderSelection

22

21

DENSITYTEMPERATURE 'A'

DENSITYTEMPERATURE 'B'

HEADER (DENSITY)TEMPERATURE

23

ApplyOffset

9

Fallback andLimits Check

4 5 6

7 8

ApplyOffset

19


14 15 16

17 18

Menu Navigation List: (1) <“Configure”>/<“Temperature”>/<“Densitometer temp”>, (2) <“Temperature”>/<“Dens temperature”>, (3) <“Configure”>/<“Density”>/<”Header dens”> and (4) <”Configure”>/<”Transducer details”>/<”Flow system type”> Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 1 Dens tempA source A 13 Dens tempB @ 0/4mA

2 Dens tempA @ 20mA 14 Dens B temp HI limit B:1

3 Dens tempA @ 0/4mA 15 Dens B temp LO limit B:1

4 Dens A temp HI lmt B:1 16 Dens B temp step lmt B:2

5 Dens A temp LO lmt B:1 17 Dens tempB FB type C

6 Dens A temp step lmt B:2 18 Dens tempB FB val C

7 Dens tempA FB type C 19 Dens temp B offset D

8 Dens tempA FB val C 20 Density B temp *

9 Dens temp A offset D 21 Prime txdr dens sel MENU(3)

10 Density A temp * A 22 Header dens temp *

11 Dens tempB source 23 Header dens temp FB

12 Dens tempB @ 20mA - Flow system type E

Notes: Separate location value (and state) for each of four metering-points but accessible through same menu page

A Ensure that the basic configuration information of the live input channel has been completed Analogue Input…..….…… Turn to reference page 11.6 HART Input……….………. Turn to Chapter 17

B:1 Optional HI and LO alarm limits. Programming these limits with a zero value will avoid maximum and

minimum limit checks on the LIVE value of the associated parameter B:2 Optional STEP alarm limit. Program it with a 0 value to avoid a continuous check on the difference between

two LIVE values of the associated parameter. Comparison values are from the present and previous cycles C Optional fallback facility for the associated measurement D Optional parameter for on-line correction to the LIVE associated measurement E This parameter setting has a significant impact on many other measurements. [MENU(4)]


Page 11.36 7955 2540 (CH011/AF)

11.14 HEADER ‘VISCOSITY’ TEMPERATURE (1X4X1 SCHEME)

Measurements Supported: • ‘Viscosity loop’ fluid temperature ‘A’ – at the Header • ‘Viscosity loop’ fluid temperature ‘B’ – at the Header • Prime selected Header ‘viscosity loop’ fluid temperature

Figure 11.14-1: Header 'Viscosity Loop' Temperature Blocks and Parameters (1x4x1 Scheme)


10

1mA inputs

HART inputs

PT100 inputs


PT100 or HART

2 3


20

11mA inputs

HART inputs

PT100 inputs


PT100 or HART

12 13

HeaderSelection

22

21

VISCOSITYTEMPERATURE 'A'

VISCOSITYTEMPERATURE 'B'

HEADER(VISCOSITY)

TEMPERATURE

23


4 5 6

7 8

ApplyOffset

9

ApplyOffset

19


14 15 16

17 18

Menu Navigation List: (1) <“Configure”>/<“Temperature”>/<“Viscometer temp”, (2) <“Temperature”>/<“Visc temperature”> and (3) <“Configure”>/<“Viscosity”>/<“Header visc”> and (4) <”Configure”>/<”Transducer details”>/<”Flow system type”> Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 1 Visc A temp source A 13 Visc B temp @ 0/4mA

2 Visc A temp @ 20mA 14 Visc B temp HI limit B:1

3 Visc A temp @ 0/4mA 15 Visc B temp LO limit B:1

4 Visc A temp HI limit B:1 16 Visc B temp step lmt B:2

5 Visc A temp LO limit B:1 17 Visc B temp FB type C

6 Visc A temp step lmt B:2 18 Visc B temp FB value C

7 Visc A temp FB type C 19 Visc B temp offset D

8 Visc A temp FB value C 20 Visc B temperature *

9 Visc A temp offset D 21 Header visc select MENU(3)

10 Visc A temperature * 22 Header visc temp *

11 Visc B temp source A 23 Prime visc temp FB

12 Visc B temp @ 20mA - Flow system type E


A Ensure that the basic configuration information of the live input channel has been completed



minimum limit checks on the LIVE value of the associated parameter

B:2 Optional STEP alarm limit. Program it with a 0 value to avoid a continuous check on the difference between two LIVE values of the associated parameter. Comparison values are from the present and previous cycles

C Optional fallback facility for the associated measurement

D Optional parameter for on-line correction to the LIVE associated measurement

E This parameter setting has a significant impact on many other measurements. [MENU(4)]


7955 2540 (CH011/AF) Page 11.37

11.15 METERING FLUID TEMPERATURE

Measurement Supported: (Also, see page 11.46 for use of fluid temperature measurements)

• Fluid temperature - at up to four metering-points

Figure 11.15-1: Metering-point Fluid Temperature Blocks and Parameters


1mA inputs

HART inputs

PT100 inputs


PT100 or HART

2 3

ApplyOffset

4

METER-RUNTEMPERATURE


5 6

7 8

9

Menu Navigation List: (1) <“Configure”>/<“Temperature”>/<“Meter run temp”> and (2) <“Temperature”>/<“Meter run temp”> Menu Data List: * shows data that can be “Live” or “Set”


1 Meter temp input src A, 6 MeterRun temp LO lmt B,

2 Meter temp @ 20mA 7 Meter temp FB type C,

3 Meter temp @ 0/4mA 8 Meter temp FB value C,

4 MeterRun temp offset D, 9 MeterRun temperature*

5 MeterRun temp HI lmt B,




B Optional HI and LO alarm limits. Programming these limits with a zero value will avoid maximum and

minimum limit checks on the LIVE value of the associated parameter C Optional fallback facility for the associated measurement D Optional parameter for on-line correction to the LIVE associated measurement


Page 11.38 7955 2540 (CH011/AF)

11.16 HEADER ‘DENSITY’ PRESSURE (1X4X1 SCHEME)

Measurement Supported: (Also, see page 11.46 for use of Header pressure measurements)

• ‘Density loop’ pressure - at the Header

Figure 11.16-1: Header 'Density Loop' Pressure Blocks and Parameters


9

1

mA inputsHART inputs

PressureCalculation(Scaling)


HART

2 3 4 5

7 8

HEADER PRESSURE

6

Menu Navigation List: (1) <“Configure”>/<“Pressure”>/<“Header pressure”>, (2) <“Pressure”>/<“Header dens press”> and (3) <”Configure”>/<”Transducer details”>/<”Flow system type”> Menu Data List: * shows data that can be “Live” or “Set”


1 Head press source A 6 Dens press step lmt B:2

2 Head press @ 20mA 7 Head press FB type C

3 Head press @ 0/4mA 8 Head press FB val (C)

4 Dens press HI lmt B:1 9 Header dens press *

5 Dens press LO lmt B:1 - Flow system type D

Notes:

Separate location value (and state) for each of four metering-points but accessible through same menu page A Ensure that the basic configuration information of the live input channel has been completed



minimum limit checks on the LIVE value of the associated parameter B:2 Optional STEP alarm limit. Program it with a 0 value to avoid a continuous check on the difference between

two LIVE values of the associated parameter. Comparison values are from the present and previous cycles C Optional fallback facility for the associated measurement D This parameter setting has a significant impact on many other measurements. [MENU(3)]


7955 2540 (CH011/AF) Page 11.39

11.17 METERING PRESSURE

Measurement Supported: • Pressure at up to four metering-points

Figure 11.17-1: Metering Pressure Blocks and Parameters


8

1

mA inputs

HART inputs

PressureCalculation(Scaling)


HART

2 3 4 5

6 7

METER-RUNPRESSURE

Menu Navigation List: (1) <“Configure”>/<“Pressure”>/<“Meter run pressure”> and (2) <“Pressure”>/<“Meter run press”> Menu Data List: * shows data that can be “Live” or “Set”


1 Meter press source A, 6 Meter press FB type C,

2 Meter press @ 20mA 7 Meter press FB value C,

3 Meter press @ 0/4mA 8 Meter run pressure *

4 Meter press HI lmt B,

5 Meter press LO lmt B,




B Optional HI and LO alarm limits. Programming these limits with a zero value will avoid maximum and

minimum limit checks on the LIVE value of the associated parameter C Optional fallback facility for the associated measurement


Page 11.40 7955 2540 (CH011/AF)

11.18 HEADER DENSITY (1X4X1 SCHEME) Measurements Supported: (Also, see page 11.46 for main use of prime selected Header density)

• Fluid Density ‘A’ at the Header – from either a liquid density transducer or a 7827 viscosity analyser 5 • Fluid Density ‘B’ at the Header – as fluid density ‘A’ but with the additional option of a mA or HART Input • Prime selected Header density – from fluid density ‘A’ or ‘B’ or fallback facility

Figure 11.18-1: Header Density Blocks and Parameters

Index for use with list of associated data

DENSITY A#BCOMPARISON

LIQUIDDENSITY 'A'Density 'A'

CalculationApply Other

FactorsTemperatureCorrection

PressureCorrection

VOSCorrection

tA (Header)

3 4

5 6 7 8 9 10 11 12 13 14 15 16

18

PHeader

LIQUIDDENSITY 'B'

Density 'B'Calculation

Apply OtherFactors

TemperatureCorrection

PressureCorrection

VOSCorrection

24

25 26 27 28 29 30 31 32 33 34 35 36 37

41

mA inputHART input

Density 'B'Calculation

SourceSelection

mA

HART

38

19

39 40

XX

1a2

Density 'B'Selection

20

(ρ A)(μ S)

17

42HEADER mA

DENSITY

1bOR

(μ S)

23

21a22

(μ S)

21bOR

(μ S)

tB (Header)

PHeader

(ρ B)

HeaderDensity

Selection

43

Limits &FallbackChecks

44 45

46 47

Update fromProduct

Detection

ρ Head

48

Menu Navigation List: (1) <“Configure”>/<“Transducer details”>/<Densitometer…>, (2) <“Health check”>/<”Inputs”>/<“Time period inputs”>, (3) <“Configure”>/<“Density”>/<“Header dens”> and (4) <”Configure”>/<”Transducer details”>/<”Flow system type”> Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 1a Time period input 1 * (A) 21a Time period input 2 *

1b Time period input 1b * (A) 21b Time period input 2b *

2 Time period 1 type A 22 Time period 2 type 3 Dens1 glitch limit 23 Dens2 glitch limit 4 Density1 K0 24 Density2 K0 5 Density1 K1 25 Density2 K1 6 Density1 K2 26 Density2 K2 7 Density1 correct E 27 Density2 correct 8 Density1 K18 28 Density2 K18 9 Density1 K19 29 Density2 K19

10 Density1 K20a 30 Density2 K20a 11 Density1 K20b 31 Density2 K20b 12 Density1 K21a 32 Density2 K21a 13 Density1 K21b 33 Density2 K21b 14 Density1 Txdr type E 34 Density2 Txdr type 15 Density1 VOS 35 Density2 VOS 16 Density1 offset 36 Density2 offset 17 Dens Meter Factor 1 37 Dens Meter Factor 2 18 Density A * 38 DensityB Ain src 19 Header dens comp lmt D 39 DensityB @ 20mA 20 DensityB calc sel 40 DensityB @ 0/4mA

5 The 7827 viscosity analyser does not measure fluid density as accurately as a 783x/784x liquid density transducer. Density measurements from a 7827 also require a correction for viscosity effects if the fluid viscosity exceeds 100cP.


7955 2540 (CH011/AF) Page 11.41

HEADER DENSITY (1X4X1 SCHEME) CONFIGURATION

(Menu Data List continued…) * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 41 Density B * 47 Prime dens FB val H

42 Head analog dens * B 48 Header dens *

43 Select header dens F tA Density A temp *

44 Dens HI limit G tB Density B temp *

45 Dens LO limit G PHead Header dens press *

46 Prime dens FB type H - Flow system type C

Notes:

A The “Density” option (value) is for when the fluid density ‘A’ measurement involves a liquid density transducer. Live transducer values will appear in the <“Time period Input 1”> menu data page (location).

The “7827” option (value) is for when the fluid density ‘A’ measurement involves a 7827 viscosity analyser. Live 7827 values will appear in the <“Time Period Input 1b”> menu data page (location) instead of the <“Time Period Input 1”> menu data page (location).

(Chapter 2 features time period input and analogue input rear panel connections)

B This measurement can be used by the Product Detection feature. (See “Interface Detection” pages)

C This parameter setting has a significant impact on many other measurements. [MENU(4)]

D This alarm limit checking can be switched off by setting a large enough density value that will always greater than the difference between density ‘A’ and density ‘B’ measurements.

E Various combinations of corrections to density can be selected, as shown in Table 11.18.1. Table 11.18.2 then shows the applicability of selected corrections when using different types of transducer.

F Select a logic table to be used by the Flow Computer to perform header density channel re-selection. (For details, turn to the “Header Density Re-selection Procedure” section on page 11.42)

G High and low alarm limits are applied to the selected (prime) header density value. These limits are not checked when both limits are ‘SET’ to zero.

H Value can be overwritten by the Product Detection feature. (See “Interface Detection” reference pages)

Table 11.18.1: Menu data option descriptors for selecting corrections

Option Descriptor (as displayed)

Correction: Temperature

Correction: Pressure

Correction: VOS

Correction: Viscosity

None

Temp

Press

VOS

Temp press

Temp VOS

Press VOS

Temp press VOS

Table 11.18.2: Applicability of Corrections to Density (by transducer)

Transducer Type

Temperature Effects

Pressure Effects

Viscosity Effects*

VOS Effects

7827

783x/784x 1762

* Density measurements from a 7827 do require a correction for viscosity effects when the fluid viscosity exceeds 100cP.


Page 11.42 7955 2540 (CH011/AF)

HEADER DENSITY (1X4X1 SCHEME) CONFIGURATION

Header Density Re-Selection Procedure In the event of a density input channel (e.g. density ‘A’) failing or returning to a live state, the 7955 will perform a re-selection procedure for obtaining Header Density value from an alternative source. This procedure involves evaluating a user-selected logic decision table to determine where now to get the prime value.

Table 11.18.3: Logic table for the “Automatic A” configuration option

Key:

A = Density ‘A’, B = Density ‘B’, FB = Fallback Notes:

1. The “Automatic B” configuration option uses the same logic table except Density ‘B’ is the preferred channel.

This preference reverses the A and B selection in the last column of this table. 2. “Out of limit” columns 1 and 2 are concerned with the HI or LO alarm limits. 3. “Input failed” columns are concerned with ‘Live’ inputs.

Table 11.18.4: Logic table for the “Density A” configuration option

Key: A = Density ‘A’, B = Density ‘B’, FB = Fallback

Table 11.18.5: Logic table for the “Density B” configuration option

Key: A = Density ‘A’, B = Density ‘B’, FB = Fallback

Density ‘A’ Out of Limit

Density ‘B’ Out of Limit

A#B (Comp) Out of Limit

Density ‘A’ Input Failed

Density ‘B’ Input Failed

Density Selected

Yes Yes Yes No No FB No Yes Yes No No A Yes No Yes No No B No No Yes No No B Yes Yes No No No A No Yes No No No A Yes No No No No B No No No No No A Yes Yes Yes Yes No FB No Yes Yes Yes No FB Yes No Yes Yes No B No No Yes Yes No B Yes Yes No Yes No B No Yes No Yes No FB Yes No No Yes No B No No No Yes No B Yes Yes Yes No Yes FB No Yes Yes No Yes A Yes No Yes No Yes FB No No Yes No Yes A Yes Yes No No Yes FB No Yes No No Yes A Yes No No No Yes FB No No No No Yes A Yes Yes Yes Yes Yes FB No Yes Yes Yes Yes FB Yes No Yes Yes Yes FB No No Yes Yes Yes FB Yes Yes No Yes Yes FB No Yes No Yes Yes FB Yes No No Yes Yes FB No No No Yes Yes FB

Density ‘A’ Out of Limit

Density ‘A’ Input Failed

Density Selected

No No A

No Yes FB

Yes No FB

Yes Yes FB

Density ‘B’ Out of Limit

Density ‘B’ Input Failed

Density Selected

No No B

No Yes FB

Yes No FB

Yes Yes FB


7955 2540 (CH011/AF) Page 11.43

EQUATION LIST HEADER DENSITY (1X4X1 SCHEME) Density Equation List:

(Menu data listed is for channel ‘A’. Menu data for channel ‘B’ is shown in the menu data listed on page 11.40)

IMPORTANT NOTICE

Density measurements from a 7827 viscometer are supported. However, the density corrections for viscosity effects and VOS effects are not available in software version 2540.

The viscosity effect correction is normally required for fluids with a viscosity > 100cP.

For further information on these corrections, refer to the 7827 Viscometer Technical Manual.

Equation DE#1a: Uncorrected density from a liquid density transducer

Using: uρ =( ) ( )2

210 *K*KK ττ ++

Where: uρ = Density (uncorrected)……………………………..…………. Menu Data: <”Density A”>

0K = Transducer calibration factor K0………………….………… Menu Data: <”Density1 K0”> K1 = Transducer calibration factor K1………………….………… Menu Data: <”Density1 K1”>

2K = Transducer calibration factor K2………………….………… Menu Data: <”Density1 K2”>

τ = Periodic time from transducer (μs)………………..………... Menu Data: <”Time Period Input 1”> Equation DE#1b: Uncorrected density from a 7827 liquid viscosity transducer

Using: uρ =( ) ( )2

B2B10 *K*KK ττ ++

Where: uρ = Density (uncorrected)………………………………...………. Menu Data: <”Density A”>

0K = Transducer calibration factor K0……………………..……... Menu Data: <”Density1 K0”>

1K = Transducer calibration factor K1………………….…..…….. Menu Data: <”Density1 K1”>

2K = Transducer calibration factor K2….……………………........ Menu Data: <”Density1 K2”>

Bτ = Periodic time from transducer (μs)………………..………… Menu Data: <”Time Period Input 1b”>

Equation DE#2: Density corrected for temperature effects

This equation corrects a density measurement for the temperature effect on the metalwork of the transducer when operated away from the calibration temperature.

Using: tρ = ( ) ( )[ ]bbu ttKttK −+−+ **1* 1918ρ

Where: ρt = New density (temperature corrected)…………….……….… Menu Data: <”Density A”>

ρu = Density without temperature correction………………..…... Menu Data: <”Density A”>

18K = Transducer calibration factor K18……………………..…..... Menu Data: <”Density1 K18”>

19K = Transducer calibration factor K19…….…………….………. Menu Data: <”Density1 K19”>

t = ‘Density loop’ temperature…………..………………………. Menu Data: <”Density A temp”>

bt = Transducer calibration temperature (always 20°C).….…… (Not displayed in menu)


Page 11.44 7955 2540 (CH011/AF)

HEADER DENSITY (1X4X1 SCHEME) EQUATION LIST


Equation DE#3: Density corrected for pressure effects

This equation corrects a density measurement for the pressure effect on the metalwork of the transducer when operated away from the calibration pressure.

Using: Pρ = ( )( ) ( )bb PPKPPK −+−+ **1* 2120ρ

Where: Pρ = New density (pressure corrected)…….…………………… Menu Data: <”Density A”> ρ = Density without pressure correction……………….…...… Menu Data: <”Density A”> P = ‘Density loop’ pressure…………….………………………. Menu Data: <”Header dens press”>

bP = Transducer calibration pressure (always 1 bar Abs.)…… (Not displayed in menu)

And: 20K = ( )BBA PPKK −+ *2020 ………………………………… (Not displayed in menu)

21K = ( )BBA PPKK −+ *2121 ……………………….………… (Not displayed in menu)

Where: AK20 = Transducer calibration factor K20A……………...……….. Menu Data: <”Density1 K20a”>

BK20 = Transducer calibration factor K20B……………...……….. Menu Data: <”Density1 K20b”>

AK21 = Transducer calibration factor K21A……………...……….. Menu Data: <”Density1 K21a”>

BK21 = Transducer calibration factor K21B………………...…….. Menu Data: <”Density1 K21b”>

Equation DE#4: Density corrected for VOS effects [NOT AVAILABLE TO 7827 USERS]

This equation corrects a density measurement for the VOS effect of the measured liquid compared to the VOS effect on the calibration liquid at the same conditions.

Using: vρ = ⎟⎟

⎠

⎞

⎜⎜

⎝

⎛⎟⎟⎠

⎞⎜⎜⎝

⎛+

⎟⎟⎟

⎠

⎞

⎜⎜⎜

⎝

⎛⎟⎟⎠

⎞⎜⎜⎝

⎛+

2

2

*1

*1

*

A

vos

C

vos

VOSK

VOSK

τ

τρ

Where: vρ = New density with VOS correction………..……………… Menu Data: <”Density A”> ρ = Density without VOS correction………..……………….. Menu Data: <”Density A”> τ = Periodic time from transducer (μs)……………………... Menu Data: <”Time Period Input 1”>

AVOS = VOS (velocity of sound) of measured liquid…………… Menu Data: <”Density1 VOS”>

CVOS = VOS (velocity of sound) of calibration liquid.………….. See Equation DE#5

vosK = Value automatically selected from a built-in table…….. (Not displayed in menu)

Table 11.18.6: KVOS values for Equation DE#4

Transducer KVOS

1762 28500

7830/7840 35900

7835/7845 19800

7826 67800


7955 2540 (CH011/AF) Page 11.45

EQUATION LIST HEADER DENSITY (1X4X1 SCHEME)


Equation DE#5: VOS (velocity of sound) effects of calibration fluid

This equation is for generating a factor for the VOS effect on the calibration liquid under present flow conditions. It is used in association with Equation DE#4.

Using: VOSC = ( ) ( ) ( )34

2321 *** ρρρ vosvosvosvos KKKK +++

Where: VOSC = New VOS (velocity of sound) of calibration fluid…….... (Not displayed in menu) ρ = Density without VOS correction…………………………. Menu Data: <”Density A”>

1vosK = Value from column 2 of Table 11.18.7…………………… (Not displayed in menu)




Table 11.18.7: KVOS values for Equation DE#5

Transducer KVOS1 KVOS2 KVOS3 KVOS4

1762 1157 0 0 0.000000343

7830/7840 214.91 0.15941 0.0025398 -0.0000014169

7835/7845 214.91 0.15941 0.0025398 -0.0000014169

7826 230.915 0.126713 0.00255082 -0.0000014164


Page 11.46 7955 2540 (CH011/AF)

11.19 API REFERRED DENSITY (1X4X1 SCHEME)

Measurements Supported: (For alternative referral calculations, turn to pages 11.47 and 11.48)

• Base density – at four metering-points – by API calculation (Header to Base referral) • Metering density – at four metering-points – direct from Header or by API calculation (Base to Metering referral)

API 2540 Standard Compliance (1) General Crude Oil API Std 2540, Chapter 11.1 Tables 23A & 24A, 53A & 54A (SG range is 0.6610 to 1.076) (2) General Products API Std 2540, Chapter 11.1 Tables 23B & 24B, 53B & 54B (SG range is 0.6535 to 1.076) (3) User-defined K0, K1 API Std 2540, Chapter 11.1 Tables 24C, 54C

Figure 11.19-1: API Referred Density Blocks and Parameters

PHead

ρHead

tHead

METERDENSITY

API Referral(Base=>Meter)

ReferredDensity

83

94

API Referral(Base density)

1

6 75

10

8 95

6 7

MethodSelection

Header Density

20

t Meter

11 12 13 14

19ReferralMethod

Selection

ρBase

HI

21 22

Index for use withlist of associated data

XX

LO

Ctld Cpldα15 Fd

15 16 17 18Ctl Cpl

α15 F

2ρMeter

24

25

23

26P Meter

Menu Navigation List: (1) <“Configure”>/<“Density”>, (2) <“Configure”>/<“Base density”>, (3) <“Density”>, (4) <“Base density”> (5) <“Temperature”>, (6) <“Pressure”> and (7) <”Configure”>/<”Transducer details”>


Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 1 Header dens * E 15 CTL 2 Base dens method , D 16 CPL 3 Base temperature MENU(5) 17 API compress factor 4 Base press value MENU(6) 18 API alpha coeff 5 Equilibrium press MENU(6) 19 Meter dens/visc sel C 6 API product select 20 Meter run density * 7 API range select 21 Base dens HI limit 8 API User K0 22 Base dens LO limit 9 API User K1 23 MeterRun temperature * A,

10 Base density * 24 Header dens temp * A

11 CTLd 25 Header dens press * B

12 CPLd 26 Meter run pressure * B

13 API alpha d coeff – Flow system type F

14 API compress fact d


A See configuration reference pages 11.35 and 11.37.

B See configuration reference pages 11.38 and 11.39.

C Select the “Calculation” option (value) unless there is a need to by-pass the density referral calculations for all four metering-points. [MENU(6)]

D Select a referral calculation for each metering-point. For API Std 2540, choose the “API” option. [MENU(2)]

E API referral calculation requires the prime Header density value to be in the range of 350 - 1074 Kg/m3. (Header density information starts on page 11.40)

F This parameter setting has a significant impact on many other measurements. [MENU(7)]


7955 2540 (CH011/AF) Page 11.47

11.20 4X5 MATRIX REFERRED DENSITY (1X4X1 SCHEME)

Measurements Supported: (For alternative referral calculations, turn to pages 11.46 and 11.48)

• Base density – at four metering-points – by 4x5 matrix referral calculation (Header to Base referral) • Metering density – at four metering-points – direct from Header or by API calculation (Base to Metering referral)

Figure 11.20-1: 4x5 Matrix Referred Density Blocks and Parameters

METERDENSITY

Matrix Referral(Base to Meter)

ReferredDensity

3

Matrix Referral(Base density)

1

28 2927

30 MethodSelection

Header Density

34

33ReferralMethod

Selection

2 3 28 2927


XX

ρHeadρBase

HI

21 22LO3635 35 36

ρMeter

PHead

tHead

t Meter

38

39

37

P Meter 40




1 Header dens * 22 Density matrix R32 2 Base dens method D, 23 Density matrix R33 3 Density matrix T0 24 Density matrix R40 4 Density matrix T1 25 Density matrix R41 5 Density matrix T2 26 Density matrix R42 6 Density matrix T3 27 Density matrix R43 7 Density matrix T4 28 Density K40 8 Density matrix R00 29 Density K41 9 Density matrix R01 30 Base density *

10 Density matrix R02 31 Base dens HI limit 11 Density matrix R03 32 Base dens LO limit 12 Density matrix R10 33 Meter dens/visc sel C

13 Density matrix R11 34 Meter run density * 14 Density matrix R12 35 Base temperature MENU(5) 15 Density matrix R13 36 Base press value MENU(6)

16 Density matrix R20 37 MeterRun temperature * A, 17 Density matrix R21 38 Header dens temp* A

18 Density matrix R22 39 Header dens press* B

19 Density matrix R23 40 Meter run pressure * B

20 Density matrix R30 – Flow system type E

21 Density matrix R31


A See configuration reference pages 11.35 and 11.37.

B See configuration reference pages 11.38 and 11.39.


D Select a referral calculation for each metering-point. [MENU(2)]



Page 11.48 7955 2540 (CH011/AF)

11.21 KNOWN FLUID DENSITY REFERRAL (1X4X1 SCHEME)

Measurements Supported: (For the meter density measurement, see the next page)

• Base Density of a known fluid - at up to four metering-points - by referral calculation

Figure 11.21-1: Known Fluid Base Density Blocks and Parameters


XX

1

ρHead RelativeDensityCalc.

γHead GPA TP25Table 23E

γ60F GPA TP25Table 24E

CTL 60F(Head)

tHead

GPA TP25Table 24E CTL 60F

(Base)

CalculateCTL

CalculateBase Density

NGL/LPG(GPA TP25)3tBase

CTL(Base)

11 ρBase

3 4

API Std 2540Referral

(Head Base)

HI

9

10LO

1ρHead

CPL(Base)

PHead

CalculateBase Densityof Ethylene(API 2565)

CalculateBase Densityof Ethylene

(IUPAC)

CalculateBase Densityof Propylene(API 2565)

StandardSelection

3 4

3 4

3 4tBase

tBase

tBase PBase

PBase

PBase

tHead 6

ρBase(4x5 Matrix or API)

tBase PBase

1

6

5

ρHead

8

Director

Referral

2ρRun

7PE




1 Header dens * (E) 7 Equilibrium press MENU(6)

2 Meter dens/visc sel C 8 Base dens method D

3 Base temperature MENU(5) 9 Base dens HI limit

4 Base press value MENU(6) 10 Base dens LO limit

5 Header dens temp * A 11 Base density * 6 Header dens press * B – Flow system type F


A Observed temperature. See configuration reference page 11.35

B Observed pressure. See configuration reference page 11.38



E API (Std 2540) referral is performed for a generalised product where the Header density is within the range of 350 to 1074 Kg/m3. (Header density information starts on page 11.40)


Standards Compliance NGL/LPG GPA Technical Publication TP25, Tables 24E & 23E (SG range is 0.495 to 0.637) Ethylene IUPAC Ethylene API 2565 Chapter 11.3.2.1 Propylene API 2565 Chapter 11.3.3.2


7955 2540 (CH011/AF) Page 11.49

KNOWN FLUID DENSITY REFERRAL (1X4X1 SCHEME)

Measurements supported: (For the base density measurement, see previous page)

• Meter Density of a known fluid - for up to four metering-points - direct from Header or by referral calculation

Figure 11.21-2: Meter Density - Known Fluid - Blocks and Parameters (1x4x1)


XX

1

ρBase RelativeDensityCalc.

γBase GPA TP25Table 23E

γ60F

GPA TP25Table 24E

CTL 60F(Meter)

tBase

GPA TP25Table 24E

CTL 60F(Base)

CalculateCTL

CalculateMeter Density

NGL/LPG(GPA TP25)

tMeter

CTL

(Meter)

9 ρMeter

2 3

API Std 2540Referral

(Base Meter)

1ρBase

CPL(Meter)

PBase

CalculateMeter Density

of Ethylene(API 2565)

CalculateBase Densityof Ethylene

(IUPAC)

CalculateMeter Densityof Propylene(API 2565)

StandardSelection

5

6

tMete

r

PMeter

tBase 2

ρMeter(4x5 Matrix or API)

tMeter

PMeter

1

6

2

ρBase

7

4PE

3

4

tMete

r

PMeter

tBase

2

5

4

tMeter

PMeter

5

tBase

Direct/IndirectDensity

ρHead 8

ρ

Menu Navigation List: (1) <“Configure”>/<“Density”>, (2) <“Configure”>/<“Base density”>, (3) <“Density”>, (4) <“Base density”> (5) <“Temperature”>, (6) <“Pressure”> and (7) <”Configure”>/<”Transducer details”> Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 1 Base density * (E) 6 Meter run pressure * B, 2 Base temperature MENU(5) 7 Base dens method D 3 Base press value MENU(6) 8 Meter dens/visc sel C

4 Equilibrium press MENU(6) 9 Meter run density * 5 MeterRun temperature * A, – Flow system type F


A Observed temperature. See configuration reference page 11.37

B Observed pressure. See configuration reference page 11.39

C Select the “Calculation” option (value) when using density referral calculation


E API (Std 2540) referral is performed for a generalised product where the Header density is within the range of 350 to 1074 Kg/m3. (Base density information starts on page 11.48)


Standards Compliance NGL/LPG GPA Technical Publication TP25, Tables 24E & 23E (SG range is 0.495 to 0.637) Ethylene IUPAC Ethylene API 2565 Chapter 11.3.2.1 Propylene API 2565 Chapter 11.3.3.2


Page 11.50 7955 2540 (CH011/AF)

11.22 METERING DENSITY (4X4X4 SCHEME)

Measurement Supported: (Base density measurement support for Ethylene or Propylene is on page 11.52)

• Metering Density – at up to four metering-points – from liquid density transducers or 7827 viscosity analysers 6 • Base Density of fluid (other than Ethylene and Propylene) – not supported by 4x4x4 scheme. See note above.

Figure 11.22-1: Meter Density Blocks and Parameters (4x4x4)

Index for use with list of associated dataXX

METERDENSITY

DensityCalculation

Apply OtherFactors


PressureCorrection

VOSCorrection

45 6 7 8 9 10 11 12 13 14 15 16 17

24

3

ρMeter

Fallback &Limits Check

18 19 20 21

PMetertMeter

1a2

(μS)

1bOR

(μS)

22 23

25ρTxdr

Menu Navigation List: (1) <“Configure”>/<“Transducer details”>/<Densitometer…> or <“Configure”>/<“Transducer details”>/<Viscometer…> (2) <“Health check”>/<”Inputs”>/<“Time period inputs”>, (3) <“Configure”>/<“Density”>, (4) <“Density”> (5) <“Temperature”> and (6) <“Pressure”> Menu Data List 1 of 2: * shows data that can be “Live” or “Set”




Menu Data (as displayed) Index

(Metering-point 1) (Metering -point 2) (Metering-point 3) (Metering-point 4)

Notes?

1a Time period input 1 * Time period input 2 * Time period input 3 * Time period input 4 * (A)

1b Time period input 1b * Time period input 2b * Time period input 3b * Time period input 4b * (A)

2 Time period 1 type Time period 2 type Time period 3 type Time period 4 type A

3 Dens1 glitch limit Dens2 glitch limit Dens3 glitch limit Dens4 glitch limit

4 Density1 K0 Density2 K0 Density3 K0 Density4 K0



7 Density1 correct Density2 correct Density3 correct Density4 correct



10 Density1 K20a Density2 K20a Density3 K20a Density4 K20a

11 Density1 K20b Density2 K20b Density3 K20b Density4 K20b

12 Density1 K21a Density2 K21a Density3 K21a Density4 K21a

13 Density1 K21b Density2 K21b Density3 K21b Density4 K21b

14 Density1 Txdr type Density2 Txdr type Density3 Txdr type Density4 Txdr type

15 Density1 VOS Density2 VOS Density3 VOS Density4 VOS

16 Density1 offset Density2 offset Density3 offset Density4 offset

17 Dens Meter Factor 1 Dens Meter Factor 2 Dens Meter Factor 3 Dens Meter Factor 4 Menu Data List 2 of 2: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 18 Dens Txdr FB type D, 23 Meter run pressure * 19 Dens Txdr FB val (D) 24 Density txdr value * 20 Dens Txdr HI limit C, 25 Meter run density * 21 Dens Txdr LO limit C, – Flow system type E

22 MeterRun temperature * – Meter dens/visc sel D

Notes are on the next page



7955 2540 (CH011/AF) Page 11.51

CONFIGURATION METER DENSITY (4X4X4 SCHEME)


A The “Density” option (value) is for when the fluid density ‘A’ measurement involves a liquid density

transducer. Live transducer values will appear in the <“Time period Input 1”> menu data page (location).


(Chapter 2 features time period input and analogue input rear panel connections) B Select the “Transducer” option for this measurement set-up C Optional HI and LO alarm limits. Programming these limits with a zero value will avoid maximum and

minimum limit checks on the LIVE value of the associated parameter D Optional fallback facility for the associated measurement E This parameter setting has a significant impact on many other measurements. [MENU(7)]


Page 11.52 7955 2540 (CH011/AF)

11.23 BASE DENSITY OF KNOWN FLUID (4X4X4 SCHEME)

Measurements Supported: • Base density of known fluid - at up to four metering-points - by referral

• Metering density of a known fluid – as described on page 11.50

Figure 11.23-1: Base Density Blocks and Parameters (4x4x4)

6 ρBase

HI

4

5LO

Calculate Base Densityof Ethylene(API 2565)

Calculate Base Densityof Ethylene

(IUPAC)

Calculate Base Densityof Propylene(API 2565)

StandardSelection

1 2

1 2

1 2

tBase

tBase

tBase PBase

PBase

PBase

3

Menu Navigation List: (1) <“Configure”>/<“Base density”>, (2) <“Temperature”>, (3) <“Pressure”> and (4) <”Configure”>/<”Transducer details”> Menu Data List: * shows data that can be “Live” or “Set”


1 Base temperature MENU(2) 4 Base dens HI limit

2 Base press value MENU(3) 5 Base dens LO limit 3 Base dens method B, 6 Base density *

– Flow system type C – Meter dens/visc sel B


A You must select the “Calculation” option (value) for base density measurements on this page. [MENU(4)] B Select a referral calculation for each metering-point. [MENU(1)] C This parameter setting has a significant impact on many other measurements. [MENU(4)]

Known Fuid Standards ComplianceEthylene IUPAC Ethylene API 2565 Chapter 11.3.2.1 Propylene API 2565 Chapter 11.3.3.2


7955 2540 (CH011/AF) Page 11.53

11.24 SPECIFIC GRAVITY/DEGREES API

Measurement Supported: • Specific gravity of metered fluid – for up to four metering-points

Equation DE#6: Specific gravity of fluid

Using: SG = ρρ

Base

Water

SG = Specific gravity of measured fluid

ρBase = Base density of measured fluid

ρWater = Water density

Menu Navigation List: (1) <“Configure”>/<“Specific gravity”> and (2) <“Base density”> Menu Data List: * shows data that can be “Live” or “Set”


1 Base density * , A 4 SG HI limit , C

2 Water density (SG) * B 5 SG LO limit , C

3 Specific gravity *


A 1x4x1: Turn to pages 11.46, 11.47 and 11.48 for details on configuring for base density measurements

4x4x4: Turn to pages 11.50 and 11.52 for details on configuring for base density measurements B This parameter is independent of the support for net oil/water calculations C Optional alarm limits for specific gravity values Measurement Supported: • Degrees API – for up to four metering-points

Equation DE#7: Degrees API for measured fluid

Using: oAPI = 5.1315.141

−SG

Where: oAPI = Degrees API

SG = Specific gravity Menu Navigation List: (1) <“Density”>/<”Degrees API”> and (2) <“Configure”>/<“Specific gravity”> Menu Data List: * shows data that can be “Live” or “Set”


1 Degrees API * 2 Specific gravity *

Note: Separate location value (and state) for each of four metering-points but accessible through same menu page

2

1 Specific GravityCalculation

3

4

5

ρBSpecific Gravity

1 Degrees APICalculation

2Specific Gravity

DegreesAPI


Page 11.54 7955 2540 (CH011/AF)

11.25 SPECIAL EQUATIONS

Feature: • Special Equation Type One - available to each metering-point

Although this special equation can be used for any purpose, the typical application is for calculating, for example, Degrees Brix for non-linear products.

Equation SPE#1: Special Equation Type One

Using: ( )( )⎟⎟⎠

⎞⎜⎜⎝

⎛

+

++=

fYedcXbaBAR

**

)**

Where: A , B = Constants

a - f = Pointers

X , Y = Constants

R = Result

Menu Navigation List: (1) <“Configure”>/<“Special equations”>


Term Menu Data (as displayed) Notes? Term Menu Data (as displayed) Notes?

R Special equation 1 * N/A General constant 1 , C A General equ 1 const A N/A General constant 2 , C B General equ 1 const B N/A General constant 3 , C X General equ 1 const X N/A General constant 4 , C

Y General equ 1 const Y a General equ 1 ptr a , B

b General equ 1 ptr b , B

c General equ 1 ptr c , B

d General equ 1 ptr c , B

e General equ 1 ptr d , B

f General equ 1 ptr e , B N/A Special eq 1 name , A


A A facility is provided whereby a text title can be edited to give the calculation a meaningful name. Changing

the default text will alter the on-screen description of the result menu data page. B Edit the value with the database location identification (ID) number of the parameter to be used for this term.

ID numbers can be seen on-screen by locating the parameter within the menu system and then pressing the ‘a’ softkey. With this type of configuration parameter, the word “off” is seen when it is not in use.

C There is a collection of unused database locations visible within the custom equation menu. These are

provided for defining constants that could be identified as equation terms ‘a’, ‘b’, etc.


7955 2540 (CH011/AF) Page 11.55

11.26 HEADER ‘VISCOSITY’ DENSITY (1X4X1 SCHEME)Measurements Supported: (Turn to page 11.57 for main use of prime selected Header ‘viscosity’ density)

• ‘Viscosity loop’ Fluid Density ‘C’ at the Header – from either a density transducer or a 7827 viscosity analyser 7 • ‘Viscosity loop’ Fluid Density ‘D’ at the Header – as fluid density ‘C’ but with the option of a mA or HART Input • Prime selected Header ‘viscosity’ density – from fluid density ‘C’ or ‘D’ or fallback facility

Figure 11.26-1: Header Density Blocks and Parameters

HEADER(VISCOSITY)

DENSITY


DENSITY 'C'Density 'C'Calculation

Apply OtherFactors


PressureCorrection

VOSCorrection

45 6 7 8 9 10 11 12 13 14 15 16 17

18

Density 'D'Calculation

Apply OtherFactors


PressureCorrection

VOSCorrection

24 25 26 27 28 29 30 31 32 33 34 35 37

XX

3

(ρ C)

19Header

ViscositySelection

38

39

DENSITY 'D'37

23

1a2

(μ S)

1bOR

(μ S)

tA (Header) PHeader

(ρ D)

20a21

(μ S)

20bOR

(μ S)

22

PHeadertB (Header)

Menu Navigation List: (1) <“Configure”>/<“Transducer details”>/<Densitometer…> or <“Configure”>/<“Transducer details”>/<Viscometer…> (2) <“Health check”>/<”Inputs”>/<“Time period inputs”>, (3) <“Configure”>/<“Density”>, (4) <“Density”>, (5) <“Temperature”> and (6) <“Pressure”> Menu Data List: * shows data that can be “Live” or “Set”


1a Time period input 3 * (A:1) 20a Time period input 4 * (A:2) 1b Time period input 3b * (A:1) 20b Time period input 4b * (A:2) 2 Time period 3 type A:1 21 Time period 4 type A:2 3 Dens3 glitch limit 22 Dens4 glitch limit 4 Density3 K0 23 Density4 K0 5 Density3 K1 24 Density4 K1 6 Density3 K2 25 Density4 K2 7 Density3 correct C 26 Density4 correct C 8 Density3 K18 27 Density4 K18 9 Density3 K19 28 Density4 K19

10 Density3 K20a B 29 Density4 K20a B 11 Density3 K20b B 30 Density4 K20b B 12 Density3 K21a B 31 Density4 K21a B 13 Density3 K21b B 32 Density4 K21b B 14 Density3 Txdr type 33 Density4 Txdr type 15 Density3 VOS 34 Density4 VOS 16 Density3 offset 35 Density4 offset 17 Dens Meter Factor 3 36 Dens Meter Factor 4 18 DensityC value * 37 DensityD value * 19 Header dens comp lmt 38 Select header visc D

– Flow system type 39 Visc prime density *

Notes are on the next page.



Page 11.56 7955 2540 (CH011/AF)

HEADER ‘VISCOSITY’ DENSITY (1X4X1) CONFIGURATION

Notes: A:1 The “Density” option (value) is for when the fluid density ‘C’ measurement involves a liquid density


The “7827” option (value) is for when the fluid density ‘C’ measurement involves a 7827 viscosity analyser. Live 7827 values will appear in the <“Time Period Input 3b”> menu data page (location) instead of the <“Time Period Input 3”> menu data page (location).

(Chapter 2 features time period input and analogue input rear panel connections)

A:2 The “Density” option (value) is for when the fluid density ‘D’ measurement involves a liquid density



(Chapter 2 features time period input and analogue input rear panel connections) B Not applicable when using 7827 viscosity analysers (viscometers) for the associated density measurement C Various combinations of corrections to density can be selected, as shown in Table 11.18.1 on page 11.41.

Table 11.18.2 then shows the applicability of selected corrections when using different types of transducer.

D This is the same parameter as used when configuring the prime selection of Header viscosity measurements. Consequently, refer to Table 11.26.8 for the select ion logic of Header ‘viscosity’ density.


Table 11.26.8: Logic table for Prime Viscosity Density Selection

Prime Selected Header Viscosity *

Density ‘C’ Live Input Fail ?

Density ‘D’ Live Input Fail ?

Header ‘Viscosity’ Density Selected

“Viscosity A” No No C

“Viscosity A” No Yes C

“Viscosity A” Yes No FAIL

“Viscosity A” Yes Yes FAIL

“Viscosity B” No No D

“Viscosity B” No Yes FAIL

“Viscosity B” Yes No D

“Viscosity B” Yes Yes FAIL

Fallback No No FB

Fallback No Yes FB

Fallback Yes No FB

Fallback Yes Yes FB

“C” = Density ‘C’ (Viscosity density channel ‘A’)

“D” = Density ‘D’ (Viscosity density channel ‘B’)

“FAIL” = No Alternative Source

FB = Fallback

* Monitor selection by viewing the <”Select header visc”> menu data page


7955 2540 (CH011/AF) Page 11.57

11.27 HEADER VISCOSITY FROM 7827 (1X4X1 SCHEME)

Measurements Supported: (Also, see page 11.55 for additional measurements from the same 7827 analysers)

• Dynamic viscosity ‘A’ & ‘B’, Header dynamic viscosity, Kinematic viscosity ‘A’ & ‘B’, Header kinematic viscosity

Figure 11.27-1: Header Viscosity Blocks and Parameters (1x4x1)

KinematicViscosity 'A'

Hysteresis

Q FactorCalculation

1

2

μS

μS3

Q Factor'A'

7827Viscosity

Calculation

4 205


21 2656

27

Hysteresis

Q FactorCalculation

28

29

μS

μS30

Q Factor'B'

7827Viscosity

Calculation

31 4732


48 5357

54

DynamicViscosity 'A'

DynamicViscosity 'B'

KinematicViscosity

Calculation

KinematicViscosity

Calculation

58

58

HeaderViscositySelection

59 6669

HeaderDynamicViscosity

67

68

70

HeaderKinematicViscosity

KinematicViscosity 'B'

MethodSelection

55

mALive Input

Selection

73mA inputs

HART inputs

PT100 inputs

ViscosityCalculation(Scaling)

PT100 or HART

74 75

72

mALiveInput

Selection

77mA inputs

HART inputs

PT100 inputs

ViscosityCalculation(Scaling)

PT100 or HART

78 79

76

55

55

55

71

Menu Navigation List: (1) <“Health Check”>/<“Inputs”>/<”Time period inputs”>, (2) <“Configure”>/<“Transducer details”>/<Viscometer…> (3) <“Health Check”>/<“Viscometer”>, (4) <“Configure”>/<“Viscosity”>/<”Header visc”> (5) <“Viscosity”> (6) <“Configure”>/<“Transducer details”>/<”Flow system type”>


Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 1 Time period input 3 * 28 Time period input 4 * 2 Time period input 3b * 29 Time period input 4b * 3 Q factor visc 3 * MENU(3) 30 Q factor visc 4 * MENU(3) 4 Visc 3 calib ranges 31 Visc 4 calib ranges 5 Visc 3 ultra-low V0 32 Visc 4 ultra-low V0 6 Visc 3 ultra-low V1 33 Visc 4 ultra-low V1 7 Visc 3 ultra-low V2 34 Visc 4 ultra-low V2 8 Visc 3 u-low scale 35 Visc 4 u-low scale 9 Visc 3 low V0 36 Visc 4 low V0

10 Visc 3 low V1 37 Visc 4 low V1 11 Visc 3 low V2 38 Visc 4 low V2 12 Visc 3 low scale 39 Visc 4 low scale 13 Visc 3 medium V0 40 Visc 4 medium V0 14 Visc 3 medium V1 41 Visc 4 medium V1 15 Visc 3 medium V2 42 Visc 4 medium V2 16 Visc 3 medium scale 43 Visc 4 medium scale 17 Visc 3 high V0 44 Visc 4 high V0 18 Visc 3 high V1 45 Visc 4 high V1 19 Visc 3 high V2 46 Visc 4 high V2 20 Visc 3 high scale 47 Visc 4 high scale 21 Visc 3 Hysteresis B 48 Visc 4 Hysteresis B 22 Visc 3 U-low limit 49 Visc 4 U-low limit 23 Visc 3 UL-L switch 50 Visc 4 UL-L switch 24 Visc 3 L-M switch 51 Visc 4 L-M switch 25 Visc 3 M-H switch 52 Visc 4 M-H switch 26 Visc 3 high range 53 Visc 4 high range 27 Dynamic visc A * 54 Dynamic visc B *


Page 11.58 7955 2540 (CH011/AF)

HEADER VISCOSITY (1X4X1 SCHEME) CONFIGURATION


Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 55 Visc noise filter 68 Kinematic visc B * 56 Visc 3 current range 69 Header kin visc * 57 Visc 4 current range 70 Header dyn visc * 58 Visc prime density * 71 Header visc select A 59 Header dyn HI limit 72 Dyn visc B method 60 Header dyn LO limit 73 Dyn visc B mA source 61 Header dyn comp limit 74 Dyn visc B @ 20mA 62 Header Kin HI limit 75 Dyn visc B @ 0/4mA 63 Header Kin LO limit 76 Visc B calc select 64 Viscosity FB type 77 Kin visc B AIN/HART 65 Dyn visc FB value 78 Kin visc B @ 20mA 66 Kin visc FB value 79 Kin visc B @ 0/4mA 67 Kinematic visc A * – Flow system type C

Notes: A The selected option also controls the logic for the prime selection of a ‘viscosity loop’ density channel B A brief guide to the Hysteresis mechanism is shown below C This parameter setting has a significant impact on many other measurements. [MENU(6)] Hysteresis Guide The Flow Computer can use hysteresis to select a calibrated range for the transducer; even if programmed ranges have some overlap. Range identification, even without use of hysteresis, allows the Flow Computer to use the most appropriate set of factors for calculations.

The V0, V1 and V2 factors for each calibrated range are found on the transducer certificate. For further information on calibration ranges, refer to the Technical Manual that was supplied with the transducer.

Hysteresis also avoids continuous switching between calibration ranges when the dynamic viscosity is fluctuating around a calibration range boundary. Example: Calibration Range Identification Consider 1% hysteresis with Viscosity Transducer ‘A’ calibrated for low, medium and high ranges. Work through the numbered calculations with reference to the diagram and table of configuration details associated with hysteresis.

Menu Data (as displayed) Value/Option Ref. Calculated

Boundary Values Visc 3 ultra-low lmt 1 cP - - Visc 3 UL-L switch 10 cP SD 9.9 cP, 10.1 cP Visc 3 L-M switch 100 cP SC 99 cP, 101 cP Visc 3 M-H switch 1000 cP SB 990 cP, 1010 cP Visc 3 high range 12500 cP SA - Visc 3 calib ranges low, med,high - - Visc 3 hysteresis 1% - -

Calculations: 1. Hysteresis boundary point calculations for switching between the

medium and high calibration ranges.

⎟⎠

⎞⎜⎝

⎛ −=100

11*1 BSA ⎟

⎠

⎞⎜⎝

⎛ +=100

11*1 BSB

( )99.0*10001 =A )01.1(*10001 =B

9901 =A 10101 =B

ResultsSwitch to high range from medium range at just over 1010 cP. • Switch to medium range from high range at just under 990 cP.

High RangeA1

B1

DynamicViscosity

(cP)

CalculatedHysteresis

Points

SC

SA

No Calibration Range (Fail)

B2

A2

Medium Range

Hysteresis Band

Hysteresis Band

SB

Low Range

No Calibration Range (Fail)SD

A Zone HysteresisHigh= −⎛

⎝⎜⎞⎠⎟

* 1100

B Zone HysteresisLow= +⎛

⎝⎜⎞⎠⎟

* 1100


7955 2540 (CH011/AF) Page 11.59

HYSTERESIS HEADER VISCOSITY FROM 7827 (1X4X1)

(Calculations continued…)

2. Hysteresis point calculations for switching between medium and low viscosity ranges.

⎟⎠

⎞⎜⎝

⎛ −=100

11*2 CSA ⎟

⎠

⎞⎜⎝

⎛ +=100

11*2 CSB

( )99.0*1002 =A ( )01.1*1002 =B

992 =A 1012 =B

ResultsSwitch to medium range from low range at just over 101 cP. • Switch to low range from medium range at just under 99 cP.

3. Hysteresis point calculations for changes switching low and ultra-low viscosity calibration ranges:

Without an ultra-low calibration range set-up, dynamic viscosity ‘A’ data shows “Fail” on the status line when the calculated value goes below 9.9 cP. The low range remains selected. Once a fail status is shown, dynamic viscosity ‘A’ must go above 10.1 cP to become “Live”.

4. Hysteresis point calculations for changes around the upper limit of the high viscosity calibration range:

The dynamic viscosity ‘A’ menu data shows “Fail” on the status line when the calculated value goes above the high limit - 12,500 cP in the example. The high range remains selected. Once a “fail” status is shown, the dynamic viscosity ‘A’ measurement value must fall below the high limit (12,500 cP) to become “Live” again.

Viscosity Equation List: (Note: Menu data shown is for the viscosity measurement channel ‘A’. For channel ‘B’ parameters, see page 11.57)

Equation VISC#1: Quality factor from a 7827 viscosity analyser

For an example, menu data shown is for viscosity transducer 1.

Using: Q =

⎥⎥

⎦

⎤

⎢⎢

⎣

⎡⎟⎟⎠

⎞⎜⎜⎝

⎛−⎟⎟

⎠

⎞⎜⎜⎝

⎛5.05.0

1

A

B

B

A

ττ

ττ

Where: Q = Quality factor of transducer (no units)…………...……... {Menu Data: <”Q factor visc 3”>}

Aτ = Time period ‘A’ of transducer (μs)…….……….……...… {Menu Data: <”Time period input 3”>}

Bτ = Time period ‘B’ of transducer (μs)……….…….……..…. {Menu Data: <”Time period input 3b”>}

Equation VISC#2: Fluid dynamic viscosity

Using: η = ⎟⎟⎠

⎞⎜⎜⎝

⎛+⎟⎟

⎠

⎞⎜⎜⎝

⎛+

42

11

Q*V

Q*VV 210

Where: η = Fluid dynamic viscosity (cP)……………..………………. {Menu Data: <”Dynamic visc A”>}

0V = Transducer calibration factor V0……..….….…………… {Menu Data: <Visc 3 xxx V0>} *

1V = Transducer calibration factor V1………..……..………… {Menu Data: <Visc 3 xxx V1>} *

2V = Transducer calibration factor V2…………..……..……… {Menu Data: <Visc 3 xxx V2>} *

Q = Quality factor of transducer (no units)…..…..……..…... {Menu Data: <”Q factor visc 3”>}

* The Flow Computer automatically uses values for V0, V1 and V2 from a selected calibrated range.


Page 11.60 7955 2540 (CH011/AF)

11.28 VISCOSITY REFERRAL (1X4X1 SCHEME)

Measurements Supported: • Base kinematic viscosity – for up to four metering-points • Meter kinematic viscosity – for up to four metering-points

Figure 11.28-1: Viscosity Referral Blocks and Parameters (1x4x1)

Index to use with menu data list

ASTM D341ViscosityReferral

84

ν

6985 86 87

XX

80

tMeter

1274xASTM D341

ViscosityReferral

88 103

Curve Points

4x5 MatrixViscosityReferral

104 126

ORReferralBy-pass(On/Off)

128

130 Meter KinematicViscosity

tB

838281

tHead(Visc.)

