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Mini CORI-FLOW Compact Coriolis Mass Flow
Meters/Controllers for Liquids and Gases
Doc nr.: 9.17.050J Date: 21-12-2015
ATTENTION Please read this instruction manual carefully before installing and operating the instrument. Not following the guidelines could result in personal injury and/or damage to the equipment.
Instruction manual
BRONKHORST®
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SCOPE OF THIS MANUAL This manual covers the general part of digital mini CORI-FLOW mass flow instruments for gases and liquids. It treats the general instructions needed for the instruments. More information can be found in other documents. Mini CORI-FLOW instruments have modular instruction manuals consisting of: - Short form instruction manual mini CORI-FLOW (document nr. 9.17.052)
- General instructions mini CORI-FLOW (document nr. 9.17.050)
- Operation instructions digital instruments (document nr. 9.17.023)
- Fieldbus/interface description:
- FLOW-BUS Interface (document nr. 9.17.024) - PROFIBUS-DP Interface (document nr. 9.17.025) - DeviceNet Interface (document nr. 9.17.026) - RS232 Interface with FLOW-BUS protocol (document nr. 9.17.027) - Modbus interface (document nr. 9.17.035)
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Even though care has been taken in the preparation and publication of the contents of this manual, we do not assume legal or other liability for any inaccuracy, mistake, mis-statement or any other error of whatsoever nature contained herein. The material in this manual is for information purposes only, and is subject to change without notice. Warranty The products of Bronkhorst® are warranted against defects in material and workmanship for a period of three years from the date of shipment, provided they are used in accordance with the ordering specifications and the instructions in this manual and that they are not subjected to abuse, physical damage or contamination. Products that do not operate properly during this period may be repaired or replaced at no charge. Repairs are normally warranted for one year or the balance of the original warranty, whichever is the longer. See also paragraph 9 of the Conditions of sales. The warranty includes all initial and latent defects, random failures, and undeterminable internal causes. It excludes failures and damage caused by the customer, such as contamination, improper electrical hook-up, physical shock etc. Re-conditioning of products primarily returned for warranty service that is partly or wholly judged non-warranty may be charged for. Bronkhorst High-Tech B.V. prepays outgoing freight charges when any party of the service is performed under warranty, unless otherwise agreed upon beforehand. However, if the product has been returned collect to Bronkhorst High-Tech B.V., these costs are added to the repair invoice. Import and/or export charges, foreign shipping methods/carriers are paid for by the customer.
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TABLE OF CONTENTS 1 INTRODUCTION .............................................................................................................................................. 6
1.1 General description ................................................................................................................................... 6 1.1.1 Gas / Liquid flow ................................................................................................................................. 6 1.1.2 Housing .............................................................................................................................................. 6 1.1.3 Valves ................................................................................................................................................ 7 1.1.4 Badger Meter Valves .......................................................................................................................... 9 1.1.5 Liquid dosing systems with pumps................................................................................................... 10
1.2 Sensor measuring principle ..................................................................................................................... 11 1.2.1 Mini CORI-FLOW sensor ................................................................................................................. 11
1.3 Valve principles ....................................................................................................................................... 11 1.3.1 Solenoid valve .................................................................................................................................. 11 1.3.2 Vary-P valve ..................................................................................................................................... 11 1.3.3 Pilot operated valve .......................................................................................................................... 11
1.4 Software for physical properties of gases and liquids. ............................................................................ 12 1.5 (mini) Cori-Flow accuracy ........................................................................................................................ 12
2 INSTALLATION .............................................................................................................................................. 16 2.1 Receipt of equipment .............................................................................................................................. 16 2.2 Return shipment ...................................................................................................................................... 16 2.3 Service .................................................................................................................................................... 16 2.4 Mounting instructions .............................................................................................................................. 17
2.4.1 Flow direction: .................................................................................................................................. 17 2.4.2 Base mounting: ................................................................................................................................ 17 2.4.3 Mounting position general: ............................................................................................................... 17 2.4.4 Mounting position (integrated) valve with purge connector: ............................................................. 17 2.4.5 Mounting position in pipe line for liquid applications: ....................................................................... 18 2.4.6 Liquid purging: .................................................................................................................................. 18 2.4.7 Mounting position in pipe line for gas applications: .......................................................................... 18 2.4.8 Gas purging: ..................................................................................................................................... 19 2.4.9 Inlet bends and pipe support: ........................................................................................................... 19 2.4.10 Pipe line reducers: ........................................................................................................................... 19 2.4.11 Vibrations: ........................................................................................................................................ 19 2.4.12 Crosstalk: ......................................................................................................................................... 20
2.5 Notes for temperature considerations ..................................................................................................... 20 2.6 Fluid/gas connections .............................................................................................................................. 21 2.7 Piping....................................................................................................................................................... 21 2.8 Electrical connections .............................................................................................................................. 22 2.9 Pressure testing ...................................................................................................................................... 23 2.10 Supply pressure ................................................................................................................................... 23 2.11 System purging .................................................................................................................................... 23 2.12 Seals .................................................................................................................................................... 23 2.13 Equipment storage............................................................................................................................... 23 2.14 Electromagnetic compatibility .............................................................................................................. 24 2.15 Electro static discharge........................................................................................................................ 25
3 OPERATION .................................................................................................................................................. 25 3.1 General .................................................................................................................................................... 25 3.2 Power and warm-up ................................................................................................................................ 25 3.3 Start-up .................................................................................................................................................... 25 3.4 Zeroing .................................................................................................................................................... 26
3.4.1 What is zero-stability ? ..................................................................................................................... 26 3.4.2 Procedure for zeroing ....................................................................................................................... 26 3.4.3 Zero-procedure information ............................................................................................................. 26 3.4.4 Alternatives for starting zero procedure ........................................................................................... 27 3.4.5 Zeroing with the Micro-switch ........................................................................................................... 27 3.4.6 Zeroing through the digital communication ...................................................................................... 27
3.5 Operating conditions ............................................................................................................................... 28 3.6 Manual operation ..................................................................................................................................... 28 3.7 Analog operation ..................................................................................................................................... 28 3.8 BUS / digital operation ............................................................................................................................. 29 3.9 RS232 communication cable T-part ........................................................................................................ 30
4 MAINTENANCE ............................................................................................................................................. 31 4.1 General .................................................................................................................................................... 31 4.2 mini CORI-FLOW sensor ........................................................................................................................ 31 4.3 Controllers ............................................................................................................................................... 31
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4.4 Control valves .......................................................................................................................................... 31 4.4.1 Solenoid valves ................................................................................................................................ 31 4.4.2 Vary-P valve ..................................................................................................................................... 31 4.4.3 Pilot operated valve .......................................................................................................................... 32