νHead(Kin.)

69

80

tMeter 81

tHead(Visc.)

νHead(Kin.)

tB

8382

69

80

tMeter 81

tHead(Visc.)

νHead(Kin.)

tBase

82

Multi-Curve Profile

Multi-Curve Profile

69νHead(Kin.)

Base KinematicViscosity

131

132

HI

LO

129

133

134

HI

LO

Menu Navigation List: (1) <“Configure”>/<“Viscosity”>, (2) <“Viscosity”>, (3) <“Configure”>/<“Transducer details”> and (4) <”Temperature”> Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 69 Header kin visc * D 93 ASTM curve2 T2

94 ASTM curve2 visc @ T1

80 Header visc temp * E 95 ASTM curve2 visc @ T2

81 MeterRun temperature * , E 96 ASTM curve3 T1

82 Base temperature * 97 ASTM curve3 T2

83 Absolute zero A 98 ASTM curve3 visc @ T1

84 ASTM temperature T1 99 ASTM curve3 visc @ T2

85 ASTM viscosity @T1 100 ASTM curve4 T1

86 ASTM temperature T2 101 ASTM curve4 T2

87 ASTM viscosity @T2 102 ASTM curve4 visc @ T1

88 ASTM curve1 T1 103 ASTM curve4 visc @ T2

89 ASTM curve1 T2 104 4x5 curve temp T0

90 ASTM curve1 visc @ T1 : : : : :

91 ASTM curve1 visc @ T2 108 4x5 curve temp T4

92 ASTM curve2 T1 109 4x5 curve1 visc @T0

Notes and continued Menu Data List are on the next page


7955 2540 (CH011/AF) Page 11.61

CONFIGURATION VISCOSITY REFERRAL (1X4X1 SCHEME) (Menu Data List continued…) * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 110 4x5 curve1 visc @T1 127 Visc referral method

: : : : : 128 Flow dens/visc sel F 113 4x5 curve1 visc @T4 129 Base kinematic visc *

114 4x5 curve2 visc @T0 130 Meter kinematic visc *

115 4x5 curve2 visc @T1 – Flow system type

: : : : : 131 Mtr Kin visc HI lmt G,

118 4x5 curve2 visc @T4 132 Mtr Kin visc LO kmt G,

119 4x5 curve3 visc @T1 133 Base Kin visc HI lmt G, : : : : : 134 Base visc LO lmt G,

123 4x5 curve3 visc @T4

123 4x5 curve4 visc @T1 : : : : :

126 4x5 curve4 visc @T4


A The value is pre-set to -273.150 degrees centigrade B Kinematic viscosity must exceed 2 cSt for the referral calculation to be performed correctly C This parameter setting has a significant impact on many other measurements. [MENU(3)] D Turn to page 11.57 for information on configuring this viscosity measurement E Turn to pages 11.36 and 11.37 for configuration information. [MENU(4)] F Choose the “Calculation” option when you require a referral of Header viscosity to live metering conditions.

The alternative, “Transducer”, is for when meter kinematic viscosity is to be the same as Header viscosity. G Optional HI and LO alarm limits. Programming these limits with a zero value will avoid maximum and

minimum limit checks on the LIVE value of the associated parameter.


Page 11.62 7955 2540 (CH011/AF)

11.29 METER VISCOSITY (4X4X4 SCHEME) Measurements Supported: (Also, see page 11.50 for additional measurements from the same 7827 analysers) • Meter dynamic viscosity – for up to four metering-points – from 7827 viscosity analysers • Meter kinematic viscosity – for up to four metering-points

Figure 11.29-1: Meter Viscosity Blocks and Parameters (4x4x4)

Hysteresis

MeterKinematicViscosity

Q FactorCalculation

1

2

μs

μs3

Q Factor

7827 ViscosityCalculation

4 20To5


21 2627

32

To

KinematicViscosity

Calculation

28

34

35

35

Limits &FallbackChecks

29

30 3133

νMeter(Dyn)

νMeter(Kin)

ρMeterF/B

HI LO

36 37HI LO

Menu Navigation List: (1) <“Health Check”>/<“Inputs”>/<”Time period inputs”>, (2) <“Configure”>/<“Transducer details”>/<Viscometer…>, (3) <“Health Check”>/<“Viscometer”>, (4) <“Configure”>/<“Viscosity”>/<“4x4x4 viscosity”> and (5) <“Viscosity”>


Menu Data Menu Data Menu Data Menu Data Index

(Metering-point 1) (Metering-point 2) (Metering-point 3) (Metering-point 4) Notes?

1 Time period input 1 * Time period input 2 * Time period input 3 * Time period input 4 * 2 Time period input 1b * Time period input 2b * Time period input 3b * Time period input 4b * 3 Q factor visc 1 * Q factor visc 2 * Q factor visc 3 * Q factor visc 4 * 4 Visc 1 calib ranges Visc 2 calib ranges Visc 3 calib ranges Visc 4 calib ranges 5 Visc 1 ultra-low V0 Visc 2 ultra-low V0 Visc 3 ultra-low V0 Visc 4 ultra-low V0 6 Visc 1 ultra-low V1 Visc 2 ultra-low V1 Visc 3 ultra-low V1 Visc 4 ultra-low V1 7 Visc 1 ultra-low V2 Visc 2 ultra-low V2 Visc 3 ultra-low V2 Visc 4 ultra-low V2 8 Visc 1 u-low scale Visc 2 u-low scale Visc 3 u-low scale Visc 4 u-low scale 9 Visc 1 low V0 Visc 2 low V0 Visc 3 low V0 Visc 4 low V0

10 Visc 1 low V1 Visc 2 low V1 Visc 3 low V1 Visc 4 low V1 11 Visc 1 low V2 Visc 2 low V2 Visc 3 low V2 Visc 4 low V2 12 Visc 1 low scale Visc 2 low scale Visc 3 low scale Visc 4 low scale 13 Visc 1 medium V0 Visc 2 medium V0 Visc 3 medium V0 Visc 4 medium V0 14 Visc 1 medium V1 Visc 2 medium V1 Visc 3 medium V1 Visc 4 medium V1 15 Visc 1 medium V2 Visc 2 medium V2 Visc 3 medium V2 Visc 4 medium V2 16 Visc 1 medium scale Visc 2 medium scale Visc 3 medium scale Visc 4 medium scale 17 Visc 1 high V0 Visc 2 high V0 Visc 3 high V0 Visc 4 high V0 18 Visc 1 high V1 Visc 2 high V1 Visc 3 high V1 Visc 4 high V1 19 Visc 1 high V2 Visc 2 high V2 Visc 3 high V2 Visc 4 high V2 20 Visc 1 high scale Visc 2 high scale Visc 3 high scale Visc 4 high scale 21 Visc 1 Hysteresis Visc 2 Hysteresis Visc 3 Hysteresis Visc 4 Hysteresis 22 Visc 1 U-low limit Visc 2 U-low limit Visc 3 U-low limit Visc 4 U-low limit 23 Visc 1 UL-L switch Visc 2 UL-L switch Visc 3 UL-L switch Visc 4 UL-L switch 24 Visc 1 L-M switch Visc 2 L-M switch Visc 3 L-M switch Visc 4 L-M switch 25 Visc 1 M-H switch Visc 2 M-H switch Visc 3 M-H switch Visc 4 M-H switch 26 Visc 1 high range Visc 2 high range Visc 3 high range Visc 4 high range 27 Visc 1 current range Visc 2 current range Visc 3 current range Visc 4 current range

Index Menu Data (as displayed) Notes?

28 Visc txdr HI limit B, 29 Visc txdr LO limit B, 30 Visc txdr FB type C, 31 Visc txdr FB value (C), 32 Dyn visc txdr value * 33 Density txdr value * 34 Kin visc txdr value * D, 35 Visc noise filter 36 Mtr Kin visc HI lmt B, 37 Mtr Kin visc LO kmt B, – Flow system type E – Meter dens/visc sel A

Notes: Separate location value (and state) for each of four

metering-points but all accessible through the same menu data page

A Select the “Transducer” option for this measurement.

B Optional HI and LO alarm limits for associated measurement

C Optional fallback facility in case of time-period failure

D Turn to page 11.50 for configuration information

E This parameter setting has a significant impact on many other measurements.


7955 2540 (CH011/AF) Page 11.63

11.30 BASE SEDIMENT & WATER MEASUREMENTS

Measurements Supported: (As used in “Net Oil/Water Measurements”) • BSW Analyser Input ‘A’ - from a mA Input • BSW Analyser Input ‘B’ - from a mA Input • Prime BSW Analyser Input

Figure 11.30-1: BS&W Blocks and Parameters

Live InputSelection

4

1

mA InputsBSW

Calculation(Scaling)

%

2 3

8

PrimeSelection

15

10

BSW 'A'

PRIMEANALYSER

BSW

0%100%

9

Live InputSelection

5

mA InputsBSW

Calculation(Scaling)

%

6 70%100%

BSW 'B'

11

12

HI

LO

13 14FB


A#B

16

Menu Navigation List: (1) <“Configure”>/<“Sediment & Water”>/<”Header BSW”>/<”Prime BSW analyser”> (2) <“Configure”>/<“Sediment & Water”>/<”Header BSW”>/<”Prime BSW analyser”>/<”Limits”> (3) <“Sediment & Water”>/<”Header BSW”>/ <”Prime BSW analyser”> Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 1 BSW A input chl A 9 Prime BSW comp limit D

2 BSW A pcent @ 100% 10 Prime BSW select B

3 BSW A pcent @ 0% 11 Head BSW HI limit C

4 BSW A value * 12 Head BSW LO limit C

5 BSW B input chl A 13 Live BS&W FB type

6 BSW B pcent @ 100% 14 Live BS&W FB value

7 BSW B pcent @ 0% 15 Prime BSW analyser *

8 BSW B value * 16 Prime BSW selected

Notes: A Ensure that the basic configuration information of the live input channel has been completed - See page 11.6 B Nominate a logic decision table to be used by the Flow Computer whenever performing a prime measurement

selection. (Also, see page 11.64) C Optional HI and LO alarm limits. Programming the limits with a zero value will avoid maximum and minimum

alarm limit checks on the associated measurement. D Optional comparison alarm limit. Program it with a zero value to avoid a comparison of the two BSW channels.


Page 11.64 7955 2540 (CH011/AF)

BASE SEDIMENT & WATER MEASUREMENTS CONFIGURATION

PRIME SELECTION PROCEDURE In the event of a BSW measurement channel (‘A’ or ‘B’) failing or returning to a live state, the Flow Computer immediately attempts to select an alternative measurement channel for the prime value. The selection procedure simply involves evaluating a user-nominated logic decision table, resulting in a new prime selection.

Table 11.30.1: "Auto BSW A" Option Logic Table for Prime BSW


BSW ‘A’ Input Failed

BSW ‘B’ Input Failed

Prime Selection

No No No A No No Yes A No Yes No B No Yes Yes FB

Yes No No A Yes No Yes A Yes Yes No B Yes Yes Yes FB

Table 11.30.2: "Auto BSW B" Option Logic Table for Prime BSW




Prime Selection

No No No B No No Yes A No Yes No B No Yes Yes FB

Yes No No B Yes No Yes A Yes Yes No B Yes Yes Yes FB

Table 11.30.3: "BSW A" Option Logic Table for Prime BSW




Prime Selection

No No No A No No Yes A No Yes No FB No Yes Yes FB

Yes No No A Yes No Yes A Yes Yes No FB Yes Yes Yes FB

Table 11.30.4: "BSW B" Option Logic Table for Prime BSW




Prime Selection

No No No B No No Yes FB No Yes No B No Yes Yes FB

Yes No No B Yes No Yes FB Yes Yes No B Yes Yes Yes FB


7955 2540 (CH011/AF) Page 11.65

11.31 NET OIL/WATER MEASUREMENTS (1X4X1 SCHEME)Oil/Water Mix Calculations: The “BSW Input Present” Method (Turn to pages 11.67 and 11.69 for other OPTIONS) OPTION ONE is suitable when:

(a) there is a mA type field transmitter providing percentage of ‘water’ (Base Sediment and Water) values, (b) the density of the ‘water’ at base conditions is calculated by the Flow Computer, (c) the density of the oil at base conditions is a known fixed value and (d) the density of the mixture is measured

Header (Indicated) Measurements: • % of oil by volume (calculated) • % of ‘water’ by volume (Live or fixed value) • Density of oil and density of water (calculated) • % of oil by mass (calculated) • % of ‘water’ by mass (calculated) Base Measurements: • Density of oil at base conditions (fixed value) • Density of water at base conditions (calculated)

Figure 11.31-1: Net Oil/ Water Calculations (“BSW Input Present” option)

1% VolumeOil Calc.(Head)

2 % Volume (Oil)

Water DensityCalculation

(Head)

ρHead

(mix) 8

10 11

9Oil DensityReferral Calc.(API or 4x5)

6

4

ρHead(oil)ρBase

(oil)

ρHead (water)

5

5

Oil DensityReferral Calc.(API or 4x5)

7ρMeter(oil)

Water DensityReferral

Calculation

26

28tHead

12ρBase

(water)

10 11A B


Calculation

28

tB

13 ρMeter(water)

27

tMeter

% VolumeCalcs.(Meter)

% Mass (Oil)

% Volume (Oil)

18

ρMeter (Oil) 19

% Volume (Water)% of MassCalculations

% Mass (Water)

% Std. VolumeCalculations

(Meter)

% Std. Vol. (Oil)22

23 % Std. Vol. (Water)

14

15

16HI

17LO

20HI

21LO

24HI

25LO


XX

Prime HeaderBSW Input

3 % Volume ('Water')

ρHead

(mix) 8 % Mass (Oil)

12ρBase (water)

4ρBase (oil)

A B tB

Menu Navigation List: (1) <“Configure”>/<“Sediment & Water”>, (2) <“Configure”>/<“Density”>/<”Net oil/water dens”>, (3) <”Configure”>/<”Base density”>, (4) <“Configure”>/<“Flow rate”>/<”Net oil/water rate”> and (5) <“Temperature”> Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? - Perform net calcs A 12 Base den water (net) * E

- Net calcs type B 13 Line density water * E

1 Prime BSW analyser * E, J 14 Mass water% * E

2 Head volume oil% 15 Mass oil% *

3 Head BSW% 16 Mass water HI limit H 4 Base density oil I 17 Mass water LO limit H

5 Base dens method C 18 Line BSW% * E

6 Header density oil * 19 Line volume oil%

7 Line density oil * 20 Line BSW LO limit H

8 Header dens * D 21 Line BSW HI limit H

9 Header density water * E 22 Std volume oil%

10 Water dens const A MENU(2) 23 Std volume water% *

11 Water dens const B MENU(2) 24 Std vol water LO lmt H

See next page for continued menu data list and applicable notes.

Metering (Line) Measurements: • Base Sediment and Water percentage (calculated) • % of oil by gross volume (calculated) • % of water by gross volume (calculated) • % of oil by standard volume (calculated) • % of water by standard volume (calculated) • Density of oil at metering conditions (calculated) • Density of water at metering conditions (calculated)


Page 11.66 7955 2540 (CH011/AF)

NET OIL/WATER MEASUREMENTS OPTION ONE


Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 25 Std vol water HI lmt H 27 MeterRun temperature * G

26 Header dens temp * F 28 Base temperature

– Flow system type

Notes: Separate location value (and state) for each of four metering-points but all accessible through the same

menu data page A By default, net flow calculations are not enabled. [MENU(4)] B Ensure that the “Water dens calc” multiple-choice option descriptor is selected. [MENU(1)] C Changing the selection of the referral method will also directly affect the configuration for the Meter Density

and Base Density referral calculations. [MENU(3)] D Refer to “Header Density” reference pages for details of configuring to get live values. (Page 11.40) E The Flow Computer will not differentiate between pure water, a water based solution or water with an

impurity F Refer to the “Header Density Temperature“ reference pages for details of this measurement. (Page 11.35) G Refer to the “Meter Temperature“ reference pages for details of this measurement. (Page 11.37) H Optional HI and LO alarm limits. Programming the limits with a zero value will avoid maximum and minimum

alarm limit checks on the associated measurement I A known value must be programmed (SET) into the Flow Computer J Refer to Section 11.30 reference pages for details of configuring this live measurement. (See page 11.63)


7955 2540 (CH011/AF) Page 11.67

OPTION TWO NET OIL/WATER MEASUREMENTS

Oil/Water Mix Calculations: The “BSW Calculated” Method (Turn to pages 11.65 and 11.69 for other options) OPTION TWO is suitable when:

(a) the percentage of ‘water’ (Base Sediment and Water) is not provided by a mA transmitter but is calculated, (b) the density of the ‘water’ at base conditions is a known fixed value, (c) the density of the oil at metering-run conditions is a known fixed value and (d) the density of the mixture is measured

Header (Indicated) Measurements: • % of ‘water’ by volume (calculated) • % of oil by volume (calculated) • Density of the oil (calculated) • Density of the water (calculated) • % of oil by mass (calculated) • % of water by mass (fixed value) Base Measurements: • Density of oil at base conditions (fixed value) and Density of water at base conditions (fixed value)

Figure 11.31-2: Net Oil/Water Calculations (“BSW Calculated” option)


XX

11

10

% Volume (Oil)

Water DensityReferral Calc.

(Head)

ρBase

(water)

69

ρHead(oil)

ρHead (water)

ρMeter(oil)

12LO

13HI


31

ρBase(oil)

2

2


4% Volumeof Oil Calc.

(Head)

5

ρHead(mix)

% Volume (Water)

tHead

27

7 8A B

29

tB

% of MassCalculations

ρHead (water)

% Mass(Water)

% Mass(Oil)

15

16

17HI

18LO

Water DensityReferral Calc.

(Head)

ρBase

(water)

614

ρMeter (water)

tMeter

28

7 8A B

29tB

% VolumeCalculations

(Meter)

% StandardVolume

Calculations(Meter)

1ρBase(oil)

ρBase

(water) 6

% Std. Vol.(Oil)

23

24 % Std. Vol.(Water)

25HI

26LO

% Volume(Oil)

19

20

% Volume(Water)

21HI

22LO

Menu Navigation List: (1) <“Configure”>/<“Sediment & Water”>, (2) <“Configure”>/<“Density”>/<”Net oil/water dens”>, (3) <”Configure”>/<”Base density”>, (4) <“Configure”>/<“Flow rate”>/<”Net oil/water rate”> and (5) <“Temperature”> Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? – Perform net calcs A 9 Header density water * F

– Net calcs type B 10 Head volume oil%

1 Base density oil C 11 Head BSW% F 2 Base dens method D 12 Head BSW LO limit I 3 Line density oil * 13 Head BSW HI limit I 4 Header density oil * 14 Line density water * F 5 Header dens * E 15 Mass oil% 6 Base den water (net) * C, F 16 Mass water% 7 Water dens const A 17 Head BSW LO limit I 8 Water dens const B 18 Head BSW HI limit I

See next page for continued menu data list and associated notes.

Metering (Line) Measurements: • Base Sediment and Water percentage (calculated) • % of oil by gross volume (calculated) • % of water by gross volume (fixed or calculated) • % of oil by standard volume (calculated) • % of water by standard volume (fixed/ or calculated) • Density of oil at line conditions (fixed or calculated)


Page 11.68 7955 2540 (CH011/AF)

NET OIL/WATER MEASUREMENTS OPTION TWO


Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 19 Line BSW% F 25 Std vol water LO lmt I 20 Line volume oil% 26 Std vol water HI lmt I

21 Line BSW LO limit I 27 Header dens temp * G

22 Line BSW HI limit I 28 MeterRun temperature * H

23 Std volume water% F 29 Base temperature

24 Std volume oil% – Flow system type

Notes: A By default, net flow calculations are not enabled. [MENU(4)] B Ensure that the “BSW input present” multiple-choice option descriptor is selected. [MENU(1)] C A known value must be programmed (SET) into the Flow Computer D Changing the selection of the referral method will also directly affect the configuration for the Meter Density and

Base Density referral calculations. [MENU(3)] E Refer to “Header Density” reference pages for details of configuring to get live values. (Page 11.40) F The Flow Computer will not differentiate between pure water, a water based solution or water with an impurity G Refer to the “Header Density Temperature“ reference pages for details of this measurement. (Page 11.35) H Refer to the “Meter Temperature“ reference pages for details of this measurement. (Page 11.37) I Optional HI and LO alarm limits. Programming the limits with a zero value will avoid maximum and minimum

alarm limit checks on the associated measurement.


7955 2540 (CH011/AF) Page 11.69

OPTION THREE NET OIL/WATER MEASUREMENTS

Oil/Water Mix Calculations: “Missing Oil Base Density” option (Turn to pages 11.65 and 11.67 for other options) OPTION THREE is suitable when:

(a) there is a mA type field transmitter providing percentage of ‘water’ (Base Sediment and Water) values, (b) the density of the oil at base conditions is calculated by the Flow Computer, (c) the density of the ‘water’ at base conditions is a known fixed value and (d) the density of the oil/water mix is measured

Header (Indicated) Measurements: • % of oil by volume (calculated) • % of ‘water’ by volume (Live or fixed value) • Density of oil and density of water (calculated) • % of oil by mass (calculated) • % of ‘water’ by mass (calculated)

Base Measurements: • Density of oil at base conditions (calculated) • Density of water at base conditions (fixed value)

Figure 11.31-3: Net Oil/Water Calculations (“Missing Oil Base Density” option)

1% VolumeOil Calc.(Head)

2 % Volume (Oil)

Oil DensityCalculation

(Head)

ρHead

(mix) 8

12ρBase

(water)

Prime HeaderBSW Input

3 % Volume ('Water')

10 11A B


Calculation

28

tBOil Density

Referral Calc.(API or 4x5)

5

26tHead

9ρHead

(water)

5


7 ρMeter(oil)

10 11A B


Calculation

28

tB

27tMeter

13

ρMeter(water)

6

ρHead(oil)

4

ρBase (oil)

% VolumeCalcs.(Meter)

% Mass (Oil)

% Volume (Oil)

18

ρMeter (Oil) 19

% Volume (Water)% of Mass

Calculations

% Mass(Water)

% Std. VolumeCalculations

(Meter)

% Std. Vol. (Oil)22

23 % Std. Vol. (Water)

14

15

16HI

17LO

20HI

21LO

24HI

25LO

ρHead

(mix) 8 % Mass (Oil)

12ρBase(water)

4ρBase(oil)

Index for use with list of associated dataXX

Menu Navigation List: (1) <“Configure”>/<“Sediment & Water”>, (2) <“Configure”>/<“Density”>/<”Net oil/water dens”>, (3) <”Configure”>/<”Base density”>, (4) <“Configure”>/<“Flow rate”>/<”Net oil/water rate”> and (5) <“Temperature”>


Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? - Perform net calcs A 12 Base den water (net) * I ,E

- Net calcs type B 13 Line density water * E 1 Prime BSW analyser * E, J 14 Mass water% * E 2 Head volume oil% 15 Mass oil% * 3 Head BSW% 16 Head BSW LO limit H 4 Base density oil 17 Head BSW HI limit H 5 Base dens method C 18 Line BSW% * E 6 Header density oil * 19 Line volume oil% 7 Line density oil * 20 Line BSW LO limit H 8 Header dens * D 21 Line BSW HI limit H 9 Header density water * E 22 Std volume oil%

10 Water dens const A 23 Std volume water% * 11 Water dens const B 24 Std vol water LO lmt H

See next page for continued menu data list and associated notes.

Metering (Line) Measurements: • % of oil by gross volume (calculated) • % of ‘water’ by gross volume (calculated) • % of oil by standard volume (calculated) • % of water by standard volume (calculated) • Density of oil at metering conditions (calculated) • Density of water at metering conditions (calculated)


Page 11.70 7955 2540 (CH011/AF)

OPTION THREE NET OIL/NET WATER MEASUREMENTS


Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 25 Std vol water HI lmt H 27 MeterRun temperature * G

26 Header dens temp * F 28 Base temperature

Notes: A By default, net flow calculations are not enabled. [MENU(4)] B Ensure that the “Oil dens calc” multiple-choice option (descriptor) is selected. [MENU(1)] C Changing the selection of the referral method will also directly affect the configuration for the Meter Density and

Base Density referral calculations. [MENU(3)] D Refer to “Header Density” reference pages for details of configuring to get live values. (Page 11.40) E The Flow Computer will not differentiate between pure water, a water based solution or water with an impurity F Refer to the “Header Density Temperature“ reference pages for details of this measurement. (Page 11.35) G Refer to the “Meter Temperature“ reference pages for details of this measurement. (Page 11.37) H Optional HI and LO alarm limits. Programming the limits with a zero value will avoid maximum and minimum

alarm limit checks on the associated measurement. I A known value must be programmed (SET) into the Flow Computer J Refer to Section 11.30 reference pages for details of configuring this live measurement. (See page 11.63)


7955 2540 (CH011/AF) Page 11.71

11.32 NET FLOW BY METERING-POINT (1X4X1 SCHEME)

Measurements Supported: • Net ‘Water’ Volume flow rate and totals • Net ‘Water’ Standard Volume flow rate and totals • Net ‘Water’ Mass flow rate and totals

• Net Oil Volume flow rate and totals • Net Oil Standard Volume flow rate and totals • Net Oil Mass flow rate and totals

Note: Ensure that Net Oil/Water Measurements, Flow Rates and Flow Totals are configured

Figure 11.32-1: Net ‘Water’ Flow Rates and Metering-run Totals

NVWaterRate

Net WaterVolume FlowRate Calc.

32

27

1% Volume (Water)

QGV

Net WaterStd. Volume

Flow Rate Calc.

ρ Line(Water)

10

ρ Base(Water)

1112

NSVWaterRate

Net WaterMass FlowRate Calc.

ρ Line(Water) 10

19 NMWaterRate


25

24

22

Mode

Flow Totaliser(Normal mode)

23

20 21


18

17

15

Mode

26 Flow Totaliser(Normal mode)

16

13 14


9

8

6

Mode


7

4 5

NSVWaterTotals

NMWaterTotals

NVWaterTotals

26

27

27

Figure 11.32-2: Net Oil Flow Rates and Metering-run Totals


XX

NVOilRateNet Oil

Volume FlowRate Calc.

292

27

28% Volume (Oil)

QGV

Net OilStd. Volume

Flow Rate Calc.

ρ Line(Oil)

36

ρ Base(Oil)

3738

NSVOilRate

Net OilMass FlowRate Calc.

ρ Line(Oil) 36

45 NMOilRate


51

50

48

Mode


49

46 47


44

43

41

Mode


42

39 40


35

34

32

Mode


33

30 31

NSVOilTotals

NMOilTotals

NVOilTotals

26

27

27


Page 11.72 7955 2540 (CH011/AF)

NET FLOW BY METERING-POINT (1X4X1) CONFIGURATION Menu Navigation List:

(1) <“Configure”>/<“Flow rate”>/<”Net oil/water rate”>, (2) <“Flow rates”>/<”MeterRun flowrates”>, (3) <“Configure”>/<“Totalisation”>/<”Standard”>, (4) <“Health check”>/<”Totals”>, (5) <“Flow totals”>/<”Meter run totals”>


Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 1 Line BSW% * 27 Rate flowstop action

2 Gross vol rate * 28 Line volume oil%

3 Water vol rate * 29 Oil vol rate * 4 Water volume roll C 30 Oil volume roll C 5 Water volume inhibit 31 Oil vol inhibit 6 Water volume inc B 32 Oil volume inc B 7 Water volume total A 33 Oil volume total A 8 Maint NV water inc B 34 Maint NV oil inc B 9 Maint NV water total A 35 Maint NV oil total A

10 Line density water * 36 Line density oil * 11 Base density water * 37 Base density oil *

12 Water std vol rate * 38 Oil std vol rate * 13 Water std vol roll C 39 Oil std vol roll C 14 Water std vol inhib 40 Oil std vol inhibit 15 Water std vol inc B 41 Oil std vol inc B 16 Water std vol total A 42 Oil std vol total A 17 Maint NSV water inc B 43 Maint NSV oil inc B 18 Maint NSV water totl A 44 Maint NSV oil total A

19 Water mass rate * 45 Oil mass rate * 20 Water mass roll C 46 Oil mass roll C 21 Water mass inhibit 47 Oil mass inhibit 22 Water mass inc B 48 Oil mass inc B 23 Water mass total A 49 Oil mass total A 24 Maint NM water inc B 50 Maint NM oil inc B 25 Maint NM water total A 51 Maint NM oil total A

26 Flow status , D

Notes: = Separate location for each metering-run A A total value is the integration of a specific parameter value (e.g. metering-run flow rate) over a period of time.

The 7955 updates a total with a new increment value every cycle instead of an integration calculation. B An increment is a calculated value that is then immediately added to the corresponding total. This action is

performed by the 7955 once every machine cycle. Editing an increment value has no affect.

The calculation performed is Increment = (Parameter * t) where the time ‘t’ is the ‘pulse sample time’. C By default, rollover (to zero) limits are ‘SET’ to a very large number. However, it is advisable to check that the

limit is sufficient for the metering application. D There are two Flow Computer modes to be aware of:

1. Normal-mode

In this mode, a main total (e.g. <”Water volume total”>) can increment. The twinned maintenance-mode total (e.g. <”Maint NV water total”>) will never increment.

2. Maintenance-mode In this mode, a maintenance-mode total (e.g. <”Maint NV water total”>) can increment. The twinned normal-mode total (e.g. <”Water volume total”>) will never increment.

A mode can be selected for an individual metering-point. However, the selection can only be performed when the 7955 is in a ‘Flow Stopped’ state for the metering-point concerned.


7955 2540 (CH011/AF) Page 11.73

11.33 NET FLOW BY STATION (1X4X1 SCHEME)

Measurements: • Net ‘Water’ Volume station flow rate and totals • Net ‘Water’ Standard Volume station flow rate and totals • Net ‘Water’ Mass station flow rate and totals

• Net Oil Volume station flow rate and totals • Net Oil Standard Volume station flow rate and totals • Net Oil Mass station flow rate and totals

Note: Ensure that Net Oil/Water Metering-run Flow Rates and Flow Totals are configured

Figure 11.33-1: Net Station Flow Rates and Totals


55 56STATION TOTAL57

STATIONFLOWRATE

52 Add/SubMetering-point

METERING-POINTFLOW RATE

53

54

Menu Navigation List: (1) <“Flow rates”>/<”Station flowrates”>/<”Net oil/water rate”>, (2) <“Configure”>/<“Totalisation”>/<”Station totals”>, (3) <“Health check”>/<”Totals”> and (4) <“Flow totals”>/<”Station totals”>/<”Net oil & water”>

Note: Water Station features and Oil Station features operate in parallel. Simply work through each menu list.

‘Water’ Flow Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Menu Data (as displayed) Menu Data (as displayed) Notes? 52 Water vol rate * Water std vol rate * Water mass rate * 53 Station totalise Station totalise Station totalise 54 Stn water vol rate Stn water stvol rate Stn water mass rate * 55 Stn water vol roll Stn water stdvol roll Stn water mass roll 56 Stn water vol inhib Stn water stdvol inh Stn water mass inhib 57 Stn water vol total Stn water stvol tot Stn water mass total

Oil Flow Menu Data List: * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Menu Data (as displayed) Menu Data (as displayed) Notes? 52 Oil vol rate * Oil std vol rate * Oil mass rate * 53 Station totalise Station totalise Station totalise 54 Stn oil vol rate Stn oil std vol rate Stn oil mass rate 55 Stn oil vol roll Stn oil std vol roll Stn oil mass roll 56 Stn oil vol inhib Stn oil std vol inh Stn oil mass inhib 57 Stn oil vol total Stn oil std vol total Stn oil mass total

Notes: = Separate location for each metering-run A A total value is the integration of a specific parameter value (e.g. station flow rate) over a period of time. The

7955 updates a total with a new increment value every cycle instead of an integration calculation. B An increment is a calculated value that is then immediately added to the corresponding total. This action is

performed by the 7955 once every machine cycle.

The calculation performed is Increment = (Parameter * t) where the time ‘t’ is the ‘pulse sample time’. C By default, rollover (to zero) limits are ‘Set’ to a very large number. However, it is advisable to check that the

limit is sufficient for the metering application.


Page 11.74 7955 2540 (CH011/AF)

NET OIL/NET WATER EQUATIONS

Net oil and water equations: (Listed equations do not conform to a Standard unless otherwise stated) Equation NC#1: Net Oil Volume Flow Rate

Using: NVOil =QOil

GVLine*

%

100

Where: NVOil = Net Oil Volume flow rate…………………….……..………. {Menu data: <”Oil vol rate”>}

QGV = Gross Volume flow rate……………………….………….… {Menu data: <”Gross vol rate”>}

Oil Line% = Percentage of oil flowing through a metering-run……..... {See Equation NC#7b}

Equation NC#2: Net ‘Water’ Volume Flow Rate

Using: NVWater =QWater

GVLine*

%

100

Where: NVWater = Net Oil Volume flow rate………………………..…….….. {Menu data: <”Water vol rate”>}

QGV = Gross Volume flow rate…………………………….….… {Menu data: <”Gross vol rate”>}

Water Line% = Percentage of water flowing through a metering-run.... {See Equation NC#8c}

Equation NC#3: Net Oil Standard Volume Flow Rate

Using: NSVOil = NVOilOilLine

OilBase*

ρ

ρ

Where: NSVOil = Net Oil Standard Volume flow rate………..…..………….. {Menu data: <”Oil std vol rate”>}

NVOil = Net Oil Volume flow rate………..……....…………...…….. {See Equation NC#1 on page 11.74}

ρOilLine = Density of the oil in the metering-run….…….…....……… {Menu data: <”Line density oil”>}

ρOilBase = Density of the oil at base conditions……………. ……..... {Menu data: <”Base density oil”>}

Equation NC#4: Net ‘Water’ Standard Volume Flow Rate

Using: NSVWater = NVWaterWaterLine

WaterBase*

ρρ

Where: NSVWater = Net ‘Water’ Standard Volume flow rate….….……………. {Menu data: <”Water std vol rate”>}

NVWater = Net ‘Water’ Volume flow rate………..……..……...…….... {See Equation NC#2 on page 11.74}

ρWaterLine = Density of the ‘water’ in the metering-run ……......……… {See Equation NC#9c on page 11.77}

ρWaterBase = Density of the ‘water’ at base conditions …………..…..... {See Equation NC#9d on page 11.77}

Equation NC#5: Net oil Mass Flow Rate

Using: NMOil = NVOil OilLine* ρ

Where: NMOil = Net oil mass flow rate…………………………………………… {Menu Data: <”Oil mass rate”>}

NVOil = Net Oil Volume flow rate……………………………………….. {See Equation NC#1 on page 11.74}

ρOilLine = Density of the oil in the metering-run….…….…..…….……… {Menu data: <”Line density oil”>}


7955 2540 (CH011/AF) Page 11.75

NET OIL/NET WATER MEASUREMENTS (EQUATIONS)

Net oil and water equations continued… (Listed equations do not conform to a Standard unless otherwise stated)

Equation NC#6: Net Water Mass Flow Rate

At the metering point:

Using: NMWater = NVWater WaterLine* ρ

Where: NMWater = Net water mass flow rate……….……………………..…… {Menu Data: <”Water mass rate”>}

NVWater = Net ‘water’ volume flow rate…..…………………….…….. {See Equation NC#2 on page 11.74}

ρWaterLine = Density of the ‘water’ in the metering-run….……..……… {See Equation NC#9c on page 11.77}

Equation NC#7: Percentage of oil by volume

At the Header: Using: Oil Head% = (100 - Water Head% )……………………………………. NC#7a

Where: Oil Head% = Percentage of oil flowing through the Header………. {Menu data: <”Head volume oil%”>}

Water Head% = Percentage of ‘water’ flowing through the Header….. {See Equation NC#8 on page 11.75}

At the metering point: Using: Oil Line% = (100 - Water Line% )…………………………………….. NC#7b

Where: Oil Line% = Percentage of oil flowing through a metering-run…… {Menu data: <”Line volume oil%”>}

Water Line% = Percentage of ‘water’ flowing through a metering-run.{See Equation NC#8c on page 11.76}

Equation NC#8: Percentage of ‘water by volume

Note: This measurement is also known as ‘Base Sediment and Water’.

At the Header: Equation NC#8a is applicable when the “Calc. water density” option is selected.

Using: Water Head% = BS W BS W

BS W BS WMax MinIn Min

& % & %* & % & %

−⎛⎝⎜

⎞⎠⎟

+100

………NC#8a

Where: Water Head% = Percentage of ‘water’ flowing through the Header... {Menu Data: <”Head BSW%”>}

BSW In% = Reading from transmitter…………………………….. {Menu Data: <”BS&W value”>}

BSW Max% = Maximum percentage from transmitter…………….. {Menu Data: <”BS&W pcent @ 100%”>}

BSW Min% = Minimum percentage from transmitter……………… {Menu Data: <”BS&W pcent @ 0%”>}

Equation NC#8b is applicable when the “Calc BSW” option is selected.

Using: Water Head% = ( )( )ρ ρ

ρ ρ

MixHead

OilHead

WaterHead

OilHead

−

−*100 …….NC#8b

Where: Water Head% = Percentage of ‘water’ flowing through the Header….. {Menu Data: <”Head BSW%”>}

ρMixHead = Density of the oil/water mixture at the Header………. {Menu Data: <”Header dens”>}

ρOilHead = Density of the oil at the Header……………………….. {Menu Data: <”Header density oil”>}

ρWaterHead = Density of the ‘water’ at the Header….……………….. {See Equation NC#9 on page 11.76}


Page 11.76 7955 2540 (CH011/AF)


Net oil and water equations continued… (Listed equations do not conform to a Standard unless otherwise stated) (Equation NC#8 continued…)

Note: This measurement is also known as ‘Base Sediment and Water’.


Using: Water Line% =( )( )ρ ρ

ρ ρ

MixHead

OilLine

WaterLine

OilLine

−

−* 100 …………………………………… NC#8c

Where: Water Line% = Percentage of ‘water’ flowing at a metering-run…….. {Menu Data: <”Line BSW%”>}

ρOilLine = Density of the oil in the metering-run…………………. {Menu Data: <”Line density oil”>}

ρWaterLine = Density of the ‘water’ in the metering-run……………. {See Equation NC#9c on page 11.77}

And: ρMixHead = ( ) ( ) ( )

100

100

* *

* % * % *

ρ ρ

ρ ρ ρOilLine

WaterLine

OilLine

Oil OilLine

Oil WaterLineMass Mass− +

Where: ρOilLine = Density of the oil in the metering-run………..….……. {Menu Data: <”Line density oil”>}

ρWaterLine = Density of the ‘water’ in the metering-run……..…..…. {Menu Data: <”Line density water”>}

Mass Oil% = Percentage of oil (by mass) in the metering-run….… {See Equation NC#11 on page 11.77}

Equation NC#9: Water Density

At the Header:

Equation NC#9a is applicable when the “Calc water density” option is selected.

Using: ρWaterHead =

( )( )100 *

%

ρ ρρ

MixHead

OilHead

HeadOilHead

Water

−+ ……NC#9a

Where: ρWaterHead = Density of the ‘water’ at the Header……..………………….. {Menu Data: <”Header density water”>}

ρMixHead = Density of the oil/water mixture at the Header………………{Menu Data: <”Header dens”>}

ρOilHead = Density of the oil mixture at the Header…………………….. {Menu Data: <”Header density oil”>}

Equation NC#9b is applicable when the “Calc BSW” option is selected.

Using: ρWaterHead = ( ) ( )ρ δ δ δWater

Base A t B t t− −* * * ……NC#9b

Where: ρWaterHead = Density of the ‘water’ at the Header……..………………….. {Menu Data: <”Header density water”>}

ρWaterBase = Density of the ‘water’ at base conditions…………………… {See Equation NC#9d on page 11.77}

A = Water density constant ‘A’……………………….………….. {Menu Data: <”Water dens const A”>}

B = Water density constant ‘B’……………………….………….. {Menu Data: <”Water dens const B”>}

And: δt = ( )t tHead Base−

Where: tHead = Temperature of the oil/water mixture at the Header….…… {Menu Data: <”Header dens temp”>}

tBase = Base temperature…………………………………………….. {Menu Data: <”Base temperature”>}


7955 2540 (CH011/AF) Page 11.77


Net oil and water equations continued… (Listed equations do not conform to a Standard unless otherwise stated) (Equation NC#9 ‘Water’ Density continued…)


Using: ρWaterLine = ( ) ( )ρ δ δ δWater

Base A t B t t− −* * * ……NC#9c

Where: ρWaterLine = Density of the ‘water’ at a Metering-run...………………….. {Menu Data: <”Line density water”>}

ρWaterBase = Density of the ‘water’ at base conditions…………………… {See Equation NC#9d on page 11.77}

A = ‘Water’ density constant ‘A’…………………….………….. {Menu Data: <”Water dens const A”>}

B = ‘Water’ density constant ‘B’…………………….………….. {Menu Data: <”Water dens const B”>}

And: δt = ( )t tLine Base−

Where: tLine = Temperature of the oil/water mixture at a Metering-Run…. {Menu Data: <”MeterRun temperature”>}


At base conditions:

Equation NC#9d is applicable when the “Calc water density” option is selected.

(Density of the ‘water’ at base conditions must be a ‘Set’ (fixed) value when using the “Calc BSW option)

Using: ρWaterBase = ( ) ( )ρ δ δ δWater

Head A t B t t+ +* * * ……NC#9d

Where: ρWaterBase = Density of the ‘water’ at base conditions..………………….. {Menu Data: <”Base density water”>}

ρWaterHead = Density of the ‘water’ at the Header………………………… {See Equation NC#9a or NC#9b}

A = ‘Water’ density constant ‘A’…………………….……………. {Menu Data: <”Water dens const A”>}

B = ‘Water’ density constant ‘B’…………………….……………. {Menu Data: <”Water dens const B”>}

And: δt = ( )t tHead Base−

Where: tHead = Temperature of the oil/water mixture at the Header………. {Menu Data: <”Header dens temp”>}


Equation NC#10: Percentage of mass (‘water’)

Using: Mass Water% = ( )

( )ρ ρ ρ

ρ ρ ρ

WaterHead

MixHead

OilHead

MixLine

WaterHead

OilHead

*

**

−

−100

Where: Mass Water% = Percentage of ‘water’ (by mass) flowing in system.. {Menu Data: <”Mass water%”>}

ρWaterHead = Density of the ‘water’ at the Header………………… {See Equation NC#9a or NC#9b}

ρMixHead = Density of the oil/water mixture at the Header…….. {Menu Data: <”Header dens”>}

ρOilHead = Density of the oil mixture at the Header……………. {Menu Data: <”Header density oil”>}

Equation NC#11: Percentage of mass (‘oil’)

Using: Mass Oil% = ( )100 − Mass Water%

Where: Mass Oil% = Percentage of mass for oil flowing in system……. {Menu Data: <”Mass oil%”>}

Mass Water% = Percentage of mass for ‘water’ flowing in system.. {See Equation NC#10 on page 11.77}


Page 11.78 7955 2540 (CH011/AF)


Net oil and water equations continued… (Listed equations do not conform to a Standard unless otherwise stated) Equation NC#12: Percentage of standard volume (‘water’)

Using: StdVol Water% = 100

1+⎛

⎝⎜⎜

⎞

⎠⎟⎟

⎛

⎝⎜⎜

⎞

⎠⎟⎟

⎛

⎝

⎜⎜

⎞

⎠

⎟⎟

MassMass

Oil

OilBase

WaterBase

Water

%*

%ρ

ρ

Where: StdVol Water% = Percentage of standard volume for the ‘water’….. {Menu Data: <”Std volume water%”>}

Mass Oil% = Percentage of mass for the oil..…………………… {See Equation NC#11 on page 11.77}

Mass Water% = Percentage of mass for the ‘water’……………….. {See Equation NC#10 on page 11.77}

ρOilBase = Density of the oil at base conditions…………....... {Menu data: <”Base density oil”>}

ρWaterBase = Density of the ‘water’ at base conditions …………{See Equation NC#9d on page 11.77}

Equation NC#13: Percentage of standard volume (oil)

Using: StdVol Oil% = ( )100 − StdVol Water%

Where: StdVol Oil% = Percentage of standard volume for the oil………..{Menu Data: <”Std volume oil%”>}

StdVol Water% = Percentage of standard volume for the ‘water’…..{See Equation NC#12 on page 11.78}

Equation NC#14: Specific gravity for the oil

Using: SGOil =ρ

ρOilBase

WaterBase

⎛

⎝⎜⎜

⎞

⎠⎟⎟

Where: SGOil = Specific gravity for the oil………………………….. {Menu data: <”Oil specific gravity”>}

ρOilBase = Density of the oil at base conditions…………....... {Menu data: <”Base density oil”>}

ρWaterBase = Density of the ‘water’ at base conditions …………{See Equation NC#9d on page 11.77}

Equation NC#15: Degrees API (oil)

Using: APIOilo =

14151315

..

SGOil

⎛

⎝⎜

⎞

⎠⎟ −

Where: APIOilo = Degrees API for the oil…………………………….. {Menu Data: <”Oil degrees API”>}

SGOil = Specific gravity for the oil…………………….……. {See Equation NC#14 on page 11.78}


7955 2540 (CH011/AF) Page 11.79

11.34 INTERFACE DETECTION

Features: • Product Detection (using measurement zoning)

• Product Totals (Gross Volume, Gross Standard Volume and Mass totals for up to 20 products)

1x4x1 Scheme: 8

A maximum of 1 product can flow in all 4 metering runs. This means that 1 set of product totals can increment at any one time.

4x4x4 Scheme: 9

A maximum of 4 products (1 in each meter run) can flow in all 4 metering runs. This means that up to 4 sets of product totals can be incrementing at the same time.

Figure 11.34-1: Interface Detection Blocks and Parameters

Product 1Profile

1ZoneType

Selection

2

5

ProductDetection

16

7 8 9 10 11

1312 14

Product 2 profile : : :Product 20 profile

15

318

6 26

4DEGREES API

HEADER DENSITY (mA)

METER RUN DENSITY

SPECIFIC GRAVITY

27

Product 1 Totalising(Gross Volume)

Product 1 Totalising(Gross Volume)

Product 1Totalising(Corrected Mass)

21

23

25

28 19 20

To Other Sets ofProduct Totals

28 19 22

28 19 24

1729

Menu Navigation List: (1) <“Configure”>/<“Product Detect”>, (2) <“Density”>, (3) <“Flow rates”>/<“MeterRun flowrates”>, (4) <“Flow totals”>/<“Product totals”> and (5) <”Configure”>/<”Transducer details”>/<”Flow system type”>


Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 1 Meter run density * 17 Prod1 dens Txdr FB A, E

2 Base density * 18 Product time delay C

3 SG Value * 19 Current Product ID * 4 Head analog dens * B 20 Product totalisation D

5 Degrees API * 21 Gross vol rate * 6 Product zone type I 22 Product 1 GV total D

7 Band hysteresis 23 Gross std vol rate * 8 Product 1 name A 24 Product 1 GSV total D

9 Product 1 Band HI A 25 Mass rate * 10 Product 1 Band LO A 26 Product 1 Mass total D 11 Prod1 MF A, E, F 27 Non-Band product ID G 12 Prod1 K factor A, E, F 28 Product auto config H 13 Prod1 dens calc sel A, E 29 Reset totalisers

14 Prod1 API product A, E 30 Meter curve type (E),

15 Prod1 API range A, E - Flow system type 16 Prod1 Prime dens FB A, E

Notes: Separate database location (value and state) for each of four metering-points but all accessible through the

same menu data page

8 1x4x1 - an installation with a header that splits into 4 streams and then re-forms a single outlet stream. 9 4x4x4 - an installation without a header. There are 4 streams in and 4 streams out.


Page 11.80 7955 2540 (CH011/AF)

INTERFACE DETECTION CONFIGURATION

A A maximum of 20 product profiles can be defined. The Menu Data shown is a part of the profile for product one. Profile Menu Data of other products are not shown in the schematic or list for reasons of clarity. Each product profile has a corresponding set of product totals.

B (1x4x1 Scheme Only). This is for fluid density measurements from a mA-type field transmitter at the header.

Values are used as advanced notification of a product change. (Also, see note ‘C’) C (1x4x1 Scheme Only). This is a settable fixed period for a product change at the header to reach the turbine.

Product switching should not occur until the fluid reaches a turbine. (Also, see note ‘B’) D Product totalising can be switched on and off with this parameter. Once switched off, increments for totals

are discarded.

1x4x1 (Header) Scheme:

• 7955 will calculate increments for all meter-runs and then update one set of product totals

4x4x4 (Non-Header) Scheme:

• For each product detected, the 7955 will calculate increments for all applicable meter-runs and then update the appropriate set of product totals.

E This data is a part of the Automatic Product Configuration feature. The ‘Set’ value can be copied to the

relevant prime parameter whenever the product is detected.

• For example, the value ‘Set’ for <“Prod1 MF”> would overwrite the value of <“Meter Factor”> as soon as Product #1 is detected, but only if the ‘Meter Factor’ is not being linearised.

• Similarly, the value ‘Set’ for <“Prod1 K factor”> would overwrite the value of <“Flowmeter K Factor”> as soon as Product #1 is detected, but only if the ‘K-factor’ is not being linearised.

(See “Turbine Flow” reference pages for use of <“Meter Factor”>) F Retrospective total calculations can be performed to compensate for changes to the ‘Meter Factor’ or the

‘K-factor’. Specify the volume to be considered when correcting totals. G One set of product totals can be allocated to all fluids that are outside the defined product bands. High and

low band data in the selected product profile are not applied. H Enables or prevents the re-configuring of parameters associated with values from the profile of a detected

product. (Also, see note ‘E’) I Selecting a new zone type will automatically re-select the appropriate base units of measurement for data

listed in all 20 product profiles. Example 1: 4x4x4 Scheme

This example shows density zoning with 4 defined products (i.e. 4 bands)


Drawing Ref.

‘SET’ Value

Product 1 Band High DF -

Product 1 Band Low DE -

Product 2 Band High DE -

Product 2 Band Low DD -

Product 3 Band High DD -

Product 3 Band Low DC -

Product 4 Band High DA -

Product 4 Band Low D0 -

Band hysteresis - 0%

• Product 1 totals increment between time T5 to T8. (Streams 1 and 2 are involved at different times) • Product 2 totals increment between time T7 and TN. (Streams 1 and 2 are involved at different times)

Meter-Run 3MeterRun 2Meter-Run 1

DA

D0

Density(Kg/m3)

Time

DF

Product 1

Product 2

Product 3

Product 4

No Product (Slops)

No Product (Slops)

DE

DD

DC

DB

T0 T1 T2

No Product (Slops)

Meter-run 4

TNT3T4

T5 T6T7 T8


7955 2540 (CH011/AF) Page 11.81

CONFIGURATION INTERFACE DETECTION

(Example 1 continued…)

• Product 3 totals do not increment.

• Product 4 totals increment between time T1 to T2 and T3 to TN. • “Non-product” totals increment at various times:

T0 to T5 (Stream 1), T0 to T6 (Stream 2), T0 to T1 and T2 to T3 (Stream 4).

Example 2: 1x4x1 Scheme

This shows density zoning with 4 defined products (i.e. 4 back-to-back bands)


Drawing Ref.

‘SET’ Value

Product 1 Band High DF -

Product 1 Band Low DE -

Product 2 Band High DE -

Product 2 Band Low DD -

Product 3 Band High DD -

Product 3 Band Low DC -

Product 4 Band High DA -

Product 4 Band Low D0 -

Band hysteresis - 0%

• Product 1 totals increment between time T1 and T2. • Product 2 totals increment between time T2 and T3. • Product 3 totals increment between time T3 and T4. • Product 4 totals do not increment. • “Non-product” totals increment between times T0 to T1 and T4 to TN.

Hysteresis - with overlapping product bands

Hysteresis overcomes the difficulties when products overlap by a small amount.


Figure Ref.

‘SET’ Value

Hysteresis Calc. Value

Product 1 Band High DA 1000 1010.00

Product 1 Band Low DB 795 802.95

Product 2 Band High DB 795 787.05

Product 2 Band Low DC 595 600.95

Band hysteresis - 1% -

1. Hysteresis point calculations when product one is current

detected product

⎟⎠

⎞⎜⎝

⎛ −=100

11*1 ADA ⎟

⎠

⎞⎜⎝

⎛ +=100

11*1 BDB

( )999.0*10001 =A ( )01.1*7901 =B

0.9901 =A 95.8021 =B

• Switch (up) to product 1 from product 2 at just over 802.95 Kg/m3. • Switch (up) to non-product takes place at just over 1010 Kg/m3. • Switch (down) to product 1 from non-product is at exactly 1000 Kg/m3. (The 990 Kg/m3 point is ignored)

Runs 1, 2, 3 & 4

DA

D0

Density(Kg/m3)

Time

DF

Product 1

Product 2

Product 3

Product 4

No Product (Slops)

No Product (Slops)

DE

DD

DC

DB

T0

T1 T2

No Product (Slops)

TN

T3

T4

Product 1A1

B1

Product 2

Product 1 and 2 overlap

Density(Kg/m3)

A Zone HysteresisHigh= −⎛

⎝⎜⎞⎠⎟

* 1100

B Zone HysteresisLow= +⎛

⎝⎜⎞⎠⎟

* 1100

CalculatedHysteresis

Points

Product 2 and 3 overlapDC

DA

DB

No Product

B2

A2


Page 11.82 7955 2540 (CH011/AF)

INTERFACE DETECTION 2. Hysteresis band calculations when product two is current detected product:

⎟⎠

⎞⎜⎝

⎛ +=100

11*2 BDA ⎟

⎠

⎞⎜⎝

⎛ −=100

11*2 CDB

( )99.0*7952 =A ( )01.1*5952 =B

05.7872 =A 95.6002 =B

• Switch (down) to product 2 from product 1 at just under 787.05 Kg/m3.


7955 2540 (CH011/AF) Page 11.83

11.35 LIVE ANALOGUE OUTPUTS

Feature: • Analogue outputs supported by 7955: mA output channels 1 to 8

What to do: Use this reference page to find out how to configure the analogue output channels that are to transmit values to external devices once every machine cycle. By default, no parameters are pre-allocated to the analogue outputs. After configuring, check that a satisfactory live reading is displayed by the <mA output value> menu data page.

Menu Navigation List: (1) <“Configure”>/<“Outputs”>/<”mA outputs”> and (2) <“Health check”>/<“Outputs”>/<”mA outputs”>






mA output 1 value * mA output 5 value * mA output 1 ptr list mA output 5 ptr list mA 1 param val @100% mA 5 param val @100% mA 1 param val @0% mA 5 param val @0% mA output 1 type mA output 5 type mA output 1 filter mA output 5 filter

Analogue Output 1 (mA only)

mA output 1 source

Analogue Output 5 (mA only) **

mA output 5 source mA output 2 value * mA output 6 value * mA output 2 ptr list mA output 6 ptr list mA 2 param val @100% mA 6 param val @100% mA 2 param val @0% mA 6 param val @0% mA output 2 type mA output 6 type mA output 2 filter mA output 6 filter


mA output 2 source




mA output 3 source




mA output 4 source


mA output 8 source

Note: ** Requires MENU (1):<”Available channels”> parameter edited to show a value of “8” A The <mA output source> menu data is for selecting a parameter that is not readily available with the normal

<mA output ptr list> menu data. It is necessary to select the “USER” option descriptor for <mA output ptr list> and then program <mA output source> with the parameter’s unique identification number.

B Filter option = Normal: The new analogue output value is generated immediately.

Filter option = Average: The previous 6 readings are inspected, and the highest and lowest values are ignored, then an average is taken of the 4 remaining readings. The new analogue output value is the average.

Filter option = Oversample: The analogue output value is increased or decreased in equal steps every 100ms over the period set by the 7955 target-cycle-time parameter.

Note: During filtering, the analogue output location changes immediately. It is the analogue output current that changes over time until the final value is achieved.


Page 11.84 7955 2540 (CH011/AF)

11.36 DIGITAL OUTPUTS

Features: • Digital Outputs supported by the 7955

Status output channels 1 to 25 What to do:

This reference page will assist when configuring basic data (see list below) for all the Status Output channels that are being used. Later tasks will expect this menu data to be already configured. By default, the first 5 Status Outputs are reserved for the Alarm Logger Output feature. (See Chapter 8) The remaining outputs are available for use as listed in the connection list of Chapter 3. In the <“Health Check”> menu there is a Status Output sub-menu. It contains a menu data page with a series of digits on the second display line. Each digit indicates the present state of an individual output.

Menu Navigation List: (1) <“Configure”>/<”Outputs”>/<“Status outputs”> and (2) <“Health check”>/<”Outputs”>/<“Status outputs”> Menu Data List: * shows data that can be “Live” or “Set”

Status O/P Channel


Status O/P Channel


Status O/P Channel


1 Status out 1 logic 10 Status out 10 logic 19 Status out 19 logic 2 Status out 2 logic 11 Status out 11 logic 20 Status out 20 logic 3 Status out 3 logic 12 Status out 12 logic 21 Status out 21 logic 4 Status out 4 logic 13 Status out 13 logic 22 Status out 22 logic 5 Status out 5 logic 14 Status out 14 logic 23 Status out 23 logic 6 Status out 6 logic 15 Status out 15 logic 24 Status out 24 logic 7 Status out 7 logic 16 Status out 16 logic 25 Status out 25 logic 8 Status out 8 logic 17 Status out 17 logic 9 Status out 9 logic 18 Status out 18 logic

General Note: A Digital Outputs 1 to 3 are permanently reserved for use by the Alarm Logger Output feature seen in Chapter 8.

This is why there is a permanent “XXX” seen in the first three digits of <“Status out [1-16]”>.

Digital Outputs 4 to 16 are not pre-allocated to a Flow Computer feature. They are mainly used by the support for Turbine Flowmeter Proving. (See Chapter 16).

d

b

c

Status outputsXXX000010000000

a

This Status Outputis presently active

(positive logic)

Status Output #16


7955 2540 (CH011/AF) Page 11.85

11.37 LIVE PULSE OUTPUTS

Feature: • Pulse Outputs supported by 7955

Pulse output channels 1 to 5 What to do:

Use this page to configure basic information for the pulse output channels. A channel can be set-up to transmit each increment to a normal mode total as a pulse train, suitable for an external counter. The individual pulse has a significance that equates to a certain mass or volume in the units of measurement already selected for the rate. As an example, consider a flow total increasing at a steady rate of one gallon every second and a pulse significance that is programmed with a value of six, representing six gallons. This would result in a single pulse being transmitted every 6 seconds.

Menu Navigation List: (1) <“Configure”>/<“Outputs”>/<”Pulse outputs”> Menu Data List:

Pulse Output Channel


Pulse Output Channel


Pulse o/p 1 source Pulse o/p 4 source Pulse Output 1 Pulse o/p 1 signif

Pulse Output 4 ** Pulse o/p 4 signif

Pulse o/p 2 source Pulse o/p 5 source Pulse Output 2 Pulse o/p 2 signif

Pulse Output 5 ** Pulse o/p 5 signif

Pulse o/p 3 source Pulse Output 3 Pulse o/p 3 signif

General Notes: A By default, parameters are not pre-allocated to pulse outputs B If the pulse frequency exceeds 10Hz (10 complete pulses per second), a ‘reservoir’ is used to keep a count of

the excess. Always SET a large enough pulse significance to avoid this occurring; if there is an excess, increase the significance value and wait for things to calm down again. Alternatively, all reservoirs can be cleared immediately by selecting the “Clear” command through the <“Clear pulse outputs”> parameter.

C Pulses are transmitted at evenly calculated intervals within the ‘window’ of a machine cycle. As the actual

machine cycle time always varies, the calculated interval between pulses will vary even when the value from the Pulse Output Source (e.g. a flow rate) has not changed – see Figure 11.37-1.

1.05 Seconds(Actual Cycle Time)

1.2 Seconds(Actual Cycle Time)

0.525s 0.6s

Figure 11.37-1: Example of pulse output distribution (for two machine cycles)


Page 11.86 7955 2540 (CH011/AF)

11.38 PASSWORDS AND SECURITY

The following pages explain how the 7955 can set-up to restrict access to facilities. Securable and non-secure modes

The 7955 can work in either a non-secure or securable mode. In the non-secure mode, anyone can have access to any of the facilities. In securable mode, access to facilities can be protected by passwords.

Changing security mode:

In the 7955 instruments, you can change the security mode by using the key-switch on the front of the instrument. The instruments are normally securable but, when you insert the key and turn it clockwise, this changes the mode to be non-secure. You can only withdraw the key in the vertical (securable) position.

Figure 11.38-1: The security lock on the 7955 instrument

LED

LOCK

Passwords and Security Levels A password system restricts access to its facilities to those people with certain levels of authority. There are four levels of Flow Computer security:

• Calibration (also referred to as the “Programmer” security level) • Engineer • Operator • World (anyone other than those listed above).

The table below lists what facilities each of these groups can access.

Access levels, and what they can have access to Facilities available

Calibration Engineer Operator World

Programmable parameters except security codes

YES

YES

All data or functions which don’t affect results

of calculations

NO

Security codes YES NO NO NO

Programming facilities YES YES NO NO

Calibration facilities YES NO NO NO

How the security LED appears

RED flashing RED ORANGE GREEN

Setting or changing a password (security level code)

1. Firstly, use the routine <“Enter Password”> menu data page for entering the password to change to the required “Calibration” (Programmer) security level.

2. From this menu, make a selection appropriate for the password (Programmer, Engineer, Operator or World) you want to define or change, then type in a password of up to 20 characters.

You can clear an existing password by pressing the CLR key. You can also have the same password for more than one security level. This would give you access to the facilities of all the levels covered by that password.


7955 2540 (CH011/AF) Page 11.87

PASSWORDS AND SECURITY

Feature: Keyboard Security Fallback (Optional) The present security level for information access through the keyboard can be automatically changed to “World” access after a user-defined period has elapsed without use of the keyboard. Use of the keyboard during that period causes the ‘lockout’ timer to be re-started. Security level changes can still be made at any time in the normal way (as explained earlier) but they will re-start the timer. By default, this security feature is not active. To activate, the length of time for the period must be ‘set’ to a value more than zero. Passwords to change security level are as already defined. • Configuration task: Enable keyboard security fallback


1. Navigate to this menu: <“Configure”>/<“Other parameters”>/<“Security”>/<“User interface”>

2. Locate the “Security timeout” menu data page and then ‘SET’ a value for the time-out period. It is not advisable to programme a time of less than 15 seconds.

(End of configuration task) To de-activate this feature, ‘SET’ the value of the “Security timeout” parameter to zero.

Feature: Communications Security Fallback (Optional)

Virtual slave access through the serial port can be blocked after a period has elapsed without use. Writing a communications password to database location 3187 is then the only way to un-block the serial port. Using the serial communication link during the period causes the ‘lockout’ timer to be re-started.

By default, this feature is not active. To activate it, the length of time must be ‘SET’ to a value more than zero. A communications password should be also ‘SET’ rather than keep the default one.

• Configuration task: Enable communications security fallback


1. Change security level to “Calibration” (i.e. flashing red security LED)

2. Navigate to this menu: <“Configure”>/<“Other parameters”>/<“Security”>/<“Communications”>

3. Locate the <“Comms secure timeout”> menu data page and then ‘set’ a value for the time-out

4. (Optional) Locate the <“Comms password”> menu data page and then ‘SET’ a new password. (End of configuration task) To de-activate this feature, ‘SET’ the value of the <“Comms secure timeout”> parameter to zero.


Page 11.88 7955 2540 (CH011/AF)

11.39 MULTI-PAGE MULTI-VIEW What is Multi-view?

Multi-view (often referred to as the “User Display”) is a display, which you define to show whatever information you want. It consists of one or more pages with the four lines on each page comprising of either or both of:

• Text (such as the name of a parameter), at the left of the line. • A value for a parameter, at the right of the line.

You can change the configuration of a Multi-view display whenever you wish. An example of a typical multi-view display is shown below. How to get into Multi-view To see the first Multi-view display page, press the MULTI-VIEW soft-key (i.e. the TOP blank key). A multi-view display page looks like the example below.

Figure 11.39-1: A typical multi-view display page

a

b

c

d

V

Text width settinga movable boundary

between text and value

Text (parameter name,in this case)

Value ofparameter

RPM 200.0

Visc 10E04

Dens 850.0

Temp A 20.00

Use the DOWN-ARROW key to page down through other multi-view displays. The message “Invalid MultiView Page” appears to indicate that no further pages are defined. Use the UP-ARROW to reverse through the display pages. Configuring Multi-view Follow this procedure for configuring Multi-view:

Step 1: Decide what text you want to display

You almost certainly want each line of the Multi-view display to show the name (possibly in an abbreviated form) of a parameter whose value you want to display. Bear in mind that: • Text cannot exceed 11 characters.

• The display leaves a space between the text and value.

• The value is displayed as a number without any units. You may wish to include the units as part of the text.

Step 2: Find the database location IDs of the parameters

1. In the menu system, find the parameter you want

2. Press the ‘a’ soft-key to display the location identification number (ID:xxxx)

3. Note down that ID number

4. Repeat this for the other parameters.

Step 3: Open the Multi-view configuration menu

1. Navigate to this menu: <”Configure”>/<”Multi-view”>


7955 2540 (CH011/AF) Page 11.89

CONFIGURATION MULTI-PAGE MULTI-VIEW

Step 4: Entering the text and location ID for each line

1. Select whichever MULTI-VIEW page (1 - 15) you want to configure

2. Select whichever line (1 - 4) you want to configure

3. Enter the line text you require

4. Enter the parameter (database location ID) you require.

Note that after the location ID is entered, the display changes to show the name of the parameter.

Step 5: Set the text width

The text width is the number of characters you want the text to occupy. If you want to set the text width:

1. Go to the <Text width> menu data page.

2. Edit the text width value


Page 11.90 7955 2540 (CH011/AF)

Chapter 12 Routine operation (Data maps)

7955 2540 (CH12/AD) Page 12.1

12. Routine operation (Data Maps)

12.1 Viewing the data The diagrams on the following pages show that part of the menu structure which you use to carry out routine tasks such as checking results or changing units of measurement.

12.1.1 Data Map: Flow rates and totals…………………………….….……… 12.2

12.1.2 Data Map: Density, Base density and Specific Gravity………..……. 12.4

12.1.3 Data Map: Viscosity…………………………………………….……….. 12.5

12.1.4 Data Map: Temperature and pressure………………..………………. 12.6

12.1.5 Data Map: Smaller topics………………………………..…...…………. 12.8


Page 12.2 7955 2540 (CH12/AD)

12.1.1 Data Map: Flow rates and totals

Flow rates have the following menu structure for routine work:

Main Menu Level #2 Level #3 Level #4

Flow rates → MeterRun flowrates → Ind vol rate → Ind vol rate

Gross vol rate → Gross vol rate Inc std vol rate → Inc std vol rate Gross std vol rate → Gross std vol rate Mass rate → Mass rate Net oil/water rate → Oil vol rate → Oil std vol rate → Oil mass rate → Water vol rate → Water std vol rate → Water mass rate → Volume cor factor → Volume cor factor Combine cor factor → Combined cor factor Ind mass rate → Indicated Mass rate

Station flowrates → Ind vol rate → Stn ind vol rate Gross vol rate → Stn gross vol rate Ind std vol rate → Stn ind std vol rate Gross std vol rate → Stn gro std vol rate Mass rate → Stn mass rate Net oil/water rate → Oil vol rate → Oil std vol rate → Oil mass rate → Water vol rate → Water std vol rate → Water mass rate → MeterRun flow lmts → Gross vol → Gross vol HI limit → Gross vol LO limit → Ind std vol → Ind std HI limit → Ind std LO limit → Gross std vol → Gross std HI limit → Gross std LO limit → Mass → Mass HI limit → Mass LO limit → Net oil limits → Oil volume → Oil std volume → Oil mass →


7955 2540 (CH12/AD) Page 12.3

Flow totals have the following menu structure for routine work:


Flow totals → Meter run totals → Ind volume total → Ind volume total

Gross volume total → Gross vol total Inc std vol total → Inc std vol total Gros std vol total → Gross std vol total Mass total → Mass total Net oil & water → Oil vol total → Oil std vol total → Oil mass total → Water vol total → Water std vol totl → Water mass total → Alarm total → Alarm total

Station totals → Ind volume total → Stn ind vol total

Gross volume total → Stn gross vol total Ind std vol total → Stn ind std vol totl Gros std vol total → Stn gro std vol tot Mass total → Stn mass total Net oil & water → Oil vol total → Oil std vol total → Oil mass total → Water vol total → Water std vol totl → Water mass total → Product totals → Totals → Product 1 → : : Product 20 → Product ID → Current product ID Product name → Product name


Page 12.4 7955 2540 (CH12/AD)

12.1.2 Data Map: Density, Base density and Specific Gravity

Density, Base density and Specific Gravity have the following menu structure for routine work:


Density → Header density → Header density → Header density Select header dens → Select header dens Density A → Density A Density B → Density B Header dens limits → Dens HI limit → Dens LO limit → Dens comparison → Base density → Base density → Base density

Base dens API → API temp corr CTL → API press corr CPL → Compress factor → Alpha coeff → Base dens limits → Base dens HI limit → Base dens LO limit → Meter run density → Meter run dens → Meter run density

Meter run dens API → API press corr CTL → API press corr CPL → Alpha coeff → Compress factor → Specific gravity → Specific gravity → Specific gravity

Water density → Water density (SG) SG limits → SG HI limit SG LO limit

Degrees API → Degrees API

MeterRun txdr dens → MeterRun txdr dens → Density Txdr value

Limits → HI limits → LO limits → Header visc dens → Header visc dens → Visc prime density

Selected visc dens → Select header visc Visc A dens → Density C value Visc B dens → Density D value

Net oil/water dens → Base oil density → Base density oil

Base water density → Base density water Head oil density → Header density oil Head water density → Header density water Meter oil dens → Line density oil Meter water dens → Line density water Oil SG → Oil specific gravity Oil degrees API → Oil degrees API


7955 2540 (CH12/AD) Page 12.5

12.1.3 Data Map: Viscosity

Viscosity measurements have the following menu structure for routine work:


Viscosity → Header visc → Header dyn visc → Header dyn visc

Header kin visc → Header kin visc Select header visc → Select header visc Dyn visc A → Dynamic visc A Dyn visc B → Dynamic visc B Kin visc A → Kinematic visc A Kin visc B → Kinematic visc B Header visc limits → Header dyn limits → Header kin limits → Meter txdr visc → Meter txdr dyn vis → Meter txdr dyn vis → Limits → Meter txdr kin vis → Kin visc Txdr value

Meter run dyn visc → Meter dynamic visc

Meter run kin visc → Meter kinematic visc

Base kin visc → Base kinematic visc


Page 12.6 7955 2540 (CH12/AD)

12.1.4 Data Map: Temperature and pressure

Temperature measurements have the following menu structure for routine work:


Temperature → Meter run temp → MeterRun tempera..

Dens temperature → Header dens temp → Header dens temp

Density A temp → Density A temp Density B temp → Density B temp

Visc temperature → Header visc temp → Header visc temp

Visc A temp → Visc A temperature Visc B temp → Visc B temperature

Prover temperature → Prover inlet temp → Prover inlet temp

Prover outlet temp → Prover outlet temp

Base temperature → Base temperature

Absolute zero → Absolute zero

Temperature limits → Meter run temp → High limit → Low limit → Density A temp → High limit → Low limit → Step limit → Density B temp → High limit → Low limit → Step limit → Prover inlet temp → High limit → Low limit → Prover outlet temp → High limit → Low limit → Viscosity A temp → High limit → Low limit → Step limit → Viscosity B temp → High limit → Low limit → Step limit →


7955 2540 (CH12/AD) Page 12.7

Pressure measurements have the following menu structure for routine work:


Pressure → Meter run pressure → Meter run pressure

Header dens press → Header dens press

Prover pressure → Prover inlet press → Prover inlet press

Prover out press → Prover outlet press Prv plenum pressure → Prv plenum pressure

Base pressure → Base press value

Equilib pressure → Equilibrium press

Atmos pressure → Atmos pressure

Pressure limits → Meter run pressure → High limit → Low limit → Header dens press → Dens press HI lmt → Dens press LO lmt → Dens pres step lmt → Prover inlet press → High limit → Low limit →

Press out press → High limit → Low limit →


Page 12.8 7955 2540 (CH12/AD)

12.1.5 Data Map: Smaller topics

Smaller topics have the following menu structure for routine work:


Special equations → Special eq 1 value

Sediment & water → Header BSW → Head BSW% → Head BSW%

Head volume oil% → Head volume oil% Prime BSW analyser → Prime BSW value →

BSW prime selected →

BSW A value →

BSW B value →

Limits → High limit →

Low limit →

Base BSW → Mass water% → Mass water%

Mass oil% → Mass oil% Std vol water% → Std volume water% Std vol oil% → Std volume oil% Water mass% limits → High limit →

Low limit →

Water std vol % lmt → High limit →

Low limit →

Meter run BSW → Meter run BSW% → Line BSW%

Meter run vol oil% → Line volume oil% Limits → High limit →

Low limit →

Meter run CSW% → Meter CSW Password → Enter password

Time → Time and date → Time and date

Set cycle time → Target cycle time

Actual cycle time → Actual cycle time

System idle time → Idle cycle time


7955 2540 (CH12/AD) Page 12.9

12.2 Checking the performance of the 7955 If you want to check that the external connections are working properly, the <Health Check> facility can help you. It shows, for each external connection:

• the name of the input or output • the value of the data • the units for the data • whether the data is live or set

If the data is live but the value appears to be unusually high or low, this may be because the external connection is not working properly.

12.2.1 Data Map: Health check

The <Health Check> feature has the following menu structure: (Part 1 of 2)


Health check → Inputs → Analog inputs → mA/RTD input 1 →

: mA/RTD input 16 Time period inputs → Time Period I/P 1 →

: Time Period I/P 4 →

7827 Period I/P 1b →




Flow meter inputs → Turb/Coriolis →

Orifice/DP →

Status inputs → Status in [1-16] →

Status in [17-26] →

Pulse inputs → Pulse input 1 →

: Pulse input 5 →

HART inputs → HART board status →

HART 1 value →

: HART 16 value →

Strainer input → Status →

DP value →

Outputs → mA outputs → mA output 1 →

: mA output 8 →

Status outputs → Status out [1-16] →

Status out [17-25] →


Page 12.10 7955 2540 (CH12/AD)

The <Health Check> feature has the following menu structure: (Part 2 of 2)


Health check → Flowmeter details → Turb/Coriolis/PD → Meter frequency →

Meter factor →

K factor →

Pulse error count →

Orifice/DP → Beta →

Discharge coeff →

Expand factor →

Vel of approach →

Reynolds number →

Corr pipe diameter →

Corr orif diameter →

Press loss value →

Mass rate K factor →

Pressure ratio →

Totals → Standard increment → Ind vol total →

Gross vol total →

Ind std vol total →

Gros std vol total →

Mass total →

Net oil & water →

Alarm total →

Maintenance → Totals →

Increments →

Viscometer Viscometer 1 Visc 1 Q factor →

Visc 1 Range →

Viscometer 2 Visc 2 Q factor →

Visc 2 Range →


Visc 3 Range →


Visc 4 Range →

User alarms → Alarms: ABCDWXYZ

Enet card status → SW version → Enet card sw version

MAC address → MAC address


7955 2540 (CH12/AD) Page 12.11

12.3 Printed reports This section explains how a 7955 Flow Computer can print a variety of sytem reports.

12.3.1 Types of report

There are a variety of printed reports to choose from.

Report name (as displayed) Content of report

Current report This shows settings and values of up to 20 data locations that have been set-up in a user-defined list. (Refer to Chapter 9 for a guide to this report)

Alarm report Contents of the Historical Alarm Log and attributes of up to 20 user-nominated parameters.

Event report Contents of the Historical Event Log and attributes of up to 10 user-nominated parameters.

Config report Application configuration details and attributes of up to 10 user-nominated parameters.

Current batch Current batch transaction record and attributes of up to 10 user-nominated parameters. (See “Batching” in Chapter 18)

Previous batch Previous batch transaction record and attributes of up to 10 user-nominated parameters. (See “Batching” in Chapter 18)

Prove report General Proving Session Report. (See Chapter 16A for the report format)

Brooks prove rpts Brooks Compact Proving Session Report

MM prove reports Master Meter Proving Session Report. (See Chapter 16B for the report format)

Product report Product totals report

Alarm log The “Alarm” trigger Archive. (See Chapter 9 for details of Archiving)

Manual log The “Manual” trigger Archive. (See Chapter 9 for details of Archiving)

Daily log The “Daily” trigger Archive. (See Chapter 9 for details of Archiving)

Interval log The “Interval” trigger Archive. (See Chapter 9 for details of Archiving)

Reports can be enhanced to include header and footer information. (See PRINT MENUs: <”Header & footer”> and <”Define reports”>)

12.3.2 Printing a report Reports have to be printed out individually. Each print request involves selecting a report name (description) from a fixed list of all reports. The contents of that report is then transmitted through a serial communications port that has been set-up for connection to an ASCII compatible output device. The “World” security level prevents everyone from requesting a report to be printed. However, all other security levels can be used to request any of the reports that are listed above. To find out about how to change security level, refer to the “Password and Security” section in Chapter 11. How to print a report using the front panel keyboard Follow these instructions:

1. Ensure that at least one serial communications port is configured for printing and the port is suitably connected to either an ASCII printer or a PC running a terminal emulation program. (Note: The set-up on the output device outside the scope of this Operating Manual)

2. Press the PRINT MENU key

3. Navigate to this menu: <“Print report”>

4. Edit the option (value) to be one of the report descriptions from the fixed list

5. Watch the report appear either on the ASCII output device.


Page 12.12 7955 2540 (CH12/AD)

How to print a report by other methods Method #1: ‘Remote’ Print via MODBUS A MODBUS networked device can directly manipulate database locations of the 7955 Flow Computer. With this method, a MODBUS ‘write’ command message can be used to write a report identification code to the parameter <”Print”>. The identified report is then be transmitted as normal.

Chapter 7 features worked examples of supported MODBUS commands that can be very easily adapted for this purpose. It will be necessary to know the location number of “Print Report” for part of the command sequence. This can be done by pressing the PRINT MENU key, searching the menu structure and then, once found, pressing the ‘a’ soft-key.


1. Ensure that a serial communications port is configured for printing and the port is suitably connected to either an ASCII printer or a PC running a terminal emulation program. (Note: The set-up on the output device outside the scope of this Operating Manual)

2. Transmit a MODBUS write command to the 7955 Flow Computer machine.

Report Identification Codes are as shown Table 12.3.1.

3. Watch the report appear either on the ASCII output device.

Table 12.3.1: Report Selection Codes

Value Report Selected

0 "None" 1 "Current report" 2 "Alarm report" 3 "Event report" 4 "Config report" 5 "Current QTR" 6 "Previous QTR" 7 "Prover report" 8 “Brooks prove rpts” 9 "Alarm log"

10 "Manual log" 11 "Daily log" 12 "Interval log"


7955 2540 (CH12/AD) Page 12.13

(How to print a report by other methods continued…)

Method #2: ‘Remote’ Print via Digital (Status) Input By default, Status Input 4 can be used by an external system to request a printout of the “Current” report. Follow these instructions:

1. Ensure that a serial communications port is configured for printing and the port is suitably connected to either an ASCII printer or a PC running a terminal emulation program (Note: The set-up on the output device outside the scope of this Operating Manual)

2. Ensure that the Status Input 4 is suitably wired to the external system that will activate it

It is possible to modify attributes of a digital (status) input: (a) Logic sense: Choose between “Positive Logic” (default) or “Negative Logic” (b) Mode: Choose between “Non latched” (default) or “Latched” Configuration parameters are under: <“Configure”>/<”Inputs”>/<“Status Inputs”> (or similar)

3. Test by activating the digital (status) input. It is possible to allocate this remote print function to another digital (status) input but care is needed to avoid clashes with the prover requirements (See Chapter 16) and the digital input allocated to selecting maintenance-mode. (Menu: <“Configure”>/<IO physical alloc”>)

12.3.3 Some typical reports (a) “Current” report with two user-nominated parameters

CURRENT REPORT ================ Report printing time: 21/02/2008 15:26:29 Tag number HB5X2540 Software Version 2540 Iss 2.00 Indicated vol rate 200.000 m3/hour SET Ind volume total 4039565.849 m3 ******************** END OF REPORT ********************

(b) “Alarm” report with one alarm

ALARM LOGGER REPORT ====================== Report printing time: 21/02/2008 15:28:00 Tag number HB5X2540 Software Version 2540 Iss 2.00 21/02/2008 13:30:31 OFF * Power fail SYSTEM 20/02/2008 17:17:39 ON * Power fail SYSTEM ******************** END OF REPORT ********************


Page 12.14 7955 2540 (CH12/AD)

(c) “Event” report with two events

EVENT LOG REPORT ================ Report printing time: 21/02/2008 15:43:44 Event List: ---------- 14/02/2008 16:46:25 USER, Input channel 1 * New: 0.000 % SET Old: 25.000 % SET 14/02/2008 16:45:30 USER, BSW pcent @ 100% * New: 100.000 % Old: 0.000 % ---------- Tag number HB5X2550 Software Version 2540 Iss 2.00 Power fail time 20/02/2008 17:17:39 ******************** END OF REPORT ********************

12.4 Giving your 7955 instrument a tag number If you have more than one 7955 Flow Computer you may want to give each instrument a tag number so that, in printed reports for example, you know which one the report refers to. To allocate an identifier…

1. Select the <”Unit tag number”> option on the Main Menu.

2. Press the ‘b’ soft-key. (The cursor shifts to the left of the screen)

3. Key in the identifier you want. (This over-types any existing identifier)

4. Press the ‘b’ soft-key again. (The new details shift back to the right of the display).

12.5 Giving metering-points a tag number You may want to give each metering-point a tag number so that, in printed reports for example, you know which one the report refers to. To allocate an identifier…

1. Select the <”Stream tag number”> option on the Main Menu.

2. Press the ‘b’ soft-key. (The cursor shifts to the left of the screen)

3. Key in the identifier you want. (This over-types any existing identifier)

4. Press the ‘b’ soft-key again. (The new details shift back to the right of the display).

Chapter 13 Routine maintenance and fault-finding

7955 (Ch13/BD) Page 13.1

13. Routine maintenance and fault finding

13.1 Cleaning the instrument You can use a cloth or sponge and water clean the outside of the instrument. Do not use caustic cleaning agents or abrasive materials.

13.2 Fault finding Although the instrument is designed to be extremely reliable it is possible that faults may arise at some time or another. The fault-finding charts show the most likely faults and explain how to trace their causes and put them right. If you cannot cure a fault yourself, contact your supplier or the manufacturers for help.

Note: • Use the “Health Check” facility on the 7955 to monitor a variety of measurement parameters,

including time period inputs, analogue inputs and status inputs and outputs. This can be used as a diagnostic aid if the system seems to be faulty.


Page 13.2 7955 (Ch13/BD)

Is thetransmitter

receiving powerfrom the

795x?

Isthe 795x

configuredcorrectly

?

Is thetransmitter

sending currentto the 795x

?

Has itever beendisplayed

?

YES

YES

YES

YES

795x's Connector/Power Supply Boardis probably faulty

Correct theconfiguration

The 795x's inputcircuit is probablyfaulty

The transmitter orits configurationis probably faulty

NO

NO

NO

NOIs the

transmitter'sfield wiring

correct?

Check the field wiringagainst the wiringschedule

The field wiringis faulty

Wire the transmitterup according to thewiring schedule

Replace the fieldwiring to thetransmitter

Change theConnector Board

Refer to thetransmitter's manualfor more information.

Replace the 795x'sConnector/PowerSupply Board

A reading froma transmitter isnot displayed

NO

YES

PROBLEM:

Figure 11.3: Fault-finding chart 1: No reading from a transmitter

Take great care during this procedure because thepower supply must be ON when you carry it out.


7955 (Ch13/BD) Page 13.3

Hasthe fuse

in the 795xblown

?

Is thesecurity LEDon the 795x

lit?

Is thepower tothe 795x

ON?

YES

YES

795x's Connector/Power Supply Boardis probably faulty

NO

NO

NO

Is the795x's supplyvoltage within

spec?

Turn the power ON

Replace the 795x'sConnector/PowerSupply Board

YESThe 795x's DisplayModule is probablyfaulty

Replace the 795x'sDisplay Module

The display is blank

Adjust the voltage sothat it is within spec

NO

PROBLEM:

Replace the fuse byone of the correctrating

YES

Figure 12.2: Fault-finding chart 2: The display is blank


Page 13.4 7955 (Ch13/BD)

Chapter 14 Removal and replacement of parts

7955 (Ch14/AC) Page 14.1

14. Removal and replacement of parts

14.1 Front Panel Assembly

Switch paneland bezel

Display

Front PanelAssembly

Displaycable

PL1 PL2

Display fixing screwsand washers (4 off)

Bezel fixingscrews (4 off)

ProcessorBoard

Case

Figure 14.1: Removing the Front Panel Assembly

1. Undo and remove the four screws which secure the Bezel to the case. Withdraw the Front Panel Assembly to the limits of the connecting wiring then lay it on top of the case.

2. Partially withdraw the Processor Board then disconnect the two connectors from the Processor Board. The Front Panel Assembly is now free.

3. Replace all items by reversing this procedure. Take great care to ensure that the cables are not pinched on re-assembly.

14.2 Display 1. Remove the Front Panel Assembly as explained in Section 14.1.

2. Undo and remove the four screws and washers which attach the display to the Front Panel Assembly.

3. If required, unplug the ribbon cable from the display.

4. Replace all items by reversing this procedure.


Page 14.2 7955 (Ch14/AC)

14.3 Switch Panel

Bezel

Displayand cable

Display fixing screwsand washers (4 off)

SwitchPanel

Switch Panelfixing nuts andwashers (4 off)

Springclip

Keyswitch

Switchcable

Figure 14.2: Removing the Switch Panel Assembly

1. Remove the Front Panel Assembly as explained in Section 14.1

2. Undo the four screws and washers which attach the display to the bezel. Remove the display.

3. Un-solder the flexi-cable from the key switch. Remove the spring clip from the switch then withdraw the switch from the case.

4. Undo and remove the four nuts and washers which attach the Switch Panel to the bezel. Lift the Switch Panel away.

5. Replace all items by reversing this procedure.


7955 (Ch14/AC) Page 14.3

14.4 Processor Board

Switch Paneland Bezel

Displaycable

PL1 PL2

Switch panelcable

Power SupplyBoard

ProcessorBoard

MotherBoard

Figure 14.3: Removing the Processor Board and Power Supply Board


2. Pull the Processor Board forwards so that it disengages from the connector at the back of the case. Withdraw the board from the case.


14.5 Power supply board 1. Undo and remove the four screws which secure the Bezel to the case. Withdraw the Front Panel

Assembly to the limits of the connecting wiring then lay it on top of the case.

2. Pull the Power Supply Board forwards so that it disengages from the connector at the back of the case. Withdraw the board from the case.


14.6 Connector Board 1. Remove the Rear Panel Assembly as described in Section 14.9.

2. Remove the Mother Board as explained in Section 14.10.

3. Unscrew the threaded hexagonal spacers on top of the Connector Board, then lift the Connector Board off the studs.



Page 14.4 7955 (Ch14/AC)

14.7 Fuse 1. Undo and remove the four screws which secure the Bezel to the case. Withdraw the Front Panel

Assembly to the limits of the connecting wiring then lay it on top of the case.

2. Slide the Power Supply Board out of the case.

3. Referring to the diagram, find the fuse and gently prise it out of the fuse holder.

4. Press the replacement fuse into the fuse holder. Make sure that the fuse is of the correct type and rating as specified in Chapter 14.

5. Replace all items in the reverse order of removal. Take great care to ensure that the cables are not pinched on re-assembly.

PowerSupplyBoard

MotherBoard

RearPanel

Top ofinstrumentcase

SocketSK1Fuse

Figure 14.4: Where to find the fuse on the Power Supply Board


7955 (Ch14/AC) Page 14.5

14.8 Back-up battery Instructions:-

1. Ensure that the unit is disconnected from all power supplies.

2. Ensure that a new battery and a thin edged, non-conductive implement are within easy reach.

3. Remove the Front Panel Assembly from the unit as explained in Section 14.1.

4. Remove the Processor Board from the unit as explained in Section 14.4.

5. Referring to the diagram below, use the non-conductive implement to gently lever the battery upwards from near the rear of the clip. As soon as the battery lifts up a small amount, gently ease the battery in a horizontal direction away from the holder and the clip. Keep the battery in contact with the clip.

DO NOT LIFT UP THE CLIP MORE THAN ABSOLUTELY NECESSARY.

6. Keep the battery in contact with the clip until you are prepared to insert the new one. When the clip looses contact with the battery, there is a maximum of 10 seconds before all configuration and database information is lost.

7. Once prepared, remove existing battery and then slide the new one under the clip and into the holder - observing the polarity symbols. Complete this action within 10 seconds.

8. Re-assemble the 7955 instrument

Part ofProcessorBoard

Batteryholder

Battery

Clip/contact

Figure 14.5: Where to find the back-up battery on the Processor Board


Page 14.6 7955 (Ch14/AC)

14.9 Rear Panel Assembly It is strongly recommended that in order to ensure continued compliance to EMC directives, you do not attempt to remove the rear panel assembly, but return the instrument to your nearest Service Centre.

The instructions given below should only be carried out if it is absolutely necessary.

ProcessorBoard

Rear PanelAssemblyfixing screws(4 off)

Power SupplyBoard

MotherBoard

Figure 14.6: Removing the Rear Panel Assembly


2. Pull the Processor Board forwards so that it disengages from the connector at the back of the case. Withdraw the board from the case.

3. Pull the Power Supply Board forwards so that it disengages from the connector at the back of the case. Withdraw the board from the case.

4. Remove the four screws which secure the Rear Panel Assembly into the case.

5. Withdraw the Rear Panel Assembly from the case, taking care not to bend the metal spring clips on the top and bottom of the Connector Board.

6. Replace all items by reversing this procedure. Take great care to ensure that the cables are not pinched on re-assembly, and ensure that the metal clips are not bent or damaged.


7955 (Ch14/AC) Page 14.7

14.10 Mother Board It is strongly recommended that in order to ensure continued compliance to EMC directives, you do not attempt to remove the rear panel assembly, but return the instrument to your nearest Service Centre.

1. Remove the Rear Panel Assembly as described in Section 14.9.

2. Referring to the diagram, undo and remove the six screws and washers which fix the Mother board to the rest of the Rear Panel Assembly.

3. Using a straight pull, carefully lift the Mother Board clear of its four connections to the connector board. The Mother Board is now free.

4. Replace all items by reversing this procedure. Take great care to ensure that the cables are not pinched on re-assembly, and ensure that the metal clips are not bent or damaged.

COMPLETE ASSEMBLY DISMANTLED ASSEMBLY

MotherBoard

Threadedspacers

ConnectorBoard

RearPanel

Earth studand fixings

Screws andwashers

Rearpanel

Plainspacers

Figure 14.7: Removal of the Mother Board and Connector Board


Page 14.8 7955 (Ch14/AC)

14.11 Guide to fitting the Ethernet board (Warning! You must take precautions to prevent a static charge from damaging PCBs. An earth wrist-strap is ideal)


1. Ensure jumpers on the Ethernet board are configured correctly. Use Table 14.11.1 to verify this. (Figure 14.9 shows where to find these jumpers)

2. Remove the front panel assembly, as guided in Section 14.1 of Chapter 14

3. Remove the processor board, as guided in Section 14.2 of Chapter 14

4. Locate connectors PL12, PL13 and PL14 on the processor board. They are used for attaching the Ethernet board to the processor board. Remove any bridges you may see covering pins of PL12 – PL14. (Figure 14.11 indicates where to find the connectors).

5. If vibration is significant where the 7955 instrument is to be sited, you should plug in a plastic post, similar to Figure 14.8, into a hole on the processor board. The location of the hole is indicated in Figure 14.11

The plastic post is supplied with the Ethernet board. Fitting it is optional but will prevent the Ethernet board from shaking loose when the 7955 instrument is sited in an area with vibrations.

6. When ready, bring the Ethernet board to just above the processor board

7. Align the connector blocks underneath the Ethernet board with PL12, PL13 and PL14 on the processor board. (Figure 14.10 shows the connector blocks). If using the plastic post (from step 5), it should now be naturally aligned with the hole on the Ethernet Board. (The hole is shown in Figure 14.9)

8. Check visually for a good alignment and then apply a gentle pressure from above, but only over the connection points

9. Once the Ethernet board begins to engage onto the processor board, re-check the alignment at all the connecting points. If okay, apply further pressure until it is fully engaged. Otherwise, disengage carefully and return to step 6. If the plastic post (from step 5) has engaged, you may need to simultaneously squeeze the anchored tip and lift board up to disengage.

10. Re-insert the processor board

11. Re-attach the front panel

12. Power-up the 7955 instrument when it is fully re-assembled

13. Once the power-cycle is complete, you need to check that the Ethernet board is functioning. To do this, navigate to the <Health Check>/<”Enet card status”> menu and then review settings for the MAC address and Software version. The card is incorrectly installed if you see “Not available”.

Table 14.11.1: Jumper Configuration for Ethernet Board

JP1 JP2 JP3 JP4 JP5 JP6 JP7 JP8 JP9 JP10 JP11

Made Open Open Made Open Made 2-3 Made Open Open Open Open

Note: “Made” – Bridge covers pins 1 and 2 unless specified otherwise, “Open” – No bridge covers the pins

Figure 14.8: Optional Plastic Post


7955 (Ch14/AC) Page 14.9

Figure 14.9: Ethernet Board 79550509 (Top View)

Note: The PL5 and JP8-11 connectors on the top surface are for factory testing

Figure 14.10: Ethernet Board 79550509 (Bottom View)

Figure 14.11: Area of PL12, PL13 and PL14 on Processor Board


Page 14.10 7955 (Ch14/AC)

Chapter 15 Assembly drawing and parts list

7955 (CH15/AA) Page 15.1

15. Assembly drawing and parts list

15.1 What the drawing and parts list tell you The drawing and parts list show those parts of the 7955 which you can obtain as spares. To identify an item:

1. Find the item on the appropriate assembly drawing (Figure 15.1).

2. Note the Item Number by the side of it.

3. look up the Item Number on the parts list (Table 15.1)

The parts list tells you:

the Part Number for the item

a description of the item

the quantity of the item that appears on the drawing

15.2 How to obtain spare parts You can obtain spare parts from the supplier from whom you bought the instrument, or from the factory direct (see contact details on back page). In either case, you must state on your order:

your name, address and telephone or fax number

a description of the parts you want

the part numbers of the items you are ordering

the quantity of each item


Page 15.2 7955 (CH15./AA)

Figure 15.1: Diagram for identifying and ordering spares


7955 (CH15/AA) Page 15.3

Table 15.1: Parts List

Item no. Part number Description Quantity

1 79553700 Instrument case 1

2 79513703 Bezel 1

3 79511206 Display assembly 1

4 79550503 Motherboard assembly 1

5 79550504 Connector board assembly (D-type connectors) 1

6 79553701 Rear panel (D-type connectors) 1

7 79513705 Switch panel (with cable) 1

8 376100160 Keyswitch and retainer 1

9 79550502 Processor board 1

10 79510501 Power supply board 1

11 411129010 M3 crinkle washer 14

12 79513710 15-way cable 1

13 410031010 M3 hexagonal full nut 4

14 400001930 M4 thumb nut 1

15 410031020 M4 hexagonal full nut 1

16 411029020 M4 plain washer 2

17 412011420 Nylon spacer: 3.5mm ID x 8mm long 6

18 415370070 Hexagonal spacer: M3 x 13mm long 6

19 406803060 M3 x 6mm pan-head screw 10

20 411129020 M4 crinkle washer 2

21 406902460 M3 x 8mm pan-head screw 8

22 360106230 2A glass 1

23 800400380 Lithium battery CR2330 1


Page 15.4 7955 (CH15./AA)

Chapter 16 HART, SMART and the 7955

7955 (CH16/AB) Page 16.1

16. HART, SMART and the 7955

16.1 What this chapter tells you This chapter is a comprehensive guide for understanding how the 7955 Flow Computer can be set-up for digital communications with “SMART” † type field transmitters.

Important Notice This chapter is only relevant to 7955’s with the “HART” add-on board installed.

16.2 Introduction to SMART and HART with the 7955 A special add-on board‡ is required to be installed inside the 7955 before this facility is enabled. This board provides all the necessary hardware and firmware support for the 7955 to communicate as a Current Input Device (Primary Master) on two separate two-wire, 4-20mA loops of “SMART” transmitters (Slaves).

Warning!! Each network loop must have no more than five “SMART” field transmitters connected at

any one time. Exceeding this number will damage add-on boards.

The following “safe area only” diagram shows all the HART network loops with the maximum number of “SMART” field transmitters connected to each loop. In practice, far fewer transmitters are used.

Take note of the warnings - above and below. Section 16.3 has details of external wiring involving the 7955.

HART Channel 2

HART Channel 1

T1 T2 T3 T4 T5

T1 T2 T3 T4 T5

HART Channel 4

HART Channel 3

T1 T2 T3 T4 T5

d

b

c

HART 1 Value0.125

Live

a

T1 T2 T3 T4 T5

Warning!! Connecting up “SMART” transducers has to be done with great care. Powering-up more than

one point-to-point configured transmitter on a HART network loop can produce an electrical current (20mA per transmitter) that can damage the 7955.

The communications standard for each network loop is the HART§ Protocol**. A full technical discussion of this standard is outside the scope of this operating manual. There is a detailed discussion of the HART protocol in the Rosemount booklet entitled “HART Field Communications Protocol - A Technical Description”. However, particularly important aspects involving the 7955 are covered in later section as they are needed.

† A “SMART” transmitter is said to be intelligent because it contains a micro-processor that provides extra functionality. This may

take various forms, such as on-board calculations, handling multiple sensors, combining types of measurement. measurement integrity indicators, and so on. “SMART” is also used for the ability to re-use existing field wiring.

‡ Part number is 79557 § This is an acronym for “Highway Addressable Remote Transducer”. HART is a registered trademark of the HART

Communication foundation. ** Implementation conforms to revision 5.5 of the HART protocol specification.


7955 (CH16/AB) Page 16.2

Application software is able to request data from dynamic variables that are kept and maintained by a “SMART” transmitter. These dynamic variables can be thought of as being very much like 7955 type data locations. Four dynamic variables per “SMART” field transmitter can be requested. A total of sixteen dynamic variables can be input to the 7955. Configuration details concentrate on setting up the 7955 to obtain up to eight (the maximum) measurement values.

HART 6

HART 8

HART 9

HART 7

HART 10

HART 11

HART 12

HART 13

Address = 1

HARTTransmitter

Primary

Secondary

Third

Fourth

Variables

Address = 9

HARTTransmitter

Primary

Secondary

Third

Fourth

Variables

HART network loop 2

Address = 1

HARTTransmitter

Primary

Secondary

Third

Fourth

Variables

Address = 8

HARTTransmitter

Primary

Secondary

Third

Fourth

Variables

7955 HART Inputs

HART network loop 1

HART 4

HART 5

HART 2

HART 3

HART 14

HART 15

HART 1

HART 16

Figure 16.1: Example of 2 HART Network Loops


7955 (CH16/AB) Page 16.3

16.3 Connecting the 7955 to a HART network loop This section covers installation issues for analogue input wiring involving the 7955.

16.3.1 7955 electrical connections and impedance requirements HART connections use analogue inputs 13, 14, 15 and 16 for HART network loops 1, 2, 3 and 4 respectively. The HART add-on board provides the hardware support for these inputs to become “SMART” analogue inputs.

Analogue input Signal +

24V d.c. (Isolated supply)

7955


Analogue input Signal -

100 Ohms

"SMART"Field

Transmitter

+

-Active

impedance

Note:To ensure reliableoperation, it is goodpractice to groundthe 0V d.c. isolatedsupply at one point.

Figure 16.2: “SMART” Analogue input on the HART add-on board (Internally powered)

Every analogue input on the 7955 Flow Computer utilises a internal 100Ω current sense resistor. The circuitry for the “SMART” analogue inputs on the HART add-on board use a 100Ω current sense resistor in series with an active impedance. The total impedance is then sufficient for reliable operations at HART signal frequencies, while minimising the dc voltage drop across the 7955 Flow Computer terminals. This allows a sufficient voltage at the field transmitter even when powered through I.S. Barriers (or Isolators). Parameter notes: 1. At d.c., the voltage drop at the maximum current of 22mA is 3.4V 2. Minimum impedance in the HART extended frequency band (500 -10khz) is 330Ω 3. Maximum impedance in the HART extended frequency band (500 -10khz) is 480Ω

HART network loop 1 (Analogue input 13):

Pin function D-Type Pin no.

D-Type Pin Designation

+24V d.c. (isolated supply) SK3/34 +24V Analogue Analogue input signal + SK3/40 Analog i/p 13 + Analogue input signal - SK3/39 Analog i/p 13 - 0V d.c. (isolated supply) SK3/18 0V Analogue


Pin function D-type Pin no.

D-type Pin Designation

+24V d.c. (isolated supply) SK3/34 +24V Analogue Analogue input signal + SK3/6 Analog. i/p 14 + Analogue input signal - SK3/22 Analog. i/p 14 - 0V d.c. (isolated supply) SK3/18 0V Analogue


7955 (CH16/AB) Page 16.4









16.3.2 Frequency-shift keying The HART protocol uses the American “Bell 202” standard frequency-shift keying (F.S.K.) method to mask a digital signal on to analogue wiring.

Important Notice The “HART” add-on board provides 4 HART channels that utilise existing Analogue Inputs (13, 14, 15 and 16). This allows SMART and Non-SMART instruments to use an analogue input at the same time. However, the F.S.K. signal produces random errors on the analogue signal which affect the normal accuracy (See Appendix ‘C’). We strongly recommend that analogue inputs being used for HART loop inputs should only be used for HART communications.

16.3.3 Cable choice and the 65μs rule There is a standard “65μs” rule that determines the maximum length of cable that can be used for reliable operation of the HART network loop.

Step 1: Add up all the resistance in the network loop.

• 7955 current sense resistance is equivalent to 350Ω with the HART add-on board. • I.S. Barrier or Isolator • Cable

Step 2: Find out the total cable capacitance

Step 3: Multiply the total resistance * total cable capacitance.

The resulting value must be less than 65μs.

We can provide multi-pair cable that has a maximum capacitance of 115 pF/m. The following table shows the recommended maximum cable lengths for typical HART network loops with this cable.


7955 (CH16/AB) Page 16.5

Table 16.1: Maximum cable lengths No. of slaves

Loop resistance

Max. Cable length

1 No Barrier 1171m 1 150Ω 884m 1 300Ω 713m 2 No Barrier 1136m 2 150Ω 846m 2 300Ω 673m 3 No Barrier 1101m 3 150Ω 807m 3 300Ω 633m 4 No Barrier 1067m 4 150Ω 769m 4 300Ω 593m 5 No Barrier 1032m 5 150Ω 730m 5 300Ω 553m

Table notes: 1. Cable length calculations take into account the 350Ω resistance from a 7955 with the HART Board. 2. It is assumed that a 150Ω I.S. Barrier has a maximum end to end resistance of 185Ω. 3. It is assumed that a 300Ω I.S. Barrier has a maximum end to end resistance of 340Ω.

A discussion of cable choices can be found in the Rosemount booklet entitled “HART Field Communications Protocol - A Technical Description”.

Important Notice: Field transmitters in hazardous areas

Always follow wiring instructions provided by manufacturers of the field transmitters.


7955 (CH16/AB) Page 16.6

16.4 Configuring the 7955 to use a HART network loop

16.4.1 Configuring by using the software wizard This sub-section covers step-by-step instructions for using a software wizard to configure a 7955 that has the following set-up:

Example 1

A HART network loop with one “SMART” static pressure field transmitter is attached to analogue input 15. The objectives of this example are:

• to set a multi-drop address • to get static pressure from the fourth dynamic variable (on the transmitter) into the first HART data

location dedicated to holding input values • to allocate the first HART data location to the Line pressure calculation


Go to the wizard selection menu

1. Press the MENU key so that page 1 of the main menu appears. 2. Use the DOWN-ARROW key until the “Configure” main menu option is

displayed. 3. Press the blue key that is alongside the “Configure” option 4. Press the ‘a’ key twice.

Select the Hart inputs wizard

5. Press the ‘b’ key and then use the DOWN-ARROW key to scroll through a list of wizards.

6. Press the ‘b’ key when “Hart inputs” appears on the display.

Select HART Input 1 7. Press the ‘d’ key to answer “yes” to the prompt.

Choose the HART network loop

8. “HART 1 PhyLinkNo” is set to “HART link 1” by default. This example involves HART network loop 1 (i.e. HART link 1) so there is no need to change the setting. However, If anything other than “HART link 1” is shown:

• Press the ‘b’ key and then use the DOWN-ARROW key to scroll through the options.

• Press the ‘b’ key when “HART link 1” is displayed. 9. Press the ENTER key to continue to the next step.

Choose the address of the “Field transmitter”

10. Press the ‘b’ key 11. Use the DOWN-ARROW key to scroll through the options until

“HART address 5” is shown. 12. Press the ‘b’ key to confirm this selection 13. Press the ENTER key to continue to the next step.

Choose the fourth dynamic variable


“Fourth variable” is shown. 16. Press the ‘b’ key to confirm this selection 17. Press the ENTER key to continue to the next step.

Choose the type of dynamic variable


“Static press (G)” is shown. 20. Press the ‘b’ key to confirm this selection. 21. Press the ENTER key to continue to the next step.

Select the averaging mode 22. Press the ENTER key to keep existing setting and continue to next step.


7955 (CH16/AB) Page 16.7

Put the field transmitter on-line

23. Press the ‘b’ key 24. Use the DOWN-ARROW key to scroll through the options until “On line”

is shown. 25. Press the ‘b’ key to confirm this selection 26. Press the ENTER key to continue to the next step.

Monitor the response from issuing the on-line/off-line command

27. Watch the response message. It should cycle from “None” to “Configured” in less than a minute. Note: The response “SMART error” may appear if there is there is a problem with the HART loop.

28. Press the ENTER key to continue to the next step. Change status to get live values from the field transmitter

29. Press the ‘d’ key 30. Use the DOWN-ARROW key to scroll through the options until “Live”

is shown. 31. Press the ‘b’ key to confirm this selection. Live static pressure values

(gauge units) should now be displayed. 32. Press the ENTER key to continue to the next step.

Skip remaining questions 33. Press the ‘c’ key to answer “no” to the prompt. 34. Repeat step 3 until the “Hart inputs” wizard is completed.

Allocate the HART data input location`

35. Use the “Pressure” wizard to make data location HART value 5 the source for the Line pressure calculation. Note: During the “Pressure” wizard, “Line press source” should be set to “HART input 5”.

(End of Example)

To view results after exiting the wizard, look in the menu :<“Health check”>/<“Inputs”>


7955 (CH16/AB) Page 16.8

16.5 Post configuration - viewing HART data This sub-section provides a complete check-list of all the data locations associated with checking information returning from HART network loops.

Task 1: Checking the results

Step 1: Select this menu : <“Health check”>/<“Inputs”>

Step 2: Look at data shown in this check-list

Data name Instructions and Comments

HART input 1 value HART input 2 value HART input 3 value Values from sixteen dynamic variables HART input : value HART input 16 value HART software ver • HART board firmware identification. HART no. of phy links • This shows the number of HART network loops. Default

setting is “None” HART status • This shows a digit for each of the sixteen HART data location

inputs: Digit = ‘0’ - Input is not configured (not in use) Digit = ‘1’ - Input is configured (in use) Digit = ‘2’ - Input configuration failed due to an error

• Note: Default state is 0000000000000000

16.6 SMART units of measurement Support is provided for a sub-set of the SMART units of measurement

Temperature Density Pressure Mass rate

1. Deg.C. 1. g/cc 1. In WG 1. g/sec 2. Deg.F 2. g/m3 2. mm WG 2. g/Min 3. Kelvin 3. lb/gallon (UK) 3. Bar 3. h/Hour 4. lb/ft3 4. mBar 4. Kg/sec

5. Kg/litre 5. Pa 5. Kg/Min 6. g/litre 6. MPa 6. Kg/day 7. lb/in3 7. In HG 7. Tonnes/Min 8. Tonnes/Hour

9. Tonnes/Day 10. Lb/sec 11. Lb/Hour 12. Lb/Day

Note:

Data values received in un-supported measurement units are displayed without units of measurement - line 3 of the display is blank. However, calculations that use this data always assume the default units of measurement. For temperature data, this would be “Deg.C”. Refer to Chapter 9 for a full list of supported units of measurement.