4.5 Kv-value calculation ................................................................................................................................. 32 4.5.1 For gases ......................................................................................................................................... 32 4.5.2 For Liquids ....................................................................................................................................... 33
4.6 Calibration procedure .............................................................................................................................. 34 4.7 Instrument re-ranging .............................................................................................................................. 35 4.8 Instrument filter settings .......................................................................................................................... 35
5 INTERFACE DESCRIPTION.......................................................................................................................... 36 6 TROUBLESHOOTING ................................................................................................................................... 36
6.1 General .................................................................................................................................................... 36 6.2 Calibration check ..................................................................................................................................... 36 6.3 Troubleshooting summary general .......................................................................................................... 37
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1 INTRODUCTION 1.1 General description 1.1.1 Gas / Liquid flow The Bronkhorst® series mini CORI-FLOW mass-flow meter/controller for gases and liquids is an accurate device for measuring gas and liquid flows up to 200 bara depending on body rating, virtually independent of pressure and temperature changes. The mini CORI-FLOW is a real mass-flow meter/controller and measures the flow in mass, it does not matter what the properties of the gases or liquids are. The system can be completed with a control valve or a pump and flexible readout unit to measure and control gas and liquid flows. Mini CORI-FLOW series are precise and compact Mass Flow Meters and Controllers, based on the Coriolis measuring principle. Designed to cover the needs of the low flow market, there are 4 models to overlap flow ranges from 5 g/h up to 300 kg/h (full scale values), each offering “multi-range” functionality: factory calibrated ranges can be rescaled by the user, maintaining the original accuracy specs. The instruments are equipped with a robust IP65 weatherproof housing. Instruments of the mini CORI-FLOW series contain a uniquely shaped, single loop sensor tube, forming part of an oscillating system. When a fluid flows through the tube, Coriolis forces cause a variable phase shift, which is detected by sensors and fed into the integrally mounted pc-board. The resulting output signal is strictly proportional to the real mass flow rate. Coriolis mass flow measurement is fast, accurate and inherently bi-directional. The mini CORI-FLOW features density and temperature of the fluid as secondary outputs. 1.1.2 Housing Each instrument housing style incorporates several provisions to comply with EMC requirements. Also the instrument housing is a robust IP65 weatherproof housing. Meter housing M12-M14 Meter housing M15 Controller housing
with metal seal valve
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1.1.3 Valves M12, M13 and M14 mini CORI-FLOW controllers are fitted with a fixed or modular valve. The M15 mini CORI-FLOW controller can only be equipped with a modular valve.
Integrated valves for liquids and gases
For liquids the valve has an extra purge adaptor on top for de-gassing. In case of a modular valve it is attached by means of a port connector. Possible combinations:
Valves: C2I valve Direct operating valve for liquids (“open” sleeve) metal sealed with purge connector. C2I valve = normally closed
C5I valve Direct operating valve for liquid/gas metal sealed. C5I valve = normally closed
Liquid Gas
M12 C2I F-033CI
C0I, C1I F-033CI
M13 C2I C5I F-033CI
C01, C1I C5I F-033CI
M14 C2I F-033CI
C0I, C1I F-033CI
M15 C2I C5I F-033CI F-004AI
C5I F-033CI F-004AI F-012AI, F-013AI
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C0I / C1I valve Direct operating valve for gases metal sealed C0I valve = normally closed C1I valve = normally open
F-033CI valve Vary-P operating valve for liquid/gas elastomeric sealed F-033CI valve = normally closed
F-004AI / BI valve Bellow valve for liquid/gas elastomeric sealed F-004AI/BI valve = normally closed
F-012AI/F-013AI valve Pilot operated valve for gases elastomeric sealed F-012AI/F-013AI valve = normally closed
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1.1.4 Badger Meter Valves
For those special applications where the Bronkhorst valves do not meet the specifications anymore we can use Badger Meter valves as a good alternative. Reasons for using an alternative valve could be requirements for: - Higher maximum pressure or delta-pressure - Higher Kv-values - Higher or lower temperatures - Faster response time - Metal sealed (e.g. for supercritical gases like CO2 or
ethylene) Badger Meter offers a wide range and variety of valves. These membrane valves are operated indirectly using an I/P-converter
with compressed air. The I/P-converter is connected to the controller output of the mini CORI-FLOW. To be able to meet the quality and security standards Bronkhorst is used to, we will accept only those Badger Meter valves which meet the “Bronkhorst Quality Norm”. This norm includes certain predefined specifications to enable our production department to adjust, optimize and test these valves if they were Bronkhorst valves. Main items on this “Bronkhorst Quality Norm” are: • Limit amount of models: RC200, ¼”, ½” and 1” types • Special O-ring chambers in valve bodies for Swagelok RS adaptor types (no NPT) • If no O-rings possible: adaptors welded to valve body • Spindle seals: Kalrez compound 3035 (in stead of Teflon) for reduced emission
For operation interface: • ABB TEIP11 I/P-converter: input signal 4-20 mA / output signal 0,2-1 bara
(or 0.4-2 bara) • If not possible: Samson 3730-0 positioner Please note that for proper functioning of the pump or valve the MFC needs to be adjusted electrically and also needs to be provided with the right parameter settings. This will be taken care of in our factory. For pump- or valve connections in the field after delivery, please contact your local sales representative.