Chapter 16(a) Flowmeter Proving

7955 (CH16A/BC) Page 16A.9

When the piston reaches the end of the Prover Loop, the run is completed. The piston is automatically retracted back to the ‘standby’ (start) position for when the Prover receives another ‘start prove’ signal from the ‘Proving’ 7955. The pulses accumulated, over one volume sweep, will be less than 10,000 and, therefore, not sufficient to calculate the meter factor with an accuracy of +/- 0.01% (as required by ISO7278 / BS6866 part 3). Therefore, a method known as “double-timing pulse interpolation” is used to overcome this. A prove session consists of a series of runs. A run consists of passes. A pass is one ‘piston flight’. The number of consecutive passes and runs is user-definable. Calculations at the end of a run determine a ‘meter factor’ (MF) for that run. The MF is checked against user-defined limits, to determine if it is a ‘good’ or ‘bad’ factor value. At the end of a successful prove session, the final (session) MF is determined from the average pressures, temperatures and pulse accumulation (interpolated pulses). The session MF is checked against user-defined limits, to determine if it is a ‘good’ or ‘bad’ factor value. If it is a ‘good’ factor value, it is offered to the operator for acceptance; a ‘bad’ session MF is immediately discarded. If the MF is accepted, it is used in subsequent flow calculations. Otherwise, the MF is discarded and the previous pre-session value is re-used in subsequent flow calculations.


Page 16A.10 7955 (CH16A/BC)

16A.3 Double-time Pulse Interpolation This method is used by the 7955 for determining an accurate pulse count for the ‘Meter factor’ calculation. All supported pipe provers must use this method.

Figure 16-1: Timing for double-time pulse interpolation (positive edge detection)

T1

T2

etc.

Pulse train from a flow meter

Start and stop pulse(from detector switches)

0 1 N

Ignored in favour ofprevious pulse

B E

Ignored in favour ofnext pulse

2 3

‘T1’ is the accurate measurement of the time‡ between the rising edge (or falling edge) of the start pulse (nominated as ‘B’) and the rising edge (or falling edge) of the stop pulse (nominated as ‘E’).

Rising (positive) edge detection is shown in the figure above. However, the polarity of the edge detection process is software selectable. ‘T2’ is the accurate measurement of the time taken between ‘N’ complete (or even partial) pulses that fall within the ‘T1’ time frame. Pulses that are fully outside the ‘T1’ time frame are not counted. After a prove-run is completed, the 7955 carries out calculations to correct the raw pulse count:

First, using the equation: f NT

u1

2

=

Where:

f1 = frequency of incoming pulses during time frame ‘T2’. {Menu Data: <”Flowmeter freq”>}

Nu = Uncorrected pulses count during time frame ‘T2’…... {Menu Data: <”Prv run pulse count”>}

T2 = Time reference, ‘T2’……………………………………. {Menu Data: <”Prv run TDVOL”>}

Now, using the equation: f NT

c2

1

= and re-arranging it so that N f Tc = 2 1*

Where:

Nc = Corrected pulse count (as used in section 16A.4)….. {Menu Data: <”Prv run corr pulse”>}

f2 = f1 (frequency of pulses from flowmeter)…………..... {Menu Data: <”Flowmeter freq”>}

T1 = Time reference, ‘T1’……………………………..……… {Menu Data: <”Prv run TDFMP”>}

‡ Sometimes referred to as the “flight time”.


7955 (CH16A/BC) Page 16A.11

16A.4 The Prover Calculations This section lists all the major proving calculations § that are performed after each prove-run. However, it is the results from the end-of-session calculations that are important. This is emphasised with equation terms having references to the corresponding menu data in the session part of a Prover Archive. Turn to page 16A.56 for full information on the “Prover Archive”.

16A.4.1 Volumetric Prover Proving of a Volumetric Meter (by Volume) Calculation PRV#1: New ‘Meter Factor’

The ‘Meter factor’ is a result of the liquid flowmeter proving process. This factor is used when calculating the Gross Volume flow rate at the flow metering point.

Using: MFNew = GSVISV

p

m

Where: MFNew = New calculated ‘Meter factor’……………….. {Menu Data: <”Prv new meter factor”>}

GSVP = Gross Standard Volume (Prover)………….. {See next page}

ISVm = Indicated Standard Volume (Meter)………... {See Calculation PRV#4 on next page}

Calculation Notes: 1. The new ‘Meter factor’ is always calculated at the end of a successful session. It is then shown in the

session part of the Prover Archive even if it is not offered for acceptance or offered but then rejected.

2. The ‘Proving’ 7955 (or the combined ‘Metering/Proving’ 7955) will be configured to either offer the new

‘Meter factor’ or offer the new ‘K factor for acceptance to replace an existing meter-run (stream) value.

3. The replaced ‘Meter factor’ value is stored in the session menu at the <”Prv old meter factor”> menu

data page Calculation PRV#2: New ‘K Factor’

The ‘K factor’ is a result of the liquid flowmeter proving process. This factor is used when calculating the Indicated Volume flow rate at the flow metering point.

Using: KFNew = KF

MFOld

New

Where: KFNew = New calculated ‘K factor’……….……………. {Menu Data: <”Prv new K factor”>}

KFOld = Previous calculated ‘K factor’…….…………. {Menu Data: <”Prv old K factor”>}

MFNew = New calculated ‘Meter factor’………..…….... {See Calculation PRV#1 above}

Calculation Notes: 1. The new ‘K factor’ is always calculated at the end of a successful session. It is then shown in the

session part of the Prover Archive even if it is not offered for acceptance or offered but rejected.


‘K factor’ or offer the new ‘Meter factor for acceptance to replace an existing metering-run (stream)

value.

§ Implemented in accordance with section 12.2.7.6 of Chapter 12 from the API Standard (August 1987).


Page 16A.12 7955 (CH16A/BC)

Calculation PRV#3: Corrected Prover Volume

The base (calibrated) volume must be corrected for temperature and pressure conditions in the Prover.

Using: GSVp = ( )Vc Ctlp Cplp* *

Where: GSVP = Corrected Prover Volume (m³)….……………………{Menu Data: <”Prover corr volume”>}

Ctlp = Correction factor for effect of temperature on fluid in the Prover……..…..…..……………

………………………………………………………….……….{Menu Data: <”Prover CTLp”>} Cplp = Correction factor for effect of pressure on fluid in the Prover…..…………..………….……

………………………………………………………….……….{Menu Data: <”Prover CPLp”>}

And: Vc = ( )Vb Cts Cpsp p* *

Where: Vc = Corrected calibrated volume (m³)……………………………………..…………{Not in menu}

Vb = Base Volume of Prover (m³)…………………..……….…..{Menu Data: <“Prover volume”>}

Ctsp = Temperature correction factor for steel…….…………………….{See Calculation PRV#5}

Cpsp = Pressure correction factor for steel………….……………………{See Calculation PRV#6}

Calculation Note: 1. The values of Ctlp and Cplp are generated using the same method for generating Ctl and Cpl on the

‘Metering’ 7955 (or the combined ‘Metering/Proving’ 7955). Ctl and Cpl are both generated by the API

referral of the Base Density value to metering conditions. The ‘Metering’ 7955 must perform that API

referral calculation for the ‘Proving 7955’ to then calculate Ctlp and Cplp to proving conditions.

[Reference to API Standard: Sections 12.2.5.3 and 12.2.5.4] Calculation PRV#4: Liquid Volume Correction

The volume (density) of the liquid is going to be different at the flowmeter if the temperature and pressure conditions at the flowmeter are not identical to the temperature and pressure conditions at the pipe prover. Hence, another volume correction factor is required.

Using: ISVm = ( )IV C Ctlm plm* *

Where: ISVm = Corrected Metered Volume………………..……… {Menu Data: <”Prv corr metered vol”>}

Ctlm = Correction factor for effect of temperature on fluid at the flowmeter…………..……………

……………………………………………………….……..….{Menu Data: <”Prover CTLm”>}

Cplm = Correction factor for effect of pressure on fluid at the flowmeter…………..………….……

……………………………..………………………….……….{Menu Data: <”Prover CPLm”>}

And: IV = m

CKFN

Where: IV = Meter Volume (in m3)………...…………………….. {Menu Data: <”Prv metered volume”>}

NC = Interpolated pulse count *…………………….………...{Menu Data: <”Prv interp pulses”>}

mKF = The existing factor from the ‘Metering’ 7955 (in pulse/m3)……..…………………………….

………………………………………………………… ……{Menu Data: <”Prv old K factor”>}

* This is the average when using a Brooks Prover; it is not averaged when using other Pipe Provers.


7955 (CH16A/BC) Page 16A.13

Calculation Notes: 1. The values of Ctlm and Cplm are generated using the same method for generating Ctl and Cpl on the

‘Metering’ 7955 (or the combined ‘Metering/Proving’ 7955). Ctl and Cpl are both generated by the API

referral of the Base Density value to metering conditions. The ‘Metering 7955’ must perform that API

referral calculation for the ‘Proving 7955’ to be able to calculate Ctlm and Cplm .

[Reference to API Standard: Sections 12.2.5.3 and 12.2.5.4]

2. The NC term represents an average of the interpolated pulse counts from all of the consecutive good

(passed) prove-runs. The method for calculating an interpolated (corrected) pulse count is explained on

page 16A.10.

Calculation PRV#5: Calibrated Volume Temperature Correction These corrections compensate for thermal and mechanical expansion of the pipe prover. (PRV#5a) Temperature correction for pipe material of Bi-directional and Uni-directional Prover

Using: Ctsp = ( )1+ −e t tb*

Where: Ctsp = Temperature correction factor for steel………... {Menu Data: <“Prover CTS”>}

t = Average of temperatures at prover valves…….. {Menu Data: <“Prv ave prover temp”>}

e = Expansion coefficient (PPM/°C)………………... {Menu Data: <“Prv expansion coeff”>}

tb = Calibration Temperature of Prover……………... {Menu Data: <“Prover cal temp”>}

(PRV#5b) Temperature correction for pipe material of Brooks Compact Prover

Using: Ctsp = ( )[ ] ( )[ ]1 11 1 2 2+ − + −e t t e t tb b* * *

Where: Ctsp = Temperature correction factor for steel……….. {Menu Data: <“Prover CTS”>}

t1 = Average of temperatures at prover valves…….. {Menu Data: <“Prv ave prover temp”>}

t2 = Prover Invar Temperature……………………….. {Menu Data: <“Prover Invar temp”>}

e1 = Area expansion coefficient (ppm/°C)…………… {Menu Data: <“Prv sqr expan coeff”>}

e2 = Linear expansion coefficient (ppm/°C)…………. {Menu Data: <“Prv lin expan coeff”>}

tb = Calibration Temperature of Prover…………….. {Menu Data: <“Prover cal temp”>}

Calculation PRV#6: Calibrated Volume Pressure Correction (for pipe material)

Using: Cpsp = ( )

1p p * d

E * Wa+

−⎛

⎝⎜⎜

⎞

⎠⎟⎟

Where:

Cpsp = Pressure correction factor for steel………….. {Menu Data: <”Prover CPS”>}

p = Average of pressures at prover valves………… {Menu Data: <“Prv ave prover press”>}

pa = Atmospheric pressure (BarA)………………….... {Menu Data: <”Atmos pressure”>}

d = Internal diameter of Prover pipe (mm)…………. {Menu Data: <“Prover pipe diameter”>}

E = Modulus of elasticity (N/m²)…………………….. {Menu Data: <“Modulus of E”>}

W = Wall thickness of prover pipe (mm)………….…. {Menu Data: <“Prv pipe thickness”>}


Page 16A.14 7955 (CH16A/BC)

16A.4.2 Volumetric Prover Proving of a Coriolis Mass Meter (by Mass or Volume)

Prove-run calculations for this scenario are listed here for your convenience. Where appropriate, terms are annotated with the associated software parameters as they are displayed within the 7955 menu system. Unless otherwise stated, these software parameters are to be found in the Prover Archive Session and Run Menus under: <”Proving”>/<”Prover log”>/<”Pipe provers”>. Calculation: PRV#7: Indicated Meter Mass (Coriolis Meter)

Using: mIM =mKf

N

MC

Where: IMm = Indicated Mass (Coriolis Meter)…………………. {Menu Data: <”Prv metered mass”>}

NC = Interpolated Pulse Count (Coriolis Meter)……... {Menu Data: <”Prv interp pulses”>}

KfMm = Existing ‘K factor’ of Coriolis Meter (in mass/pulse or pulse/mass units)………….. ………………………………………………..……. {Menu Data: <”Prv old K factor”>} *

* Parameter as seen on ‘Metering’ 7955

Calculation: PRV#8: Indicated Meter Volume (Coriolis Meter)

Using: mIV = mmIM

ρ

Where: mIV = Indicated Volume (Coriolis Meter)………..…….. {Not in the Menu}

IMm = Indicated Mass (Coriolis Meter)…………………. {See Calculation PRV#7}

mρ = Fluid density at the Meter…………………..….... {Menu Data: <”Meter run density”>} *

* Parameter as seen on ‘Metering’ 7955 Calculation: PRV#9: Corrected Prover Volume

Using: pCV = CplpCtlpCpspCtspVB ****

Where: CVp = Corrected Prover Volume (m³)…………….……. {Menu Data: <”Prover corr volume”>}

VB = Base Volume of Prover (m³)…………………….. {Menu Data: <“Prover volume”>}

Ctsp = Temperature correction factor for steel………... {Menu Data: <“Prover CTS”>}

Cpsp = Pressure correction factor for steel………….…. {Menu Data: <”Prover CPS”>}

Ctlp = Correction factor for effect of temperature on fluid in the Prover…….………….. ……………………………………………….………{Menu Data: <”Prover CTLp”>}

Cplp = Correction factor for effect of temperature on fluid in the Prover…….………….. ……………………………………………….………{Menu Data: <”Prover CPLp”>}

Calculation: PRV#10: Prover Mass

Using: pCM = BpCV ρ*

Where: CMp = Prover Mass (Kg)…………………..….……… {Menu Data: <”Prover corr mass”>}

CVp = Corrected Prover Volume (m³)….….….……. {See Calculation PRV#8}

Bρ = Base density…………………..…………..….. {Menu Data: <”Base density”>}


7955 (CH16A/BC) Page 16A.15

Calculation: PRV#11: New Meter Factor (for Coriolis Meter)

If proving by Mass….

Using: MFNew = m

pIMCM


CMp = Prover Mass (Kg)…………………..….……… {See Calculation PRV#10}

IMm = Indicated Mass (Coriolis Meter)…………….. { See Calculation PRV#7}

Otherwise…

Using: MFNew = m

pIVCV


CVp = Corrected Prover Volume (m3)……...……… {See Calculation PRV#9}

IVm = Indicated Volume (Coriolis Meter)………….. { See Calculation PRV#8}

Calculation Notes: 1. The new ‘Meter factor’ is always calculated at the end of a successful session. It is then shown in the

session part of the Prover Archive even if it is not offered for acceptance or is offered but then rejected.


‘Meter factor’ or offer the new ‘K factor for acceptance to replace an existing meter-run (stream) value.

3. The replaced ‘Meter factor’ value is stored in the Prover Archive menu at the <”Prv old meter factor”>

menu data page Calculation PRV#12: New ‘K Factor’

The ‘K factor’ is a result of the liquid flowmeter proving process. This factor is used when calculating the Indicated Volume flow rate at the flow metering point.

Using: KFNew = KF

MFOld

New

Where: KFNew = New calculated ‘K factor’……….……………. {Menu Data: <”Prv new K factor”>}

KFOld = Previous calculated ‘K factor’…….…………. {Menu Data: <”Prv old K factor”>}

MFNew = New calculated ‘Meter factor’………..…….... {See Calculation PRV#10}

Calculation Notes: 1. The new ‘K factor’ is always calculated at the end of a successful session. It is then shown in the

session part of the Prover Archive even if it is not offered for acceptance or offered but rejected.


‘K factor’ or offer the new ‘Meter factor for acceptance to replace an existing metering-run (stream)

value.


Page 16A.16 7955 (CH16A/BC)

16A.5 Connections: Inputs and Outputs

16A.5.1 Status Inputs Power usage

Refer to the Status Input details in Chapter 2. Status Input common pin

Refer to the Status Input details in Chapter 2. Signal pins (Prover and Valves only)

Use Table 16.1 to find the appropriate function list for your particular set-up

Table 16.1: Pin Table Index

Prover Scheme 1st. Page

Unidirectional 1x4x1 16A.16


Bi-directional 1x4x1 16A.18


Brooks Compact 1x4x1 16A.20


Table 16.2: Status Inputs for Unidirectional Prover (1x4x1 Scheme)

Status Input Function D-type

Pins Remark

1 • Prover detector switch (Start or Stop) Sk2/01

2 • Prover detector switch (Start or Stop) Sk2/02 See note G for details of use

3 • Prover Outlet Valve State (A) SK2/05

4 • Prover Outlet Valve State (B) SK2/06 • Called “Valve 9” in software • Read notes B and F

5 • Metering-point #1 Block Valve State (A) SK2/07

6 • Metering-point #1 Block Valve State (B) SK2/08 • Called “Valve 1” in software • Read notes B and F


8 • Metering-point #2 Block Valve State (B) SK2/10

• Called “Valve 2” in software • Read notes B and F



• Called “Valve 3” in software • Read notes B and F



13 • Metering-point #1 Prover Valve State (A) SK2/21

14 • Metering-point #1 Prover Valve State (B) SK2/22 • Called “Valve 5” in software • Read notes B and F







21 • Metering-point #1 Strainer switch indicator SK2/37




• Read notes B and E

25 • Prover Abort Command SK2/41 • Active=Abort Prove

26 • Prover Ready Indicator SK2/42 • Active=Prover device is ready

IMPORTANT! Status Inputs 13 – 20 relate to the Prover Inlet Valve


7955 (CH16A/BC) Page 16A.17

Table 16.3: Status Inputs for Unidirectional Proving (4x4x4 Scheme)

Status Input Function D-Type

Pins Remark

1 • Prover detector switch (Start or Stop) SK2/01

2 • Prover detector switch (Start or Stop) SK2/02 • See note G for details of use

3 • (Print Current Report) SK2/05

4 • (Maintenance-mode request) SK2/06 • Read note A









13 • Metering-point #1 Prover Valves State (A) SK2/21

14 • Metering-point #1 Prover Valves State (B) SK2/22 • Called “Valve 5” in software • Read notes B and F











• Read notes B and E

25 • Prover Abort Command SK2/41 • Active = Abort Prove

26 • Prover Ready Indicator SK2/42 • Active = Prover device is ready

IMPORTANT! Status Inputs 13 – 20 relate to the Prover Inlet and Outlet Valves

Notes (for Unidirectional and Brooks Compact Prover)

A These functions can be re-mapped by editing a parameter under <“Configure”>/<”Status i/p assign”>

B ‘Local’ flowmeter proving requires all valve related connections to be made on the flow computer that is performing both stream (metering-run) and proving functions.

‘Remote’ flowmeter proving requires valves connections for a specific stream (metering-run) to be made on the remote flow computer.

C The default signal state of each input is inactive (i.e. logic ‘0’) when using positive logic. Status inputs can be configured for negative logic on an individual basis.

D The prover device must maintain an active signal on Status Input #26 for a prove session to begin and for whole of a prove session.

E Unidirectional Prover: Indicator is for a strainer switch input. An active signal indicates the presence of a blockage and will abort a session at the end of a run.

Brooks Compact Prover: Indicator is for an ‘up-stream’ signal. The prover device should only keep the indicator inactive while the piston is in the standby (start-up) position and for the duration of a prove-run, including the launch, for a metering-run (stream).

F Valve status signals are received through paired Status Inputs - nominated as ‘A’ and ‘B’ in tables of pins. Combinations of active and inactive signals are used to differentiate valve states, as guided in Table 16.4 on page 16A.18. NOTE: The Prover Inlet and Outlet Valve connections must be paired in a 4x4x4 system.

G A ‘Start’ and ‘Stop’ pulse can be received through any of the first two Status Inputs. The 7955 Flow Computers have an automatic detection system that requires no configuring.


Page 16A.18 7955 (CH16A/BC)

Table 16.4: Recognised Valve States

‘A’ ‘B’ Valve status Comment

0 0 Failed This indicates the existence of a fault condition

0 1 Close Valve is fully closed

1 0 Open Valve is fully open

1 1 Moving Valve is being re-positioned

Key: ‘1’ = Active, ‘0’ = Non-active {Positive logic assumed}

Table 16.5: Status Inputs for Bi-directional Prover (1x4x1 Scheme)


Pins Comment



3 • (Print Current Report) SK2/05

4 • (Maintenance-mode request) SK2/06 • Read note A



• Called “Valve 1” in software • Read notes B and D










13 • Metering-point #1 Prover Inlet Valve State (A) SK2/21

14 • Metering-point #1 Prover Inlet Valve State (B) SK2/22












22 • Prover Outlet Valve State (B) SK2/38


23 • Prove Abort Command SK2/39 • Active = Abort Prove

24 • Prover Diverter Valve Leak SK2/40 • Active = Leakage detected

25 • Prover Diverter Valve State (A) SK2/41

26 • Prover Diverter Valve State (B) SK2/42

• Called “Valve 10” in software

• Read notes B and D

Notes follow Table 16.6 on page 16A.19


7955 (CH16A/BC) Page 16A.19

Table 16.6: Status Inputs for Bi-directional Prover (4x4x4 Scheme)


Pins Comment




4 • Prover Diverter Leak Indicator SK2/06 • Active = Leak detected














14 • Metering-point #1 Prover Valves State (B) SK2/22


• Read notes B, D and E

















• Active = Abort session due to blockage

25 • Prover Diverter Valve State (A) SK2/41

26 • Prover Diverter Valve State (B) SK2/42 • Read notes B and D

Notes (for Bi-directional Prover)

A These functions can be re-mapped by editing a parameter under <“Configure”>/<”Status i/p assign”> B ‘Local’ flowmeter proving requires all valve related connections to be made on the 7955 flow computer that is

performing both metering-run and proving functions

‘Remote’ flowmeter proving requires valves connections for a specific metering-run be made on the 7955 flow computer that is performing functions for that metering-run

C The default state of each input is non-active (i.e. logic ‘0’) only when using positive logic. Status inputs can be configured for negative logic on an individual basis

D Valve status signals are received through paired Status Inputs (nominated as ‘A’ and ‘B’ in tables above).

Combinations of active and inactive signals are used to differentiate the valve states, as guided in Table 16.4 on page 16A.18.

E In a 4x4x4 system the Prover Inlet and Outlet Valves of a metering-run should be wired in series.


Page 16A.20 7955 (CH16A/BC)

Table 16.7: Status Inputs for Brooks Compact Prover (1x4x1 and 4x4x4 Schemes)

Status Input Function D-type

Pins Remark

1 • Prover detector switch (Start or Stop) Sk2/01

2 • Prover detector switch (Start or Stop) Sk2/02 See note G for details of use


4 • Prover Outlet Valve State (B) SK2/06 • Called “Valve 9” in software • Read notes B and F

















21 • Nitrogen Low SK2/37 • Active = Nitrogen level is low

22 • Upstream Status SK2/38


26 • Prover Ready Indicator SK2/42 • Active = Prover is ready

IMPORTANT! Status Inputs 13 – 20 relate to the Prover Inlet Valve

Note: When using a 1x4x1 system, the Prover Outlet Valve is not under the control of the 7955. It has to be

hand-operated or controlled by some other automated system.


7955 (CH16A/BC) Page 16A.21

16A.5.2 Status Outputs Power usage

Refer to the Status Input details in Chapter 2.

Status Input common pin

Refer to the Status Input details in Chapter 2.

Signal pins (Prover and Valves only)

Use Table 16.8 to find the appropriate function list for your particular set-up

Table 16.8: Index to Status Output Pin Tables

Prover Scheme 1st. Page







Table 16.9: Status Outputs for Unidirectional Proving (1x4x1 Scheme)

Status Outputs Function D-Type

Pins Comment

5 • Metering-point #1 Block Valve Control (A) SK2/29

6 • Metering-point #1 Block Valve Control (B) SK2/30


• Read notes A and C













13 • Metering-point #1 Prover Inlet Valve Control (A) SK1/02

14 • Metering-point #1 Prover Inlet Valve Control (B) SK1/03















21 • Prover Outlet Valve Control (A) SK1/34

22 • Prover Outlet Valve Control (B) SK1/35



25 • Prover Start Command SK1/38 • Active = Start Proving

Notes follow Table 16.10 on page 16A.22


Page 16A.22 7955 (CH16A/BC)

Table 16.10: Status Outputs for Unidirectional Proving (4x4x4 Scheme)

Status Outputs Function D-type

Pins Comment

5 Metering-point #1 Block Valve Control (A) SK2/29

6 Metering-point #1 Block Valve Control (B) SK2/30

• Called “Valve 1” in software • Read notes A and C










13 Metering-point #1 Prover Valves Control (A) SK1/02

14 Metering-point #1 Prover Valves Control (B) SK1/03

• Called “Valve 5” in software • Read notes A, C and E










25 Start Prove / Run Command SK1/38 • Active = Start Proving. Read Note D

IMPORTANT!! Status Outputs 13 – 20 relate to the Prover Inlet and Outlet Valve

Notes (for Unidirectional Prover)

A ‘Local’ flowmeter proving requires all valve related connections to be made on the flow computer that is performing both stream (metering-run) and proving functions

‘Remote’ flowmeter proving requires valves connections to be made on the remote flow computer

B The default signal state of each input is inactive (i.e. logic ‘0’) when using positive logic. Status inputs can be configured for negative logic on an individual basis

C Valve control commands are issued through a paired Status Outputs (nominated as ‘A’ and ‘B’ in tables

above and below). Combinations of active inactive signals from the paired Status Outputs are used to differentiate valve commands, as shown in Table 16.15

D Status Output #25 is kept active for the whole of the initialisation phase of a proving session and kept

active for the whole of a prove-run. It is inactive between prove-runs.



7955 (CH16A/BC) Page 16A.23

Table 16.11: Status Outputs for Brooks Compact Proving (1x4x1 and 4x4x4 Schemes)

Status Outputs Function D-type

Pins Comment













13 Metering-point #1 Prover Valve(s) Control (A) SK1/02

14 Metering-point #1 Prover Valve(s) Control (B) SK1/03

• Called “Valve 5” in software • Read notes A, C and F










21 Start Hydraulic Pump SK1/34 • Active = Retract piston to stand-by

22 Stop Hydraulic Pump SK1/35 • Active = Stop (piston retracted)

23 Plenum pressure vent SK1/36 • Active = ‘Open Vent’ command

• Read note D

24 Plenum pressure charge SK1/37 • Active = ‘Charge’ command

• Read note D

25 Start Prove / Run Command SK1/38 • Active = Start Proving

Notes (for Brooks Compact Prover)



B The default signal state of each input is inactive (i.e. logic ‘0’) when using positive logic. Status inputs can be configured for negative logic on an individual basis


above and below). Each valve is allocated a separate pair. Combinations of active inactive signals from the paired Status Outputs are used to differentiate valve commands, as shown in Table 16.15

D Plenum pressure can be either increased or decreased by activating Status Outputs #24 (to increase)

and #23 (to reduce). During the stabilisation phase, the 7955 Flow Computer monitors plenum pressure from a mA Input and automatically uses these status outputs to achieve a user-defined level

E Status Output #25 is kept active for the whole of the initialisation phase of a proving session and kept

active for the whole of a prove-run. It is inactive between prove-runs.

F When using a 1x4x1 system, the Prover Outlet Valve is not under the control of the 7955. It has to be

hand-operated or controlled by some other automated system.

In a 4x4x4 system the Prover Inlet and Outlet Valves of a metering-run should be wired in series.


Page 16A.24 7955 (CH16A/BC)

Table 16.12: Status Outputs for Bi-directional Prover (1x4x1 Scheme)

Status Output Function D-type

Pins Comment





8 • Metering-point #2 Block Valve Control (B) SK2/44 • Called “Valve 2” in software • Read notes A and C






14 • Metering-point #1 Prover Inlet Valve Control (B) SK1/03 • Called “Valve 4” in software • Read notes A and C

15 • Metering-point #2 Prover Inlet Valve Control(A) SK1/04

16 • Metering-point #2 Prover Inlet Valve Control(B) SK1/18 • Called “Valve 5” in software • Read notes A and C

17 • Metering-point #3 Prover Inlet Valve Control(A) SK1/19

18 • Metering-point #3 Prover Inlet Valve Control(B) SK1/20





21 • Prove Diverter Control (A) SK1/34

22 • Prove Diverter Control (B) SK1/35

• Called “Valve 8” in software • Read notes A and D

23 • Prover Outlet Valve Control (A) SK1/36

24 • Prover Outlet Valve Control (B) SK1/37



Notes are on page 16A.25

Table 16.13: Status Outputs for Bi-directional Prover (4x4x4 Scheme)

Status Output Function D-type

Pins Comment

















13 • Metering-point #1 Prover Valves Control (A) SK1/02

14 • Metering-point #1 Prover Valves Control (B) SK1/03


• Read notes A, C and E













21 • Prove Diverter Control (A) SK1/34

22 • Prove Diverter Control (B) SK1/35



23 • Prove Detector Select (A) SK1/36

24 • Prove Detector Select (B) SK1/37 • Read notes A and D



7955 (CH16A/BC) Page 16A.25

Notes for Bi-directional Prover:



B The default state of each output is non-active (i.e. logic ‘0’ only when using positive logic). Status outputs can be configured for negative logic on an individual basis


above and below). Combinations of active and inactive signals from paired status outputs are used to differentiate valve commands, as shown in Table 16.15

D Calibrated volume selection is signalled to the prover through paired Status Outputs (#23 and #23). The combination of active and inactive outputs tell the prover device which calibrated volume should be used for a prove session. See Table 16.15 for the status output logic.

When using a bi-directional Prover (1x4x1 scheme), external arrangements are necessary to signal it, unless the 7955 is a ‘Metering’ and ‘proving’ Flow Computer


Table 16.14: Calibrated Volume Selection

‘A’ ‘B’ Volume selected Comment

0 0 BD • Calibrated volume between detector switch ‘B’ and ‘D’

0 1 BC • Calibrated volume between detector switch ‘B’ and ‘C’

1 0 AD • Calibrated volume between detector switch ‘A’ and ‘D’

1 1 AC • Calibrated volume between detector switch ‘A’ and ‘C’

Table 16.15: Valve Commands

‘A’ ‘B’ Valve

Command Comment

0 0 Idle • Valve remains at present position

0 1 Close • Fully close valve

1 0 Open • Fully open valve

1 1 (Not used) • Never issued from the 7955.

Key: ‘1’ = Active, ‘0’ = Non-active {Positive logic assumed}


Page 16A.26 7955 (CH16A/BC)

16A.5.3 Analogue Inputs Several metering (stream) measurements are used in the prover calculations that are performed on the ‘Proving’ 7955 Flow Computer:

• Temperature (at the Prover Inlet valve) *…………........… All Provers

• Pressure (at the Prover Inlet valve) *...........…………...… All Provers

• Temperature (at the Prover Outlet valve) *………………. Bi-directional piper prover only

• Pressure (at the Prover Outlet valve) *.…………….…….. Bi-directional piper prover only

• Brooks Plenum Pressure.................…………...………..... Brooks Compact Prover only

* When there is just one sensor at a valve, you must use that sensor input for both the

outlet and inlet measurements.

The ‘Live’ measurements are either:

• directly input to the combined ‘Proving’ and ‘Metering’ 7955 Flow Computer (for ‘local’ proving) or • directly input to the ‘Metering’ Flow Computer and then transmitted to the ‘Proving’ Flow Computer

Analogue inputs on a 7955 Flow Computer are not dedicated to a specific measurement. Connect each sensor to an unused Analogue Input (as guided in Chapter 2) and then configure that Analogue Input and measurement task by using an appropriate Wizard.

Section Details covered

Chapter 2 Connecting field transmitters to a 7955

Chapter 10 About using Wizards

16A.5.4 Pulse (Turbine) Inputs A guide to connecting a supported volumetric/mass flowmeter to the 7955 is in Chapter 2. The subsequent configuration work is covered in the Chapter 11.

16A.5.5 ‘Remote’ Proving Connection Summary Summary of 7955 Flow Computer connections as required for ‘remote’ proving:

‘Prover’ Flow Computer ‘Metering’ Flow Computer

• Status Inputs for Prover outputs • Status Inputs for valve monitoring

• Status Outputs for Prover inputs • Status Outputs for valve control

• Pulse inputs for flowmeter output • Pulse inputs for flowmeter output

• Port for MODBUS communications with ‘Metering’ Flow Computer

• Port for MODBUS communications with ‘Prover’ Flow Computer


7955 (CH16A/BC) Page 16A.27

16A.6 Valve Control and Monitoring This section explains how the 7955 can position valves to allow flow into a ‘Prover-loop ’ and then return them to a position for normal flow. Configuration task details for valves are also provided.

16A.6.1 Overview Valves can be controlled and monitored either by:

• a 7955 performing both ‘Proving’ and ‘Metering’ functions (i.e. ‘local’ proving) or • a 7955 performing mostly ‘Proving’ functions but instructing a second 7955 to do the valve

controlling. Valve states are received by the ‘Metering’ 7955 and passed back to the ‘Proving’ 7955

In both cases, valves can be controlled automatically, manually or a mixture of the two.

16A.6.2 Fully Automatic Valve Control and Monitoring The metering-run Block valve, Prover Isolation valve and Prover outlet valve are all connected to a 7955 by means of Status Inputs and Outputs.

Stream MeterProver Inlet

Stream block

Prover outlet

Flow direction

To Prover From Prover

The 7955 allocates two Status Inputs and two Status Outputs to each valve.

Status Inputs are used to monitor the state of each valve. Combinations active or inactive signals from paired inputs are interpreted to obtain a valve state. (See “valve states” for details). Status Outputs are used to command each valve (controller) to re-position themselves and, therefore, alter the flow path. Commands are in the form of a combination active or inactive pulsed outputs. (See “valve commands format” for details). At the start of a prove session, flow is re-directed into a Prover-loop by opening both Prover valves and then closing the Metering-run Block valve. After a prove session is completed flow is stopped from entering the Prover-loop by opening the Steam Block valve and closing both Prover valves. The diagram below shows these sequences.

Open prover outlet valve

Open prover inlet valve

Close stream block valve

Timeout

Timeout

Timeout

Valves aligned Valve failure

Open stream block valve

Close prover inlet valve

Close prover outlet valve

Timeout

Timeout

Timeout

Valves returned Valve failure

VALVE ALIGNMENT VALVE RETURN

Valve positioned

Valve positioned

Valve positioned

Valve positioned

Valve positioned

Valve positioned

Both sequences in a prove-run are fixed but the time between issuing commands can be user-defined. Valves also have a user-defined amount of time to respond to commands. Valve time-outs always cause a prove-run to be aborted.

Note: Valves must be in the correct initial position prior to starting a prove session – all block valves for the flowing streams must be open and all divert valves must be closed. Failure to observe this will result in a “Prover Abort Init i” alarm.


Page 16A.28 7955 (CH16A/BC)

16A.6.3 Fully Manual Valve Control and Monitoring There are no physical connections to valves and valve time-outs are switched off.

Prior to a prove session, valves must be re-positioned using another (off-line) system to direct flow into the prover-loop. After starting a prove session, the operator then simply follows on-screen prompts to answers ‘yes’ (or ‘no’) to confirm to the 7955 that a valve has been opened or closed by some other means. Pressing ‘no’ always aborts a prove session.

At the close of a prove session, valves should be returned to their original positions using another (off-line) system and the operator, again, simply follows on-screen prompts to answers ‘yes’ (or ‘no’) to confirm the state of each valve.

The valve ‘alignment’ and ‘return’ sequences are identical to the automatic process.

16A.6.4 Mixture of Automatic/Manual Valve Control and Monitoring It is also possible to have some valves under automatic control the remainder under manual control. This is determined during the configuration task as detailed in Section 16A.6.7

Warning! There are data locations within the <“Valves”> menu to: (a) manually issue commands to a valve (See notes), (b) monitor commands being issued by automatic control (during a prove) and (c) monitor valve states. Notes: 1. Operators can select, at their leisure, a ‘valve command’ for any one of four

connected valves in any order. This can be done either at the front panel keyboard or over a serial communications (MODBUS network) link. Manual commands are transmitted, as pulses, by the 7955 to valve controllers when the operator selects a valve command.

2. Do not issue commands to valves in this way unless it is absolutely necessary.

However, monitoring these locations can be useful.

16A.6.5 Valve Command Formats Commands are transmitted through a paired status outputs (nominated ‘A’ and ‘B’). Combinations of a active (logic ‘high’) or inactive (‘low’) signals are issued simultaneously on each output to differentiate commands. Table 16.16 shows the valve commands that should be recognised by a valve controller.

Table 16.16: Status output logic for valve commands

‘A’ ‘B’ Valve Command Command Use

0 0 Idle • Valve remains at present position

0 1 Close • Fully close valve or

• Rotate 4-way diverter valve to the reverse position

1 0 Open • Fully open valve or • Rotate 4-way diverter valve to the forward position

1 1 (Not used) • Never issued by the 7955.

(Positive Logic by Default)

Note: Only Bi-directional ‘prover-loops’ feature a 4-way diverter valve


7955 (CH16A/BC) Page 16A.29

Two valve command signalling methods are supported: Pulse mode and Level mode. 1. Open/close valve commands with the “pulse” drive method

Paired status outputs issue a combination of two short pulsed (active) signals to the valve (controller). The 7955 regards the valve as being fully opened or closed when the valve state is interpreted as “open” (or “closed”).

Figure 16-2: Successful closure of a valve (“pulse” drive method)

Valve"Open"

command

Status output (A)

Status output (B)

Status input (A)

Status input (B)

valve response timeout

userdefinedduration

Valve "opened" state

2. Open/close valve commands with the “level” drive method

Paired status outputs issue a combination of two pulsed signals to the valve (or, most likely, a valve controller). Signal levels are normally sustained until the valve state is interpreted by the 7955 as “open” (or “closed”).

Figure 16-3: Successful closure of a valve (“level” drive method)

Valve "open" command

Status output (A)

Status output (B)

Status input (A)

Status input (B)

Valve "opened" state

valve response timeout


Page 16A.30 7955 (CH16A/BC)

16A.6.6 Valve States Paired status inputs are monitored to check the result of an issued command. Valve states are transmitted through paired status inputs (nominated ‘A’ and ‘B’). Combinations of a active (logical ‘high’) or inactive (logical ‘low’) signal are received simultaneously on each input to differentiate the different states. Table 16.17 shows all the valve states that should be communicated by a valve controller:

Table 16.17: Status input logic for valve states

‘A’ ‘B’ Valve status (as displayed) Comment

0 0 Failed This indicates a fault condition




Note: No configuration work is required for this feature if using default positive logic

16A.6.7 Configuration Details (for the ‘Proving’ 7955 and ‘Metering’ 7955)

1. Navigate to this menu: <“Configure”>/<“Valves”>

The expression <“Configure”>/<“Valves”> translates into the following keyboard sequences:

(1) Press the MAIN-MENU Key

(2) Use the DOWN-ARROW key to scroll through several pages. Halt when “Configure” appears.

(3) Press the blue key that is alongside that description.

(4) Use the DOWN-ARROW key to scroll through several pages. Halt when the description “Valves” appears.


2. Work through this menu data list for each valve


Valve drive mode • Choose between “Pulse” drive mode and “Level” drive mode

Valve duration • Enter a value for how long a pulse (of a valve command) is to be sustained. Default time is 0 (machine cycles)

Valve timeout • Enter the period allowed for the valve to be re-positioned. Use 0 seconds when using manual valve control. Default time is 0 (machine cycles)

Valve control • Choose between “Automatic” control or “Manual” control

Note: Valves designations are listed in Section 16A.5

3. Navigate to this menu: <“Configure”>/<“Prover”>

4. Locate this menu data: <“Prv auto rtn valves”>

5. Select “Yes” or “No”

“Yes” The 7955 is fully responsible for managing the return of (supported) valves to their original pre-prove positions at the end of a prove session. No interaction is required.

“No” Valves are re-positioned by another (off-line) system at the end of a prove session. On-screen prompts will appear for an operator to confirm that valves are in their original pre-prove positions.

(Ignore steps 6 and 7 if relying on automatic valve control and monitoring)


7955 (CH16A/BC) Page 16A.31

6. Locate this menu data: <“Prv valve confirm”>

7. Select a mode for confirming the position of valves

“Ignore” 7955 relies on valve state feedback through paired status outputs

“Grouped” 7955 prompts for a single key-press to confirm that all valves are in position

“Individually” 7955 prompts for a single key-press to confirm that a particular valve is in position (End of this configuration task)

You can now proceed to the next section to continue the configuration.


Page 16A.32 7955 (CH16A/BC)

16A.7 Configuration Tasks: Proving Details

This section explains how to configure basic details about the prover device and how a proving session should operate. There are separate communication set-up tasks for ‘local’ proving and ‘remote’ proving. Use Table 16.18 to identify the appropriate configuration tasks Mini-Index 16A.7.1 Configuration Task #1: Metering-run Measurement Functions……..….…..……….. 16A.33

16A.7.2 Configuration Task #2: Common Prover details……………………………………… 16A.36

16A.7.3 Configuration Task #3a: Bi-directional /Unidirectional Prover details……………… 16A.40

16A.7.4 Configuration task #3b: Brooks Compact Prover details………………………..…… 16A.41

16A.7.5 Configuration task #4a: Serial Port Communications (‘local’ prove………………… 16A.43

16A.7.6 Configuration task #4b: Serial Port Communications (‘remote’ prove)…………….. 16A.44

Table 16.18: Configuration tasks required for each prover

Prover Type Local/Remote Proving

Configuration Tasks

Unidirectional Local 1 2 3a 4a

Unidirectional Remote 1 2 3a 4b

Bi-directional Local 1 2 3a 4a

Bi-directional Remote 1 2 3a 4b

Brooks Compact Local 1 2 3b 4a

Brooks Compact Remote 1 2 3b 4b

Note: “Local” = Combined ‘Metering/Proving’ 7955, “Remote” = Separate ‘Metering’ 7955 and Proving 7955


7955 (CH16A/BC) Page 16A.33

16A.7.1 Configuration Task #1: Metering-run Measurement Functions (Unless indicated, this task is to be attempted on the 7955 performing the ‘Metering’ functions).


1. Ensure that the Metering-run measurement tasks are configured

Measurement task Menu data pages to check Which 7955?

Flowmeter details Various – See Chapter 11 Proving and Metering

Flow rates Various – See Chapter 11 Metering

Metering-run density Meter density Metering

Base density Base density Metering

Metering-run temperature Meter temperature Metering

Metering-run pressure Meter pressure Metering

Note: Refer to Chapters 3, 10 and 11 for details of these measurements

2. Set-up Plenum Pressure Monitoring and Control (Brooks Compact Prover only)

Objectives: • Review the Plenum pressure control set-up • Receive Plenum pressure measurements from a field transmitter. • Establish the target level of Plenum pressure needed for a proving session to begin. • Define dead-band limits for controlling and maintaining Plenum pressure. • Define limits for checking that Plenum pressure is sufficient before and during each run.

What to do: (2a) Review Plenum Pressure Control set-up

Ensure that Status Outputs #6 and #16 are physically connected to the correct inputs on the Brooks Compact Prover. Refer to the Section 16A.5.2 (on page 16A.21) if this has not been established.

(2b) Ensure that one Analogue Input or HART/Analogue Input is wired and configured to receive

Plenum Pressure measurements.

If using HART… Use Chapter 17 to set-up HART Inputs and then continue with step 2c

If using mA…

Use Chapter 2 for wiring information, Chapter 11 for mA Input configuration details and then continue with step 2c

(2c) Navigate to: <“Configure”>/<“Pressure”>/<”Prover pressure”>/<”Prv plenum pressure”> (2d) Work through Table 16.19.

Table 16.19: Plenum pressure measurement parameters

Menu Data * (as displayed) Instructions and Comments

Plenum press @ 20mA ‘SET’ a value for the highest measurement supported by the transmitter

Plenum press @20mA ‘SET’ a value for the lowest measurement supported by the transmitter

Plenum press source Change the selection to the option name that corresponds to the mA-type Analogue Input or HART Input

Prove plenum press Change the status to be “Live”

* Abbreviation used: “Press” = Pressure


Page 16A.34 7955 (CH16A/BC)

(Step 2 continued …) (2e) Navigate to this menu: <“Configure”>/<“Prover”>/<“Brooks compact”>

(2f) Work through Table 16.20

Table 16.20: Brooks Compact Prover Device Parameters

Menu Data (as displayed) Instructions and Comments

Plenum press timeout

‘SET’ the length of time allowed for Plenum pressure to be stabilised within the control limits and/or alarm limits.

A session is aborted if Plenum pressure is outside these limits when this time-limit expires.

Prv plenum const R ‘SET’ a value for the Nitrogen spring pressure constant ‘R’ if the Plenum pressure target is to be calculated.

Plenum press target ‘SET’ a value or change the state to “Live” for the 7955 calculate a target value. Calculation = (<”Meter pressure”> / <”Prv plenum const R“>)

Plenum press LO lmt

‘SET’ the lower limit - a negative value - to be used when establishing a sufficient level of Plenum pressure for a session. ‘Charge’ and ‘Vent’ controls (Status Outputs) are automatically used by the Flow Computer to attain a target level. The limit is expressed as a percentage below the target level.

Plenum press HI lmt

‘SET’ the upper limit value - a positive value - to be used when establishing a sufficient level of Plenum pressure for a session. ‘Charge’ and ‘Vent’ controls (Status Outputs) are automatically used by the Flow Computer to attain a target level. The limit is expressed as a percentage above the target level.

Plenum P alm LO lmt

‘SET’ a limit value - a negative value - for raising an alarm when the Plenum pressure is a percentage below the target level. The alarm has no effect during a prove run but the Flow Computer will delay the next prove run until back within limits.

Plenum P alm HI lmt

‘SET’ a limit value - a positive value - for raising an alarm when the Plenum pressure is a percentage above the target level. The alarm has no effect during a prove run but the Flow Computer will delay the next prove run until back within limits.

3. Prover Inlet and Outlet Temperature

Objectives: • Get scaled temperature measurement values.

What to do: (3a) Navigate to this menu: <“Configure”>/<“Temperature”>/<“Prover temp”>

(3b) Work through Table 16.21.

Table 16.21: Inlet/Outlet Prover Temperature Parameters


Inlet temp @ 20mA ‘SET’ a value for the maximum Temperature that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Inlet temp @ 0/4mA ‘SET’ a value for the minimum Temperature that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Inlet temp src Edit the selection to be the description that corresponds to the input used by the sensor. (See 16A.5.3 on page 16A.26 for connection information)


7955 (CH16A/BC) Page 16A.35

(Step 3c continued…)


Prover in temp LO lmt ‘SET’ a lower limit for the scaled Inlet Temperature value. An alarm will be raised when this lower limit is exceeded.

Prover in temp HI lmt ‘SET’ a higher limit for the scaled Inlet Temperature value. An alarm will be raised when this higher limit is exceeded.

Inlet temp FB type (Optional) Select a fallback function - “Last good value” or “Fallback value” - for when the transmitter can not provide a live value.

Inlet temp FB val (Optional) ‘SET’ a value for the “Fallback value” function (if it is selected).

Inlet temp offset (Optional) Use this for on-line calibration of the transmitter

Prover inlet temp Change the status to be “Live”.

Outlet temp @ 20mA ‘SET’ a value for the maximum Temperature that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Outlet temp @ 0/4mA ‘SET’ a value for the minimum Temperature that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Outlet temp src Edit the selection to be the description that corresponds to the input used by the sensor.

Prover out temp LO ‘SET’ a low limit for the scaled Inlet Temperature value. An alarm will be raised when this lower limit is exceeded.

Prover out temp HI ‘SET’ a high limit for the scaled Inlet Temperature value. An alarm will be raised when this higher limit is exceeded.

Outlet temp FB type (Optional) Select a fallback function - “Last good value” or “Fallback value” - for when the transmitter can not provide a live value.

Outlet temp FB val (Optional) ‘SET’ a value for the “Fallback value” function (if it is selected).

Outlet temp offset (Optional) Use this for on-line calibration of the transmitter.

Prover outlet temp Change the status to be “Live”.

(End of configuration task #1)


Page 16A.36 7955 (CH16A/BC)

16A.7.2 Configuration Task #2: Common Prover details (Unless indicated, this task is to be attempted on the 7955 performing the ‘Proving’ functions).

Objectives: • Identify the type of Prover. • Nominate whether to prove by volume or by mass. Various flowmeter proving scenarios are

supported, as illustrated by the proving calculations shown in Section 16A.4 (on page 16A.11) • Provide fundamental information about that Prover. • Set limits for the ‘Meter Factor’ validation process and the Prover-loop stabilisation checks. • Set time-outs for the various proving events. • Provide optional information for the printable Prover report.

What to do:


1. Navigate to this menu: <“Configure”>/<“Prover”>/<”Common prv details”>

2. Work through Table 16.22 (some localised menu searching is required)

Table 16.22: Common prover basic details


Prover type

Identify the type of Prover (and the calibration volume). (The Bi-directional option texts all have a two lettered code. These letters determine the base (calibrated) volume to be used. For example, “BD” is the base (calibrated) volume between detector switch ‘B’ and detector switch ‘D’.)

Prove by Vol Mass Nominate whether to prove by volume or by mass. See Section 16A.4 (on page 16A.11) if you information on flowmeter proving scenarios.

Prv I/O assignment Identify the type of Prover. This action selects a specific valve control and monitoring scheme.

Prover pipe diameter

‘SET’ a value for the inner diameter of the ‘Prover-loop ’ pipe, unless using the Brooks Compact Prover.

(Selecting a Brooks Compact Prover will trigger the copying of a value from a built-in look-up table.)

Prv pipe thickness

‘SET’ a value for the thickness of the ‘Prover-loop’ pipe, unless using the Brooks Compact Prover.

Selecting a Brooks Compact Prover will trigger the copying of a value from a built-in look-up table.

Modulus of E ‘SET’ a value for the modulus of elasticity.

Prover cal temp ‘SET’ a value for the temperature at which the Prover was calibrated.

Site name (Optional) Edit a site name to be included in the Prover Report.

Meter serial number (Optional) Edit a text label to be included in the Prover Report.

Meter number (Optional) Edit a text label to be included in the Prover Report.

3. Navigate to this menu: <“Configure”>/<“Prover”>/<”Common prv operatn”>

4. Work through Table 16.23 (Some menu searching is required)

Table 16.23: Common prover operation details


Prover operation Select the form of interaction between the operator and the ‘Proving’ 7955

Prv calc select Select whether to calculate a new ‘Meter Factor’ or a new ‘K Factor’

Prover max runs Select the total number of prove-runs for a prove session

Required good runs Select the number of consecutive good (passed) prove-runs required for a successful proving session. (Read note ‘A’)


7955 (CH16A/BC) Page 16A.37

(Step 4 continued…)


Prv max MF deviation

‘SET’ an upper limit (%) for the deviation of calculated factor values

This limit check and the deviation calculation is performed as the first part of the ‘Meter Factor’ validation process. (Read note ‘A’) The 7955 deviation calculation involves the highest and lowest factor values. (Read note ‘B’) Exceeding the limit does not raise an alarm but a new attempt is made to get consecutive good (passed) prove-runs from the remaining session.

Note: A zero value does not switch off this limit check.

Prv meter factor LO

‘SET’ a lower limit for the average of factor values from a completed sequence of consecutive good (passed) prove-runs.

This limit check is performed as the second part of the ‘Meter Factor’ validation process but only if the deviation index is sufficient.

Read notes ‘B’ and ‘C’

Prv meter factor HI

‘SET’ an upper limit for the average of factor values from a completed sequence of consecutive good (passed) prove-runs.

This limit check is performed as the second part of the ‘Meter Factor’ validation but only if the deviation index is sufficient.

Read notes ‘B’ and ‘C’

Prv interp pulse dev

‘SET’ an upper limit (%) for the deviation of the pulse counts from a completed sequence of consecutive good prove-runs.

This limit check and the deviation calculation is performed as the final part of the ‘Meter Factor’ validation process but only if previous checks did not fail. (Read note ‘A’) The 7955 deviation calculation involves the highest and lowest pulse counts. (Read note ‘D’) Exceeding the limit does not raise an alarm but a new attempt is made to get consecutive good (passed) prove-runs from the remaining session.

Note: A zero value does not switch off this limit check.

Prover start delay ‘SET’ a value for the maximum amount of time allowed for the ‘displacer’ to reach the ‘start’ detector switch.

Note: A zero value represents 0 seconds.

Prover start timeout

‘SET’ a value for the maximum amount of time allowed for the period between: (a) the 4-way diverter valve being in the correct position and (b) the ‘displacer’ (sphere or piston) being launched.


THIS MENU DATA IS FOR A BI-DIRECTIONAL PROVER.

Prover run timeout

‘SET’ a value for the maximum amount of time allowed for the period between: (a) the displacer reaching the ‘start’ detector switch and (b) the displacer reaching the ‘end’ detector switch.


Prv inter-run delay ‘SET’ a value for the maximum allowed time between each prove-run.


Prover end delay

‘SET’ a value for the maximum allowed time for the period between: (a) the ‘displacer’ reaching the ‘end’ detector switch and (b) the ‘displacer’ reaching the end of the Prover-loop.


Prv temperature diff ‘SET’ a limit for the maximum allowed difference between the temperature at the flow metering point and the averaged temperatures at the Prover Inlet and Outlet valves. (Read note ‘F’)

Prv pressure diff ‘SET’ a limit for the maximum allowed difference between the pressure at the flow metering point and the averaged pressures at the Prover Inlet and Outlet valves. (Read note ‘F’)


Page 16A.38 7955 (CH16A/BC)



Prv flow rate diff

‘SET’ a value for:

(a) the maximum allowed difference between two consecutive metering-run Indicated Volume flow rate measurements. (Read note ‘E’)

(b) the maximum allowed difference between the metering-run Indicated Volume rate and the Prover volume rate during a machine cycle. (Read notes ‘F’ and ‘G’)

Prv stable timeout ‘SET’ a period for the prover-loop to stabilise

Prv stable temp diff ‘SET’ a value for the maximum allowed difference between the temperature at the flow metering point and the averaged temperatures at the Prover Inlet and Outlet valves. (Read note ‘E’)

Prv stablepress diff ‘SET’ a value for the maximum allowed difference between the pressure at the flow metering point and the averaged pressures at the Prover Inlet and Outlet valves. (Read note ‘E’)

Prv stable flow diff ‘SET’ a value for the maximum allowed difference between the rate of flow at the metering-point and the rate of flow in the prover-loop. (Read note ‘E’)

Notes: A ‘Meter Factor’ validity checks occur when there is a completed sequence of consecutive good (passed)

prove-runs as determined by <”Min good runs”>. A session is automatically finished when all validation checks are successful.

B A ‘Meter Factor’ deviation calculation is performed during a ‘Meter Factor’ validity check.

Using: MFR =( )MF MF

MFHigh Low

Ave

−*100

Where: MFR = Deviation index (%)…………....…….. {Menu Data: <”Prv MF deviation”>}

MFHigh = Highest ‘Meter Factor’ from all good prove-runs in the session so far.

MFLow = Lowest ‘Meter Factor’ from all good prove-runs in the session so far.

And: MFAve =( )MF MFHigh Low−

2

C Exceeding this limit does not raise an alarm but a new attempt is made to get a complete sequence of

consecutive good (passed) prove-runs from the remaining session. Keeping within the HI and LO limit will immediately end a session and class it as successful.

D A pulse count deviation calculation is performed during a ‘Meter Factor’ validity check.

Using: NCR =( )NC NC

NCHigh Low

Ave

−*100

Where: NCR = Pulse count deviation (%)………………...….... {Menu Data: <”Prv interp pulse dev”>}

NCHigh = Highest pulse count from all good prove-runs in the session so far.

NCLow = Lowest pulse count from all good prove-runs in the session so far.

And: NCAve =( )NC NCHigh Low−

2


7955 (CH16A/BC) Page 16A.39

(Notes continued…)

E This limit is checked every machine cycle during the stabilisation phase. Exceeding the limit will not raise an alarm but it will, if stability is not already achieved, trigger a new attempt to detect stability for 10 consecutive cycles during the remainder of the phase.

F This limit is checked once after a prove-run is completed. Exceeding the limit will raise an alarm and

record the prove-run as a failure. A new attempt is made to get the required number of consecutive good (passed) prove-runs from the remainder of the session.

G The Prover Volume flow rate is calculated following the completion of a prove-run. It is used for a

percentage based comparison with the metering-run Indicated Volume flow rate.

Using: CVRP =CV

tP * 3600

Where: CVRP = Corrected Volume flow rate in prover-loop (in m3/hour)…………{Not in the menu}

CVP = Corrected Calibrated Prover Volume (in m3)

t = Duration of prove-run (in seconds)…………………………………{Not in the menu}


Page 16A.40 7955 (CH16A/BC)

16A.7.3 Configuration Task #3a: Bi-directional /Unidirectional Prover details (Unless indicated, this task is to be attempted on the 7955 performing the ‘Proving’ functions).


1. Navigate to this menu: <“Configure”>/<“Prover”>/<”Uni/bi pipe prover”>

The expression <“Configure”>/<“Prover”> translates into the following keyboard sequences:




(4) Use the DOWN-ARROW key to scroll through several pages. Halt when the description “Prover” appears.


2. Work through Table 16.24.

Table 16.24: Bi-directional /Unidirectional Prover details


Prover volume uni/AC ‘SET’ a value for the precise base (calibrated) volume of liquid between detector switch ‘A’ and detector switch ‘C’.

Prover volume AD ‘SET’ a value for the precise base (calibrated) volume of liquid between detector switch ‘A’ and detector switch ‘D’. THIS IS NOT APPLICABLE TO A UNIDIRECTIONAL PROVER.

Prover volume BC ‘SET’ a value for the precise base (calibrated) volume of liquid between detector switch ‘B’ and detector switch ‘C’. THIS IS NOT APPLICABLE TO A UNIDIRECTIONAL PROVER.

Prover volume BD ‘SET’ a value for the precise base (calibrated) volume of liquid between detector switch ‘B’ and detector switch ‘D’. THIS IS NOT APPLICABLE TO A UNIDIRECTIONAL PROVER.

Prv metered volume This shows the base (calibrated) volume that the displacer will travel through. Values are copied from the entered volume data. The selection of the value to copy is determined from the setting for <“Prover type”>.

Prv expansion coeff ‘SET’ a value for the Prover Expansion Coefficient. (See Section 0 on page 16A.12 for use in 7955 calculations)

(End of configuration task #3a)


7955 (CH16A/BC) Page 16A.41

16A.7.4 Configuration task #3b: Brooks Compact Prover details (This task is to be attempted on the 7955 Flow Computer that is performing the ‘Proving’ functions). Follow these instructions:

1. Navigate to the menu: <“Configure”>/<“Prover”>/<”Brooks compact”>


Table 16.25: Brooks Compact Prover details


Brooks size

Selecting a size will trigger the copying of default values from a look-up table to various parameters. (See Table 16.26 below)

Parameters affected, unless using “Other” size option:

1. <”Prv plenum const R”> 2. <”Prv upstream multipl”> 3. <”Prv pipe thickness”> 4. <”Prover pipe diameter”>……………………. (Flow tube ID (inches))

Note: It is necessary to ‘SET’ values for these parameters if using the “Other” size option.

Prover tube material

Selecting a material option will trigger the copying of default values from a look-up table to several parameters. (See Table 16.27 below )

Parameters affected, unless using “Other” material option:

1. <”Modulus of E”>…………………………………(Modulus of elasticity) 2. <”Prv sqr expan coeff”>….…(Square coefficient of expansion per °F)

Note: It is necessary to ‘SET’ values for these parameters if using the “Other” material option.

Prv lin expan coeff ‘SET’ a value for the linear expansion coefficient.

Brooks vol downstrm ‘SET’ a value for the Base Volume down-stream of the Prover.

Brooks vol upstream Either ‘SET’ a value or change the status to “Live” to get the Base Volume calculated by the 7955. The calculation is ( <”Prv upstream multipl”> * <”Brooks vol downstream”>)

Prv metered volume

The value displayed will depend on the selection made for the position of the (turbine) flowmeter.

Up-stream: Value is copied from <”Brooks vol upstream”>

Down-stream: Value is copied from <”Brooks vol downstream”>

Flow meter position Selecting the position will affect the value displayed by <”Prv metered volume”>

Prv passes per run Select the number of volume sweeps (passes of the piston) that are required for a full prove-run.

Prv start pump tmo

(Prover Start Pump Time-out)

‘SET’ a value for the maximum time that Status Output #8 should be active. This allows time for the Prover to respond to ‘Start Hydraulic Pump’ Status Output signal.

Prv stop pump tmo

(Prover Stop Pump Time-out)

‘SET’ a value for the maximum time that Status Output #9 should be active. This allows time for the Prover to respond to the ‘Stop Hydraulic Pump’ Status Output signal.

Prover Invar temp ‘SET’ a value for the Prover Invar temperature. This value is normally the ambient temperature of the environment.


Page 16A.42 7955 (CH16A/BC)

Table 16.26: Brooks Compact Prover (Sizes)

Brooks size Plenum Press. Constant ‘R’

Up-stream Multiplier

Flow tube ID (inches)

Wall thickness (inches)

8 inch 3.5 0.990590 8.250 0.6875

12 inch mini 3.2 0.991670 12.250 0.8750

12 inch std 3.2 0.991670 12.250 0.8750

18 inch 5.0 0.993010 17.500 1.250

24 inch 5.88 0.993464 25.500 1.0625

40 inch 4.45 0.985938 40.000 1.500

Other User-defined User-defined User-defined User-defined

Table 16.27: Brooks Compact Prover (Tube Material)

Tube material Modulus of Elasticity Per p.s.i.

Square coefficient of expansion per °F

304 st steel 28,000,000 0.0000177

17-4 st steel 28,500,000 0.0000120

Carbon steel 30,000,000 0.0000124

Other User-defined User-defined

(End of configuration task #3b)


7955 (CH16A/BC) Page 16A.43

16A.7.5 Configuration task #4a: Serial Port Communications (‘local’ prove) Objective: • Set-up for a combined ‘Metering’ and ‘Proving’ 7955 Flow Computer

What to do: Follow these instructions:

1. Navigate to this menu: <“Configure”>/<“Other parameters”>/<“Communications”>/<“MODBUS master”>/<”Slave devices”>


Table 16.28: Serial Port Communications (‘local’ prove)

Menu Data Instructions and Comments Slave device 1 func • Edit the option descriptor to be “FC PROVER”

Slv device 1 address • ‘SET’ the value to 0 (for ‘remote’ proving)

3. Navigate to the menu: <“Proving”>/<“Device to prove”>

4. Find the menu data page with this description: <“Proving device”>

5. Edit the option to be “Device 1”

(End of Configuration Task #4a)


Page 16A.44 7955 (CH16A/BC)

16A.7.6 Configuration task #4b: Serial Port Communications (‘remote’ prove) Objectives: The ‘Proving’ 7955 (performing proving functions) should be set-up as a ‘Master’ on a MODBUS network. Other devices, such as the ‘Metering’ 7955 ** (performing metering functions), must be set-up as ‘slaves’ on a MODBUS network. This organisation allows:

1. Metering data to be transmitted to the ‘Proving’ 7955 for use in proving calculations.

2. A new meter factor to be forwarded to the ‘Metering’ 7955.

3. The ‘Proving’ 7955 to ask the ‘Metering’ 7955 to control valves.

4. The ‘Metering’ 7955 to forward valve states to the ‘Proving’ 7955.

To avoid repetition, the following instructions are written with the assumption that the ‘Metering’ 7955 Flow Computer is being set-up as a slave with the MODBUS device address of 1.


(Steps 1 to 5 are for the ‘Proving’ 7955 Flow Computer)

1. Ensure that the serial port wired to the MODBUS network is configured to communicate with the ‘Metering’ Flow Computer on that network. Check settings for baud rate, character format, handshaking, signal standard and MODBUS specific parameters.

(Note: Refer to Chapter 7 of this manual for a full guide to 7955 Serial Communications).

2. Navigate to: <“Configure”>/<“Other parameters”>/<“Communications”>/<“MODBUS master”>


Table 16.29: Serial Port Communications (‘Proving 7955’)


Slave device 1 func Edit the option selected to be “FC PROVER”.

Slv device 1 port no Edit the option descriptor that corresponds to the serial port that is connected to the same MODBUS network as the ‘Metering’ Flow Computer.

Slv device 1 address ‘SET’ a value to be the same as the MODBUS address of the ‘Metering’ 7955.

4. Navigate to this menu: <“Proving”>/<“Device to prove”>

5. Change the option selected to be “Device 1”.

(Steps 6 to 9 are for the ‘Metering’ 7955 Flow Computer)

6. Ensure that the port wired to the network is configured to communicate with the ‘Proving’ 7955 Flow Computer on that network. Check settings for baud rate, character format, handshaking, signal standard, and MODBUS specific parameters.

7. Navigate to this menu: <“Configure”>/<“Other parameters”>/<“Communications”>/<“Ports”>

8. Select the sub-menu for the port that is wired to the network.


Table 16.30: Serial Port Communications (‘Metering 7955’)


Comms port owner Change the selection to “Modbus slave”.

P MODB slave add Set a value for the MODBUS base address of this ‘Metering’ Flow Computer.

P Modbus Features Change the selection to include “Alarm”. This allows the ‘Metering’ Flow Computer to inform the ‘Proving’ Flow Computer of new alarms.

** The 7955 Flow Computers must be running the same release of software version 2540.


7955 (CH16A/BC) Page 16A.45

16A.8 Operating a Prove Session This sub-section shows how a prove-session should be operated. The emphasis is placed on use of the 7955 front panel keyboard. However, it is possible to manipulate the various data locations from over a MODBUS network link.

Trouble-shooting sub-sections are included here to explain the cause of proving related alarms and session error messages.

Use this table to quickly locate the pages:

Section Purpose of Section 1st Page

16A.8.1 • Step-by-step instructions on operating a Bi-directional Proving Session. 16A.46

16A.8.2 • Step-by-step instructions on operating a Unidirectional Proving Session. 16A.50

16A.8.3 • Step-by-step instructions on operating a Brooks Compact Proving Session. 16A.53

Notice

Expressions of the form <“Configure”>/<“Prover”> translate into the following front panel keyboard sequences:




(4) Use the DOWN-ARROW key to scroll through several pages. Halt when the description “Prover” appears.


Note: Valves must be in the correct initial position prior to starting a prove session – all block valves must be closed and all divert valves must be closed. Failure to observe this results in a “Prover Abort Init i” alarm.


Page 16A.46 7955 (CH16A/BC)

16A.8.1 Operating a Bi-directional Proving Session


1. Review existing session settings and adjust if necessary:

Prover max runs Select the total number of prove-runs for a prove session – see page 16A.36.

Min good runs Select the number of consecutive good (passed) prove-runs required for a successful proving session – see page 16A.36.

Meter run Select a meter run to prove – this parameter is under the main menu <“Proving”> *

Device to prove Select the slave device number – as set-up on pages 16A.43/44.

Menu: <”Proving”>

Local ‘flowmeter’ proving:

Select “Device 1”.

Remote ‘flowmeter’ proving:

Select an option that corresponds to a MODBUS networked 7955 (slave device) that is providing metering-run information to the ‘proving’ 7955.

* Or <”Configure”>/<”Other Parameters”>/<”Communications”>/<”Modbus Master”>/<”Slave Device”>/<Device n>

2. Start a session

(2a) Navigate to this menu: <“Proving”>

(2b) Locate this menu data: <”Prover control”>

(2c) Change the option selected to be “Start”.

Note: A session can be aborted at any time by selecting the “Stop” option.

3. Monitor the progress of a prove-run

(3a) Navigate to this menu: <“Proving”>/<“Prover progress”>

(3b) Monitor the <“Prover progress”> menu data page for one full prove-run

Messages Instructions and Comments

Opening outlet valve Manual Control (Individual confirmation mode only): Open the Prover Outlet valve and then answer ‘yes’ to the on-screen prompt.

Manual Control (Group confirmation mode only): See “Valves aligned?” message prompt.

Automatic Control: No action required. The valve is commanded to be ‘fully’ open. The 7955 expects an ‘open’ valve state to be returned within a set time limit for this valve.

Opening inlet valve Manual Control (Individual confirmation mode only): Open the Prover Isolation (Inlet) valve and then answer ‘yes’ to the on-screen prompt.



Closing block valve Manual Control (Individual confirmation mode only): Close the Metering-run Block valve and then answer ‘yes’ to the on-screen prompt.

Manual Control (Group confirmation mode only): See “Valves aligned?” message prompt. Automatic Control: No action required. The valve is commanded to be fully closed. The 7955 expects an ‘close’ valve state to be returned within a set time limit for this valve.

Valves aligned? Yes No

Manual Control (Group confirmation mode only): Open the Prover Outlet valve, open the Prover Isolation (Inlet) valve, close the Metering-run Block valve and then answer “Yes” to the on-screen prompt. Answering “No” will abort the session.


7955 (CH16A/BC) Page 16A.47



Valves aligned No action required. Flow should be entering the Prover-loop.

Stabilisation. Stabilisation .. Stabilisation ...

Wait for the stabilisation period to end. The length of time for this was set during a configuration task.

Prover PreRun init No operator action required. This message is not usually seen.

Diverter valve fwd

Manual Control: Position the 4-way Diverter valve to the ‘forward’ position and then answer ‘yes’ to the on-screen prompt. Automatic Control: No action required. The 4-way Diverter valve is commanded to the ‘forward position. The 7955 expects a ‘forward’ valve state to be returned within a set time limit for this valve.

Note: Subsequent prove runs start with this message.

Ball release No operator action required. The ‘Proving’ 7955 automatically signals the Prover to launch the ‘displacer’. A set amount of time is allowed for the Prover to launch the ‘displacer’ and then the next message appears.

Ball launch No operator action required. The ‘displacer’ is now expected to be moving towards the ‘start’ detector.

Start sensor detect

No operator action required. The ‘Proving’ 7955 is now waiting for the Prover to send it a pulse to indicate that the ‘displacer’ has reached the ‘start’ detector. It is then known to be moving towards the ‘end’ detector. A set amount of time is allowed for this wait. The session is aborted if this time limit is reached without receiving a pulse. (See “Prover Abort” alarm description)

End sensor detect

No operator action required. Flowmeter pulses are now being counted by the ‘proving’ 7955. The ‘Proving’ 7955 is now waiting for the Prover to send a pulse to indicate that the ‘displacer’ has reached the ‘end’ detector. It is then known to be moving towards the launching mechanism. A set amount of time is allowed for this wait. The session is aborted if this time limit is reached without receiving a pulse.

Ball returning No operator action required. Flowmeter pulses have stopped being counted by the 7955. The ‘displacer’ is now moving to the launching mechanism. A set amount of time is allowed for this to be completed and then the next message appears.

Diverter valve rev

Manual Control: Position the 4-way Diverter valve to the ‘reverse’ position and then answer ‘yes’ to the on-screen prompt.

Automatic Control: No operator action required. The 4-way Diverter valve is commanded to the ‘reverse’ position. The 7955 expects a ‘reverse’ valve state to be returned within set time limit for ‘valve #4’. The next message appears when valve state is received.

Ball release No operator action required. The ‘Proving’ 7955 automatically signals the Prover to launch the ‘displacer’. A set amount of time is allowed for the Prover to launch the ‘displacer’ and then the next message appears.

Ball launch No operator action is required. The ‘displacer’ is now expected to be on way towards the ‘start’ detector.

Start sensor detect

No operator action is required. The ‘Proving’ 7955 is now waiting for the Prover to send it a pulse to indicate that the ‘displacer’ has reached the ‘start’ detector. It is then known to be moving towards the ‘end’ detector. A set amount of time is allowed for this wait. The session is aborted if this time limit is reached without receiving a pulse.

End sensor detect

No action required. Flowmeter pulses are now being counted by the 7955. The ‘Proving’ 7955 is now waiting for the Prover to send it a pulse to indicate that the ‘displacer’ has reached the ‘end’ detector. It is then known to be moving towards the launching mechanism. A set amount of time is allowed for this wait. The session is aborted if this time limit is reached without receiving a pulse.


Page 16A.48 7955 (CH16A/BC)



Ball returning No action required. Flowmeter pulses have stopped being counted by the 7955. The ‘displacer’ is now returning to the interchange mechanism. A set amount of time is allowed for this to be completed and then the next message appears.

Proving completed No operator action required. The prove-run is complete. Calculations now take place to produce a ‘Meter Factor’. Subsequent prove-runs start by re-positioning the 4-way Diverter valve. (Refer back to the “Diverter valve fwd” message)

4. Quickly navigate to the menu <“Proving”>/<“Prover current run”> to see the run number is now showing

a ‘1’ instead of a ‘0’. 5. Re-navigate to this menu: <“Proving”>/<“Prover progress”> and monitor the close of a session.


Proving session completed Press any key.

Press any key on the 7955 front panel keyboard. The next message will then appear.

New mf xxxxxx.xx Old mf xxxxxx.xx

Accept Disregard

This message will not appear if the minimum number of consecutive good prove-runs is not achieved or if a new ‘K factor’ is required instead of a new ‘Meter Factor’.

Press the blue ‘c’ key to accept the new ‘Meter Factor’ and allow it to be used in the next Corrected Volume flow rate calculation. The value is then written to the <“Meter factor”> menu data.

Press the blue ‘d’ key to NOT accept the new ‘Meter Factor’ and re-use the old ‘Meter Factor’.

Note: Modbus control of this prompt is done through the menu data: <”Prv store result”> It is located within this menu: <“Proving”>/<“Remote action”>.

New kf xxxxxx.xx Old kf xxxxxx.xx

Accept Disregard

This message will not appear if the minimum number of consecutive good prove-runs is not achieved or if a new ‘Meter factor’ is required instead of a ‘K factor’.

Press the blue ‘c’ key to accept the new ‘K factor’ and allow it to be used in the next Indicated Volume flow rate calculation. The value is then written to the <“Turb K factor”> menu data.

Press the blue ‘d’ key to NOT accept the new ‘K factor’ and re-use the old ‘K Factor’.


Prove print report Yes No

Press the blue ‘c’ key to transmit an ASCII report through the port that is configured for a direct connection to a printer.

Press the blue ‘d’ key to NOT print a report

Opening block valve Manual Control (Individual confirmation mode only): Open the Metering-run Block valve and then answer ‘yes’ to the on-screen prompt.



Closing inlet valve Manual Control (Individual confirmation mode only): Open the Prover Isolation (Inlet) valve and then answer ‘yes’ to the on-screen prompt.


Automatic Control: No action required. The valve is commanded to be ‘fully’ closed. The7955 expects a ‘closed’ valve state to be returned within a set time limit for this valve.


7955 (CH16A/BC) Page 16A.49



Closing outlet valve Manual Control (Individual confirmation mode only): Open the Prover Outlet valve and then answer ‘yes’ to the on-screen prompt.


Automatic Control: No action required. The valve is commanded to be ‘fully’ closed. The 7955 expects a ‘closed’ valve state to be returned within a set time limit for this valve.


Manual Control (Group confirmation mode only): Open the Metering-run Block valve, close the Prover Isolation (Inlet) valve, close the Prover Outlet valve and then answer “Yes” to the on-screen prompt. Answering “No” will abort the session.

Valves returned No action required. Flow should not be entering the Prover-loop.

End of prv session No action required. The normal Prover Report is transmitted through a serial port.

6. Navigate to the menu <“Proving”>/<“Last meter factor”> to see the new meter factor number.

7. Review information recorded from the session. (End of Bi-directional Proving Session)


Page 16A.50 7955 (CH16A/BC)

16A.8.2 Operating a Unidirectional Proving Session Follow these instructions:

1. Review existing session settings and adjust if necessary



Meter run Select a meter run to prove – this parameter is under main menu <“Proving”> *








2. Start a session


(2b) Locate this menu data page: <”Prover control”>


Note: A session can be aborted by selecting the “Stop” option. 3. Monitor the progress of a prove-run

(3a) Navigate to the menu: <“Proving”>/<“Prover progress”>



Opening outlet valve Manual Control (Individual confirmation mode only): Open the Prover Outlet valve and then answer ‘yes’ to the on-screen prompt.



Opening inlet valve Manual Control (Individual confirmation mode only): Open the Prover Isolation (Inlet) valve and then answer ‘yes’ to the on-screen prompt.





Automatic Control: No action required. The valve is commanded to be fully closed. The 7955 expects an ‘close’ valve state to be returned within a set time limit for this valve.




7955 (CH16A/BC) Page 16A.51



Valves aligned No action required. Flow should be entering the Prover-loop.

Stabilisation. Stabilisation .. Stabilisation ...

Wait for the stabilisation period to end. The length of time for this was set during a configuration task.


Start prove run No operator action required. The ‘Proving’ 7955 automatically signals the Prover to launch the ‘displacer’. A set amount of time is allowed for the Prover to launch the ‘displacer’ and then the next message appears.

Ball launch No operator action required. The ‘displacer’ is now expected to be moving towards the ‘start’ detector.

Start sensor detect No operator action required. The ‘Proving’ 7955 is now waiting for the Prover to send it a pulse to indicate that the ‘displacer’ has reached the ‘start’ detector. It is then known to be moving towards the ‘end’ detector. A set amount of time is allowed for this wait. The session is aborted if this time limit is reached without receiving a pulse.

End sensor detect No operator action required. Flowmeter pulses are now being counted by the ‘proving’ 7955. The ‘Proving’ 7955 is now waiting for the Prover to send a pulse to indicate that the ‘displacer’ has reached the ‘end’ detector. It is then known to be moving towards the launching mechanism. A set amount of time is allowed for this wait. The session is aborted if this time limit is reached without receiving a pulse.

Ball returning No operator action required. Flowmeter pulses have stopped being counted by the 7955. The ‘displacer’ is now moving to the launching mechanism. A set amount of time is allowed for this to be completed and then the next message appears.

Proving finished No operator action required. The prove-run is complete. Calculations now take place to produce a new ‘Meter Factor’. Subsequent prove-runs are started by launching the ‘displacer’.

4. Select the menu <“Proving”>/<“Prover current run”> to see the run number is showing a ‘1’ instead of a ‘0’ 5. Re-navigate to this menu: <“Proving”>/<“Prover progress”> and monitor the close of a session





Accept Disregard


Press the blue ‘c’ key to accept the new ‘Meter Factor’ and allow it to be used in the next Corrected Volume flow rate calculation. The value is then written to the <“Meter factor”> menu data.

Press the blue ‘d’ key to NOT accept the new ‘Meter Factor’ and re-use the old ‘Meter Factor’.



Accept Disregard

This message will not appear if the minimum number of consecutive good prove- runs is not achieved or if a new ‘Meter factor’ is required instead of a new ‘K factor’.

Press the blue ‘c’ key to accept the new ‘K factor’ and allow it to be used in the next Indicated Volume flow rate calculation. The value is then written to the <“Turb K factor”> menu data.

Press the blue ‘d’ key to NOT accept the new ‘K factor’ and re-use the old ‘K Factor’.

Note: Modbus control of this prompt is done through the menu data: <”Prv store result”>


Page 16A.52 7955 (CH16A/BC)











Automatic Control: No action required. The valve is commanded to be ‘fully’ closed. The7955 expects a ‘closed’ valve state to be returned within a set time limit for this valve.







End of prv session No action required. The normal Prover Report is transmitted through a serial port.

6. Navigate to the menu <“Proving”>/<“Last meter factor”> to see the new meter factor number

7. Review information recorded from the session (End of Unidirectional Proving Session)


7955 (CH16A/BC) Page 16A.53

16A.8.3 Operating a Brooks Compact Proving Session Follow these instructions:




Meter run Select a meter run to prove – this parameter is under main menu <“Proving”> *








2. Start a session


(2b) Locate this menu data page: <”Prover control”>


Note: A session can be aborted by selecting the “Stop” option. 3. Monitor the progress of a prove-run

(3a) Navigate to the menu: <“Proving”>/<“Prover progress”>



Start hydraulic pump No operator action required. The ‘Proving’ 7955 automatically signals the Prover to start retracting the ‘displacer’ to the standby position. A set amount of time is allowed for the Prover to do this before the next message appears.

Upstream status

No operator action. A set amount of time, <”Prv inter-run delay”>, is allowed for the Prover to signal that the ‘displacer’ (piston) is in the standby position. The session is aborted when this time limit is reached and the Prover has not signalled the 7955.

Opening outlet valve

Manual Control (Individual confirmation mode only): Open the Prover Outlet valve and then answer ‘yes’ to the prompt.


Automatic Control: No action required. Valve is commanded to be fully open. 7955 expects an ‘open’ valve state to be returned within a set time limit for this valve.

Opening inlet valve

Manual Control (Individual confirmation mode only): Open the Prover Isolation (Inlet) valve and then answer ‘yes’ to the on-screen prompt.




Page 16A.54 7955 (CH16A/BC)


Messages Instructions and Comments Notes



Automatic Control: No action required. The valve is commanded to be fully closed. The 7955 expects an ‘close’ valve state to be returned within a set time limit for this valve.



Valves aligned No operator action required. Flow should now be entering the Prover-loop.

Stabilisation. Stabilisation.. Stabilisation...

No operator action required. Plenum pressure is at the required level. Now wait for the stabilisation period to end. The length of time for this was set during a configuration task.

Plenum pressure. Plenum pressure.. Plenum pressure... Plenum pressure....

No operator action required. Wait for Plenum pressure to reach the required level. The length of time for this was set during a configuration task. Failure to get the Prover to achieve the required level results in the session being aborted.


Start prove run No operator action required. The ‘Proving’ 7955 automatically signals the Prover to launch the ‘displacer’. A set amount of time is allowed for the Prover to launch the ‘displacer’ and then the next message appears.

Piston launch No operator action required. The ‘displacer’ (piston) is now expected to be moving towards the ‘start’ detector.

Start sensor detect

No operator action required. The ‘Proving’ 7955 is now waiting for the Prover to send it a pulse to indicate that the ‘displacer’ has reached the ‘start’ detector. It is then known to be moving towards the ‘end’ detector. A set amount of time is allowed for this wait. The session is aborted if this time limit is reached without receiving a pulse.

End sensor detect

No operator action required. Flowmeter pulses are now being counted by the ‘proving’ 7955. The ‘Proving’ 7955 is now waiting for the Prover to send a pulse to indicate that the ‘displacer’ has reached the ‘end’ detector. A set amount of time is allowed for this wait. The session is aborted if this time limit is reached without receiving a pulse.

Piston returning

No operator action required. Flowmeter pulses have stopped being counted by the 7955. The ‘displacer’ (piston) is now returning to the up-stream position. A set amount of time is allowed for this to be completed and then the next message appears.

Stop hydraulic pump No operator action required. The ‘Proving’ 7955 automatically signals the Prover to stop moving the ‘displacer’. A set amount of time is allowed for the Prover to do this before the next message appears.

Proving finished No operator action required. The prove-run is complete. Calculations now take place to produce a new ‘Meter Factor’. Subsequent prove-runs are started by the 7955 re-launching the ‘displacer’.

4. Select the menu <“Proving”>/<“Prover current run”> to see the run number is showing a ‘1’ instead of a ‘0’.

5. Re-navigate to this menu: <“Proving”>/<“Prover progress”> and monitor the close of a session.


Proving session Completed Press any key.



7955 (CH16A/BC) Page 16A.55




Accept Disregard


Press the blue ‘c’ key to accept the new ‘Meter Factor’ and allow it to be used in the next Corrected Volume flow rate calculation. The value is then written to the <“Meter factor”> menu data of the ‘Metering 7955’ or the ‘Metering/Proving 7955’.

Press the blue ‘d’ key to NOT accept the new ‘Meter Factor’ and re-use the existing ‘Meter Factor’.



Accept Disregard

This message will not appear if the minimum number of consecutive good prove-runs is not achieved or if a new ‘Meter factor’ is required instead of a new ‘K factor’.

Press the blue ‘c’ key to accept the new ‘K factor’ and allow it to be used in the next Indicated Volume flow rate calculation. The value is then written to the <“Turb K factor”> menu data of the ‘Metering 7955’ or the ‘Metering/Proving 7955’.

Press the blue ‘d’ key to NOT accept the new ‘K factor’ and re-use the existing ‘K Factor’.

Note: Modbus control of this prompt is done through the menu data: <”Prv store result”>
















End of prv session No action required. The Brooks Prover Report is transmitted through a serial port.

6. Navigate to the menu <“Proving”>/<“Last meter factor”> to see the new meter factor number

7. Review information recorded from the session

(End of Brooks Compact Proving Session)


Page 16A.56 7955 (CH16A/BC)

16A.9 Archiving of Proving Information The 7955 Flow Computer is permanently configured to record proving information in a tamper-proof archive. Information (data values) from an entire session, including all prove-passes and prove-runs, is stored in the Prover Archive. The capacity of this archive is 1 session. A complete set of values from any prove-pass†† and any prove-run of the session can be displayed for viewing or for retrieval by an external Modbus networked device, but can not be printed out through a serial port. Editing of an archived value is not possible. Each attempt to edit a displayed value (from the archive) will see an “*** Access denied ***” message. Although the Prove Archive is a fixed size and operates independently of all other data archiving activities, it is worth reading about other Archiving facilities. (See Chapter 9) The Prover Archive display is located within this menu: <“Proving”>/<“Prover log”>.

16A.9.1 Archived Session Menu Data

Menu Data * What is this data?

Prv session status Final status of the proving session

Prv new meter factor Generated ‘Meter factor’

Prove start time Date and time that the session commenced

Prv duration Total amount of time for the entire session

Prv MF deviation ‘Meter factor’ deviation value for the session. The lowest deviation is 0.00

Prv old meter factor The existing/previous ‘Meter factor’ from the ‘Metering 7955’

Prover new K factor Generated ‘K factor’

Prv old K factor The existing/previous ‘K factor’ from the ‘Metering 7955’

Prv interp pulses The interpolated pulse count from all good prove-runs

Prv ave meter temp The average fluid temperature (at the flow point) from all the good prove-runs

Prv ave meter press The average pressure (at the flow metering point) from all the good prove-runs

Prv ave flow rate Averaged rate of flow in the prover-loop – from all good prove-runs

Prv meter freq Prover pulse frequency – from all good prove-runs

Prv ave base dens Average fluid density value (at base conditions) from all good prove-runs

Prover CTS The temperature correction factor for the steel pipe-work of the Prover

Prover CPS The pressure correction factor for the steel pipe-work of the Prover

Prover CTLp Correction factor for the effect of temperature on the fluid in the Prover-loop

Prover CPLp Correction factor for the effect of pressure on the fluid in the Prover-loop

Prover CTLm Correction factor for temperature effect on fluid flowing through the meter under test

Prover CPLm Correction factor for pressure effect on the fluid flowing through the meter under test

Prover corr volume The Prover base volume that has been corrected for temperature and pressure effects on the liquid and the steel

Prv metered volume This volume given by dividing <”Prv interp pulses”> with <”Prv old K factor”>

Prv corr metered vol The metered volume corrected for temperature and pressure effects on the fluid flowing through the meter under test.

Prv MF deviation The difference between the new ‘Meter factor’ and the old ‘Meter factor’.

* Abbreviations: “Prv” = Prover, “interp” = interpolated, “temp” = temperature, “freq” = frequency, “ave” = average

“press” = pressure, “dens” = density, “corr” = corrected, “MF” = Meter factor, “vol” = volume

†† Applicable only when using a Brooks Compact Prover. A full prove-run consists of one or more passes (volume sweeps).


7955 (CH16A/BC) Page 16A.57

16A.9.2 Archived Prove-run Menu Data (Use the <”View prove run data”> parameter to choose another prove-run: 0 = last run, 1 = 1st run, etc.)


Prv run status This shows the final status of the prove-run

Prv run prv temp Average of Prover Inlet and Outlet temperature measurements taken during the run

Prv run prv press Average of Prover Inlet and Outlet pressure measurements taken during the run

Prv run stream temp Average of all the temperature measurements during the prove-run

Prv run stream press Average of all the pressure measurements during the prove-run

Prv run strm volrate Average of all Indicated Volume flow rate values during the prove-run

Prv run freq The count of interpolated pulses received from the flowmeter during the prove-run.

Prv run meter fact A ‘Meter factor’ value. Calculated using values generated from the prove-run.

Prv run pulse count Uncorrected pulse count for the prove-run

Prv run corr pulse Corrected (interpolated) pulse count for the prove-run

Prv run TDVOL This is the time between the piston reaching the ‘start’ detector and the piston reaching the ‘end’ detector. (See page 16A.10 for details)

Prv run TDFMP This is the timing for correcting a pulse count from a volume sweep. Turn to page 16A.10 for details

Prv run base temp The ‘SET’ base temperature at the beginning of the prove-run.

* Abbreviations: “Prv” = Prover, “interp” = interpolated, “temp” = temperature, “freq” = frequency, “press” = pressure,

“dens” = density, “corr” = corrected, “MF” = Meter factor, “volrate” = volume flow rate,

“strm” = stream, “fact” = factor

16A.9.3 Archived Brooks Compact Prove-pass Menu Data (Use <”View prove pass data”> to choose another volume sweep: 0=last pass, 1=1st, 2=2nd, etc.)

Menu Data What is this data?

Prv pass pulse count The uncorrected pulse count for a single pass of the presently selected prove-run

Prv pass corr pulse The interpolated pulse count for a single pass of the presently selected prove-run

Prv pass TDVOL This is the time between the piston reaching the ‘start’ detector and the piston reaching the ‘end’ detector. (See 16A.10 for details)

Prv pass TDFMP This is the timing for correcting a pulse count from a volume sweep. Turn to page 16A.10 for details.

Prv pass flow rate The Indicated Volume flow rate value at the start of a prove-pass.

* Abbreviations: “Prv” = Prover, “corr” = corrected


Page 16A.58 7955 (CH16A/BC)

16A.10 Prover Reporting The ‘Proving’ 7955 offers to print-out a proving report at the end of a prover session. Alternatively, it can be printed at any time by a making an appropriate selection from within the PRINTER (soft-key) menu. This section shows a sample of each proving report.

16A.10.1 Print Requests using the front panel keyboard

(Ensure that one serial port is configured for the connection to a printer)


1. Press the grey PRINT-MENU soft-key

2. Navigate to this menu: <“Print report”>/<“Print”>

3. Press the ‘b’ soft-key

4. Use the UP-ARROW key to scroll through the list of reports

5. Press the ENTER key when “Prover report” appears on line two.



7955 (CH16A/BC) Page 16A.59

16A.10.2 Prove Summary Report (All Provers) Prove Summary Report -------------------- Prove report number: 8 Site location: Emerson Start time: 17/06/1999 11:58:10 Duration: 183.000 s Prover Details -------------- Prover type Uni-directional Base volume 1.000000 m3 @ cal temp 20.000000 Deg.C Internal dia 0.300 m, wall thickness 0.006 m Prover tube material 304 st steel, Modulus of E 193053196000.000 N/M2 Prv expansion coeff 0.00000000 PPM/Deg.C Meter Details ------------- Meter serial number: 991234 Meter number FT-1001 Old K factor 3600.000000 pulse/m3, old meter factor 0.999945 Count deviation 2.229 %, MF deviation 2.233 % Run Data -------- Run Interp -Temperature- --Pressure--- Flow Rate Base Dens Meter Meter Sts pulses Prover Meter Prover Meter freq factor --- Deg.C--- ---bar abs--- m3/hour kg/m3 Hz 1 3629.318 50.817 50.812 30.477 30.497 95.435 923.94694 95.435 0.9919 OK 2 3559.853 50.829 50.809 30.485 30.487 95.432 923.94964 95.432 1.0112 OK 3 3549.296 50.768 50.809 30.471 30.480 95.433 923.95164 95.433 1.0143 OK -------------------------------------------------------------------------------- Avg:3579.489 50.805 50.810 30.478 30.488 95.433 923.94941 95.433 Prover Data ----------- (1) Base volume of prover 1.000000 m3 (2) Ctsp: Correction for temperature on steel 1.00000 (3) Cpsp: Correction for pressure on steel 1.00000 (4) Ctlp: Correction for temperature on liquid 0.97406 (5) Cplp: Correction for pressure on liquid 1.00210 (6) Corrected prover volume (1 * 2 * 3 * 4 * 5) 0.976109 m3 Meter Data ---------- (7) Metered volume (avg. pulse / previous K factor) 0.994303 m3 (8) Ctlm: Correction for temperature on liquid 0.97406 (9) Cplm: Correction for pressure on liquid 1.00210 (10) Corrected meter volume (7 * 8 * 9) 0.970545 m3 Meter Factor ------------ (11) New meter factor (6 / 10) 1.00573 (12) New K factor (previous K factor / 11) 3579.47804 (13) Meter factor deviation from previous 0.579 % Remarks: ________________________________________________________________________ ________________________________________________________________________ Signature: Date: Company: ____________________ ______________ _____________________ Signature: Date: Company: ____________________ ______________ _____________________ ********************************* END OF REPORT ********************************


Page 16A.60 7955 (CH16A/BC)

16A.11 Trouble-shooting Guide This section provides reference information for finding out why a prove-run and/or prove-session was not successful. The principal 7955 areas to examine are the alarm log messages and the status error messages.

16A.11.1 Prove Session Alarms Session related alarms can be seen in the History Alarm Log.

Base Alarm Message What caused this alarm to appear?

Prover Abort

(Prove session aborted) A reason is indicated by the additional letter after the “Prover Abort” message: ‘V’ = Valve alignment failed or Prover is not ready ; ‘i’ = Valves not in correct initial position or communications not set-up correctly for

local/remote proving or no flow in run being proved (check flow status location). ‘I’ = Pre-prove run (Complete configuration tasks) ‘L’ = Leakage detected ‘c’ = All prove runs completed ‘S’ = Incomplete metering-run configuration ‘s’ = Conditions not stable ‘p’ = Plenum pressure target not achieved.

Prover limit

A reason is indicated by the additional letter after the “Prover limit” message: ‘F’ = Flow rate difference between Meter-run and Prover ‘T’ = Temperature difference between Meter-run and Prover ‘P’ = Pressure difference between Meter-run and Prover ‘M’ = Meter factor difference between Meter-run and Prover ‘E’ = Error pulses detected ‘R’ = Brooks Compact Prover is not signalling that it is ready for proving. ‘a’ = Prover Archive too small – software fault occurred

Prover timeout A reason is indicated by the additional letter after the “Prover timeout” message: ‘S’ = ‘Displacer’ did not reach the ‘start’ detector within a set time limit ‘E’ = ‘Displacer’ did not reach the ‘end’ detector within a set time limit

Valve failed

A ‘fail’ valve state was received by the 7955. The additional character identifies the valve: ‘1’ = Valve one (Prover Isolation valve), ‘2’ = Valve two (Prover Outlet valve) ‘3’ = Valve three (Metering-run Block valve), ‘4’ = Valve four (4-way diverter valve)

Valve timeout

Valve has not responded within a set time limit. The additional character identifies the valve: ‘1’ = Valve one (Prover Isolation valve), ‘2’ = Valve two (Prover Outlet valve) ‘3’ = Valve three (Metering-run Block valve), ‘4’ = Valve four (4-way diverter valve)

16A.11.2 Session Error Messages

Status messages can be seen in the <“Proving”>/<“Prover progress”> menu.

Message What caused this message to appear?

Inlet valve failed

Outlet valve failed

Block valve failed

Diverter valve fail

(1) Valve state indicates that it has suffered a failure or (2) Valve did not respond within a set time limit.

Start sensor timeout Start pulse not received from first detector switch within set time limit.

End sensor timeout End pulse not received from final detector switch within set time limit.

Prover error pulses Turbine error pulses detected during pulse count.

Prove aborted See Alarm “Prover Abort”


7955 (CH16A/BC) Page 16A.61

16A.12 Miscellaneous Reference Information

16A.12.1 Proving sequence flowcharts and timing diagrams

Abort state

Abort state

No Yes

(Increase"Prover run number")

No

Yes

Abort state or"Prover run timeout" = 0

Abort state or"Prover start timeout" = 0

Stabilsationcompleted

Prover control = "Start"

Valves aligned

Abort state or"Prv stable timeout" = 0

Manual valve control(Valve duration = 0) Automatic valve control

(Valve duration > 0)

Prover controlis "idle"

INITIALISE

ALIGN VALVES

STABILISE

Abort state orValve failed state

RETURN VALVES

START

RUN

STOP

Calculate a newmeter factor

Max provesor

Finished session

Automaticvalve

control

Start pulse detected

End pulse detected

Unidirectional Proving Sequence


Page 16A.62 7955 (CH16A/BC)

End pulse detected


End pulse detected


Abort state

No Yes

(Increase"Prover run number")

No

Yes


Abort state or"Prover start timeout" = 0

Stabilsationcompleted

Prover control = "Start"

Valves aligned

Abort state or"Prv stable timeout" = 0

Manual valve control(Valve duration = 0) Automatic valve control

(Valve duration > 0)

Prover controlis "idle"

INITIALISE

ALIGN VALVES

STABILISE

Abort state orValve failed state

RETURN VALVES

ROTATE 4-WAYDIVERTER (forward)

PROVE RUN

Calculate a newmeter factor

Max provesor

Finished session

Automaticvalve

control

STOP

ROTATE 4-WAYDIVERTER (reverse)

PROVE RUN (return)

STOP


Bi-directional Proving Sequence


7955 (CH16A/BC) Page 16A.63

16A.12.2 Uni/Bi-directional Prover Timing Diagram The following timing diagram describes a normal Unidirectional (or Bi-directional proving) session operation.

Stabilise

Start Delay

Start Timeout

Run Timeout

End Delay

Inter-Run Delay

Repeat for each Prover Run

Start

Proving

Status Outputs

Timing Parameters

(Start Sensor Timeout)

(End Sensor Timeout)

‘Start timeout’ & ‘run timeout’ indicate a sensor detect or timeout.


Page 16A.64 7955 (CH16A/BC)

16A.12.3 Brooks Compact Prover Timing Diagram The following timing diagram describes a normal Brooks Compact proving session operation.

Status Outputs

Timing parameters

Start Hydraulic Pump

Stop Hydraulic Pump

Upstream status

Run command

Plenum press charge

Plenum press vent

Status Inputs

Valves alignment

Stabilise

Plenum pressure

Inter-Run delay/Upstream status tmo

Start delay

Start timeout

Run timeout

End delay

Inter-Run delay/upstream tmo

Start detect

End detect

Prover ready

Pre condition Prover run Prover run End of prv session

Start hydraulic pump

Stop hydraulic pump

Chapter 16(b) Master Meter Proving

7955 2540 (Ch16b/BB) Page 16b.1

16B. Master Meter Proving

16B.1 What is the purpose if this Chapter? This chapter has been written to provide a guide to the 7955 Flow Computer software and hardware support for master meter proving.

To use this guide effectively, it is essential to be familiar with the general proving support (Chapter 16A), and be familiar with the 7955 Flow Computer keys (Chapter 5) and the menu system (Chapter 6).

The data necessary for configuring a measurement/feature can be found in separate parts of the menu structure. A notation has therefore been used as a short method of explaining how to move from the present menu to another menu.


Step 1: Press the MAIN-MENU key Step 2: Use the DOWN-ARROW (‘V’) key to scroll through pages until the word “Configure” is seen. Step 3: Press the blue (letter) key that is alongside the word “Configure”. Step 4: Use the DOWN-ARROW key to scroll through pages until the “Flow rate” is seen. Step 5: Press the blue (letter) key that is alongside the “Flow rate” descriptor.

Sometimes, it is more convenient to use the MAIN-MENU key (especially if lost). However, use of the BACK-ARROW key is a much more common method of returning to a previous menu level. Note: The menu structure will vary in other software versions and releases.

16B.2 Master meter proving (with a 7955 multiple-run flow computer) • Read the overview that starts on this page • Understand the input and outputs that are listed in Section 16B.4 • Review the configuration details in Section 16B.5 • Review the operating instructions in Section 16B.6 Overview Master Meter Proving is intended to allow in-situ proving of a turbine/PD or Coriolis flow meter against an infrequently used, high integrity (so-called master) meter. You can select any one of 16 volumetric/mass meters to be tested - proved – individually against the ‘master’ meter.

Various combinations of methods are supported:

• Volumetric master meter proving a turbine meter for volume • Volumetric master meter proving a mass coriolis meter for mass • Coriolis mass master meter proving a mass coriolis meter for mass • Coriolis mass master meter proving a turbine meter for volume.

The main principle is that the meter-under-test and the ‘master’ meter are directly compared in terms of flow over a criteria-controlled period. Criteria for ending a comparison can be either attaining a pre-set number of pulses or a pre-set volume of flow. Differences from the comparison form the basis for generating a new flow correction factor. MF (Meter factor) calculations are shown in on page 16b.3.

In common with pipe proving support, valve alignments, stabilisation checking, and flow factor validations all feature in master meter proving. (Also, see page 16B.6 for a tour of a typical proving session) Local and Remote Proving Support Local and remote proving of meters is supported. With five pulse inputs available on a 7955, it can be connected to: 4 x local metering-runs (streams) or 3 x local metering-runs (streams) with one input for ‘remote’ metering-runs. Pulse input 5 is reserved for the master meter.

A ‘local’ meter-run connection involves direct – point-to-point – wiring to field instrumentation (sensors, valve controllers and flowmeter) of a single meter-run (run).

A ‘remote’ meter-run connection involves MODBUS networked flow computers from the 7955 Flow Computer. These ‘remote’ flow computers require direct – ‘local’ meter-run – connections to field instrumentation. Additionally, pulses from those ‘local’ meter-run meters must also be directed, by some external switching circuitry, into Pulse Input 5 of the ‘proving’ 7955.


Page 16b.2 7955 2540 (Ch16b/BB)

Proving Control Proving related functions are largely controlled by a single 7955 Flow Computer. Proving sessions are operated from the front panel of the 7955 or by MODBUS communications between the 7955 and a host. Valve Support Valve control and monitoring support is optional and is as described in the valves section of Chapter 16(A). Master meter proving involves metering-run block valves (see “HSO/C 1821” in Figure 16.1) and prover inlet valves 1 (see “HSO/C 1831”). A general configuration is shown in Figure 16.1. All the required 7955 Flow Computer connections are as guided in Section 16B.4 of this addendum.

Figure 16.1: General Metering Configuration

Turbine 1

Turbine 2

Master Turbine

Inlet

Inlet

HSO/C 1821

HSO/C 1831

Outlet

HSO/C 1851

HSO/C 1841

HSO/C 1861

1 Where there is also prover outlet valve, it is necessary to control the prover outlet valve and the prover inlet valve with the same

pair of status outputs. Monitor state outputs from either the prover inlet valve or the prover outlet valve.


7955 2540 (Ch16b/BB) Page 16b.3

16B.3 Master Meter Proving Calculations The Master Meter Proving calculations for each scenario are listed here for your convenience. To avoid duplication of information, it is also necessary to refer to the calculation section in Chapter 16A. Unless otherwise stated, calculation terms here are annotated with parameters as displayed within the Prover Archive (Master Meter) prove-run menus.

16B.3.1 Volumetric Master Meter Proving of a Volumetric Meter (for volume) MMP#1: Corrected Meter-under-test Volume

Using: mutCV = CplmCtlmmutKf

NC

V** * Parameter value copied from ‘Metering’ 7955

Where:

CVmut = Corrected Meter-under-test Volume….…………...{Menu Data: <”Prv run CorMeterVol”>}

NC = Interpolated count of pulses (Meter-under-test)……..….....……{See Calculation MMP#3}

Ctlm = Correction factor for effect of temperature on fluid at the Meter-under-test……….……… …………………………………………………..…………….{Menu Data: <”Prv run CTLm”>}

Cplm = Correction factor for effect of pressure on fluid at the Meter-under-test…………..………. …………………………………………………..…………….{Menu Data: <”Prv run CPLm”>}

KfVmut = Current ‘K factor’ for Meter-under-test (in volumetric units)………..……………..………..... …………………………………………………….………..{Menu Data: <”Prv run MUT K F”>} *

Calculation Note: Refer to Chapter 16(A) calculations for further information on the CTL and CPL factors

MMP#2: Corrected ‘Master Meter’ Prover Volume

Using: mmCV = ( ) ( )CpspCtspCplpCtlpMFmmKf

PCmm

V*****

Where:

CVmm = Corrected ‘Master Meter’ Prover Volume…….…………{Menu Data: <”Prv run corr vol”>}

PC = Pulse count (Master Meter)……………………….…{Menu Data: <”Prv run pulse count”>}

MFmm = Existing ‘Meter Factor’ for Master Meter……..……{Menu Data: <”Prv run MM MFactor”>}

Ctlp = Correction factor for effect of temperature on fluid at the Master Meter…………………… …………………………………………………..…..………….{Menu Data: <”Prv run CTLp”>}

Cplp = Correction factor for effect of pressure on fluid at the Master Meter……………………….. …………………………………………………..…..………….{Menu Data: <”Prv run CPLp”>}

Ctsp = Correction factor for effect of temperature on the Master Meter…………………….……… ………………………………...………………..…..………….{Menu Data: <”Prv run CTSp”>}

Cpsp = Correction factor for effect of pressure on the Master Meter………………………………… ……………………………..……………………….………….{Menu Data: <”Prv run CPSp”>}

KfVmm = Current ‘K factor’ for Master Meter (in volume units)………..…………………………………

………………………………………………………... {Menu Data: <”Prv run MM K Factor”>}

Calculation Note: Refer to Chapter 16(A) calculations for further information on the CTL and CTS factors


Page 16b.4 7955 2540 (Ch16b/BB)

MMP#3: Interpolated Pulse Count

Using: NC = mut

mutmm t

Pulsest *

Where:

NC = Interpolated count of pulses (Master Meter)………. {Menu Data: <”Prv run corr pulse”>}

tmm = Time to collect Master Meter pulses………..…….... {No Menu Data}

tmut = Time to collect pulses from the Meter-under-test…. {No Menu Data}

MMP#4: New ‘Meter-under-test’ Meter Factor

Using: MFNEW = mutmm

CVCV

……………………………………..…….…… {Menu Data: <”Prv run meter factor”>}


7955 2540 (Ch16b/BB) Page 16b.5

16B.3.2 Volumetric Master Meter Proving of a Coriolis Mass Meter (for Mass) MMP#5: Indicated ‘Meter-under-test’ Mass

Using: mutIM = mutKf

NCM

* Parameter value copied from ‘Metering’ 7955

Where:

IMmut = Indicated Mass (Meter-under-test)………………{Menu Data: <”Prv run SUT ind mass”>}


KfMmut = Current ‘K factor’ for Meter-under-test (in pulse/mass or mass/pulse units) ………………

…………………………………………………….………..{Menu Data: <”Prv run MUT K F”>} *

MMP#6: Corrected ‘Master Meter’ Prover Mass

Using: mmCM = PmmM

CpspCtspMFmmKf

PC ρ****

Where:

PC = Pulse count (Master Meter) ……………………...…{Menu Data: <”Prv run pulse count”>}

MFmm = Existing ‘Meter Factor’ of the Master Meter………{Menu Data: <”Prv run MM MFactor”>}

Ctsp = Correction factor for effect of temperature on the Master Meter……………………………. ………………………………...……………….…..………….{Menu Data: <”Prv run CTSp”>}

Cpsp = Correction factor for effect of pressure on the Master Meter…………………...…………… ………………………………...………..……..…..………….{Menu Data: <”Prv run CPSp”>}

KfMmm = Current ‘K factor’ of Master Meter (in pulse/mass or mass/pulse units) ……….…..……… ……………………………………………..………... {Menu Data: <”Prv run MM K Factor”>}

ρP = Master Meter fluid density……………...…………………………{See Calculation MMP#7}

Calculation Note: Refer to Chapter 16(A) calculations for further information on the CTL and CTS factors MMP#7: Master Meter fluid density Using: ρP = BCplpCtlp ρ** Where:

Ctlp = Correction factor for effect of temperature on fluid at the Master Meter………………..….

………………………………...……………….…..………….{Menu Data: <”Prv run CTLp”>}

Cplp = Correction factor for effect of pressure on fluid at the Master Meter……………………….


ρP = Base density………………………………………………….{Menu Data: <”Base Density”>}

Calculation Note: Refer to Chapter 16(A) calculations for further information on the CTL and CTS factors MM#8: New ‘Meter-under-test’ Meter Factor

Note: The product mass does not change with the effects of temperature and pressure. Hence, Indicated Mass (IM) is used when deriving the Meter Factor (MF) for the meter-under-test.


IMCM

…………………………….………………..{Menu Data: <”Prv run meter factor”>}


Page 16b.6 7955 2540 (Ch16b/BB)

16B.3.3 Coriolis Mass Master Meter Proving a Coriolis Mass Meter (by Mass)

MMP#9: Indicated ‘Meter-under-test’ Mass

Using: mutIM = mutKf

NCM

* Parameter value copied from ‘Metering’ 7955

Where:

IMmut = Indicated Mass (Meter-under-test)………………{Menu Data: <”Prv run SUT ind mass”>}


KfMmut = Current ‘K factor’ for Meter-under-test (in pulse/mass or mass/pulse units) ………………

…………………………………………………….………..{Menu Data: <”Prv run MUT K F”>} *

MMP#10: Corrected ‘Master Meter’ Prover Mass

Using: mmCM = CpspCtspMFmmKf

PCmm

M***

Where:



Ctsp = Correction factor for effect of temperature on the Master Meter……………………………. ………………………………...……………….…..………….{Menu Data: <”Prv run CTSp”>}

Cpsp = Correction factor for effect of pressure on the Master Meter…………………...…………… …………………………….…..………..……..…..………….{Menu Data: <”Prv run CPSp”>}

KfMmm = Existing ‘K factor’ of Master Meter (in pulse/mass or mass/pulse units) …………..……… ……………………………………………..…...….... {Menu Data: <”Prv run MM K Factor”>}

MMP#11: New ‘Meter-under-test’ Meter Factor

Note: The product mass does not change with the effects of temperature and pressure. Hence, Indicated Mass (IM) is used when deriving the Meter Factor (MF) for the meter-under-test.