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1.1.5 Liquid dosing systems with pumps
In Bronkhorst liquid mass dosing systems Liqui-Flow or CORI-FLOW instruments control liquid mass flow using a pump through a U/f converter. The pump is just used as an actuator to follow the controller to achieve the wanted mass flow (setpoint). It is not used as a positioner as it normally is, using the standard pump control software. Normally Bronkhorst will take care of all electrical and mechanical connections between the parts as mentioned above are realized, as well as an optimization of the PID-control and a test on water/IPA (when possible). The analog controller output signal, which normally would be used to drive a proportional valve, is limited to either 10 Vdc/15 Vdc and connected to the analog input signal of the pump drive. Each Liquid Dosing System consists of a flow sensor with controlling function, a pump and all inter-connecting material. A filter and check valve can be supplied on request. Furthermore, Bronkhorst will take care of electrical and mechanical connection, testing and optimization including the PID-integrated controller. In addition to the Bronkhorst Liquid Pump for small flow ranges, a complete series of pumps is available for those applications which require higher flow rates, higher pressures, wide control ranges or aggressive fluids. Further to operation in an analog mode, the system can also be used digitally with RS232 or with on-board interface to PROFIBUS-DP®, DeviceNet™, Modbus-RTU, or FLOW-BUS. See picture below for schematic setup.
Please note that for proper functioning of the pump or valve the MFC needs to be adjusted electrically and also needs to be provided with the right parameter settings. This will be taken care of in our factory. For pump- or valve connections in the field after delivery, please contact your local sales representative.
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1.2 Sensor measuring principle 1.2.1 Mini CORI-FLOW sensor Mini CORI-FLOW mass flow meters/controllers operate according to the Coriolis principle. The instrument can be used to simultaneously measure the mass flow, temperature and density. When a fluid flows through a vibrating tube, Coriolis forces are generated which bend or twist the tube. The extremely small tube displacements are detected by optimally positioned sensors and evaluated electronically. Since the measured phase shift of the sensor signals is proportional to the mass flow, the mini CORI-FLOW measures the mass flow directly. The measurement principle is independent of the density, temperature, viscosity, pressure, heat-capacity or conductivity. The tubes always vibrate at their natural frequency, which is a function not only of the tube geometry and the tube material properties but also the mass of the fluid in the vibrating tubes. 1.3 Valve principles Control valves are not designed to provide positive shut-off, although some models have excellent capabilities for this purpose. It is recommended to install a separate shut-off valve in the line if required. Also pressure surges, as may occur during system pressurisation must be avoided. The following models can be distinguished: 1.3.1 Solenoid valve
This is considered to be the standard (direct operated) control valve. In general it is a normally closed solenoid valve. The plunger is lifted by the force of the magnetic field of the coil. The orifice under the plunger is removable for optimising the orifice diameter. Also a normally opened solenoid valve is available.
1.3.2 Vary-P valve
For process conditions where up- and downstream pressure varies much, a special type of valve, VARY-P has been designed. This valve consists of two valves, a solenoid operated control valve and a fixed adjusted pressure compensation valve.
1.3.3 Pilot operated valve
For high flow rates the pilot operated valve has been designed. A solenoid driven control valve controls the pressure difference across a piston, which lifts the main plunger.