IMCM

…………………………………………..…..{Menu Data: <”Prv run meter factor”>}


7955 2540 (Ch16b/BB) Page 16b.7

16B.3.4 Coriolis Mass Master Meter Proving a Volumetric Meter (by Volume)

MMP#12: Corrected Meter-under-test Volume

Using: mutCV = CplmCtlmmutKf

NC

V** * Parameter value copied from ‘Metering’ 7955

Where:

CVmut = Corrected Meter-under-test Volume….…………...{Menu Data: <”Prv run CorMeterVol”>}


Ctlm = Correction factor for effect of temperature on fluid at the Meter-under-test……….……… …………………………………………………..…………….{Menu Data: <”Prv run CTLm”>}

Cplm = Correction factor for effect of pressure on fluid at the Meter-under-test…………..………. …………………………………………………..…………….{Menu Data: <”Prv run CPLm”>}

KfVmut = Current ‘K factor’ for Meter-under-test (in volumetric units)……………………..………..... …………………………………………………….………..{Menu Data: <”Prv run MUT K F”>} *

Calculation Note: Refer to Chapter 16(A) calculations for further information on the CTL and CPL factors

MM#13: Corrected ‘Master Meter’ Prover Volume

Using: mmCV =( )

Pmm

M

CpspCtspMFmmKf

PCρ*

**

Where:



Ctsp = Correction factor for effect of temperature on the Master Meter…………………….……… ………………………………...………………..…..………….{Menu Data: <”Prv run CTSp”>}

Cpsp = Correction factor for effect of pressure on the Master Meter………………………………… ……………………………..……………………….………….{Menu Data: <”Prv run CPSp”>}

ρP = Master Meter fluid density…………………………………………{See Calculation MMP#7}

Calculation Note: Refer to Chapter 16(A) calculations for further information on the CTL and CTS factors MMP#14: Master Meter fluid density

Using: ρP = BCplpCtlp ρ**

Where: Ctlp = Correction factor for effect of temperature on fluid at the Master Meter………………..….


Cplp = Correction factor for effect of pressure on fluid at the Master Meter……………………….


ρP = Base density………………………………………………….{Menu Data: <”Base Density”>}

Calculation Note: Refer to Chapter 16(A) calculations for further information on the CTL and CTS factors

MM#15: New ‘Meter-under-test’ Meter Factor


CVCV

…………………………………………..……{Menu Data: <”Prv run meter factor”>}


Page 16b.8 7955 2540 (Ch16b/BB)

16B.4 Input and output connections for master metering This section is a guide to the inputs and outputs that are required by master meter proving when using a 7955 Flow Computer. A summary is given in Table 16.1 for you to understand the split required when there are also remote ‘Metering’ flow computers. The tables that follow this summary give further details of the connections. Information on the rear panel (pin) connections can be obtained from the guided examples of Chapter 2.

Table 16.1: Summary of master metering connections

7955 ‘Prover’ Flow Computer 7955 ‘Metering’ Flow Computer

• Digital (Status) Inputs for Prover outputs • Status Inputs for valve monitoring

• Digital (Status) Outputs for Prover inputs • Status Outputs for open/close valve control

• Pulse inputs 1 to 4 for local/remote meters • Pulse Input 5 for master flowmeter

• Pulse Inputs 1 to 4 for local meters

• Port for MODBUS communications with remote flow computer – i.e. the slave device

• Port for communications with ‘Prover’ 7955 flow computer – i.e. the Master MODBUS device

• Prover Inlet and Outlet sensors • Metering-run (stream) sensors

Note: When there is only ‘local’ proving required, the combined ‘proving’ and ‘Metering’ 7955 requires all connections

Digital Inputs (1x4x1 System): (Rear panel pin connections are as advised in Chapter 2)

Status Input No. *

7955 FC Metering-

point Comment

5

6 1

05=Meter-point 1 Block valve state ‘A’ : 06=Meter-point 1 Block valve state ‘B’ Called “Valve 1” in software. (Also, read Notes B and C)

7

8 2


9

10 3


11

12 4


13

14 1

13=Prover Isolation valve state ‘A’ : 14=Prover Isolation valve state ‘B’ Called “Valve 5” in software. (Also, read Notes B and C)

15

16 2


17

18 3


19

20 4


21 1 Strainer blockage Input. Active = Blockage + Abort Prove. Read Note A




25

26

(Not Applicable)

25 = Prover outlet valve state ‘A’ : 26 = Prover outlet valve state ‘B’ Called “Valve 9” in software. (Also, read Notes B and C)

* Status Inputs 1 – 4 and 27 – 28 are not applicable to Master Meter Proving

** Assumes input is configured for positive logic

Applicable notes are listed at the end of this Chapter section


7955 2540 (Ch16b/BB) Page 16b.9

Digital Inputs (4x4x4 System): (Rear panel pin connections are as advised in Chapter 2)

Status Input No. *

7955 FC Metering-point Comment

5

6 1


7

8 2


9

10 3


11

12 4


13

14 1


15

16 2


17

18 3


19

20 4






25 (Not Applicable) Flow Direction

* Status Inputs 1 – 4 and 26 – 28 are not applicable to Master Meter Proving

** Assumes input is configured for positive logic

Applicable notes are listed at the end of this Chapter section

Pulse Inputs: (Rear panel pin connections are as advised in Chapter 2)

Pulse Input 7955 FC Meter-point Comment

1 1 Meter pulse count from ‘local’ meter-run flowmeter (Coriolis – support only for single pulse train with no IP252 checking)

2 2 Meter pulse count from ‘local’ Meter-run flowmeter (Coriolis – support only for single pulse train with no IP252 checking)

3 3 Meter pulse count from ‘local’ Meter-run flowmeter (Coriolis – support only for single pulse train with no IP252 checking)

4 4 Meter pulse count from ‘local Meter-run’ flowmeter or Meter pulse count from ‘remote’ Meter-run flowmeter via another 7955

5 (Not Applicable) Master Meter pulse count only - no IP252 checking

Note: Configuration parameters for pulse input connections are as guided in Chapter 11


Page 16b.10 7955 2540 (Ch16b/BB)

Analogue Inputs: (Rear panel pin connections are as advised in Chapter 2)

Measurement * 7955 FC Meter-point Comment

Master Meter Inlet Temperature

(Not Applicable) • Wire element from master meter to a PRT Input on 7955 (4 wire) • Measurement is shared by all metering-points

Master Meter Outlet Temperature

(Not Applicable) • Wire element from master meter to a PRT Input on 7955 (4 wire) • Measurement is shared by all metering-points

Master Meter Inlet Pressure

(Not Applicable) • Wire element from master meter to a 4-20mA input (2 wire) • Measurement is shared by all metering-points

Master Meter Outlet Pressure

(Not Applicable) • Wire element from master meter to a 4-20mA input (2 wire) • Measurement is shared by all metering-points

* Where an installation does not have separate field transmitters for the prover inlet and outlet measurements, you may nominate the same analogue channel for both measurements.

Digital Outputs (1x4x1 System): (Rear panel pin connections are as advised in Chapter 2)

Status Output *

7955 FC Meter-point Comment

5

6 1

05=Meter-point 1 Block valve control (A) : 06=Meter-point 1 Block valve control (B) Called “Valve 1” in software. (Also, read Notes B and C)

7

8 2

07=Meter-point 2 Block valve control ‘A’ : 08=Meter-point 2 Block valve control ‘B’ Called “Valve 2” in software. (Also, read Notes B and C)

9

10 3


11

12 4


13

14 1

13=Prover Isolation valve control ‘A’ : 14=Prover Isolation valve control ‘B’ Called “Valve 5” in software. (Also, read Notes B and C)

15

16 2


17

18 3


19

20 4


21

22 (Not Applicable)

21=Prover outlet valve control ‘A’ : 22=Prover outlet valve control ‘B’ Called “Valve 8” in software. (Also, read Notes B and C)

25 (Not Applicable) ‘Active’ = Start Prove **

* Status Outputs 1 - 4, 23 – 24 are not applicable to master meter proving

** Assumes output is configured for positive logic

Note: When about to start proving a meter, ensure the valve positions of other metering-runs (streams) will not interfere with the proving. Incorrect positioning of valves can prevent the session from starting. Master meter proving will only manipulate the valves related to the meter-under-test.


7955 2540 (Ch16b/BB) Page 16b.11

Digital Outputs (4x4x4 System): (Rear panel pin connections are as advised in Chapter 2)

Status Output *

7955 FC Meter-point Comment

5

6 1

05=Meter-point 1 Block valve control (A) : 06=Meter-point 1 Block valve control (B) Called “Valve 1” in software. (Also, read Notes B and C)

7

8 2


9

10 3


11

12 4


13

14 1


15

16 2


17

18 3


19

20 4


25 (Not Applicable) ‘Active’ = Start Prove **

* Status Outputs 1 - 4, 21 – 24 are not applicable to master meter proving

** Assumes output is configured for positive logic

Note: When about to start proving a meter, ensure the valve positions of other metering-runs (streams) will not interfere with the proving. Incorrect positioning of valves can prevent the session from starting. Master meter proving will only manipulate the valves related to the meter-under-test.


Page 16b.12 7955 2540 (Ch16b/BB)

MODBUS Communications Network Link: This is required when a 7955 Flow Computer is dedicated to proving functions, whilst remote 7955 Flow Computers are dedicated to normal ‘metering’ functions. The flow computers must be interconnected to form a MODBUS network and allow the ‘proving’ 7955 to obtain metering specific data from a remote flow computer for use in a prove session. Refer to Chapter 7 for guidance on MODBUS network connections. Input/Output Connection Notes: A There is a software switch (menu data) for determining if blocked strainers are detected by status inputs or

by mA inputs. By default, the status input method is selected for all strainers. Status Input 4 is allocated to all four strainer inputs; it can be changed using the <Strainer Din source> parameter but you must take care to not clash with a nominated prover and valve I/O map.

Unless the mA method is required, no further configuration is required and the digital inputs table, shown earlier, has a map of these related inputs.

To change over to the 4-20mA (DP) Input method… • Navigate to this menu: <"Configure">/<"Inputs">/<"Strainer input"> • Work through the parameters for each of the four strainers, as guided in Table 16.2.

To revert back to using a status input…

• Navigate to this menu: <"Configure">/<"Inputs">/<"Strainer input"> • Locate the menu data page with “Strainer input src” and edit the option to show “Digital input”

B Valve status signals are received through paired Status Inputs (nominated as ‘A’ and ‘B’ in the Digital

Outputs table). Each valve is allocated a separate pair of inputs. The combinations of active and inactive inputs are then used to differentiate the valve states – see Table 16.3

C Valve control commands are issued through paired Status Outputs (nominated as ‘A’ and ‘B’). Each valve is

allocated a separate pair. Combinations of active and inactive outputs from the paired outputs are used to differentiate the valve commands – see Table 16.4.

Table 16.2: Parameters for 4-20mA (DPIT) Strainer Input

Menu Data (as displayed) Comments and Instructions

Strainer input src • Select the option descriptor containing “mA input” Strainer Ain source • Select the analogue input channel used by the device

Strainer DP @ 100% • Edit a full-scale DP value Strainer DP @ 0% • Edit a value for the lowest DP measurement Strainer DP HI limit • ‘Set’ the threshold for detection of a blockage **

Note: Analogue Input wiring examples can be found in Chapter 2

** Should the selected mA input channel fail, it will also be interpreted as a blockage

= Separate locations for individual configuring each strainer device (and 7955 metering-point)

Table 16.3: Logic Table for Determining Valve States

‘A’ ‘B’ Valve State Comment 0 0 Failed This indicates the existence of a fault condition.




Key: ‘1’ = Active, ‘0’ = Inactive

Table 16.4: Valve Commands

‘A’ ‘B’ Command Comment 0 0 Idle • Valve remains at present position

0 1 Open • Fully open valve

1 0 Close • Fully close valve

1 1 (Not Used) • Never issued from the Flow Computer


7955 2540 (Ch16b/BB) Page 16b.13

16B.5 Configuration Tasks: Proving Details This section explains how to configure basic details for master meter proving and how a proving session should operate. There are separate communication set-up tasks for ‘local’ proving and ‘remote’ proving. Mini-Index

16B.5.1 Configuration Task #1: Meter-run Measurement Functions…………………. 16b.14

16B.5.2 Configuration Task #2: Common Prover details……………….………………16b.16

16B.5.3 Configuration Task #3: Master Meter Proving Details………………..……… 16b.19

16B.5.4 Configuration task #4a: Serial Port Communications (‘local’ prove………… 16b.20

16B.5.5 Configuration task #4b: Serial Port Communications (‘remote’ prove)….…..16b.21


Page 16b.14 7955 2540 (Ch16b/BB)

16B.5.1 Configuration Task #1: Meter-run Measurement Functions (Unless indicated, this task is to be attempted on all Flow Computers performing the ‘Metering’ functions)


1. Ensure that the following measurements/features are configured for metering-points, as appropriate to your installation. (NB. They may have already been pre-configured)

Measurement task Menu data pages to check Which 7955 ?

Flow meter details (Various - See Chapter 11) ‘Proving’ and ‘Metering’

Flow rates (Various - See Chapter 11) ‘Metering’

Metering density Meter run density ‘Metering’

Base density Base density ‘Metering’

Metering temperature MeterRun temperature ‘Metering’

Metering pressure Meter run pressure ‘Metering’

Note: Refer to Chapter 11 for information on configuration these measurements/features

2. Prover Inlet and Outlet Temperature Measurements

Objectives: • Get ‘LIVE’ measurement values on the ‘proving’ 7955.

What to do: (2a) Navigate to this menu: <“Configure”>/<“Temperature”>/<“Prover temp”>

(2b) Work through Table 16.5.

Table 16.5: Inlet/Outlet Prover Temperature


Inlet temp @ 20mA SET a value for the maximum Temperature that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Inlet temp @ 0/4mA SET a value for the minimum Temperature that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Inlet temp src Edit the selection to be the description that corresponds to the input used by the sensor.

Prover in temp LO lmt SET a lower limit for the scaled Inlet Temperature value. An alarm will be raised when this lower limit is exceeded.

Prover in temp HI lmt SET a higher limit for the scaled Inlet Temperature value. An alarm will be raised when this higher limit is exceeded.

Inlet temp FB type (Optional) Select a fallback function - “Last good value” or “Fallback value” - for when the transmitter can not provide a live value.

Inlet temp FB val (Optional) SET a value for the “Fallback value” function (if it is selected).

Inlet temp offset (Optional) Use this for on-line calibration of the transmitter

Prover inlet temp Change the status to be “LIVE”.

Outlet temp @ 100% SET a value for the maximum Temperature that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Outlet temp @ 0% SET a value for the minimum Temperature that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Outlet temp source Edit the selection to be the description that corresponds to the input used by the sensor.

Outlet temp LO lmt SET a low limit for the scaled Inlet Temperature value. An alarm will be raised when this lower limit is exceeded.

Outlet temp HI lmt SET a high limit for the scaled Inlet Temperature value. An alarm will be raised when this higher limit is exceeded.


7955 2540 (Ch16b/BB) Page 16b.15



Outlet temp FB type (Optional) Select a fallback function - “Last good value” or “Fallback value” - for when the transmitter can not provide a live value.

Outlet temp FB val (Optional) SET a value for the “Fallback value” function (if it is selected).

Outlet temp offset (Optional) Use this for on-line calibration of the transmitter.

Prover outlet temp Change the status to be “Live”.

3. Prover Inlet and Outlet Pressure Measurements

Objectives: • Get scaled pressure measurement values. What to do: (3a) Navigate to this menu: <“Configure”>/<“Temperature”>/<“Prover pressure”> (3b) Work through Table 16.6.

Table 16.6: Inlet/Outlet Prover Pressure


Inlet press @ 20mA ‘Set’ a value for the maximum pressure that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Inlet press @ 0/4mA ‘Set’ a value for the minimum pressure that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Inlet press source Edit the selection to be the description that corresponds to the input used by the sensor.

Prover in press LO ‘Set’ a lower limit for the scaled Inlet Pressure value. An alarm will be raised when this lower limit is exceeded.

Prover in press HI ‘Set’ a higher limit for the scaled Inlet Pressure value. An alarm will be raised when this higher limit is exceeded.

Inlet press FB type (Optional) Select a fallback function - “Last good value” or “Fallback value” - for when the transmitter can not provide a live value.

Inlet press FB val (Optional) ‘Set’ a value for the “Fallback value” function (if it is selected).

Inlet press offset (Optional) Use this for on-line calibration of the transmitter

Prover inlet press Change the status to be “Live”.

Outlet press @ 20mA ‘Set’ a value for the maximum pressure that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Outlet press @ 0/4mA ‘Set’ a value for the minimum pressure that is supported by the transmitter. THIS IS NOT APPLICBLE IF USING HART.

Outlet press src Edit the selection to be the description that corresponds to the input used by the sensor.

Outlet press LO ‘Set’ a low limit for the scaled Inlet Pressure value. An alarm will be raised when this lower limit is exceeded.

Outlet press HI ‘Set’ a high limit for the scaled Inlet Pressure value. An alarm will be raised when this higher limit is exceeded.

Outlet press FB type (Optional) Select a fallback function - “Last good value” or “Fallback value” - for when the transmitter can not provide a live value.

Outlet press FB val (Optional) ‘Set’ a value for the “Fallback value” function (if it is selected).

Outlet press offset (Optional) Use this for on-line calibration of the transmitter.

Prover outlet press Change the status to be “Live”.


Page 16b.16 7955 2540 (Ch16b/BB)

16B.5.2 Configuration Task #2: Common Prover details (Unless indicated, this task is to be attempted on the Flow Computer performing the ‘Proving’ functions) Objectives: • Identify the type of Proving required • Provide fundamental information about that Proving • Set limits for the MF (Meter factor) validation process and the stabilisation phase • Set time-outs for the various proving events • Provide optional information for a printed report


1. Navigate to one of these menus: (a) <“Configure”>/<“Inputs”>/<”Flow meter”>/<”Turbine/PD details”>/<”Prover turbine/PD”> or (b) <“Configure”>/<“Inputs”>/<”Flow meter”>/<”Coriolis details”>/<”Prover coriolis”>

2. Work through Table 16.7 (Some menu searching is required.)

Table 16.7: Basic details


Prover meter freq Change status to “LIVE”. (NB. ‘Master’ meter is connected to Pulse Input 5)

Prove freq hi limit Optional alarm limit threshold for the max. ‘Master’ meter pulse frequency

Prv flowstop thresh Minimum tolerated pulse frequency from ‘Master’ meter before Flow Stop

Prove meter factor SET the MF value as given on the calibration sheet for the ‘Master’ meter

3. Navigate to this menu: <“Configure”>/<“Prover”>/<”Common prv details”>


Table 16.8: Prover details


Prover type Select “Master Meter Turb” only if the Master Meter (Prover) is outputting a frequency representing volume. Otherwise nominate “Master Meter Cori”.

Prove by Vol Mass Select either to prove by volume or by mass

(See Section 16B.3 for the various proving scenarios that are supported.)

Prover IO assign Select a ‘Master Meter’ option. This action nominates a valve control and monitoring scheme. (Also, see Section 16B.4 for a map of inputs/outputs)

Prover pipe diameter SET a value for the inner diameter of pipe (at the ‘master’ meter position)

Prv pipe thickness SET a value for the thickness of the of pipe (at the ‘master’ meter position)

Modulus of E SET a value for the modulus of elasticity

Prover cal temp ‘Set’ a value for the temperature at which the ‘master’ meter was calibrated.

Site name (Optional) Edit a site name to be included in the Prover Report.

Meter serial number (Optional) Edit a text label to be included in the Prover Report.

Meter number (Optional) Edit a text label to be included in the Prover Report.

5. Navigate to this menu: <“Configure”>/<“Prover”>/<”Common prv operatn”>


Table 16.9: Common prover operation details

Menu Data Instructions and Comments Prover operation Select the form of interaction between the operator and the ‘Proving’ 7955

Prv calc select Select option to calculate a new ‘Meter Factor’

Prover max runs Select the total number of prove-runs for a prove session.


7955 2540 (Ch16b/BB) Page 16b.17



Required good runs Select the number of consecutive good (passed) prove-runs required for ending a session.

Prv max MF deviation SET a limit (%) for the tolerated deviation for MF values from all prove-runs out of the completed sequence of consecutive passed runs. (NB. 100% switches off this limit)

The deviation calculation and subsequent limit check forms the first part of the MF (Meter factor) validation process. (Also, see pulse count deviation and MF limit check)

Exceeding the index limit will not raise an alarm but it does trigger a fresh attempt to get a complete sequence of consecutive good (passed) prove-runs out of the remaining session.

(The MF deviation calculation is shown under note B)

Prv interp pulse dev SET a limit (%) for the tolerated deviation of pulse counts from all prove-runs out of the completed sequence of consecutive passed runs. (NB. 100% switches off this limit)

This deviation calculation and subsequent limit check forms a middle part of the MF (Meter factor) validation process. It is not performed if the first part of the MF check failed.

Exceeding the index limit will not raise an alarm but it does trigger a fresh attempt to get a complete sequence of consecutive good (passed) prove-runs out of the remaining session.

(The interpolated pulse count deviation calculation is shown under note C)

Prv meter factor LO

Prv meter factor HI

SET a low limit for the average of MF values from all prove-runs out of the completed sequence of consecutive passed runs.

This limit check is the final part of the MF (Meter Factor) validation process and is performed only if the MF deviation is within limits.

Exceeding the limit will not raise an alarm but it does trigger a fresh attempt to get a complete sequence of consecutive good (passed) prove-runs out of the remaining session.

(Read note A)

Prover start delay SET a value for a delay just before the prove-run starts. A zero value = no delay.

Prover start timeout SET a zero value for this delay. It is not applicable to this type of proving

Prover run timeout SET a value for the maximum time allowed for a prove-run to complete (including any programmed delays). A zero value is equivalent to no time allowed

Prv inter-run delay SET a value for the period between any start/end delay for prove-runs during a session. A zero value is equivalent to no time delay

Prover end delay SET a value for a delay immediately following the completion of a prove-run. A zero value is equivalent to no time delay

Prv temperature diff SET a limit for the maximum allowed difference between the operating fluid temperature for the meter-under-test flow point and the averaged temperatures at the Prover Inlet/Outlet valves. This parameter limit check occurs at the end of a prove-run. (Also, read note E)

Prv pressure diff SET a limit for the maximum allowed difference between the operating pressure for the meter-under-test flow point and the averaged pressures at the Prover Inlet/Outlet valves. This parameter limit check occurs at the end of a prove-run. (Also, read note E)

Prv flow rate diff SET a value for the maximum difference between flow at the ‘meter-under-test’ and the ‘master’ meter – checked once every machine cycle and at end of a run. (Also, read note E)

Prv stable timeout SET a value for the period to allow temperatures, pressures and rates of flow to stabilise following valve alignments. This stabilisation phase occurs as soon as valves are aligned. (Also, see limit parameters that follow)

Prv stable temp diff SET a value for the maximum allowed difference between the fluid temperature at the ‘meter-under-test’ flow point and the averaged fluid temperatures at the Prover Inlet/Outlet valves. (Also, read note D)

Prv stablepress diff SET a value for the maximum allowed difference between pressure at the meter-under-test flow point and the averaged pressures at the Prover Inlet/Outlet valves. (Read note D)

See next page for associated notes


Page 16b.18 7955 2540 (Ch16b/BB)

Notes: A MF (Meter factor) validation occurs when there is a number of consecutive good (passed) prove-runs is equal

to the parameter value of <”Required good runs”>.

When the validation check is successful, the session is brought to a graceful end. Otherwise, a fresh attempt is made to get consecutive good runs.

(See notes B and C for calculations performed during the MF validation check) B A deviation calculation is performed at the time of a MF (Meter factor) validity check. (Also, see note A)

Using: MFR =( )

100*Ave

LowHigh

MFMFMF −

Where: MFR = Deviation (%)………………….…….…….….. {Menu Data: <”Prv MF max deviation”>}

HighMF = Highest ‘meter factor’ from completed sequence of passed prove-runs

LowMF = Lowest ‘meter factor’ from completed sequence of passed prove-runs

And: AveMF =( )

2LowHigh MFMF −

C A pulse count deviation calculation is performed as a part of the MF (Meter factor) validation check.

Using: NCR =( )

100*Ave

LowHigh

NCNCNC −

Where: NCR = Pulse count deviation (%)…………….…..... {Menu Data: <”Prv interp pulse dev”>}

HighNC = Highest pulse count from completed sequence of passed prove-runs

LowNC = Lowest pulse count from completed sequence of passed prove-runs

And: AveNC =( )

2LowHigh NCNC −

D This limit is applied once every machine cycle for the duration of the stabilisation phase. Exceeding the limit will not raise an alarm but it will trigger a fresh attempt to detect stability for 10 consecutive machine cycles during the remainder of the phase.

E Exceeding this limit will raise an alarm and record the prove-run as a failure. A fresh attempt is then made to

get the required number of consecutive good (passed) prove-runs from the remainder of the session.


7955 2540 (Ch16b/BB) Page 16b.19

16B.5.3 Configuration Task #3: Master Meter Proving Details (Unless indicated, this task is to be attempted on the Flow Computer performing the ‘Proving’ functions)


1. Navigate to this menu: <“Configure”>/<“Prover”>/<”Master Meter”> 2. Work through Table 16.10.

Table 16.10: Master Meter Proving Details


MM run criteria A prove-run is delimited by achieving an indicated volume or pulse count

MM Pulses required SET a value if the Master Meter (and/or Meter-run Meter) pulse count is the criteria for completion of a run

Prover Volume SET a value if indicated volume of flow measured during a prove-run is the criteria for completion of the run.

Prv expansion coeff SET a value for the prover expansion coefficient.

Prv area expan coeff SET a value for the area expansion coefficient

MM material Free-form text required for printed report

MM serial number Free-form text required for printed report

MM meter number Free-form text required for printed report

Abbreviations: “Prv” = Prover, “MM” = Master Meter, “expan” = expansion, “coeff” = coefficient


Page 16b.20 7955 2540 (Ch16b/BB)

16B.5.4 Configuration task #4a: Serial Port Communications (‘local’ prove)

Objective: • Set-up for a combined ‘Metering’ and ‘Proving’ Flow Computer


1. Navigate to this menu: <“Configure”>/<“Other parameters”>/<“Communications”>/<“MODBUS master”>/<”Slave…”>


Table 16.11: Local Prove Parameters


Slave device 1 func Edit the option descriptor to be “FC PROVER”.

Slv device 1 address SET the value to 0 (for ‘local’ proving)

3. Navigate to the menu: <“Proving”>/<“Device to prove”>

4. Find the menu data page with this description: <“Proving device”>

5. Edit the option to be “Device 1”

(End of Configuration Task)


7955 2540 (Ch16b/BB) Page 16b.21

16B.5.5 Configuration task #4b: Serial Port Communications (‘remote’ prove) Objectives: The ‘Proving’ 7955 Flow Computer should be set-up as a ‘Master’ on a MODBUS network. Other devices, such as the remote ‘Metering’ Flow Computers must be set-up as ‘slaves’ on a MODBUS network. This organisation allows:

1. Parameter values to be transmitted to the ‘Proving’ FC for use during a proving session

2. New meter factors to be forwarded to ‘Metering’ Flow Computers

3. The ‘Proving’ FC to ask the ‘Metering’ FC to control valves and

4. The ‘Metering’ FC to forward valve states to the ‘Proving’ FC. To avoid repetition, the following instructions are written with the assumption that there is a single remote ‘Metering’ Flow Computer. It must be set-up as MODBUS slave.


(Steps 1 to 5 are for the ‘Proving’ Flow Computer)

1. Ensure that a communication port is wired to the same MODBUS network as the remote ‘Metering’ Flow Computer. Also, check the communication parameters on each Flow Computer.

(Note: Refer to Chapter 7 of this manual for a full guide to 7955 Flow Computer communications)

2. Navigate to: <“Configure”>/<“Other parameters”>/<“Communications”>/<“MODBUS master”>


Table 16.12: ‘Remote’ prove communications (‘Proving’ 7955 parameters)


Slave device 1 func Edit the option selected to be “FC PROVER”.

Slv device 1 port no Edit the option descriptor that corresponds to the serial port that is connected to the same MODBUS network as the ‘Metering’ Flow Computer.

Slv device 1 address SET the value to be the same as the MODBUS address of the ‘Metering’ FC

Abbreviations: “func” = function, “Slv” = Slave, “no” = number

4. Navigate to this menu: <“Proving”>/<“Device to prove”>

5. Change the option selected to be “Device 1”.

(Steps 6 to 9 are for the ‘Metering’ Flow Computer)

6. Ensure that a communication port is wired to the same MODBUS network as the ‘proving’ 7955 Flow Computer. Also, check the communication parameters on each Flow Computer.

(Note: Refer to Chapter 7 of this manual for a full guide to 7955 Flow Computer communications)

7. Navigate to this menu: <“Configure”>/<“Other parameters”>/<“Communications”>/<“Ports”>

8. Select the sub-menu for the serial port that is wired to the MODBUS network.

9. Work through Table 16.13. (To avoid repetition, only parameters associated with serial port one are listed.)

Table 16.13: ‘Remote’ prove communications (‘Metering’ 7955 parameters)


Comms port1 owner Change the selection to “Modbus slave”.

P1 MODB slave add SET a value for the MODBUS base address of this ‘Metering’ Flow Computer.

P1 Modbus Features Change the selection to include “Alarm”. This allows the remote ‘Metering’ Flow Computer to inform the ‘Proving’ 7955 Flow Computer of new alarms.

(End of configuration task)


Page 16b.22 7955 2540 (Ch16b/BB)

16B.6 Operating a Prove Session This sub-section shows how a proving session should be operated. Emphasis is placed on use of the front panel keypad. However, the various parameters can be manipulated through a MODBUS network link. Follow these instructions:


Prover max runs Select the total number of prove-runs for a prove session.

Min good runs Select the number of consecutive good (passed) prove-runs required for a proving session to be considered successful.

Flowmeter to prove Select a metering-point:

1 (local meter), 2 (local meter), 3 (local meter) or 4 (local meter or remote meters)

Device to prove If ‘Local’ proving, select “Device 1”. Otherwise, select the MODBUS device number for the ‘remote’ Flow Computer associated with the ‘remote’ meter *

* Refer to Section 16B.5.5 on page 16b.21 if you need to remind yourself of the MODBUS Slave devices known to the ‘Proving’ 7955.

2. Start a session


(2b) Locate this menu data: <”Prover control”>


Note: A session can be aborted at any time by selecting the “Stop” soft-command. 3. Monitor the progress of a prove-run

(3a) Navigate to this menu: <“Proving”>/<“Prover progress”>

(3b) Monitor the <“Prover progress”> menu data page. You will see a message sequence as below

Messages (as displayed) Instructions and Comments

Opening inlet valve Manual Control (+Individual confirmation mode only) Open the Prover Inlet valve and then answer ‘yes’ to the on-screen prompt.


Automatic Control: No action required. The valve is commanded to ‘fully’ open. The 7955 will then expect an ‘opened’ valve state to be returned within the ‘Set’ valve time limit.

Closing block valve Manual Control (+Individual confirmation mode) Close the Meter-run Block valve and then answer ‘yes’ to the on-screen prompt.

Manual Control (+Group confirmation mode) See “Valves aligned?” message prompt that follows.

Automatic Control: No action required. The valve is commanded to ‘fully’ close. The 7955 will then expect a ‘closed’ valve state to be returned within the ‘Set’ valve time limit.


Manual Control (Group confirmation mode only): Open the Prover Inlet valve, close the Meter-run Block valve and then answer “Yes” to the on-screen prompt. Answering “No” will abort the session.

Valves aligned No action required. Flow should be passing meter-under-test + master meter.

Stabilisation. Stabilisation.. Stabilisation...

The Stabilisation phase is as described in Chapter 16. Wait for the stabilisation period to end. The length of time for this is set during a configuration task.

Prover PreRun init No operator action required. This message is not seen unless the machine cycle time is over 2 seconds.

Performing prove run Prove run in progress.


7955 2540 (Ch16b/BB) Page 16b.23


Press any key on the front panel keypad. The next message will then appear.

New MF xxxxxx.xx Old MF xxxxxx.xx

Accept Disregard


Press the blue ‘c’ soft-key to accept the new factor value and allow it to be used in the next machine cycle.

Press the blue ‘d’ soft-key to NOT accept the new factor value and, therefore, continue using the existing ‘Meter Factor’.


New KF xxxxxx.xx Old KF xxxxxx.xx

Accept Disregard

This message will not appear if the minimum number of consecutive good prove-runs is not achieved or if a new ‘Meter factor’ is required instead of a new ‘K factor’.

Press the blue ‘c’ soft-key to accept the new factor value and allow it to be used in the next machine cycle.

Press the blue ‘d’ soft-key to NOT accept the new factor value and, therefore, continue to use the existing factor value.


Prove print report? Yes No

Press the blue ‘c’ soft-key to transmit a report through the port that is configured for a direct connection to an ASCII compatible output device (e.g. printer or terminal).

Press the blue ‘d’ soft-key to NOT print a report at this time. It can always be printed later through the PRINTER MENU.

Opening block valve Manual Control (Individual confirmation mode) Open the meter-run block valve and then answer ‘yes’ to the on-screen prompt.

Manual Control (Group confirmation mode): See “Valves aligned?” message prompt.

Automatic Control: No action required. The valve is commanded to be ‘fully’ open. The 7955 will expect an ‘open’ valve state to be detected within a set time limit.

Closing inlet valve Manual Control (Individual confirmation mode) Open the Prover Inlet valve and then answer ‘yes’ to the on-screen prompt.

Manual Control (Group confirmation mode) See “Valves aligned?” message prompt.

Automatic Control: No action required. The valve is commanded to ‘fully’ close. The Flow Computer will then expect a ‘closed’ valve state to be detected within a set time limit.


Manual Control (Group confirmation mode) Open the Meter-run Block valve, close the Prover Isolation (Inlet) valve and then answer “Yes” to the on-screen prompt. Answering “No” will abort the session.

Valves returned No action required

End of prv session No action required. Optional report is transmitted through a communications port.

Note: Additional prompts appear when a batch transaction is in progress - these are for retrospective calculations. In addition, batch reports can be transmitted through a communication port during a prove session.

6. Navigate to the menu <“Proving”>/<“Last meter factor”> to see the accepted/unaccepted meter factor value.

7. Review information recorded from sessions by looking under the <”Prover”>/<”Prover log”>/<”Master Meter”> menu or (if printed) examining the “Master Meter Prover Report”.

(End of Proving Session)


Page 16b.24 7955 2540 (Ch16b/BB)

16B.7 Archiving of Proving Information The 7955 is permanently configured to record proving information in a tamper-proof archive. Information (data values) from an entire session, including all prove-passes and prove-runs, is stored in the Prover Archive. The capacity of this archive is 1 session.

A complete set of values from any prove-run of the session can be displayed for viewing or for retrieval by an external Modbus networked device, but can not be printed out through a serial port. Editing of an archived value is not possible. Each attempt to edit a displayed value (from the archive) will see an “*** Access denied ***” message.

Although the Prove Archive is a fixed size and operates independently of all other data archiving activities, it is worth reading about other Archiving facilities. (See Chapter 9)

The Prover Archive display is located within this menu: <“Proving”>/<“Prover log”>/<”Master meter”>.

Table 16.14: Archived Session Data

Menu Data * What is this data? Prv session status • Final status of the proving session

Prv MM flow rate • Average rate of flow at the master meter

Prv old K factor • Previous/existing K Factor

Prover new K factor • Generated K factor

Prv old meter factor • Previous/existing Meter Factor

Prv new meter factor • Generated Meter Factor

Prv MF deviation • Deviation figure for the Meter Factor generated after each prove-run

Prv count deviation • Uncorrected pulse count deviation

MF dev (old/new) • Deviation figure for the existing MF and the generated MF

* Abbreviations: “Prv” = Prover, “MF” = Meter factor, “dev” = deviation

Table 16.15: Archived Master Meter (MM) Prove-run Data

(Use the <”View prove run data”> parameter to choose another prove-run: 0 = last run, 1 = 1st run, etc.)


Prv run status Final status of selected prove-run

Prv run pulse count Uncorrected pulse count for the prove-run

Prv run MM K Factor K Factor generated at the end of the prove-run

Prv run MM Ind Vol Indicated Volume rate of flow at the end of the prove-run

Prv run MM Ind mass Indicated Mass rate of flow at the end of the prove-run

Prv run prv temp Average of Prover Inlet and Outlet temperature measurements during the run

Prv run prv press Average of Prover Inlet and Outlet pressure measurements during the prove-run

Prv run MM MFactor Meter Factor generated at the end of the prove-run

Prv run CTLp Correction Factor for effect of temperature on fluid passing the master meter

Prv run CPLp Correction Factor for effect of pressure on fluid passing the master meter

Prv run CTSp Correction Factor for effect of temperature on the prover-loop

Prv run CPSp Correction Factor for effect of pressure on the prover-loop

Prv run CCFp Combined Correction Factor – for prover-loop flow rates

Prv run corr vol Corrected Prover Volume – See page 16b.3 for calculations

PrvRun MM CorrPrvMas

Correct Prover Mass – See page 16b.3 for calculations

* Abbreviations: “Prv” = Prover, “ind” = indicated, “temp” = temperature, “press” = pressure,

“MFactor” = Meter factor, “Vol” = volume, “corr” = corrected, “MM” = Master Meter, “Mas” = Mass


7955 2540 (Ch16b/BB) Page 16b.25

Table 16.16: Archived ‘Meter under test’ (MUT) Prove-run Data

(Use the <”View prove run data”> parameter to choose another prove-run: 0 = last run, 1 = 1st run, etc.)


Prv run corr pulse Corrected (interpolated) pulse count for the run – See page 16b.3 for calculations

Prv run MUT K Factor K Factor generated at the end of the prove-run – See page 16b.3 for calculations

Prv run MUT Ind Vol Meter-under-test Indicated Volume rate of flow at the end of the prove-run

Prv run SUT ind mass Meter-under-test Indicated Mass rate of flow at the end of the prove-run

Prv run stream temp Meter-run temperature measurements at the end of the prove-run

Prv run stream press Meter-run pressure measurements at the end of the prove-run

Prv run meter factor Meter Factor generated at the end of the prove-run

Prv run CTLm Correction Factor for effect of temperature on fluid passing the meter-under-test

Prv run CPLm Correction Factor for effect of pressure on fluid passing the meter-under-test

Prv run CCFm Combined Correction Factor – for meter-run flow rates

Prv run CorrMeterVol Meter-under-test Corrected Volume Rate– See page 16b.3 for calculations

* Abbreviations: “Prv” = Prover, “ind” = indicated, “temp” = temperature, “press” = pressure,

“Vol” = volume, “Corr” = corrected, “MUT” = Meter-under-test, “SUT” = Stream-under-test


Page 16b.26 7955 2540 (Ch16b/BB)

16B.8 Prover Reporting The ‘Proving’ 7955 offers to printout a proving report at the end of a prover session. Alternatively, it can be printed on-demand by a making an appropriate selection from within the PRINTER (soft-key) menu.

Master Meter report formats can be seen on pages 16b.27 and 16b.28.

16B.8.1 Print Requests using the front panel keyboard (Ensure that an RS-232C port is configured for the connection to an ASCII compatible output device)


1. Press the grey PRINT-MENU soft-key

2. Navigate to this menu: <“Print report”>/<“Print”>

3. Press the ‘b’ soft-key

4. Use the UP-ARROW key to scroll through the list of reports

5. Press the ENTER key when “Prover report” appears on line two.



7955 2540 (Ch16b/BB) Page 16b.27

Figure 16.2: Format of Master Meter Printed Report - Volume

Master Meter Summary Report – Volume

Prove report number: xx Site location: xxxxxxxx Start time: dd/mm/yyyy hh:mm:ss Duration: xx.xxx s ======================================================================= Master Meter Details Serial number xxxxxxx Meter number xxxxxxxx Internal dia x.xxx m Wall thickness x.xxx m Meter material xxxxxxx Modulus of E. xxxxxxx.xxx N/m2 Meter expans coeff x.xxx PPM/Deg.C Cal temp. xx.xxx Deg.C Flow rate x.xxx m3/s ======================================================================= Master Meter Run Data Run1 Run2 Run3 Run4 Run5 (1) Pulses xxxxx.xx xxxxx.xx xxxxx.xx xxxxx.xx xxxxx.xx (2) K factor pulse/m3 xxxx.xxx xxxx.xxx xxxx.xxx xxxx.xxx xxxx.xxx (3) Ind vol (1/2) m3/s x.xxx x.xxx x.xxx x.xxx x.xxx (4) Master temp Deg.C xx.xxx xx.xxx xx.xxx xx.xxx xx.xxx (5) Master press bar abs x.xxx x.xxx x.xxx x.xxx x.xxx (6) Master MF x.xxx x.xxx x.xxx x.xxx x.xxx (7) CTLp x.xxx x.xxx x.xxx x.xxx x.xxx (8) CPLp x.xxx x.xxx x.xxx x.xxx x.xxx (9) CTSp x.xxx x.xxx x.xxx x.xxx x.xxx (10) CPSp x.xxx x.xxx x.xxx x.xxx x.xxx (11) CCFp (7*8*9*10) x.xxx x.xxx x.xxx x.xxx x.xxx (12) Corr prover vol(3*11) x.xxx x.xxx x.xxx x.xxx x.xxx ======================================================================= Meter Under Test

Meter serial number xxxxxxxxxx Meter number xxxxxxxxxx Old K factor xxxx.xxx pulse/m3, Old meter factor x.xxx Count deviation x.xxx %, MF deviation x.xxx ======================================================================= Meter Under Test Run Data Run1 Run2 Run3 Run4 Run5 (13) Interpolated Pulses xxxxx.xx xxxxx.xx xxxxx.xx xxxxx.xx xxxx.xxx (14) K factor pulse/m3 xxxx.xxx xxxx.xxx xxxx.xxx xxxx.xxx xxxx.xxx (15) Ind vol(13/14) m3/s x.xxx x.xxx x.xxx x.xxx x.xxx (16) Meter temp Deg.C xx.xxx xx.xxx xx.xxx xx.xxx xx.xxx (17) Meter press bar abs x.xxx x.xxx x.xxx x.xxx x.xxx (18) CTLm x.xxx x.xxx x.xxx x.xxx x.xxx (19) CPLm x.xxx x.xxx x.xxx x.xxx x.xxx (20) CCFm (18*19) x.xxx x.xxx x.xxx x.xxx x.xxx (21) Corr meter vol(20*15) x.xxx x.xxx x.xxx x.xxx x.xxx (22) Meter Factor (12/21) x.xxx x.xxx x.xxx x.xxx x.xxx ======================================================================= New meter factor x.xxxxx New K factor (Old K factor / NewMF) xxx.xxxxx Meter factor deviation from previous x.xxx % ====================================================================== Remarks: ________________________________________________________________________ ________________________________________________________________________ Signature: Date: Company: ____________________ ______________ _____________________ Signature: Date: Company: ____________________ ______________ _____________________


Page 16b.28 7955 2540 (Ch16b/BB)

Figure 16.3 : Format of Master Meter Printed Report - Mass

Master Meter Summary Report – Mass

Prove report number: xx Site location: xxxxxxxx Start time: dd/mm/yyyy hh:mm:ss Duration: xx.xxx s ======================================================================= Master Meter Details Serial number xxxxxxx Meter number xxxxxxxx Internal dia x.xxx m Wall thickness x.xxx m Meter material xxxxxxx Modulus of E. xxxxxxx.xxx N/m2 Meter expans coeff x.xxx PPM/Deg.C Cal temp. xx.xxx Deg.C Flow rate x.xxx kg/hour ======================================================================= Master Meter Run Data Run1 Run2 Run3 Run4 Run5 (1) Pulses xxxxx.xx xxxxx.xx xxxxx.xx xxxxx.xx xxxxx.xx (2) K factor pulse/kg xxxx.xxx xxxx.xxx xxxx.xxx xxxx.xxx xxxx.xxx (3) Ind mass(1/2) kg x.xxx x.xxx x.xxx x.xxx x.xxx (4) Master temp Deg.C xx.xxx xx.xxx xx.xxx xx.xxx xx.xxx (5) Master press bar abs x.xxx x.xxx x.xxx x.xxx x.xxx (6) Master MF x.xxx x.xxx x.xxx x.xxx x.xxx (7) CTLp x.xxx x.xxx x.xxx x.xxx x.xxx (8) CPLp x.xxx x.xxx x.xxx x.xxx x.xxx (9) CTSp x.xxx x.xxx x.xxx x.xxx x.xxx (10) CPSp x.xxx x.xxx x.xxx x.xxx x.xxx (11) CCFp (7*8*9*10) x.xxx x.xxx x.xxx x.xxx x.xxx (12) Corr prover mass(3*11) x.xxx x.xxx x.xxx x.xxx x.xxx ======================================================================= Meter Under Test

Meter serial number xxxxxxxxxx Meter number xxxxxxxxxx Old K factor xxxx.xxx pulse/m3, Old meter factor x.xxx Count deviation x.xxx %, MF deviation x.xxx ======================================================================= Meter Under Test Run Data Run1 Run2 Run3 Run4 Run5 (13) Interpolated Pulses xxxxx.xx xxxxx.xx xxxxx.xx xxxxx.xx xxxx.xxx (14) K factor pulse/kg xxxx.xxx xxxx.xxx xxxx.xxx xxxx.xxx xxxx.xxx (15) Ind mass(13/14) kg x.xxx x.xxx x.xxx x.xxx x.xxx (16) Meter temp Deg.C xx.xxx xx.xxx xx.xxx xx.xxx xx.xxx (17) Meter press bar abs x.xxx x.xxx x.xxx x.xxx x.xxx (18) CTLm x.xxx x.xxx x.xxx x.xxx x.xxx (19) CPLm x.xxx x.xxx x.xxx x.xxx x.xxx (20) CCFm (18*19) x.xxx x.xxx x.xxx x.xxx x.xxx (21) Corr meter mass(20*15) x.xxx x.xxx x.xxx x.xxx x.xxx (22) Meter Factor (12/21) x.xxx x.xxx x.xxx x.xxx x.xxx ======================================================================= New meter factor x.xxxxx New K factor (Old K factor / NewMF) xxx.xxxxx Meter factor deviation from previous x.xxx % ====================================================================== Remarks: ________________________________________________________________________ ________________________________________________________________________ Signature: Date: Company: ____________________ ______________ _____________________ Signature: Date: Company: ____________________ ______________ _____________________


7955 (CH17/AB) Page 17.1

17. HART, SMART and the 7955

17.1 What this chapter tells you This chapter is a comprehensive guide for understanding how the 7955 Flow Computer can be set-up for digital communications with “SMART” † type field transmitters.

Important Notice

This chapter is only relevant to 7955’s with the “HART” add-on board installed.

17.2 Introduction to SMART and HART with the 7955 A special add-on board‡ is required to be installed inside the 7955 before this facility is enabled. This board provides all the necessary hardware and firmware support for the 7955 to communicate as a Current Input Device (Primary Master) on two separate two-wire, 4-20mA loops of “SMART” transmitters (Slaves).

Warning!! Each network loop must have no more than five “SMART” field transmitters connected at

any one time. Exceeding this number will damage add-on boards.

The following “safe area only” diagram shows all the HART network loops with the maximum number of “SMART” field transmitters connected to each loop. In practice, far fewer transmitters are used.

Take note of the warnings - above and below. Section 17.3 has details of external wiring involving the 7955.

HART Channel 2

HART Channel 1

T1 T2 T3 T4 T5

T1 T2 T3 T4 T5

HART Channel 4

HART Channel 3

T1 T2 T3 T4 T5

d

b

c

HART 1 Value0.125

Live

a

T1 T2 T3 T4 T5

Warning!! Connecting up “SMART” transducers has to be done with great care. Powering-up more than

one point-to-point configured transmitter on a HART network loop can produce an electrical current (20mA per transmitter) that can damage the 7955.

The communications standard for each network loop is the HART§ Protocol**. A full technical discussion of this standard is outside the scope of this operating manual. There is a detailed discussion of the HART protocol in the Rosemount booklet entitled “HART Field Communications Protocol - A Technical Description”. However, particularly important aspects involving the 7955 are covered in later section as they are needed.

† A “SMART” transmitter is said to be intelligent because it contains a micro-processor that provides extra functionality. This may

take various forms, such as on-board calculations, handling multiple sensors, combining types of measurement. measurement integrity indicators, and so on. “SMART” is also used for the ability to re-use existing field wiring.

‡ Part number is 79557 § This is an acronym for “Highway Addressable Remote Transducer”. HART is a registered trademark of the HART

Communication foundation. **

Implementation conforms to revision 5.5 of the HART protocol specification.


7955 (CH17/AB) Page 17.2

Application software is able to request data from dynamic variables that are kept and maintained by a “SMART” transmitter. These dynamic variables can be thought of as being very much like 7955 type data locations. Four dynamic variables per “SMART” field transmitter can be requested. A total of sixteen dynamic variables can be input to the 7955. Configuration details concentrate on setting up the 7955 to obtain up to eight (the maximum) measurement values.

HART 6

HART 8

HART 9

HART 7

HART 10

HART 11

HART 12

HART 13

Address = 1

HARTTransmitter

Primary

Secondary

Third

Fourth

Variables

Address = 9

HARTTransmitter

Primary

Secondary

Third

Fourth

Variables

HART network loop 2

Address = 1

HARTTransmitter

Primary

Secondary

Third

Fourth

Variables

Address = 8

HARTTransmitter

Primary

Secondary

Third

Fourth

Variables

7955 HART Inputs

HART network loop 1

HART 4

HART 5

HART 2

HART 3

HART 14

HART 15

HART 1

HART 16

Figure 17.1: Example of 2 HART Network Loops


7955 (CH17/AB) Page 17.3

17.3 Connecting the 7955 to a HART network loop This section covers installation issues for analogue input wiring involving the 7955.

17.3.1 7955 electrical connections and impedance requirements HART connections use analogue inputs 13, 14, 15 and 16 for HART network loops 1, 2, 3 and 4 respectively. The HART add-on board provides the hardware support for these inputs to become “SMART” analogue inputs.

Analogue input Signal +


7955


Analogue input Signal -

100 Ohms

"SMART"Field

Transmitter

+

-Active

impedance

Note:To ensure reliableoperation, it is goodpractice to groundthe 0V d.c. isolatedsupply at one point.

Figure 17.2: “SMART” Analogue input on the HART add-on board (Internally powered)

Every analogue input on the 7955 Flow Computer utilises a internal 100Ω current sense resistor. The circuitry for the “SMART” analogue inputs on the HART add-on board use a 100Ω current sense resistor in series with an active impedance. The total impedance is then sufficient for reliable operations at HART signal frequencies, while minimising the dc voltage drop across the 7955 Flow Computer terminals. This allows a sufficient voltage at the field transmitter even when powered through I.S. Barriers (or Isolators). Parameter notes: 1. At d.c., the voltage drop at the maximum current of 22mA is 3.4V 2. Minimum impedance in the HART extended frequency band (500 -10khz) is 330Ω 3. Maximum impedance in the HART extended frequency band (500 -10khz) is 480Ω


Pin function D-Type Pin no.

D-Type Pin Designation

+24V d.c. (isolated supply) SK3/34 +24V Analogue

Analogue input signal + SK3/40 Analog i/p 13 +

Analogue input signal - SK3/39 Analog i/p 13 -

0V d.c. (isolated supply) SK3/18 0V Analogue





Analogue input signal + SK3/6 Analog. i/p 14 +

Analogue input signal - SK3/22 Analog. i/p 14 -



7955 (CH17/AB) Page 17.4















17.3.2 Frequency-shift keying The HART protocol uses the American “Bell 202” standard frequency-shift keying (F.S.K.) method to mask a digital signal on to analogue wiring.

Important Notice The “HART” add-on board provides 4 HART channels that utilise existing Analogue Inputs (13, 14, 15 and 16). This allows SMART and Non-SMART instruments to use an analogue input at the same time. However, the F.S.K. signal produces random errors on the analogue signal which affect the normal accuracy (See Appendix ‘C’). We strongly recommend that analogue inputs being used for HART loop inputs should only be used for HART communications.

17.3.3 Cable choice and the 65μs rule There is a standard “65μs” rule that determines the maximum length of cable that can be used for reliable operation of the HART network loop.

Step 1: Add up all the resistance in the network loop.

• 7955 current sense resistance is equivalent to 350Ω with the HART add-on board.

• I.S. Barrier or Isolator

• Cable

Step 2: Find out the total cable capacitance

Step 3: Multiply the total resistance * total cable capacitance.

The resulting value must be less than 65μs.

We can provide multi-pair cable that has a maximum capacitance of 115 pF/m. The following table shows the recommended maximum cable lengths for typical HART network loops with this cable.


7955 (CH17/AB) Page 17.5

Table 17.1: Maximum cable lengths No. of slaves

Loop resistance

Max. Cable length

1 No Barrier 1171m

1 150Ω 884m

1 300Ω 713m

2 No Barrier 1136m

2 150Ω 846m

2 300Ω 673m

3 No Barrier 1101m

3 150Ω 807m

3 300Ω 633m

4 No Barrier 1067m

4 150Ω 769m

4 300Ω 593m

5 No Barrier 1032m

5 150Ω 730m

5 300Ω 553m

Table notes:

1. Cable length calculations take into account the 350Ω resistance from a 7955 with the HART Board.

2. It is assumed that a 150Ω I.S. Barrier has a maximum end to end resistance of 185Ω.

3. It is assumed that a 300Ω I.S. Barrier has a maximum end to end resistance of 340Ω.

A discussion of cable choices can be found in the Rosemount booklet entitled “HART Field Communications Protocol - A Technical Description”.

Important Notice: Field transmitters in hazardous areas

Always follow wiring instructions provided by manufacturers of the field transmitters.


7955 (CH17/AB) Page 17.6

17.4 Configuring the 7955 to use a HART network loop

17.4.1 Configuring by using the software wizard This sub-section covers step-by-step instructions for using a software wizard to configure a 7955 that has the following set-up:

Example 1

A HART network loop with one “SMART” static pressure field transmitter is attached to analogue input 15. The objectives of this example are:

• to set a multi-drop address

• to get static pressure from the fourth dynamic variable (on the transmitter) into the first HART data location dedicated to holding input values

• to allocate the first HART data location to the Line pressure calculation


Go to the wizard selection menu

1. Press the MENU key so that page 1 of the main menu appears.

2. Use the DOWN-ARROW key until the “Configure” main menu option is

displayed.

3. Press the blue key that is alongside the “Configure” option

4. Press the ‘a’ key twice.

Select the Hart inputs wizard

5. Press the ‘b’ key and then use the DOWN-ARROW key to scroll through a

list of wizards.

6. Press the ‘b’ key when “Hart inputs” appears on the display.

Select HART Input 1 7. Press the ‘d’ key to answer “yes” to the prompt.

Choose the HART network loop

8. “HART 1 PhyLinkNo” is set to “HART link 1” by default. This example

involves HART network loop 1 (i.e. HART link 1) so there is no need to

change the setting.

However, If anything other than “HART link 1” is shown:

• Press the ‘b’ key and then use the DOWN-ARROW key to scroll

through the options.

• Press the ‘b’ key when “HART link 1” is displayed.

9. Press the ENTER key to continue to the next step.

Choose the address of the “Field transmitter”

10. Press the ‘b’ key

11. Use the DOWN-ARROW key to scroll through the options until

“HART address 5” is shown.

12. Press the ‘b’ key to confirm this selection


Choose the fourth dynamic variable



“Fourth variable” is shown.



Choose the type of dynamic variable



“Static press (G)” is shown.

20. Press the ‘b’ key to confirm this selection.


Select the averaging mode 22. Press the ENTER key to keep existing setting and continue to next step.


7955 (CH17/AB) Page 17.7

Put the field transmitter on-line


24. Use the DOWN-ARROW key to scroll through the options until “On line”

is shown.



Monitor the response from issuing the on-line/off-line command

27. Watch the response message. It should cycle from “None” to “Configured”

in less than a minute. Note: The response “SMART error” may appear if

there is there is a problem with the HART loop.


Change status to get live values from the field transmitter

29. Press the ‘d’ key

30. Use the DOWN-ARROW key to scroll through the options until “Live”

is shown.

31. Press the ‘b’ key to confirm this selection. Live static pressure values

(gauge units) should now be displayed.


Skip remaining questions 33. Press the ‘c’ key to answer “no” to the prompt.

34. Repeat step 3 until the “Hart inputs” wizard is completed.

Allocate the HART data input location`

35. Use the “Pressure” wizard to make data location HART value 5 the source

for the Line pressure calculation. Note: During the “Pressure” wizard,

“Line press source” should be set to “HART input 5”.

(End of Example)

To view results after exiting the wizard, look in the menu :<“Health check”>/<“Inputs”>


7955 (CH17/AB) Page 17.8

17.5 Post configuration - viewing HART data This sub-section provides a complete check-list of all the data locations associated with checking information returning from HART network loops.

Task 1: Checking the results

Step 1: Select this menu : <“Health check”>/<“Inputs”>

Step 2: Look at data shown in this check-list

Data name Instructions and Comments

HART input 1 value

HART input 2 value

HART input 3 value Values from sixteen dynamic variables

HART input : value

HART input 16 value

HART software ver • HART board firmware identification.

HART no. of phy links • This shows the number of HART network loops. Default setting is “None”

HART status • This shows a digit for each of the sixteen HART data location inputs: Digit = ‘0’ - Input is not configured (not in use) Digit = ‘1’ - Input is configured (in use) Digit = ‘2’ - Input configuration failed due to an error

• Note: Default state is 0000000000000000

17.6 SMART units of measurement Support is provided for a sub-set of the SMART units of measurement

Temperature Density Pressure Mass rate 1. Deg.C. 1. g/cc 1. In WG 1. g/sec 2. Deg.F 2. g/m3 2. mm WG 2. g/Min 3. Kelvin 3. lb/gallon (UK) 3. Bar 3. h/Hour 4. lb/ft3 4. mBar 4. Kg/sec

5. Kg/litre 5. Pa 5. Kg/Min 6. g/litre 6. MPa 6. Kg/day 7. lb/in3 7. In HG 7. Tonnes/Min 8. Tonnes/Hour

9. Tonnes/Day 10. Lb/sec 11. Lb/Hour 12. Lb/Day

Note:

Data values received in un-supported measurement units are displayed without units of measurement - line 3 of the display is blank. However, calculations that use this data always assume the default units of measurement. For temperature data, this would be “Deg.C”. Refer to Chapter 9 for a full list of supported units of measurement.

Chapter 18 Batching (Transactions)

7955 2540 (CH18/AE) Page 18.1

18. BATCHING (TRANSACTIONS) This chapter explores the 7955 support for Standard Batch Operations and optional Retrospective Calculations.

18.1 Standard Batch Operations 18.1.1 Batch Operation Types

The Flow Computer offers five types of batch operation:

(1) Daily

This type of batch commences at a programmed (SET) hour – known as the contract hour. The duration is 24 hours at all times, unless the calendar clock is adjusted. Batches are back-to-back and therefore have to be halted on-demand by a menu ‘soft-command’

(2) Timed

This type of batch commences when a programmed (SET) date and time matches that of the Flow Computer calendar clock. Time is the key parameter for completing a batch. The duration of a batch is a fixed, user-programmed period. Batches are always back-to-back and have to be halted on-demand by a menu ‘soft-command’ or a soft-key. A guided example starts on page 18.9

(3) Manual Trigger

This type of batch is started by selecting a ‘soft-command’. User- intervention is the essential parameter for starting and completing a batch. The duration of a batch is therefore entirely dependent on when the “stop” ‘soft-command’ is selected. Batches are not back-to-back unless commands are issued in quick succession. A guided example starts on page 18.7

Alternatively, the bottom blank soft-key can start and stop a batch. (4) Product Change Trigger

This type of batch is started and terminated by detecting a change of product in the pipeline. Interface detection – a feature described in Chapter 11 – provides the key parameter and is monitored for change once during each machine cycle. Batches are always back-to-back and have to be halted on-demand by a menu ‘soft-command’. A guided example starts on page 18.11

(5) Programmed Quantity

This type is more sophisticated than the previously mentioned types. A chain of 6 back-to-back batches can be set-up, each batch with parameters for programming the quantity to deliver, the optional delivery rate and start method. The chain can be linked such that it is continuously repeated.

An individual quantity-based batch transaction can commence either by:

(i) Selecting a ‘soft-command’ (ii) Starting at a pre-set date and time (iii) Starting immediately after being enabled

Product flow is the key parameter for completing a batch. The batch is complete when a pre-set quantity of the measured product has been delivered – quantity is in terms of mass flow, gross volume flow or net volume flow.

By default, flow control is by means of automatically opening and closing a stream block valve at the start and end of a quantity batch. The subject of “Valve Control and Monitoring” is dealt with in Chapter 16 – some configuration is required.

An alternative option is for the 7955 Flow Computer to continuously control the rate of product flow, thus giving a more precise delivery of the product during each batch transaction. Flow Delivery Control (FDC) features an auto-configured PID algorithm that can manipulate a proportionally controlled valve1. After a flow-controlled batch is underway, the user can adjust the deliverable quantity, abort batches, or pause/resume the batch. System alarms flag events, such as completion or approaching end of batch.

Table 18.1 on page 18.2 summarises the availability of FDC options.

1 The Flow Control Valve is expected to be independent of the valves used during a proving session.


Page 18.2 7955 2540 (CH18/AE)

Table 18.1: Availability of Optional Features

Batch Type * Pause/Resume? Qty Adjustment? Over-spill limit?

Timed No No No

Manual No No No

Product No No No

Quantity (FDC) Yes Yes Yes Quantity (w/o FDC) No No No

* Abbreviations used: “FDC” = Flow Delivery Control, “w/o” = without


7955 2540 (CH18/AE) Page 18.3

18.1.2 Batch Operation Parameter Reference This Section is a reference for all the parameters associated with batch transaction operations.

Points To Observe

1. Batch operation types will not operate together. A batch type is exclusively selected at that moment of it being enabling by a ‘soft-command’. This action also halts existing batch activities, therefore excluding other batch types. 2. There are menu system areas for viewing the records of the previous and current batch transactions. (See Menu: <“Batching”>) 3. The transaction record of a completed batch is automatically archived. (See “Archiving” in Chapter 9)

Menu Navigation List: (1) <“Configure”>/<“Batching”> and (2) <“Batching”> Menu Data List (1 of 3): * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? 1 Batch start time 26 Prog1 quantity 2 Timed batch duration 27 Prog1 flow rate I 3 Batch time enable H:1&3 28 Prog1 start type 4 SingleRun bch enable H:1&3 29 Prog1 start time 5 Station batch enable 30 Prog1 name 6 Current product ID 31 Prog1 next program D

7 Product batch mode 32 Meter run density * 8 Product batch enable 33 Base Density *

9 Qty unit-type select A 34 Degrees API *

10 Qty batch enable H, 35 Meter Factor *

11 Qty batch pause G, 36 Flowmeter K factor *

12 Batch status 37 BS&W value *

13 Batch qty delivered E, 38 CTL

14 Batch qty remaining E, 39 CPL

15 Starting program ID 40 Meter temperature *

16 Current program ID 42 Meter pressure *

17 Batch manual trigger H, 43 Base density oil

18 Adjust batch qty L, 44 Oil degrees API *

19 Modified batch qty (L), 45 Meter kinematic visc *

20 Qty overrun limit 46 Combined cor factor *

21 PID flow control (E), K, O 47 Std volume water% *

22 Flow ramp limit (K) 48 Meter CSW

23 Trickle flow rate (K), 49 Base density water *

24 Meter run max flow (K), - Flow status (F),

25 Batch auto print J - Operating mode B,

Associated notes follow the next menu data list. (X) - Referenced in note X

Figure 18.1: Batching Operation Parameters

Copy overat end of

batch


XX

Previous Batch(Menu)

21

Manual BatchSet-up

4 5

7 8

127bBatch

Recording

Product (Zone)Batch Set-up

Timed BatchSet-up

OR

3

Current Batch(Menu)

50a

6

To

To

Flow Ratesand Totals

32

Quantity Batching(& Flow Control)

9 10 11

12

15 17

1926

Program #1

31To

Programs#2 to #30

Optional

49To

25

25

25

13 14

16

18

20 21

22 23 24

50b 127b


Page 18.4 7955 2540 (CH18/AE)

Menu Data List (2 of 3): * shows data that can be “Live” or “Set”

Index Menu Data (as displayed) Notes? Index Menu Data (as displayed) Notes? CURRENT BATCH TRANSACTION RECORD PREVIOUS BATCH TRANSACTION RECORD

50a Batch ticket number M, 50b Batch ticket number M, 51a Batch status 51b Batch status 52a Product name 52b Product name 53a Program name 53b Program name 54a Batch start time C:06, 54b Batch start time 55a Bch start meter temp C:02, 55b Bch start meter temp 56a Bch start meter pres C:03, 56b Bch start meter pres 57a Bch start meter dens C:07, 57b Bch start meter dens 58a Bch start IV total C:01, 58b Bch start IV total 59a Bch start GV total C:01, 59b Bch start GV total 60a Bch start ISV total C:01, 60b Bch start ISV total 61a Bch start GSV total C:01, 61b Bch start GSV total 62a Bch start mass total C:01, 62b Bch start mass total 63a Start NV oil total C:01, 63b Start NV oil total 64a Start NSV oil total C:01, 64b Start NSV oil total 65a Start NM oil total C:01, 65b Start NM oil total 66a Start NV water total C:01, 66b Start NV water total 67a Start NSV water tot C:01, 67b Start NSV water tot 68a Start NM water total C:01, 68b Start NM water total 69a Ind vol total C:01, 69b Ind vol total 70a Gross vol total C:01, 70b Gross vol total 71a Ind std vol total C:01, 71b Ind std vol total 72a Gross std vol total C:01, 72b Gross std vol total 72a Mass total C:01, 72b Mass total 73a Oil vol total C:01, 73b Oil vol total 74a Oil std vol total C:01, 74b Oil std vol total 75a Oil mass total C:01, 75b Oil mass total 76a Water vol total C:01, 76b Water vol total 77a Water std vol total C:01, 77b Water std vol total 78a Water mass total C:01, 78b Water mass total 79a Alarm total C:01, 79b Alarm total 80a Flowmeter errors C:10, 80b Flowmeter errors 81a Stn ind vol total C:01, 81b Stn ind vol total 82a Stn gross vol total C:01, 82b Stn gross vol total 83a Stn ind std vol totl C:01 83b Stn ind std vol totl 84a Stn gro std vol totl C:01 84b Stn gro std vol totl 85a Stn mass total C:01 85b Stn mass total 86a Stn oil vol total C:01 86b Stn oil vol total 87a Stn oil std vol totl C:01 87b Stn oil std vol totl 88a Stn mass total C:01 88b Stn mass total 89a Stn water vol total C:01 89b Stn water vol total 90a Stn water stdvol tot C:01 90b Stn water stdvol tot 91a Stn water mass total C:01 91b Stn water mass total 92a Current IV total C:01, 92b Bch close IV total 93a Current GV total C:01, 93b Bch close GV total 94a Current ISV total C:01, 94b Bch close ISV total 95a Current GSV total C:01, 95b Bch close GSV total 96a Current mass total C:01, 96b Bch close mass total 97a Current NV oil total C:01, 97b Close NV oil total 98a Current NSV oil tot C:01, 98b Close NSV oil tot 99a Current NM oil total C:01, 99b Close NM oil total

100a Current NV water tot C:01, 100b Close NV water tot 101a Current NSV water total C:01, 101b Close NSV water tot 102b Current NM water tot C:01, 102b Close NM water total

“IV” = Indicated Volume, “ISV” = Indicated Standard Volume, “GV” = Gross Volume, “GSV” = Gross Standard Volume, “NV” = Net Volume, “NSV” = Net Standard Volume, “NM” = Net Mass, “av” = average, “dens” = density, “Bch” = Batch


7955 2540 (CH18/AE) Page 18.5

Menu Data List (3 of 3): * shows data that can be “Live” or “Set”


CURRENT BATCH TRANSACTION RECORD PREVIOUS BATCH TRANSACTION RECORD 103a Batch program ID 103b Batch program ID

104a Batch request qty 104b Batch request qty

105a Modified batch qty 105b Modified batch qty

106a Batch qty delivered 106b Batch qty delivered

107a Batch qty remaining 107b Batch qty remaining 108a Batch average temp C:02, 108b Batch av meter temp

109a Batch average press C:03, 109b Batch av meter press

110a Batch av meter dens C:07, 110b Batch av meter dens

111a Batch av base dens C:08, 111b Batch av base dens

112a Batch av degrees API C:09, 112b Batch av degrees API

113a Batch av kine visc C:11, 113b Batch av kine visc

114a Batch average MF C:10, 114b Batch av MeterFactor

115a Batch av K factor C:10, 115b Batch av K factor

116a Batch av base BS&W C:05, 116b Batch av base BS&W

117a Batch average BS&W C:05, 117b Batch average BS&W

118a Batch average CSW C:05, 118b Batch average CSW 119a Batch average CTL C:04, 119b Batch average CTL

120a Batch average CPL C:04, 120b Batch average CPL

121a Batch average CCF C:10, 121b Batch average CCF

122a Batch av oil bdens C:05 122b Batch av oil bdens

123a Batch av oil deg API C:05 123b Batch av oil deg API

124a Current date/time C:06, 124b Batch close time

125a Current meter temp C:01, 125b Batch close meter temp

126a Current meter pres C:02, 126b Batch close meter press

127a Current meter dens C:07, 127b Batch close meter dens

“IV” = Indicated Volume, “ISV” = Indicated Standard Volume, “GV” = Gross Volume, “GSV” = Gross Standard Volume,

“NV” = Net Volume, “NSV” = Net Standard Volume, “NM” = Net Mass, “av” = average, “dens” = density, “Bch” = Batch

Notes:

Separate location value (and state) for each of four metering-points but accessible through same menu page.

A By default, gross volume is the selected unit of measurement for monitoring product flow during a quantity-based batch transaction. Alternative units of measurement for selection are net volume (NV) and mass.

B Batch transactions require the Flow Computer to be operating in “Normal” mode. [‘i’ soft-key menu]

C:<n> Use Table 18.2 to help identify the initial data source for batch transaction record parameters

D This parameter is for chaining one batch transaction program to another batch transaction program. The “None” option is for ending the chain.

Table 18.2: Batch Transaction Record – Parameter Source Reference

Ref. No. Source Category

1 Normal mode (Main/Standard) total 2 Metering Temperature 3 Metering Pressure 4 API Referral 5 Net Oil/’Water’ Calculations 6 7955 Calendar Clock 7 Metering density 8 Base density 9 API Degrees

10 Flow Metering 11 Viscosity


Page 18.6 7955 2540 (CH18/AE)

E Due to the mechanics of batching, the delivered quantity may exceed the pre-set quantity. However, this

over-spill can be minimised by using the Flow Delivery Control option. Over-spill is not filtered out of batch records. (Also, see Note F)

Over-spill due to Flow Computer timing is minimised to the delay from the method of recording values at some time during a machine cycle.

F Limit alarm threshold for monitoring the over-spill of a batch. An over-spill in excess of the (upper) limit will raise a “Qty batch overrun” alarm. The alarm can be cleared when the batch is completed and there is a ‘flow stopped’ state.

This alarm limit check will not operate unless Flow Delivery Control is active and the programmed threshold is greater than zero. (Also, see Note E)

G Pause and resume controls are available when running a quantity-based batch transaction with active Flow

Delivery Control. The ‘pause’ ‘soft-command’ allows a live adjustment to the deliverable quantity. Adjustments take effect immediately upon resumption of the batch. (See Table 18.1 for availability of other batch features.)

H (1) Activating another batch type will immediately terminate all existing batch activities.

There are termination exceptions:

• A quantity batch cannot be stopped without using the “Halt” ‘soft-command’ (of <“Qty batch enable”>). Otherwise, attempts to enable another batch type will fail and result in a “Qty batch running” (INFO class) system alarm. This INFO alarm can be accepted and cleared at any time.

• A quantity batch (with active Flow Delivery Control) cannot be enabled unless the Flow Computer is in a ‘flow stopped’ state. Otherwise, attempts will fail and result in a “Qty batch start F” (INFO class) system alarm. This alarm can be accepted and cleared at any time.

(2) A quantity batch with a manual trigger must first be enabled with <“Qty batch enable”> and then triggered by <“Batch manual trigger”>. Further triggering may be needed if other chained programs use a manual start.

(3) Terminating a running batch will leave both current and previous batch records with identical values until a new batch is started.

I Target flow rate for achieving the “maintain” state during a quantity batch. This parameter is not applicable unless

using the Flow Delivery Control feature. (Also, read Note K and see Table 18.1 for availability of FDC) J Enable or prevent an automatic printout of the batch report immediately on completion of a batch. A serial

communication port will need to be configured for a connection to an ASCII compatible printer. K A quantity type batch can use the 7955 software based PID algorithm to manipulate a proportional valve and

therefore control the product delivery rate. (Read Note O)

The ‘On’ ‘soft-command’ will auto-configure most PID parameters apart from the gain, the integral and the derivative. (See “PID” reference pages in Chapter 9)

Associated Flow Delivery Control Parameters:

• <“Trickle flow rate”> This will specify the minimum flow rate for the automated closing stage of a batch. A default value of 0 forces the 7955 Flow Computer to assume the

‘trickle’ is 2% of the value ‘Set’ for <“Meter run max flow “>.

• <“Flow ramp limit”> This will override the limit that appears within the PID configuration menu.

• <“Meter run max flow”> This is a capping limit for achieving the target flow rate. (Also, read Note I) L Pause a quantity-based batch, ‘SET’ a new deliverable quantity and then resume the batch. (Requires FDC)

M Cumulative count for the number of batch reports produced. This count cannot be reset to zero on-demand but will rollover to zero after exceeding 4.95 billion.

N Applicable only when using retrospective calculations.

O When not using PID Control (Flow Delivery Control), it is necessary for the Flow Computer to auto-control a stream block valve. Set-up details are as guided in the “Valve Control and Monitoring” section of Chapter 16. It is also necessary that you select a pre-built map of status I/O assignments – maps are listed in Chapter 16.

To check on and select an I/O assignment… • Navigate to this menu: <”Configure”>/<”Prover”>/<”Common prv details”> • Locate the <prover I/O assignment> (or similar) parameter and edit as necessary


7955 2540 (CH18/AE) Page 18.7

18.1.3 Guided Example 1: Manual Trigger Type Batch This example demonstrates how a manually triggered type is configured and operated.

What to do: Read the overview and then browse through the operating events list and associated parameter list for this example. Adapt the example to match your requirements.

Overview: This type of batch is started by selecting a “Run” ‘soft-command’. User- intervention is the essential parameter for starting and completing a batch. The duration of a batch is therefore entirely dependent on when the “Halt” ‘soft-command’ is selected.

Batches are not back-to-back unless a “Start & stop next” ‘soft-command’ is used to perform a combined start-stop-start action. The alternative method is to issue separate “Run” and “Halt” ‘soft-commands’ in quick succession.

Figure 18.2 gives a graphical overview for the example. It shows single-shot batches, each varying in duration by operator intervention and, consequently, indirectly varying the quantity delivered. The batches are totally unaffected by the flow conditions at any metering-point, which are reasonably stable in this case. Product flow is not controlled by the 7955 Flow Computer.

Interface detection also has no effect on a manual batch transaction, as illustrated by the two different batch transactions in Figure 18.3. Although metering-points of a 4x4x4 scheme have been used to highlight independence from product change, it should be noted that a 1x4x1 scheme is equally independent.

Figure 18.2: Manual Batch Type - unaffected by flow

B1 B2

Time

Tracked Product Flow(Active metering-points)

"Halt""Run"(Enable & Trigger)

"Halt" "Run"

Flo

w(m

3 /hour)

(Tank A) (Tank B)

"In progress""Complete"

"In progress" "Complete"

Batch Status(of all metering-points)

Tracked Product Flow(Inactive metering-points)

Figure 18.3: Manual Batch Type - unaffected by product

Product Mix (Slops)

Product 1

Product 2

De

nsi

ty(K

g/m

3)

Time


"Halt" "Run"

B2

(Tank B)

B1

(Tank A)

"In progress" "Complete" "In progress"

Tracked Product Flow(4x4x4 Metering-point)


Tracked Product Flow(4x4x4 Metering-point)

"Complete"


Page 18.8 7955 2540 (CH18/AE)

Operating Events: (Events are associated with Figure 18.2 on page 18.7)

1 Flow increases independently of Flow Computer

2 Operator uses the “Run” ‘soft-command’ when flow rate is adequate. Batch B1 starts immediately, with the batch status changing to “In progress”

3 Batch B1 continues and product flow remains stable until ‘Tank A’ approaches full capacity

4 Flow decreases independently of Flow Computer

5 Batch B1 completes when the operator selects the “Halt” ‘soft-command’. The batch status then changes from “In progress” to “Complete”

6 Batch B2 does not start yet. There is a wait until ‘Tank B’ is ready

7 Flow rate increases independently of Flow Computer

8 Operator uses the “Run” ‘soft-command’ when flow rate is adequate. Batch B2 starts immediately, with the batch status changing to “In progress”

9 Batch B2 continues and product flow remains stable until ‘Tank B’ approaches full capacity

10 Flow decreases independently of Flow Computer

11 Batch B2 completes when the operator selects the “Halt” ‘soft-command’.

Table 18.3: Manually Triggered Batch Type - Associated Parameter List

Menu Data (as displayed) Example Value/Option Comment and Instructions

SingleRun bch enable “Run” * • Single-run mode only – ‘soft-command’ for enabling and triggering individual batches. (It will switch-off station mode)

Station batch enable ** “Run” * • Station mode only – ‘soft-command’ for enabling and triggering single batch. (It will switch-off single-run mode)

Batch status *** (See “Operating Events”) • Useful for monitoring the batch operation.

* “Halt” ‘soft-command’ is for completing a batch and deselecting batch type. “Stop & start next” is for a start-stop-start action

** Alternatively, the bottom, blank soft-key can start and stop a batch for all metering-points at the same time

*** Viewed from within the menu presenting the current batch transaction record

Note: The MENU NAVIGATION LIST is on page 18.3

Note: A Configuration of the manual batch type is simplified to the selection of an operation mode. There are two

operation modes to choose from – at any time - and they are mutually exclusive:

A station mode batch transaction uses all active metering-points (runs/streams) for a single batch. Station totals in the current record are updated during each cycle. Individual metering-point (“metering-run”) totals are also updated. (Opening/Closing totals are unaffected by the mode)

The single-run mode involves an individual metering-point being used for an individual batch, but allows up to four batches to be recorded at the same time. Individual metering-point (“metering-run”) totals in the current batch record are updated once every cycle. Station totals are also updated. (Opening/Closing totals are unaffected)


7955 2540 (CH18/AE) Page 18.9

18.1.4 Guided Example 2: Timed Batches This example demonstrates how the timed batch type is configured, commenced at a programmed date and time, and halted on-demand.

What to do: Read the overview and then browse through the operating events list and associated parameter list for this example. Adapt the example to match your requirements. Overview: Figure 18.4 gives a graphical overview for the example. It shows a series of back-to-back batches, each programmed to last 300 seconds. The first batch commences - triggers - when the 7955 Flow Computer calendar clock matches a SET date and time, “08-12-1999 08:00:00”. Timed batch operations are totally unaffected by the flow conditions, which are reasonably stable in this case. Batch Bn is interrupted 200 seconds after starting, following the selection of a “Halt” ‘soft-command’. Interface detection also has no effect on a timed batch transaction, as illustrated by the timed batch transactions in Figure 18.5. Although metering-points of a 4x4x4 scheme have been used to highlight independence from product change, it should be noted that a 1x4x1 scheme is equally independent. Timed batches operate in station mode only, whereby all active metering-points (runs/streams) are used for a single batch. During a batch, the Station totals in the current batch record are updated once every machine cycle. The individual metering-point (‘metering-run’) totals in the current record are not updated.

Figure 18.4: Timed Batch Type - unaffected by flow

Flo

w(m

3 /h

ou

r)

B1

Time

"Halt"

"Run"(Enabled)

08-12-199908:00:00

B2 B3

08-12-199907:51:00

(Trigger)

(300s) (300s) (300s) (n-1)*300sBn

(200s)

"In progress""Complete"

Tracked Product Flow(1x4x1/4x4x4 metering-point)



Figure 18.5: Timed Batch Type - unaffected by product change

Product Mix (Slops)

Product 1

Product 2Densi

ty(K

g/m

3)

Time

"Halt""Run"(Enable)

Date/TimeTrigger

B1

(300s)B2 B3

(300s) (300s)

"In progress"




"Complete"


Page 18.10 7955 2540 (CH18/AE)

Operating Events:

(Events are associated with Figure 18.4 on page 18.9)

1 Configure associated parameters in the sequence as guided in Table 18.4

2 Wait for the 7955 Flow Computer calendar clock to match the trigger date and time

3 Trigger occurs on 8th December 1999 at 8 o’clock in the morning. Batch B1 starts immediately

4 Batch B1 completes after 300 seconds and batch B2 starts immediately

5 Batch B2 completes after a further 300 seconds and batch B3 starts immediately

6 Batch B3 completes after a further 300 seconds

7 Batches continue …

8 Later on, batch Bn starts

9 After 200 seconds, the “Halt” ‘soft-command’ is selected. Batch Bn ends immediately but it is still considered to be complete - the batch status shows “complete”

10 To resume this timed batch operation, program a new date and time, adjust the duration if necessary and then re-select the “Run” ‘soft-command’.

Note:

If there is a loss of power, the above must be set-up again so that the 7955 Flow Computer has a new start-time.

Table 18.4: Timed Batch Type - Associated Parameter List

Menu Data (as displayed) Example Value/Option Comments and Instructions

Timed batch duration 300.0s • 300 seconds per batch

Batch time enable “Run” • ‘Soft-command’ for enabling the timed batch type

Batch start time * 08-12-1999 08:00:00 • Trigger for first batch is 8th. December 1999 at 8am

Batch status ** In Progress Compete • Useful for monitoring the general batch operation

* “00-00-0000 00:00:00” = Start first batch immediately after editing duration and selecting the “Run” ‘soft-command’

** Viewed from within the current batch transaction record

Note: The MENU NAVIGATION LIST is on page 18.3


7955 2540 (CH18/AE) Page 18.11

18.1.5 Guided Example 3: Product Zone Triggered Batches This example demonstrates how a product zone triggered batch type is configured and operated.

What to do: Read the overview and then browse through the operating events list and associated parameter list for this example. Adapt the example to match your requirements.

Overview: Figure 18.6 gives a graphical overview for this example. It depicts several batches where the duration is controlled by a change of product. (Density or S.G. zones from interface detection define product bands). Interface Detection – described in Chapter 11 - supplies a <current product ID> for the batching process to identify a product change and then begin/end a batch transaction. You must configure Interface Detection to operate with either metering-run density zoning or specific gravity zoning.

Figure 18.6: Product Zone Type Batch

Product Mix (Slops)

Product 1

Product 2

B1 B3 B4

Density(Kg/m3)

Time



B2

"In progress"

Batch Status(of the metering-point)

"Complete"


1 Configure associated parameters in the order as listed in the table below

2 Operator uses the “Run” ‘soft-command’ when the density of product ‘2’ is adequate. Batch B1 starts immediately, with the batch status changing to “In progress”

3 Density increases (due to external influence)

4 Batch B1 completes when the measured density is outside the density zone for product ‘2’. Batch B2 starts immediately on completion of batch B1

5 Density continues to increase (due to external influence)

6 Batch B2 completes when measured density enters the density zone for product ‘1’. Batch B3 starts immediately on completion of batch B2

7 Batch B3 completes when the measured density is outside the density zone for product ‘1’. Batch B4 starts immediately on completion of batch B3

8 Batch B4 completes when the operator selects the “Halt” ‘soft-command’.


Page 18.12 7955 2540 (CH18/AE)

Table 18.5: Product Zone Triggered Batch Type - Associated Parameter List

Menu Data *** (as displayed) Example Value/Option Comment

Product batch mode “Station” or “Meter run” • Select station mode or single-run mode. (Note A)

Product batch enable * “Run” • “Run” is the ‘soft-command’ for enabling and triggering batch for any batch mode

Current program ID (Interface Detection) • The key control parameter. (See Chapter 11)

Batch status ** (See “Operating Events”) • Useful for monitoring the batch operation.

* “Halt” option is the ‘soft-command’ for completing a batch and also deselecting the batch type

** Viewed from within the menu presenting the current batch transaction record

*** The MENU NAVIGATION LIST is on page 18.3

Note: A A station mode batch transaction uses all active metering-points (runs/streams) for a single batch. This is

suitable for a 1x4x1 system. The alternative, single-run mode, involves an individual metering-point being used for an individual batch, but allows up to four batches to be recorded at the same time. This is suitable for a 4x4x4 system.


7955 2540 (CH18/AE) Page 18.13

18.1.6 Guided Example 4: Quantity Batch with FDC - Single Program Loop This example demonstrates how a quantity batch program can be chained to itself such that it is continually repeated until halted on-demand.

What to do: Read the overview and then browse through the operating events list and associated parameter list for this example. Adapt the example to match your requirements. (The menu navigation list is on page 18.3) Overview: Figure 18.7 gives a graphical overview for the example. It shows the same quantity batch program (BP1) repeated twice. Batch program BP1 is configured with various details (see Table 18.6), including a requirement to start the batch transaction manually with a “Run” ‘soft-command’. The first batch transaction is started by the “Run” (manual trigger) ‘soft-command’ whilst the Flow Computer is in a ‘flow stopped state’. FDC - Flow Delivery Control - is then responsible for delivering the pre-set quantity, with minimal over-spill, and ending the batch. The duration of this batch transaction can vary and this is due to differing flow conditions. A product change has no effect on the batch transaction. After the first batch transaction is complete, quantity-type batching remains enabled. The subsequent batch transaction (batch program BP1) is triggered manually at any convenient time. The loop can be repeated any number of times until the “Halt” (enable/disable) ‘soft-command’ is selected, when no more quantity batching is needed. Directly associated parameters are listed on page 18.14. All other parameters, such as the Gross Volume flow rate, are identifiable from the reference information in Section 18.1.2.

Figure 18.7: Quantity Batch with FDC - Repeated Program

BP1 BP1 titi ti

Flow(m3/hour)

Time

"Run"(Trigger)

Target Flow Rate

"Run"(Trigger)

Flow StopThreshold

"Halt"'Trickle'Rate

Achieved


ti

Variable Time IntervalBatch Status

1

"Ramp up"

2 3 5 6

"Maintain" "Ramp down" "Stopping" "Idle"1 2 3 5 64 "Trickle"

N

4


1 Quantity batch operation type enabled when the “Run” (enable/disable) ‘soft-command’ is selected

2 Flow is reduced by some means - on-line or off-line valve control - and falls below the programmed (SET) ‘flow stop’ threshold. The 7955 Flow Computer is then in a ‘flow stopped’ state

3 The first batch (BP1) starts immediately when the “Run” (manual trigger) ‘soft-command’ is selected.

4 Flow Delivery Control increases flow to match the programmed target rate (from batch program ‘1’)

5 Flow Delivery Control maintains flow at the target rate until 98% of the pre-set quantity is delivered


Page 18.14 7955 2540 (CH18/AE)

(Operating Events continued…)

6 Flow Delivery Control decreases flow to match the programmed trickle rate (from batch program ‘1’)

7 Batch stops when all the pre-set quantity is delivered. Quantity batch status displays “Idle”.

8 The second batch (BP1) starts immediately when the “Run” ‘soft-command’ is selected.

9 Flow Delivery Control increases flow to match the programmed target rate (of batch program ‘1’)


11 Flow Delivery Control decreases flow to match the programmed trickle rate (of batch program ‘1’)

12 Batch stops when all the pre-set quantity is delivered

13 Quantity type batching is deactivated (disabled) by selecting a “Halt” (enable/disable) ‘soft-command’

Table 18.6: Quantity Batch Type - Directly Associated Parameters (for Guided Example 4)

Menu Data (as displayed) Example Value/Option Comment and Instructions

Qty unit-type select (Any “volume” option) • Either “Gross Volume” or “Net Volume”

PID flow control “On” • Activate Flow Delivery Control (FDC). Read Note C

Flow ramp limit 100% • FDC Parameter: 100% = Allow any ramp-up rate

Trickle flow rate 120 m3/hour • FDC Parameter: Minimum flow rate for end of batch

Meter run max flow 400 m3/hour • FDC Parameter: Maximum flow rate at any time

Oty overrun limit 0 m3 • 0 = No over-spill limit check

Starting program ID “Program 1” • Chain begins with Batch Program ‘1’

Prog1 quantity 1000 m3 • Deliverable quantity excluding adjustments and over-spill

Prog1 flow rate 200 m3/hour • Target rate to be maintained by FDC for batch peak. Note A

Prog1 start type “Manual start” • Manual trigger requirement

Prog1 name “Test Prog 1” • Free-form text of up to 20 characters

Prog1 next program “Program 1” • Chain ends with Batch Program ‘1’. This forms the loop

Qty batch enable Stn qty batch enable

“Run” • Choose one mode (single-run/station parameter) to enable the quantity batch type. (Read Note A)

Batch manual trigger * “Run” • The Trigger for each programmed manual batch

Batch status ** In Progress Compete • Useful for monitoring the general batch operation

Batch status *** (See Operating Events) • Useful for monitoring the quantity batch operation

Batch qty delivered (Increasing as delivered) • Useful for monitoring the quantity batch operation

Batch qty remaining (Decreasing as delivered) • Useful for monitoring the quantity batch operation

* “Halt” option is the ‘soft-command’ for stopping the program loop

** Viewed from within the current batch transaction record *** Viewed from within the “Batching” configuration menu

Abbreviations used: “Stn” = Station, “Prog” = (Batch) Program, “ID” = Identification/Identifier

Notes: A Some parameters are seemingly duplicated under the <”Station batch”> menu (for station mode operations)

and under the <”Meter run batch”> menu (for single-run mode operations). They are not duplicated and you must USE ONLY ONE SET OF PARAMETERS depending on the mode you require

A Station mode batch transaction uses all active metering-points (metering-runs/streams) for a single batch. This is suitable for a 1x4x1 system. The alternative, single-run mode, involves an individual metering-point being used for an individual batch, but allows up to four batches to be recorded at the same time. This is suitable for a 4x4x4 system.

B When using the station mode of operation, the target flow rate is an overall target value rather than a target

for an individual metering-point C It is essential to review and configure other PID software parameters – See Chapter 9 for details


7955 2540 (CH18/AE) Page 18.15

18.1.7 Guided Example 5: Quantity Batch with FDC - Pause and Resume Controls This example demonstrates how a batch can be paused for any period and then resumed. What to do: Read the overview and then browse through the operating events list and associated parameter list for this example. Adapt the example to match your requirements. Overview: Figure 18.8 gives a graphical overview of this example. It shows a single-shot quantity batch (BP2) that is paused mid-way for a period of time ‘tI’ and then resumed until the pre-set quantity is delivered. Batch program BP1 is configured with various details (see Table 18.7), including a requirement to start the batch transaction with a “Run” ‘soft-command’. FDC - Flow Delivery Control - is responsible for delivering the pre-set quantity, with minimal over-spill, and ending the batch. The duration of this batch transaction can vary and this is due differing flow conditions. A product change has no effect on the batch transaction. Directly associated parameters are listed in Table 18.7 on page 18.16. All other parameters, such as the Gross Volume flow rate, are identifiable from the reference information in Section 18.1.2.

Figure 18.8: Quantity Type Batch with FDC - Pause/Resume Control

BP2 BP2 titi ti

Flow(m3/hour)

Time

"Run"(Trigger)

Target Flow Rate

"Resume"(Command)

Flow StopThreshold

"Halt"(Disable)

'Trickle'Rate

Achieved

Tracked Product Flow1x4x1/4x4x4 meter-point

ti

Variable Time IntervalBatch Status

1

"Ramp up"

2 3 5 6

"Maintain" "Pausing"1 2 3 4 "Paused"

N

"Run"(Enable)

4

"Stopping" "Idle"7 86 "Trickle"

1 2 7

"Ramp up"5

"Pause"(Command)


1 Quantity batch operation type enabled when the “Run” (enable/disable) ‘soft-command’ is selected

2 Flow is reduced by some means - on-line or off-line valve control - and falls below the programmed (SET) ‘flow stop’ threshold. The 7955 Flow Computer is then in a ‘flow stopped’ state

3 Batch BP2 starts immediately when the “Run” (manual trigger) ‘soft-command’ is selected

4 Flow Delivery Control increases flow to match the programmed target rate (from batch program ‘2’)

5 Flow Delivery Control maintains flow at the target rate until the ‘Pause’ ‘soft-command’ is selected

6 Flow Delivery Control decreases flow to achieve a ‘flow stopped’ state

7 Batch BP2 resumes when the ‘Resume’ ‘soft-command’ is selected


Page 18.16 7955 2540 (CH18/AE)

(Operating Events continued…)

8 Flow Delivery Control increases flow to match the programmed target rate (of batch program ‘2’)


10 Flow Delivery Control decreases flow to match the programmed trickle rate (of batch program ‘2’)

11 Batch BP2 stops when all the pre-set quantity is delivered

12 Quantity type batching is deactivated (disabled) by selecting a “Halt” (enable/disable) ‘soft-command’

Table 18.7: Quantity Batch Type - Directly Associated Parameters (for Guided Example 5)

Menu Data (as displayed) Value/Option Comment

Qty unit-type select (Any “volume” option) • Either Gross Volume or Net Volume units of measurement

PID flow control “On” • Activate Flow Delivery Control (FDC). Read Note C

Flow ramp limit 100% • FDC Parameter: 100% = Allow any ramp-up rate

Trickle flow rate 120 m3/hour • FDC Parameter: Minimum flow rate for end of batch

Meter run max flow 500 m3/hour • FDC Parameter: Maximum flow rate at any time

Oty overrun limit 0 m3 • 0 = No over-spill limit check

Starting program ID “Program 2” • Chain begins with Batch Program ‘1’

Prog2 quantity 1500 m3 • Deliverable quantity excluding adjustments and over-spill

Prog2 flow rate 400 m3/hour • Target rate to be maintained by FDC for batch peak. Note A

Prog2 start type “Manual start” • Manual trigger required

Prog2 name “Test Prog 2” • Free-form text of up to 20 characters

Prog2 next program “None” • No more links in this batch program chain

Qty batch enable Stn qty batch enable

“Run” • Choose one mode (single-run/station parameter) to enable the quantity batch type. (Read Note A)

Batch manual trigger * “Run” • The trigger for a programmed manual batch

Qty batch enable “Pause” “Resume” • Pause/Resume ‘soft-command’s for mid-way through batch

Batch status ** “In Progress” “Compete” • Useful for monitoring the general batch operation

Batch status *** (See Figure 18.8) • Useful for monitoring the quantity batch operation

Batch qty delivered 0 1500 + Over-spill • Useful for monitoring the quantity batch operation

Batch qty remaining 1500 0 • Useful for monitoring the quantity batch operation

* “Halt” option is the ‘soft-command’ for stopping the program loop

** Viewed from within the current batch transaction record *** Viewed from within the “Batching” configuration menu

Abbreviations used: “Stn” = Station, “Prog” = (Batch) Program, “ID” = Identification

Notes: A Some parameters are seemingly duplicated under the <”Station batch”> menu (for station mode operations)

and under the <”Meter run batch”> menu (for single-run mode operations). USE ONLY ONE SET OF PARAMETERS

A Station mode batch transaction uses all active metering-points (metering-runs/streams) for a single batch. This is suitable for a 1x4x1 system. The alternative, single-run mode, involves an individual metering-point being used for an individual batch, but allows up to four batches to be recorded at the same time. This is suitable for a 4x4x4 system.

B When using the station mode of operation, the target flow rate is an overall target value rather than a target C It is essential to review and configure other PID software parameters – See Chapter 9 for details


7955 2540 (CH18/AE) Page 18.17

18.1.8 Printing Batch Reports Batch reports can output by using one of several methods:

1. Method: On-demand This feature requires no configuration apart from setting up an RS232C port, as guided in Chapter 7. To activate, press the PRINT-MENU soft-key and then select the “Print report” menu option. Now choose a report by selecting from the multiple-choice options. Table 18.8 shows the relevant options for the batch reports. Each report has two varieties – a single-stream version and a multiple-stream version. The version printed depends on the type of batch transaction and depends on whether the single-run mode or station mode has been selected.

Table 18.8: Descriptors for Printed Batch Reports

Option (as displayed) Purpose of option

“Current batch” • Printout the “Current” batch (transaction) record in a report format

“Previous batch” • Printout the “Previous” batch (transaction) record in a report format

2. Method: Automatic Printed Report The Flow Computer can be configured to automatically printout a report on completion of a batch transaction.

Activation instructions:

1. Navigate to this menu: <”Configure”><”Batching”>/<”Batch report print”> 2. Select the “On” option

All methods require an RS232C communications port to be set-up for connection to a printer or other ASCII compatible output device. Printed reports are transmitted in an ASCII format through the port configured exclusively for this type of connection (i.e. <Port owner> = ”Printer”).

When a batch report is first printed, it is stamped with “ORIGINAL”. All subsequent printouts of the same report will be stamped with “DUPLICATE”. However, the “current” batch report is stamped with “DUPLICATE” only if the report values have not changed.

Note: If the 7955 Flow Computer is making use of a communications port, ensure that the port is not allocated to another task (e.g. peer-to-peer operations).


Page 18.18 7955 2540 (CH18/AE)

Figure 18.9: "Current Batch" Printed Report

EXAMPLE

ONLY

EXAMPLE

ONLY

BATCH TRANSACTION RECORDOperators Signature: .......................................Report printing time: XX/XX/XXXX XX:XX:XX

Tag number XXXXXXXXXXXXXX

Batch ticket number XXX

Batch status XXXXXXXXXXXXXX

Product nameProgram name

Batch base temp XX.XXX Deg.C

Batch base pressureBatch equilib press

Batch start timeBatch finish time

X.XXXXX bar abs

X.XXXXX bar abs

XX/XX/XXXX XX:XX:XX

Bch start meter temp XX

XXXXXXXXXXXXXX

Meter Run Data

1 2 3 4

Current meter temp XX

Bch start meter pres XX.XXXXX

Current meter presBch start meter densCurrent meter dens

XX.XXXXX

XXX

XXX

Opening/Closing Cumulative Totals

Bch start IV totalCurrent IV totalBch start GV totalCurrent GV total

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

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XXX

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XXX

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X.XXXXXe+XX

Bch start ISV totalCurrent ISV total

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

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Bch start GSV totalCurrent GSV total

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

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X.XXXXXe+XX

Bch start mass totalCurrent mass total

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

Batch Totals

Ind vol totalGross vol totalInd std vol total

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XXGross std vol totalMass totalAlarm totalFlowmeter errors

X.XXXXXe+XX

X

X

Deg. C.

Deg. C.

bar abs

bar abs

kg/m3

kg/m3

m3

m3

m3

m3

std m3

std m3

std m3

std m3

kg

kg

m3

m3

std m3

kg

XX/XX/XXXX XX:XX:XX

Batch revision XXX

Previous revision XXX

XXXXXXXXXXXXXX

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X.XXXXXe+XX

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X

X

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std m3

Station Batch TotalsStn Ind vol totalStn gross vol totalStn ind std vol totl

X.XXXXXe+XX

X.XXXXXe+XX

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X.XXXXXe+XXStn gro std vol totlStn mass total X.XXXXXe+XX

Deg.C

bar abs

kg/m3

kg/m3

cSt

m3

m3

std m3

std m3

kg

X.XXX

Quantity Batch TotalsBatch program IDBatch request qtyModified batch qty

Batch average tempBatch average pressBatch av meter densBatch av base densBatch av degrees API

Batch average MFBatch av K factorBatch average CTLBatch average CPL

Batch average BS&W

X.XXX

X.XXX

XXXXXXXXXX

X.XXX

************* END OF REPORT **********

X.XXX

Weighted Averages

Batch av kine visc

Batch average CCFBatch av base BS&W

Batch average CSWBatch av oil bdensBatch av oil deg APIBatch av oil water dens

X.XXX

X.XXX

X.XXX

X.XXX

X.XXX

X.XXX

X.XXX

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X.XXX

X.XXX

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%

%

kg/m3

kg/m3

Original/duplicate XXXXXXXXXX

Alarm CountsAlarms during batch X

If alarm count is not zero, refer to alarm history log to obtain alarm details.

Note: Net oil/water data not shown due to net calculations not being enabled


7955 2540 (CH18/AE) Page 18.19

Figure 18.10: "Previous Batch" Printed Report

EXAMPLE

ONLY

EXAMPLE

ONLY

BATCH TRANSACTION RECORDOperators Signature: .......................................Report printing time: XX/XX/XXXX XX:XX:XX

Tag number XXXXXXXXXXXXXX

Batch ticket number XXX

Batch status XXXXXXXXXXXXXX

Product nameProgram name

Batch base temp XX.XXX Deg.C

Batch base pressureBatch equilib press

Batch start timeBatch finish time

X.XXXXX bar abs

X.XXXXX bar abs

XX/XX/XXXX XX:XX:XX

Bch start meter temp XX

XXXXXXXXXXXXXX

Meter Run Data

1 2 3 4

Bch close meter temp XX

Bch start meter pres XX.XXXXX

Bch close meter presBch start meter densBch close meter dens

XX.XXXXX

XXX

XXX

Opening/Closing Cumulative Totals

Bch start IV totalBch close IV totalBch start GV totalBch close GV total

X.XXXXXe+XX

X.XXXXXe+XX

X.XXXXXe+XX

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Bch start ISV totalBch close ISV total

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Batch Totals

Ind vol totalGross vol totalInd std vol total

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X.XXXXXe+XXGross std vol totalMass totalAlarm totalFlowmeter errors

X.XXXXXe+XX

X

X

Deg. C.

Deg. C.

bar abs

bar abs

kg/m3

kg/m3

m3

m3

m3

m3

std m3

std m3

std m3

std m3

kg

kg

m3

m3

std m3

kg

XX/XX/XXXX XX:XX:XX

Batch revision XXX

Previous revision XXX

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std m3

Station Batch TotalsStn Ind vol totalStn gross vol totalStn ind std vol totl

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X.XXXXXe+XXStn gro std vol totlStn mass total X.XXXXXe+XX

Deg.C

bar abs

kg/m3

kg/m3

cSt

m3

m3

std m3

std m3

kg

X.XXX

Quantity Batch TotalsBatch program IDBatch request qtyModified batch qty

Batch av meter tempBatch av meter pressBatch av meter densBatch av base densBatch av degrees API

Batch av MeterFactorBatch av K factorBatch average CTLBatch average CPL

Batch average BS&W

X.XXX

X.XXX

XXXXXXXXXX

X.XXX

************* END OF REPORT **********

X.XXX

Weighted Averages

Batch av kine visc

Batch average CCFBatch av base BS&W

Batch average CSWBatch av oil bdensBatch av oil deg APIBatch av oil water dens

X.XXX

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%

%

kg/m3

kg/m3

Original/duplicate XXXXXXXXXX

Alarm CountsAlarms during batch X

If alarm count is not zero, refer to alarm history log to obtain alarm details.

Note: Net oil/water data not shown due to net calculations not being enabled


Page 18.20 7955 2540 (CH18/AE)

18.2 Retrospective Batch Total Calculations The Flow Computer can re-calculate batch totals by applying updated values of key parameters. It then transmits a report through an appropriately configured communication port.

IMPORTANT It is advisable to first concentrate on the configuration and operation of standard batching (Section 18.1) and archiving (Chapter 9) before using the retrospective calculation options.

18.2.1 OVERVIEW Retrospective calculations can use new user-supplied values of key parameters to re-calculate the batch totals and update data of any archived batch record. An archived batch record is located, updated with new batch totals and re-archived. A revision number is included in the batch record for distinguishing it from the original batch record. This type of update is activated by selecting a ‘Yes’ ‘soft-command’. (See Section 18.2.2 on page 18.21) Alternatively, retrospective calculations can be performed whilst a batch is in progress. In this case, the update can be activated by answering the acceptance prompt following a successful proving session. Batch totals in the current batch (transaction) record are then updated using a new ‘K factor’ or ‘Meter factor’ from the session. No other update parameters are considered. On completion of the batch, the current batch record is archived, as the original, in the normal way. (See Section 18.2.3 on page 18.23) Table 18.9 has a full list of update parameters for supplying new values. Not all update parameters can be applied together. For example, where both the ‘K’ factor and ‘Meter factor’ update parameters have both been edited, the retrospective calculations apply only the most recently edited update parameter. Update parameters are applied in a fixed order as shown in Table 18.10. The optional automatically printed report is an output of the revised batch record. It does not explicitly indicate differences between the original batch record and the revised batch record. Samples can be found in Section 18.1.8, starting on page 18.17. Automatic printing of the batch report can be deactivated by navigating the menu data page with <”Batch auto print”> and then selecting the “Off” option

Table 18.9: Update Parameters of Retrospective Calculation

UPDATE PARAMETER DIRECT IMPACT OF UPDATE CONDITION OF USE FOR UPDATE

Meter factor • Gross Volume flow rate • Newer value than the ‘K Factor’ update value

K factor • Indicated Volume flow rate • Newer value than the ‘MF’ update value

%Water (std vol) * • Net ‘Oil’/’Water’ calculations • Net ‘Oil’/’Water’ calculations must be enabled

Base density * • Degrees API • Newer value than °API update value

Degrees API * • Base density • Newer value than Base density update value

* Not used when performing retrospective calculations whilst a batch is in progress

Table 18.10: Priorities for Applying Update Parameters

ORDER OF APPLICATION UPDATE PARAMETER

1st. <“Meter factor”> or <“K factor”> * 2nd. <”BSW base”>

3rd. <”Base density”> or <”Degrees API”> *

* See Table 18.9 for explanation of parameter choice


7955 2540 (CH18/AE) Page 18.21

18.2.2 USING RETROSPECTIVE CALCULATIONS (ON ARCHIVED BATCH RECORDS) This sub-section is an instructional guide to using retrospective calculations on any archived batch (transaction) record. Instructions assume that a batch has already been completed and archived. It is useful if a serial port is configured for and then connected to an ASCII compatible printer or PC running terminal software. Activation Instructions:

1 Navigate to this menu data page: <”Password”>/<”Enter password”> and then enter the password for the “Engineer” security level. (See Chapter 11 for reference pages on security levels and passwords)

2 Navigate to this menu: <”Batching”>/<”Retro calculations”>/<”Select batch”>

3 Select an archived batch (transaction) record

(a) Nominate a primary search-key type….………….…… {Menu data page: <”Selection type”>}

This is for the auto-location of an archived batch record. Options are either searching the batch archive by ticket number or by archive record number.

(b) Edit a value for the primary search-key…...…………... {Menu data page: <”Batch ID”>}

Identify a sub-set of archived batch records by entering either an existing ticket number or an archived record number, as appropriate for the nominated primary search-key type

(c) Edit a value for the secondary search-key………...….. {Menu data page: <”Batch revision”>}

Reduce the sub-set to a single archived batch record by editing a revision number that is a match for one of the archived batch records. Use zero if requiring the original (unmodified) batch record

Searches are automatically performed after editing the revision number and after editing the ticket/batch record reference number. Failed searches result in an INFO SYSTEM alarm being raised, which can be accepted and cleared from the Historical Alarm Log at any time

4 Verify that the archived batch (transaction) record to be updated has been located

At present, it is necessary to look in the Batch (Transaction) Archive menu system area…

(a) Press the PRINT MENU soft-key

(b) Navigate to this menu: <”Archives”>/<”View / print logs”>/<”Batch log”>/<”View snapshot”>

(c) Browse through the displayed data to see if it is the correct batch record

(d) Return to Step 2 if the batch record has not been located.

5 Program values into the update parameters

(a) Press the MAIN MENU soft-key

(b) Navigate to this menu: <”Batching”>/<”Retro calculations”>/<”Retro values”>

(c) Work through the list of update parameters in Table 18.11.

Ignore the update parameters that are irrelevant to your configuration or are of no interest. Where necessary, use the METER-RUN/STREAM SELECTION soft-key to change metering-point.

Table 18.11: Check-list for Batch Update Parameters

UPDATE PARAMETER MENU DATA (AS DISPLAYED)

‘Meter factor’ or ‘K factor’ <”Meter factor”> or <”K factor”>

% Water (% by Std. Volume) <”BSW base”>

Base density or °API <”Base density”> or <”Degrees API”>

Note: Some localised menu searching is required

Note: Retrospective calculations are not performed unless a minimum of one update parameter

has been edited since Step 2. Initial values for the update parameters are automatically copied from the auto-located archived batch record.


Page 18.22 7955 2540 (CH18/AE)

(Instructions continued…)

6 Select the scope of the retrospective calculation

(a) Locate the menu data page with “Retro calc type” as the descriptor

(b) Select the option with either “All of batch” or “Part of batch”

(c) When the “part of batch” option is selected, navigate to the menu data page with “Retro calc qty”. Edit a quantity to establish the scope of all updates.

7 Activate the retrospective calculation

(a) Locate the menu data page with “Recalculate” as the descriptor

(b) Select the option with “Yes”.

Calculations are performed quickly and are normally completed within one machine cycle. The batch (transaction) record is updated with revised values and then re-archived with the same ticket/archive record reference number and a new revision number.

8 View the modified batch transaction record

Options:

(a) View from Batch (Transaction) Archive menu system area

• Press the PRINT MENU soft-key

• Navigate to: <”Archives”>/<”View / print logs”>/<”Transaction log”>/<”View snapshot”>

• Browse through the displayed data to see if it is the correct batch record (b) View from printed report – see page 18.17 for guidance

(End of Activation Instructions)


7955 2540 (CH18/AE) Page 18.23

18.2.3 USING RETROSPECTIVE CALCULATIONS (ON THE CURRENT BATCH RECORD) This is a guide to activating retrospective calculations on near completion of a successful proving session, whilst a batch is still in progress. Activation Instructions: The following instructions assume that a successful prove session has occurred and a new factor has just been accepted for use in subsequent fiscal flow calculations…

1 Figure 18.11 shows the screen prompt that follows acceptance of a new ‘K factor’ or ‘Meter factor’. This is the opportunity to perform retrospective calculations with the newly accepted flow factor.

(a) Press a blue, lettered soft-key that is alongside the option you require. Use Table 18.12 to decide

which option to select.

Figure 18.11: "Apply to Batch?" Screen

d

b

c

a

Apply to batch?No>

Part>All>

Table 18.12: "Apply to Batch?" Options

Option Purpose of Option

No Do not perform retrospective calculations - continue with Step 3

Part Re-calculate recent part of flow for all current batch total retrospectively - continue with Step 2

All Re-calculate all product flow for each current batch total retrospectively - continue with Step 3

2 Figure 18.12 shows the prompt that appears after selecting the “Part” (‘c’ soft-key) option from Step 1. Specify the ‘part of batch’ as a quantity in the units of measurement displayed. This will be a value in either volumetric or mass units, depending on the configuration for quantity-type batch operations.

(a) Press the ‘c’ soft-key to start the editing process

(b) Edit a value using the numeric keypad

(c) Press the ‘c’ soft-key to confirm the edited value.

Figure 18.12: "Enter batch quantity to adjust" screen

d

b

c

a

Enter batch qty toAdjust: 150.5

3 Continue with the prompts until the menu system re-appears. Retrospective calculations then take place (if activated by Step 1) instantly and are completed within one machine cycle, therefore having a negligible effect on the live batch transaction recording.

(End of Activation Instructions)


Page 18.24 7955 2540 (CH18/AE)

Chapter 19 Flow Computer Basic Language

7955 (CH19/AB) Page 19.1

19. Flow Computer Basic Language (FC-BASIC) This chapter explores the support for creating additional 7955 flow computer features using the built-in programming language called FC-BASIC.

19.1 Introduction 19.1.1 What is FC-Basic?

FC-BASIC is the 7955 flow computer version of the traditional computer programming language known as BASIC (Basic All-purpose Symbolic Instruction Code). Although not grabbing headlines in recent years, those who owned microcomputers in the 1980’s will still fondly remember BASIC. Functional Overview Lines of FC-BASIC language are typically edited on a PC (or similar system) to form a program script. If using a PC running Windows, you may wish to use the Notepad program as the editor. Once you have finished editing, save the program script as a text file. The next step is to transfer the program script (text file), to the flow computer through an RS-232 serial cable, interconnecting PC serial port and 7955 serial port. If using a PC running Windows, you may wish to use Terminal (Windows 3.1) or Hyperterm for carrying out the transfer. No more than one program script can be stored in the 7955. The length of script is limited by memory availability. You may also use the same PC application to enter FC-BASIC commands directly: LIST, DELETE and VERIFY. For information on these commands, turn to page 19.2. Once transferred to the flow computer, the FC-BASIC script can be run. Assuming there are no errors, it executes repeatedly once every machine cycle. Each execution must complete within 2½ times the target cycle time. Otherwise, the flow computer forces the FC-Basic program to terminate.

19.1.2 What can FC-BASIC be used for?

Typical uses of FC-BASIC are: • The generation of text-based logs at pre-determined times, weekly, monthly, or intervals of days. • Automatic triggering of a prove-session after a pre-determined period, after a pre-set volume of flow, or

if the fluid viscosity has changed. • Automatic opening or closing of metering-runs (streams) depending on station flow rate. • Grab sampler handling. An alarm can be raised when the sample is 90% full. • Changing engineering units.

Note: Before running the FC-BASIC script, you will need to be at PROGRAMMER security level.

Note: It is assumed that the readership has a working knowledge of a Windows-based PC, is reasonably familiar with interconnecting the PC and 7955 Flow Computer and has some experience with computer programming.


Page 19.2 7955 (CH19/AB)

19.1.3 What needs to be configured on the 7955?

Very little needs to be configured. Apart from basic communication parameters, there are a few FC-BASIC simple set-up parameters: FC-BASIC 1. Ensure you at PROGRAMMER security level.

2. Navigate to this menu: <”Configure”>/<”FC Basic”> to find these parameters:

<FCBasic control> A menu ‘soft-command’ to toggle between enabling program scripts to run and preventing program scripts from running.

<FC Basic Timeout> Optional. This defines the maximum period allowed before the flow

computer must intervene and terminate a running program script.

<FCBasic end-of-line> Toggle between “Carriage-return” or “Line-feed” to determine how FC-BASIC distinguishes the end of a line in a program script. (Whenever using Hyperterm, as the ‘text file’ transfer application, it is best to select ‘line-feed’ options on both PC and 7955 Flow Computer.)

SERIAL PORTS 1. One 7955 serial port connection will be required for the issuing direct commands (e.g. LIST) and the

transfer of FC-BASIC program script (text file) from an external system (e.g. PC, MAC, etc.) to the 7955. Basic communication parameters are as guided in Chapter 7, for RS-232 set-up. The exception is <PORT OWNER>, where you must select “FC Basic”.

2. To view outputs from the FC-Basic program, it is necessary to set-up a serial port for connection to an

ASCII compatible output device, such as a printer or a PC acting as a terminal. (See Chapter 7.)

19.2 EDITOR COMMANDS The following commands can be issued to the serial port configured for FC-BASIC. LIST Lists all lines of the FC-BASIC script currently stored in the 7955. DELETE Deletes the entire FC-BASIC script currently stored in the 7955. VERIFY Checks that the FC-BASIC script has no syntax errors. Checks if there are references to non-

existent lines in the script. Allocates memory space for DIM declared variables and initialises their value to 0. Processes ONTIMER declarations.

All errors are output. Any error will cause the program not to run. Otherwise, if the program is okay then it is flagged as ready and will be executed during the next machine cycle.


7955 (CH19/AB) Page 19.3

19.3 COMMAND DIRECTORY This section provides information on the use of FC-BASIC commands. All FC-BASIC statement lines are preceded by a line number, which identifies the position within the program script. Line numbers can range from 1 to 9999 inclusive.

19.3.1 STATEMENTS

REM (REMark) Purpose: It allows a script to be documented. All characters on the line, beyond the REM command,

have no effect on the FC-BASIC program. Example: 10 REM *** This is a REMark statement ***

IF, THEN, [ELSE] ENDIF Purpose: IF is always followed by a Boolean expression. When the expression evaluates to TRUE,

the program script execution continues with the next statement line following the THEN. Otherwise, the expression evaluates to FALSE and program script execution continues with the next statement line following the ELSE or the ENDIF where there is no ELSE.

Example: 10 A = 1 20 IF A <> 2 20 A = A + 1 30 ELSE 40 A = A + 2 50 ENDIF : 70 B = 1 70 IF B <> 2 80 B = B + 1 90 ENDIF

GOTO (GO TO) Purpose: Transfers ‘interpret and execute’ control directly to another line in the same program script. Example: 10 GOTO 50 20 REM *** LINE 20 IS NEVER REACHED *** : 50 REM *** JUMPED HERE FROM LINE 10 ***

GOSUB, RETURN Purpose: GOSUB temporarily transfers program control directly to another line in the same program

script. When the RETURN is encountered, program control reverts back to the next statement line following the original GOSUB.

Note: This FC-BASIC statement can be nested, and recursive, limited only by memory availability. Example: 10 GOSUB 50 20 REM *** LINE 20 IS REACHED *** : 50 REM *** TEMPORARY JUMP HERE FROM LINE 10 *** 60 A = A + 1


Page 19.4 7955 (CH19/AB)

70 B = B + 1 80 RETURN 90 REM *** NEVER REACH LINE 90 SINCE CONTROL ALWAYS 100 REM *** RETURNS TO LINE 20

FOR X = Y TO Z, NEXT [STEP W] Purpose: Executes a loop of statement(s) for a delimited number of times. The loop always executes

at least one.

The variable X, an integer value, is initialised with the value of Y, which can be a constant or a variable. W is optional and may be positive or negative. If missing, the value 1 is assumed. When the NEXT is reached, W is added to X. The X is compared to Y. If W is positive, the loop will execute again as long as Z is greater than X. Conversely, when W is negative, the loop will execute again as long as Z is less than X. The loop stops when X is equal to or greater than Z. On exiting the loop, X contains the value last used for the comparison.

Example: 10 B = 0 20 FOR A = 1 TO 10 30 B = B + A 40 NEXT

WHILE, WEND Purpose: Executes a loop of statement(s) until a Boolean expression evaluates to FALSE. The loop

does not execute unless the Boolean expression initially evaluates to TRUE.

The WHILE is always followed by a Boolean expression. Statement lines between WHILE and WEND will be executed as long as the expression evaluates to TRUE. When the expression evaluates to false, ‘interpret and execute’ control continues with the next statement line following WEND.

Example: 10 A = 1 10 WHILE A < 10 20 A = A +1 30 WEND

STOP Purpose: Stops the program script execution at this line.

Example: 10 STOP

TIME Purpose: Obtains the seconds value from an internal clock timer. The value can be used in

calculations within the program script. It is useful for tracking the elapsed time between loops. TIME will return a 6 element array containing 0=seconds, 1=minutes, 2=hours, 3=day, 4= month and 5=year.

See also: TIMER and ONTIMER


7955 (CH19/AB) Page 19.5

TIMER(1...8) Purpose: There are up to 8 countdown timers available. They can be assigned a period of seconds in

the range of 0 to (232 –1)/1000. The timers run backwards, decreasing by each cycle. On reaching zero, ONTIMER GOSUB is invoked.

To cancel a timer, set the period to 0 (zero seconds).

ONTIMER(1...8), GOSUB Purpose: When a particular timer reaches 0 (zero seconds), program control is transferred directly to

another line in the script. As with all GOSUB statements, there must be a RETURN. Note: It is only ever invoked when the particular timer reaches 0, irrespective of where it is

positioned in the script. See also: TIMER Example: 10 ONTIMER(1) GOSUB 100 20 REM *** CONTROL RETURNES HERE FROM LINE 120 *** : 100 REM *** JUMPS HERE ONLY WHEN TIMER(1) REACHES ZERO *** 110 A = A + 1 120 RETURN 130 REM *** NEVER GETS HERE SINCE CONTROL RETURNS TO LINE 20 ***

DIM (DIMensional array) Purpose: Declares a variable as a one-dimensional (flat) array of a specified size. A variable array

can store values of floating-point numbers or integers in particular positions (spaces). Note: Array declarations do not directly affect program control or the way a script is executed. Example: 10 DIM turbine_array(2) as float : 40 REM Set-up turbine array with values in positions 0, 1 and 2 50 turbine_array(0) = 0.5 60 turbine_array(1) = 5.0 70 turbine_array(2) = 2.2

PRINT Purpose: A means to output simply formatted data through a serial port that has been configured for

connection to an ASCII compatible device, such as a printer. Two special formatting functions, SPC and TAB, as provide for use in PRINT statements. SPC(n) is used to insert space characters in the output, where n is the number of spaces

required. TAB(N) is used to position the insertion point to an absolute column number, where n is the

column number. Use TAB with no argument to position the insertion point at the beginning of the next print zone.

Note: If a ‘;’ is used as a separator, the next print item is output in the next print zone. Examples: 10 PRINT “THIS IS A PRINT STATEMENT”

: 40 FOR A = 1 TO 5


Page 19.6 7955 (CH19/AB)

50 PRINT “A = ”;A 60 NEXT

19.3.2 BOOLEAN EXPRESSIONS FALSE = 0 A value of ZERO is equal to logical FALSE TRUE<>FALSE True is any value that is not equivalent to FALSE

19.3.3 LOGICAL AND BITWISE OPERATORS NOT AND OR XOR

19.3.4 RELATIONAL OPERATORS <> > < <= >=

19.3.5 ARITHMETIC OPERATORS + - * / ^ MOD DIV

19.3.6 ARITHMETIC FUNCTIONS ABS ACOS ASIN ATAN BSGN COS EXP INT LN POW SIN SQRT TAN TIME PEEK POKE GETSTATUS SETSTATUS


7955 (CH19/AB) Page 19.7

19.3.7 PRE-DEFINED ARRAYS

LOC(XXX) 7955 database variable access.

AIN(X) Analogue input access

AOUT(X) Analogue output access

DIN(X) Digital (status) input access

DOUT(X) Digital (status) output access

VIN (X) Valve status access

VOUT(X) Valve command access

TIMER(X) See TIMER entry in earlier section

19.3.8 PRE-DEFINED CONSTANTS

TRUE -1 (NOT 0 is –1)

FALSE 0

LIVE 0

SET 1

FAIL 2

FB 3

19.3.9 VARIABLE TYPES

Float 64-bit floating point number

Integer Signed 32-bit number

Array Each element a float

19.3.10 7955 DATABASE ACCESS

PEEK(X) Read last data of location X

POKE(X) Write data to location X

GETSTATUS(X) Read status of location X. Returns a numeric value, equal to one of the pre-defined constants: LIVE, SET, FAIL or FB

SETSTATUS(X, N) Write status of location X. The N is a numeric value, equal to one of the pre-defined constants: LIVE, SET, FAIL or FB


Page 19.8 7955 (CH19/AB)

19.4 SAMPLE FC-BASIC SCRIPTS This section provides a few samples that can be adapted to suit other applications.

FC-BASIC Script 19.1: Printed Report

1000 REM ************************************************************** 1010 REM * Program Start. * 1020 REM * * 1030 REM * This program prints a report every 10 seconds. * 1040 REM ************************************************************** 1050 REM 1060 Seconds = time(0) 1070 ElapsedTime = Seconds - LastSeconds 1080 IF ElapsedTime < 0 THEN ElapsedTime = ElapsedTime + 60 1090 REM 1100 IF ElapsedTime >= 10 THEN GOTO 1110 ELSE GOTO 1150 1110 GOSUB 5000 1120 LastSeconds = Seconds 1130 REM 1140 REM 1150 STOP 1180 REM 5000 REM ************************************************************** 5010 REM * PrintReport. * 5020 REM * * 5030 REM * This subroutine prints a report. * 5040 REM ************************************************************** 5050 REM 5060 REM Set-Up Location IDs 5070 REM ------------------- 5080 LocMassTotal = 1786 5090 LocBaseVolTotal = 1762 5100 REM 5110 REM Get Values From Database 5120 REM ------------------------ 5130 MassTotal = peek (LocMassTotal) 5140 BaseVolTotal = peek (LocBaseVolTotal) 5150 REM 5160 REM Print The Report 5170 REM ---------------- 5200 REM PRINT time (2); ":"; time (1); ":"; time (0) 5210 PRINT "Mass Total = "; MassTotal 5220 PRINT "BaseVol Total = "; BaseVolTotal 5230 PRINT " " 5240 REM 5250 REM 5260 return


7955 (CH19/AB) Page 19.9

FC-BASIC Script 19.2: Grab Sampler

1000 IF FirstProgCycle = 0 THEN GOSUB 2000 ELSE GOTO 1010 1010 IF GrabFlag = 0 THEN GOTO 1020 ELSE GOTO 1100 1020 Total = peek(1762) 1030 Inc = Total - LastTotal 1040 IF Inc > 16 THEN GOTO 1050 ELSE GOTO 1200 1050 dout(10) = 1 1060 GrabFlag = 1 1070 LastTotal = Total 1080 GOTO 1200 1090 REM 1100 GrabCycleCount = GrabCycleCount + 1 1110 IF GrabCycleCount > 3 THEN GOTO 1120 ELSE GOTO 1200 1120 dout(10) = 0 1130 GrabFlag = 0 1140 GrabCycleCount = 0 1200 STOP 2000 dout(10) = 0 2010 LastTotal = peek(1762) 2020 FirstProgCycle = 1 2030 RETURN


Page 19.10 7955 (CH19/AB)

Appendix A Glossary

7955 (Appx-A/AF) Page A.1

Appendix A Glossary

A ADC See Analogue to digital converter

Address A number which uniquely identifies a location.

Alarm An indicator which shows when a failure has occurred. Alarms are classified as System, Input or Limit.

API American Petroleum Institute

Analogue input An input where information is received in analogue form.

Analogue output An output from which information is transmitted in analogue form.

Analogue to digital converter A circuit that converts analogue voltages or currents into digital (usually binary) numbers which can then be processed by computers. The digital signal gives the amplitude of the analogue signal at a particular instant. See also Digital to analogue converter.

AUI Short for Attachment Unit Interface, the portion of the Ethernet standard that specifies how a cable is to be connected to a transceiver that plugs into a 15-pin socket

B Bar A unit of pressure. 1 bar = 105 Nm2.

Base condition Base or Standard Conditions give the volume which would have been transferred if the temperature were at a pre-defined figure. The actual values for base temperature and pressure vary from country to country.

Base density Density of a fluid measured under base conditions.

British Thermal Unit The energy required to raise the temperature of one pound of water through one degree Fahrenheit.

BTU See British Thermal Unit.

C Calibrate To assess the performance of an item of equipment against that of

another one whose accuracy is known.

Appendix A Glossary

Page A.2 7955 (Appx-A/AF)

Calibration certificate Each transducer is calibrated before it leaves the factory. The details (together with the transducer’s serial number) are recorded on a Calibration Certificate.

Calibration constant Among the information given on the calibration certificate are some constants (unique to that transducer) which compare the transducer’s actual performance against a standard. The signal converter must know these constants before it can calculate accurate results.

The constants are designated: K0, K1, K2, and so on.

Calorific value The energy content of a substance (usually a gas).

Chassis earth In a large installation where the chassis and instrumentation are earthed separately, this is the “dirty” earth to which instrument chassis are connected.

Checksum In data transmission, a checksum is a number which is added to a string of data and whose value is related to that data. It is used to check that the data has been transmitted accurately.

Connector The part of a cable that plugs into a port or interface to connect one device to another. Most connectors are either male (containing one or more exposed pins) or female (containing holes in which the male connector can be inserted).

Configuration 1. The setting up of an instrument (by entering data, setting fallback values, setting alarms, and so on) so that it works according to your requirements.

2. The method by which transducers and other inputs and outputs are physically connected to the 7955

Conventional pipe prover This has a volume between detectors that permits a minimum accumulation of 10,000 direct (unaltered) pulses from the meter under test.

Covimat A rotational viscometer.

Crystal factor A multiplying factor which accounts for the difference between the actual frequency of a particular crystal and its theoretical frequency.

CV See Calorific value

D DAC See Digital to analogue converter

Damping Suppressing the oscillations in a vibrating body or medium.

Degree API Used in the petroleum industry to describe the density of petroleum products. A degree API is given by:

141.5/(SG at 60oF) - 131.5

Values lie within the range -1 to +101, the larger the number the lighter the oil.

Appendix A Glossary


Degree Baume A unit on an arbitrary scale which can be converted into actual SG values. Used when describing the sugar content of aqueous solutions.

Degree Brix A unit on an arbitrary scale which can be converted into actual SG values. Used when describing the sugar content of aqueous solutions.

Density The measured density of the fluid in a pipeline.

Differential pressure The difference in pressure at two points in a pipeline.

Digital to analogue converter A circuit that converts digital signals into analogue equivalents. See also Analogue to digital converter.

Download To send data or programs to another (usually subsidiary) instrument. (Opposite of Upload).

DP See Differential pressure

E EMC Electro-Magnetic Compatibility

Event A change in the system operation. Events may be caused by the user (such as setting a parameter or changing the security) or by alarms (if, for example, a fallback is invoked when the system fails).

External connection A generic term which covers: inputs, outputs, power supplies and serial communications; in short, anything connected to the 7955.

F Fallback mode A description of the system when it is using a Fallback value.

Fallback value A value used as a temporary substitute for a parameter when a live input which is used to calculate the parameter fails.

Flow computer

An instrument which monitors flow rates and densities of gases and liquids. It does this by communicating with transmitters such as pressure, temperature, level, flow, density and analytical instruments. These measurements are then corrected for temperature, pressure and velocity of sound.

FS Full scale.

Full composition The composition of a gas used in calculating energy and compressibility.

Appendix A Glossary


H Hazardous area An area where there is a risk of fire or explosion.

Health check a check that all inputs and devices connected to the 7955 are operating normally.

Hg The chemical symbol for the element Mercury.

Historical log A log of every alarm received by the 7955.

Hub A common connection point for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets.

A passive hub serves simply as a conduit for the data, enabling it to go from one device (or segment) to another. So-called intelligent hubs include additional features that enables an administrator to monitor the traffic passing through the hub and to configure each port in the hub. Intelligent hubs are also called manageable hubs.

I Instrumentation earth In a large installation where the instrumentation and chassis are

earthed separately, this is the “clean” earth to which the instrumentation is connected.

Interrogate To ask another part of a system to supply information.

J J See Joule.

Joule The unit of work. 1J = 1N/m2.

Jumper A metal bridge that closes an electrical circuit. Typically, a jumper consists of a plastic plug that fits over a pair of protruding pins. Jumpers are sometimes used to configure add-on (option) boards. By placing a jumper plug over a different set of pins, you can change a board's parameters.

K K-factor The K-factor relates the output from a flow meter to a specific set of

units. For volume output meters such as turbines, it is often quoted as pulses per meter cubed.

Kinematic viscosity The ratio of the dynamic viscosity of a fluid to its density.

Appendix A Glossary


L LED See Light-emitting diode.

Light-emitting diode A diode which light up when current flows through it. LED’s are usually used as indicator lights on instruments.

Limit Limits are upper and lower values between which a measured parameter is expected to be. If the parameter is outside these limits, it can trigger an alarm if you have set the system to do so.

Live A value is live if it can be altered automatically as a result of some internal calculation or transducer input. (See also: Set.)

Location An area of computer memory where data is stored. Information can be written to it from the keyboard, a remote computer, or automatically by the sensors.

Location ID A number which uniquely identifies a location.

M Mass flow rate The rate at which a given mass of fluid flows through a transducer.

MAU Short for Media Access Unit, an Ethernet transceiver

MODBUS/TCP MODBUS/TCP is a variant of the MODBUS family of simple, vendor-neutral communication protocols intended for supervision and control of automation equipment. Specifically, it covers the use of MODBUS messaging in an ‘Intranet’ or ‘Internet’ environment using the TCP/IP protocols. The most common use of the protocols at this time are for Ethernet attachment of PLC’s, I/O modules, and ‘gateways’ to other simple field buses or I/O networks.

Mode The operational state of the instrument.

Monitor To keep a constant check on the status of a system or process.

Multiples of numbers T M m

tera mega milli

1012 106 10-3

G k μ

giga kilo micro

109 103 10-6

Multiview A user-defined display which can show up to four lines of information of your choice. Typically, each line comprises text (such as a parameter name) and a value for the parameter.

P Pa See Pascal.

Pascal The unit of force. 1 Pa = 1N/m2

Appendix A Glossary


Percent mass The percentage that the mass of a substance has compared to the total mass for a mixture of substances of which it is a part.

Periodic time The duration of one cycle of a wave-form, equal to the inverse of the frequency.

Platinum resistance thermometer A highly-accurate thermometer, based around a coil of very pure platinum wire, which is extremely stable over time. It can be used instead of an analogue input to the signal converter or flow computer.

POST See Power-on self test.

Power-on self test A standard routine which an item of equipment goes through when it is powered up to make sure that it is operating correctly. The progress of the test is usually shown on the instrument display.

Protect ground Another name for Chassis earth.

PRT See Platinum resistance thermometer.

Pressure The measured pressure of the fluid in the pipeline.

Primary variable A variable (such as time or distance) which is directly measured.

psi Pounds per square inch. Imperial units of pressure.

Pulse output An output of single pulses, sent to equipment such as pulse summators or electro-mechanical totalizers.

PV See Primary variable

R Radio frequency interference Interference from sources which transmit at radio frequencies; that is,

frequencies in the range of about 100kHz to about 300GHz.

Reynolds number A dimensionless constant given by μ

ρν

vlvl ==Re

Where: μ = fluid viscosity

l = length ν = kinematic viscosity ρ = density

RFI See Radio frequency interference

RS-232 An international standard for serial data transmission. It specifies voltage levels, timing and control.

Appendix A Glossary


S Saybolt viscosity A viscosity measured using methods developed by the Saybolt

company. It is obtained by timing how long the fluid takes to flow out of a cup through a hole of known size. The viscosity is expressed in units of time.

Security code A code or password which a user must key in before being allowed access to all or part of a system.

Sensor Another name for a transducer.

Set A value is SET if it is keyed in by the user and does not change unless the user changes it. (See also: Live.)

Set-up routine A procedure for setting up or configuring a system.

SG See Specific gravity

Signal converter A device which converts one signal into another. Its main use is in quality measurement systems such as brewing where the output is used by a control or monitoring system.

Specific gravity The mass per unit volume of a fluid.

Standard condition See Base condition

Status The condition of part of a system; for example, whether it is on, off, and so on.

Status display A display which summarises the contents of the Historical log and gives an indication of the current status of the system.

T TCP/IP Abbreviation for Transmission Control Protocol/Internet Protocol, the

suite of communications protocols used to connect hosts on the Internet. TCP/IP uses several protocols, the two main ones being TCP and IP. TCP/IP is built into the UNIX operating system and is used by the Internet, making it the de facto standard for transmitting data over networks. Even network operating systems that have their own protocols, such as Netware, also support TCP/IP.

Temperature The measured temperature of the fluid in the pipeline.

Temperature correction Transducers are typically designed to work at 20°C. A correction must be applied when working at other temperatures.

Text descriptor Text which you can enter into the signal converter. Typically, this is a parameter name when you configure Multiview.

Therm Unit of heat. 1 therm is the heat required to raise 1000 pounds of water through 100°F.

Appendix A Glossary


Transducer A device which converts a physical quantity (such as temperature or pressure) to a voltage or some other electrical quantity that can be measured and analysed.

U Upload To receive data or programs from another instrument. (Opposite of

Download).

V Viscosity In a liquid, the resistance to that force which tends to make the liquid

flow.

Volume flow rate The rate at which a given volume of fluid flows through the system.

VOS Velocity of Sound

W Wizard One of the “standard” configurations whch you can select instead of

configuring the 7955 from scratch. You can edit the resulting configuration to meet your requirements.

Wobbe index A measure of the amount of heat released by a gas burner of constant orifice. It indicates the quality of the gas and is given by the expression

21−

ρV

Where:

V = the gross calorific value in BTU per cubic foot at STP

ρ = specific gravity.

Appendix B Blank wiring schedule

7955 (APPX-B /AC) Page B.1



Page B.2 7955 (APPX-B /AC)


7955 (APPX-B /AC) Page B.3

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Page B.4 7955 (APPX-B /AC)

Appendix C Technical data for the 7955

7955 (APPX-C/AE) Page C.1


C.1 What this Appendix contains Ordering information – understanding model codes

List of different types of external connections you can make to 7955

Technical Specification

Rear panel pin identity tables

Internal earthing arrangements

C.2 External connections You can make the following types of external connections to the 7955:

INPUTS Analogue Inputs from devices which monitor continuously changing parameters and transmit analogue signals. These include:

PRTs (PT100)

temperature transducers (0/4-20mA)

pressure transducers (0/4-20mA)

differential pressure transducers (0/4-20mA)

viscosity transducers (0/4-20mA)

calorimeters (0/4-20mA)

Pulse Inputs from devices which transmit information as pulses. For example, a turbine (or positive displacement) flowmeter.

Time period (Dens./Visc.)

Inputs from devices where the frequency of the transmitted signal is related to the parameter being measured. These include:

density transducers (e.g. 7835 or 7826)

base density transducers

viscosity transducers (e.g. 7827).

Status One of two levels, to show the state of some part of the system, such as whether a valve is open or closed.

OUTPUTS Analogue Outputs from the signal converter to those devices (such as chart recorders) which require analogue outputs (0/4-20mA).

Pulse For equipment such as pulse summators or electro-mechanical totalizers (open collector).

Status Outputs to equipment whose status is to be changed as, for example, an output which opens or closes a valve (open drain).


Page C.2 7955 (APPX-C/AE)

Serial Communications

For receiving and sending information to other devices linked to 7955. These include:

Printers

Host computers

Master or slave 7955’s, Chromatographs, etc.

Power supplies Inputs d.c. only

Outputs d.c. only. These provide power within the 7955 and to some other external devices such as transducers.

Isolation notes

The isolation between the enclosure and all DC power inputs, signal inputs and signal outputs is: 50VDC continuously OR 125VDC for less than 15 seconds.

Consequently, isolation between any two signal lines and any DC power line is:

100VDC continuously OR 250VDC for less than 15 seconds.

C.3 Maximum number of external connections The table below lists the maximum number of external connections which you can make to a single 7955 Flow Computer.

Type of connection Maximum number

Standard Additional with board 79550506

Additional with board 79550507

Additional with board

79550508

Additional with board 79550509

Inputs

Analogue 16 0 0 0 0

HART 0 0 4 0 0

Pulse 5 0 0 0 0

Time period 4 0 0 0 0

Status 24 0 0 2 2

Outputs

Analogue 4 4 0 0 0

Pulse 5 0 0 0 0

Status 25 0 0 0 0

Serial Comms. ports

RS232 1 0 0 0 0

RS232/485 2 0 0 2 2

10Mb/s Ethernet ports 0 0 0 0 1

Note: Option board kit numbers are referred to without the “050” e.g. 79556



C.4 Specification

General Environmental Operating temperature 0 to +50°C (-4 to +158°F)

Storage temperature -20 to +70°C (-32 to 122°F)

Relative humidity Up to 90% non-condensing

Bump BS 2011 test Eb

Vibration Tested to IEC publication 68-2-6, Part II, frequency 10 to 150Hz, maximum acceleration 20m/s2

EMC Emissions and Immunity EN 61326-1998 (industrial locations)

Electrical Safety To BS EN 61010 standards

Enclosure IP50 from the front panel, only when mounted.

Dimensions Height 101mm (4”)

(of enclosure) Width 197mm (7¾”)

Depth 355mm (14”) *

* Also allow room for rear panel connector and adapter protrusions

Weight 3.5kg

External connections Type D-type rear panel comprising of:

3 off 50-way D-types for all connections except communications and power.

1 off 9-way, 1 off 15-way and 1 off 25-way D-type connectors for serial communications.

4-way Klippon connector for power.

Options None



Inputs Analogue 4-20mA input accuracy without HART

active ±0.008% of full scale at 25oC ± 0.001%/oC

4-20mA inputs (13, 14, 15 & 16) accuracy with HART active

±0.1% of full scale at 25oC ± 0.001%/oC

4-20mA input resolution Better than 4 parts per million

PT100 accuracy (-50 to +200 oC) ±0.05ºC ±0.01oC/oC

PT100 resolution Better than 0.02ºC

PT100 energisation <1mA average (Meets BS1904 & IEC751, <1mW in the PT100)

Long term drift <20ppm per 1000 hours for first 1000 hours, subsequently far less

Quantity 16 off : First four are selectable as PT100, 0-20mA or 4-20mA. Remainder are selectable as 0-20mA or 4-20mA.

Scan time 60ms per channel

Options None

Pulse Frequency range DC to 5kHz (dual pulse train) or 10kHz (single pulse

train); minimum pulse width 125s

Input trigger level 0.5V (1.2V p-p)

Quantity 5 off single or dual-pulse turbine

Options None

Time period Range 100s to 5000s

Accuracy ±30nS

Resolution 2ns at 1kHz for 1-second sample

Input trigger level 0.5V (1.2V p-p)

Quantity 4 off

Options None

Status Type Polled

Trigger voltage 5V to 24V opto-isolated

Poll period Maximum 250ms

Quantity 24 off

Options When option board 79550508 is fitted: additional 2 off inputs

When option board 79550509 is fitted: * additional 2 off inputs

* Also enables a 10 BaseT Ethernet Port



Outputs

Analogue Base board device accuracy (12-bit) ±0.075% of full scale (24mA) +/- 0.00075%/ oC

Base board device resolution 1 part in 3500

Long term drift <20ppm per 1000 hours for first 1000 hours, subsequently far less

Quantity 4 off

Update time 0.1s minimum, software dependent

Options Option board 79550506 for an extra 4 channels

Special Notices 1. The maximum load impedance that the analogue outputs can drive is 1K Ohms. This must include any barrier impedance and the load itself.

2. Analogue outputs are “Active Loops”. (Active loops are powered by the device providing the current output. “Passive loops” are powered externally, usually by the device receiving the current)

Pulse Output type Open-collector Darlington drivers

Maximum current 200mA per output at 24V with maximum 50% duty

Maximum frequency 10Hz

Quantity 5 off

Options None

Status Type Output 1 uses a relay (24V DC/30V AC @ 250mA maximum),

Others use open drain (100mA each at 24V)

Update rate Software controlled

Quantity 25 off

Options None

Prover interface

Type Fleeting contact ball detectors (opto-isolated)

Minimum pulse width for detection 10mS

Quantity 2 off (can also be used as extra status inputs)

Options None

Communications

Serial communications Port 1 Physical layer RS232 full duplex

Max. baud rate 19K2

Handshake XON/XOFF

Port 2 Physical layer RS232 full duplex or RS485 half duplex

Max. baud rate 19K2

Handshake XON/XOFF and/or RTS/CTS



Port 3 Physical layer RS232 full duplex or RS485 half duplex

Max. baud rate 19K2

Handshake XON/XOFF and/or RTS/CTS

Options When option board 79550508 is fitted: additional 2 off RS232/RS485 channels When option board 79550509 is fitted: additional 2 off RS232/RS485 channels

1 off 10 BaseT (10Mbit/s) Ethernet Port

SMART transmitter communications

Number of loops None on standard unit

Options When option board 79550507 is fitted: 4 loops of Rosemount HART using analogue

inputs 13, 14, 15 and 16

Hardware facilities

Keyboard interface Number of keys 30

Key scan time 2ms

Debounce 14ms

Options None

Display Number of lines 4

Characters per line 20

Backlight LED, continuously powered

Contrast software selectable, temperature compensated

Options None

Real-time clock Accuracy Better than 1 second per day

Power Replaceable Lithium button cell

Options None

Battery monitor Type ADC, indicates battery condition

Options None

Alarm annunciation Quantity 3 (one each for Input, System or Limit alarms)

Type Red LED

Operation Flash indicates new alarm condition. Steady indicates accepted alarm.

Options None



Security Mechanisms 1. Switch located on front panel 2. Software code

Indicator Bi-colour LED on the front panel: 1. RED: Not secured 2. GREEN: Secured 3. ORANGE: Part-secured

Options None

Memory Program storage 3 Mbyte FLASH, field programmable

Data storage 768k Bytes of battery-backed. Battery life is typically 2 years if instrument is un-powered or 5 years if powered.

64k Bytes of non-volatile store for calibration data

Options None

Co-processor

Type 80-bit floating point maths co-processor

Options None

Power Supplies

Input 21V-30V dc. 35W maximum. 2A worst-case start-up current

Output General instrumentation energisation

1 x 24V nominal at 800mA

Turbine energisation Switchable voltages of 8V or 16V, current limited to 120mA

DAC energisation Isolated 25V output at 200mA

Options None



C.5 Connections Table C.1 is a reference for the pins of connectors on the rear panel (Figure C.1 and Figure C.2). You should note that some connections are not fitted as standard and require an option board to be fitted first.

Figure C.1: D-type rear panel of 7955 Flow Computer

Figure C.2: Types of connector on the 7955 Flow Computer



Table C.1: Rear Panel Pin Designations

Pin SK1 SK2 SK3 SK4 SK5 SK6 PL1

1 Status o/p 12 Status i/p 1 Alarm common Ethernet 0V Comm 5 rx/tx + Ground

2 Status o/p 13 Status i/p 2 Alarm NC Ethernet cd + Comm 5 rx Comm 1 tx Ground

3 Status o/p 14 Status i/p 27 Alarm NO Ethernet tx + Comm 5 rts Comm 1 rx Supply -

4 Status o/p 15 Status i/p 28 Turbine power + Ethernet 0V Comm 4 rx/tx + Supply +

5 Status o/p com Status i/p 3 Analog i/p 15+ Ethernet rx + Comm 4 rx Comm 0V

6 Pulse o/p com Status i/p 4 Analog. i/p 14 + Ethernet 0V Comm 4 rts


8 Turbine Sig. 9 + Status i/p 6 Analog i/p 11 + Ethernet 0V Comm 3 rx/tx +

9 Turbine Sig. 9 - Status i/p 7 Analog. i/p 9 + Ethernet cd - Comm 3 rx

10 Turbine Sig. 2 + Status i/p 8 Analog. i/p 8 + Ethernet tx - Comm 3 rts

11 Turbine Sig. 2 - Status i/p 9 Analog. i/p 6 + Ethernet 0V Comm 2 rx/tx +

12 Turbine Sig. 5 + Status o/p 2 Analog. i/p 5 + Ethernet rx - Comm 2 rx

13 Turbine Sig. 5 - Status o/p 3 PRT 4 power + + 12V Comm 2 rts

14 Turbine Sig. 8 - Status o/p com PRT 3 signal + Ethernet 0V Comm 5 rx/tx -



















33 Density Sig. 4 + Analog. o/p 5 PRT 1 Signal -



36 Status o/p 23 Status i/p 20 +24V Den/Ana./Turb












48 Density Sig. 2 + Analog. o/p 6 PRT 2 Power -

49 Density Sig. 2 - Analog. o/p 7 PRT 1 Power +




C.6 Earthing In addition to earthing the chassis, (described in Chapter 4), you may have to make extra earth connections in some cases, depending on the installation requirements.

The types of connection can be split into three groups, each of which has different earthing requirements. The groups are:

Group 1 (non-isolated power supply): Serial RS232/RS485 ports Ethernet port Pulse outputs Status outputs

Group 2 (isolated power supply): Status inputs Analogue outputs

Group 3 (isolated power supply): Analogue inputs Frequency inputs

Figure C.3 on page C.11 shows you how to earth the external connections.



Figure C.3: Earthing arrangements for the 7955 (D-type connectors)

Analogue o/p Common

E E 0v +25VDC Power

Pulse Output Common

Status Output Common

0V Serial PortProtect Ground

Protect Ground

Protect Ground

Protect Ground

Protect Ground

Protect Ground

0V Serial Port

Pin 25

0V Ethernet

Pin 1

SK2

SK3

Group 1(SK1, SK2/14, SK4, SK5

and SK6)

Chassis andinstrumentation are

earthed together unlessyou cut Link 1

InternalIsolatedSupply0V Analogue Inputs

0V Density Inputs

Group 2(SK2/34, SK2/35 )

No earthing isrequired for Status

Inputs

Status Input Common (Opto-isolated)

SK1

Status Output Common

Pin 1

Pin 50

Pin 50

Pin 1

Pin 1 0V Turbine/Density/Analogue Inputs

Pin 50

Pin 15

0V Ethernet

Pin 1

SK4

SK5

SK6

Link

Pin 9

Pin 1

PL1ChassisEarth Earth

stud

Group 3(SK3)

Connect externalearths asrequired.



Earthing requirements for group 1 connections only

In general, the earthing arrangements are different for large and small installations. (A small installation may possibly consist of just one instrument.)

If the 7955 is part of a large installation with separate earths for chassis and instrumentation:

In this case you may (depending on the overall system requirements) earth the 7955 chassis and instrumentation separately by cutting the link on the connector board.

If the 7955 is on its own or in a small installation with one common earth for chassis and instrumentation:

In this case you must leave the link intact so that the chassis and instrumentation are earthed to the same point.

Figure C.4: Where to find the link on the connector board

LinkProcessorBoard

MotherBoard

RearPanel

Top ofinstrumentcase

SocketSK1




The status inputs do not have to be earthed because the circuitry contains only opto-electrical components. However, they can be externally earthed if an installation requires it.


These depend on what sort of installation you have and the environment in which it operates. You therefore have to decide what earthing arrangements you need. It is likely that this group has to be earthed at a zener barrier earth. For further information, refer to the documentation for the external devices which are connected to the installation.



Appendix D Units and conversion factors

7955 (Appx-D /AD) Page D.1

Appendix D Units and conversion factors The figures in the following table are taken from BS 350: Part 1: March 1974.

Parameter Imperial units Metric equivalent

Length 1 inch

1 foot

25.4 mm

0.3048 m

Mass 1 lb

1 ton

0.45359237 kg

1016.05 kg

Density 1 lb/ft3

1 lb/gal

1 lb/US gal

16.0185 kg/m3

99.7763 kg/m3

119.826 kg/m3

Pressure

1 lb/in2

1 atm

1 MPa

1 N/m

1 mm Hg (0o)

1 in Hg (0o)

68.9476 mbar

1.013250 bar

10 bar

10-5 bar

1.33322 x 10-3 bar

33.8639 x 10-3 bar

Volume or capacity

1 in3

1 ft3

1 gal

1 US gal

1 US barrel

16.8371 cm3

0.0283168 m3

4.54609 dm3

3.78541 dm3

0.158987 m3

Volume flow 1 ft3/min

1 gal/min

40.776 m3/day

6.5463 m3/day

Mass flow 1 lb/hr

1 ton/hr

10.886 kg/day

1016.05 kg/hr

Energy 1 BTU

1 kWh

1 therm

1.05506 kJ

3.6 MJ

105.506 MJ

Temperature oF (1.8 x oC) + 32

Viscosity (dynamic) 1 P

1 lbf/(ft s) or 1 pdl s/ft2

1 slug/(ft s) or 1 lbf s/ft2

0.1 Pa s

1.48816 Pa s

47.8803 Pa s

Viscosity (kinematic) 1 St

1 ft2/s

1 cm2/s

9.29030 dm2/s

Appendix D Units and conversion factors

Page D.2 7955 (Appx-D /AD)

Appendix E Data tables

7955 (AppxE/AD) Page E.1


E.1 The tables Note: The equations used to derive these tables are given in Section E.2.

Density/temperature relationship of crude oil

Temp.(°C) Density (kg/m3)

60 738.91 765.06 791.94 817.15 843.11 869.01 894.86 920.87 946.46

55 742.96 768.98 794.93 820.83 846.68 872.48 898.24 923.95 949.63

50 747.00 772.89 798.72 824.51 850.25 875.94 901.80 927.23 952.82

45 751.03 776.79 802.50 828.17 853.81 879.40 904.96 930.50 956.00

40 755.05 780.68 806.27 831.83 857.36 882.85 908.32 933.76 959.18

35 759.06 784.57 810.04 835.48 860.90 886.30 911.67 937.02 962.36

30 763.06 788.44 813.79 839.12 864.44 889.73 915.01 940.28 965.53

25 767.05 792.30 817.54 842.76 867.97 893.16 918.35 943.52 968.89

20 771.03 796.18 821.27 846.38 871.49 896.59 921.68 946.77 971.85

15.556 774.56 799.57 824.59 849.60 874.61 899.62 924.63 949.64 974.65

15 775.00 800.00 825.00 850.00 875.00 900.00 925.00 950.00 975.00

10 778.95 803.83 828.72 853.61 878.50 903.41 928.32 953.23 978.15

5 782.90 807.65 832.42 857.20 882.00 906.81 931.62 958.45 981.29

0 786.83 811.46 836.12 860.79 885.49 910.21 934.92 959.66 984.42

Density/temperature relationship of refined products

Temp.(°C) Density (kg/m3)

60 605.51 657.32 708.88 766.17 817.90 868.47 918.99 969.45 1019.87

55 610.59 662.12 713.50 769.97 821.49 872.00 922.46 972.87 1023.24

50 615.51 666.91 718.11 773.75 825.08 875.53 925.92 976.28 1026.60

45 620.49 671.68 722.71 777.53 828.67 879.04 929.38 979.69 1029.96

40 625.45 676.44 727.29 781.30 832.24 882.56 932.84 983.09 1033.32

35 630.40 681.18 731.86 785.86 835.81 886.06 938.28 986.48 1038.67

30 635.33 685.92 736.42 788.81 839.37 889.56 939.72 989.87 1040.01

25 640.24 690.63 740.96 792.55 842.92 893.04 943.16 993.26 1043.35

20 645.13 695.32 745.49 796.28 846.46 896.53 946.58 996.63 1046.68

15.556 649.46 699.48 749.50 799.59 849.61 899.61 949.62 999.63 1049.63

15 650.00 700.00 750.00 800.00 850.00 900.00 950.00 1000.00 1050.00

10 654.85 704.66 754.50 803.71 853.53 903.47 953.41 1003.36 1053.32

5 659.67 709.30 758.97 807.41 857.04 906.92 956.81 1006.72 1056.63

0 664.47 713.92 763.44 811.10 860.55 910.37 960.20 1010.07 1059.93

The two tables above are derived from equations in the Revised Petroleum Measurement Tables (IP 200, ASTM D1250, API 2540 and ISO R91 Addendum 1).


Page E.2 7955 (AppxE/AD)

Platinum resistance law (To DIN 43 760)

°C Ohms °C Ohms °C Ohms °C Ohms °C Ohms

-220 10.41 -120 52.04 -20 92.13 80 130.89 180 168.47

-210 14.36 -110 56.13 -10 96.07 90 134.70 190 172.16

-200 18.53 -100 60.20 0 100.00 100 138.50 200 175.8

-190 22.78 -90 64.25 10 103.90 110 142.28 220 183.17

-180 27.05 -80 68.28 20 107.79 120 146.06 240 190.46

-170 31.28 -70 72.29 30 111.67 130 149.82 260 197.70

-160 35.48 -60 76.28 40 115.54 140 153.57 280 204.88

-150 39.65 -50 80.25 50 119.40 150 157.32

-140 43.80 -40 84.71 60 123.24 160 161.05

-130 47.93 -30 88.17 70 127.07 170 164.76

Density of ambient air (in kg/m3) at a relative humidity of 50%

Air Pressure

Air Temperature (°C)

(mb) 6 10 14 18 22 26 30

900 1.122 1.105 1.089 1.073 1.057 1.041 1.025

930 1.159 1.142 1.125 1.109 1.092 1.076 1.060

960 1.197 1.179 1.162 1.145 1.128 1.111 1.094

990 1.234 1.216 1.198 1.180 1.163 1.146 1.129

1020 1.271 1.253 1.234 1.216 1.199 1.181 1.163

Density of pure water (in kg/m3 to ITS - 90 Temperature Scale)

Temp °C

0

2

4

6

8

10

12

14

16

18

0 999.840 999.940 999.972 999.940 999.848 999.699 999.497 999.244 998.943 998.595

20 998.203 997.769 997.295 996.782 996.231 995.645 995.024 994.369 993.681 992.962

40 992.212 991.432 990.623 989.786 988.922 988.030 987.113 986.169 985.201 984.208

60 983.191 982.150 981.086 980.000 978.890 977.759 976.607 975.432 974.237 973.021

80 971.785 970.528 969.252 967.955 966.640 965.305 963.950 962.577 961.185 959.774

100 958.345



Velocity of Sound in Liquids The values for a selection of fluids are given below. You can obtain further details from reference books such as Tables of Physical and Chemical Constants and some Mathematical Functions by G W C Kaye and T H Laby.

Liquid Temperature (t °C)

Velocity of Sound ( c ) ms-1)

Rate of Change ( t/c δδ ms-1K-1)

Acetic acid 20 1173 ----

Acetone 20 1190 -4.5

Amyl acetate 29 1173 ----

Aniline 20 1656 -4.0

Benzine 20 1320 -5.0

Blood (horse) 37 1571 ----

Butyl acetate 30 1172 -3.2

Carbon disulphide 25 1142 ----

Carbon tetrachloride 20 940 -3.0

Chlorine 20 850 -3.8

Chlorobenzene 20 1290 -4.3

Chloroform 20 990 -3.3

Ethanol amide 25 1724 -3.4

Ethyl acetate 30 1133 -3.9

Ethyl alcohol 20 1162 -3.6

Formic acid 20 1360 -3.5

Heptane 20 1160 -4.5

n-Hexane 30 1060 ----

Kerosene 25 1315 -3.6

Menthol 50 1271 ----

Methyl acetate 30 1131 -3.7

Methyl alcohol 20 1121 -3.5

Methylene Chloride 25 1070 ----

Nitrogen -189 745 -10.6

Nonane 20 1248 ----

Oil (castor) 19 1500 -4.1

Oil (olive) 22 1440 -2.8

Octane 20 1197 ----

Oxygen -186 950 -6.9

n-Pentane 20 1044 -4.2

n-Propyl acetate 26 1182 ----

Toluene 20 1044 -4.2

Turpentine 25 1225 ----

Water (distilled) 10 1447.2 ----

20 1482.3 ----

30 1509.1 ----

50 1542.5 ----



Water (sea) -4 1430.2 ----

00 1449.5 ----

05 1471.1 ----

15 1507.1 ----

25 1534.7 ----

o-Xylene 22 1352 ----



E.2. Equations used to derive data tables Density/temperature relationship The density/temperature relationship is:

where: tρ = density at line temperature t°C (kg/m3)

15ρ = density at base temperature 15°C (kg/m3)

tΔ = t°C -15°C (i.e. t - base temperature)

15α = tangent thermal expansion coefficient per °C at base temperature 15°C

Tangent thermal expansion coefficient The tangent thermal expansion coefficient differs for each of the major groups of hydrocarbons. It is obtained from the equation:

Product compressibility The definition of compressibility used to develop the table in Section 1 of the IP Petroleum measurement Manual is the isothermal secant compressibility, defined by the equation:

T21

21

0 PP

VV

V

1⎥⎦

⎤⎢⎣

⎡−

∂−∂−=β

Where: β = isothermal secant compressibility at temperature T

0V = volume of liquid at atmospheric pressure

1V∂ = change in volume from 0V to 1V

2V∂ = change in volume from 0V to 2V

1V & 2V = volumes at pressures 1P and 2P , respectively

1P & 2P = gauge pressure readings (Bar)

( )[ ]t15t1515t 8.01exp Δα+Δα−ρ=ρ

215

151015

KK

ρ

ρ+=α

Where 0K and 1K are API factors which are obtained from the table:

Product Density Range

(kg/m3)

0K 1K

Crude Oil 771 - 981 613.97226 0.00000

Gasolines 654 - 779 346.42278 0.43884

Kerosines 779 - 839 594.54180 0.00000

Fuel Oils 839 - 1075 186.96960 0.48618



For practical purposes, when the liquid volume changes from 0V to 1V as the gauge pressure changes

from zero (atmospheric) to 1P , the above equation is simplified to:

T1

1

0 P

V

V

1⎥⎦

⎤⎢⎣

⎡∂−=β

ISO Document TC 28/SC3/N248, (Generation of New Compressibility Tables for International Use) gives the following equations relating β to the compressibility data:

ρ−ρ−+= eee logT0161654.0log02909.3T00343804.038315.1Clog

and

16 bar10C −××=β

Where: T = oil temperature in °C

r = oil density in kg/litre at 15°C

The new equation (from the API Manual of Petroleum Measurement Standards, Chapter 11.2.1M) gives (after converting to units of kg/m and bar):

1

10t2092.41087096.0t00021592.062080.1

4 bare10 152

3

152

6

−⎟⎟⎠

⎞⎜⎜⎝

⎛

ρ××+

ρ×+×+−

−=β

Where: T = temperature in °C

r15 = density (in kg/m3) at 15°C and at atmospheric pressure

This equation is valid for the density range of 638 kg/m3 to 1074 kg/m3. For a density range of 350 kg/m3 to 637 kg/m3 refer to Chapter 11.2.2M in the API Manual.

Velocity of sound in liquids The velocity of sound in dilational waves in unbound fluids is given by:

( ) 2

1

ac −ρβ=

Where: c = velocity of sound

aβ = adiabatic compressibility

ρ = density

Appendix F Calculations

7955 2540 (APPX-F /AB) Page F.1

Appendix F Calculations Indicated Volume Flow Rate Equation: IV = Freq / K Where: IV -Indicated Volume Freq -Frequency K -K-factor

Gross Volume Flow Rate Equation: GV = IV * MF Where: GV -Gross Volume IV -Indicated Volume MF -Meter Factor

Nett Volume Flow Rate Equation: NV = GV * (1 - BSW%/100) Where: NV -Nett Volume GV -Gross Volume BSW -Base Sediment & Water

Indicated Standard Volume Flow Rate Equation: ISV = IV * VCF Where: ISV -Indicated Standard Volume IV -Indicated Volume VCF -Volume Correction Factor

Gross Standard Volume Flow Rate Equation: GSV = IV * CCF Where: GSV -Gross Standard Volume IV -Indicated Volume CCF -Combined Correction

Mass Flow Rate Equation: M = GV * D Where: M -Mass Flow Rate GV -Gross Volume D -Flow Density

Appendix F Calculations

Page F.2 7955 2540 (APPX-F /AA)

Volume Correction Factor Equation: VCF = CTL * CPL or alternatively: VCF = Density / Base Density Where: VCF -Volume Correction Factor CTL -Temperature Correction CPL -Pressure Correction

Combined Correction Factor Equation: CCF = CTL * CPL * MF or alternatively: CCF = ( Density / Base Density ) * MF Where: CCF -Combined Correction CTL -Temperature Correction CPL -Pressure Correction MF -Meter Factor

Turbine Frequency Equation: Freq = Pulses / TimeInSec Where: Freq -Frequency Pulses -pulse count TimeInSec -Sample Time period

Specific Gravity Equation: SG = BaseDensity / WaterDensity Where: SG -Specific Gravity BaseDensity WaterDensity

Density & Base Density Density, Base Density, CTL, & CPL, are calculated according to: API-MPMS chapter 11.1 1980 using tables 53A & 53B, API-MPMS chapter 11.2.1M 1984 API-MPMS chapter 11.2.2M

7955 Flow Computer

Operating ManualHB552540May 2010

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Operating Manual HB552540 7955 Flow Computer May 2010 ... · You obey any other common-sense precautions which may apply to your situation. If you obey these sensible precautions,