Flow controlvalve
pressurecompensatingvalve
flow controlvalve
P1
pilot valve pressure compensating valve
P2
flow control valve
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1.4 Software for physical properties of gases and liquids. Bronkhorst has access to the physical properties of over 600 fluids in a database called FLUIDAT. Application software, such as FLOW CALCULATIONS, enables the user to calculate properties, not only at 20°C / 1 atm but also at any temperature/pressure combination, both for gases and for liquids. Apply to your distributor for more details about this software. 1.5 (mini) Cori-Flow accuracy Zeroing of a (mini) Cori-Flow instrument is required each time process conditions have been changed. What is zero-stability ? Due to mechanical construction of the sensor tubes each (mini) Cori-Flow sensor will have a very small offset signal, even when the mass flow is zero. This is called the zero-stability error and is specified for accuracy separately for all Coriolis instruments. Main reason for this is the fact that this error can be (temporarily) neutralized after performing a zero-action. Immediately after zeroing, zero-stability error is 0%. However, it is allowed to move between a certain band depending on the environment (process) and fluid conditions. In ideal situations, where actual process conditions do not change, this error will remain the same. See below for possible reasons of change of zero-stability. See also paragraph 3.4.1. to learn how to zero. Zero-stability depends on the (mini) Cori-Flow model:
Model DN (mm) Zero-stability Nominal flow M12 0.25 < 0.1 g/h 100 g/h M13 0.5 < 0.2 g/h 1 kg/h M14 1.3 < 6 g/h 10 kg/h M15 3.12 < 50 g/h 100 kg/h M53 1 < 10 g/h 5 kg/h M54 2 < 50 g/h 50 kg/h M55 4 < 100 g/h 500 kg/h
Nominal flow: mass flow rate of liquid at a pressure drop of approx. 1 bar and based on reference conditions of water at approx. 20 °C NOTE: In practice zero-stability turns out to be better than the values in the table, but for calculation we will take worst case values. Accuracy The accuracy of a (mini) Cori-Flow is either 0.2% reading for liquids or 0.5% reading for gases. This specification is based on mass flow (e.g. g/h, kg/h, etc.). If the instrument will be used on volume flow (e.g. l/h, ml/min, etc) this will introduce an extra inaccuracy, based on the density (measurement). Process conditions Each time process conditions have been changed significantly a (mini) Cori-Flow needs to be zeroed in order to get rid of the offset error due to zero-stability. At least the very first time an instrument is used a zero procedure will be required. The zero-stability error will mainly change when one or more of the following items change significantly: • Temperature (of fluid or environment) • Pressure • Density of fluid • Vibrations working on instrument via environment • Pulsation of supply pressure working on instrument
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What changes are allowed ? How many changes in quantity for certain process conditions are allowed without the need of a new zero procedure for the (mini) Cori-Flow depends on the influence this will have on the mass in the tubes. As soon as a fluid will be measured at its critical point, a small change in process conditions like temperature or pressure can already result in a rapid increase or decrease of density and/or dynamic viscosity. This will also influence the mass (flow) in the sensor tubes and therefore the zero stability. So please try to avoid phase changes or almost phase changes. E.g. CO2 and Ethylene have a large transition area (“no meat, no fish”). Experiences in practice turned out that measuring (and even controlling) in such an area can be highly accurate. So measuring in critical, or even supercritical area’s, is good possible with (mini) Cori-Flow. Inaccuracies are to be expected when a phase change takes place. See also gas or liquid. Temperature changes of several °C or pressure changes of several bar for e.g. Air when measuring at 20°C and 5 bara will not be a problem. This will not affect density or dynamic viscosity that much. However when measuring e.g. Ethylene at 10°C and 52 bara, a small increase of temperature or decrease of pressure will already result in large changes of density and even phase change. This last example might need a new zero procedure to get rid of offset errors due to zero stability. Error visualization -> time Temperature considerations Effects on accuracy: (Mini) Cori-Flow sensors do have an internal temperature measurement device for measuring fluid temperature and compensation on mechanical changes of the sensor due to temperature changes.
0 %
+ x % error (zero stability)
- x % error (zero stability)
+/- 0.05% repeatability
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Error calculation: Total error = accuracy reading ± [(zero stab./flow)x100] [% reading] Example 1: error at 10 kg/h reading at M14 for a liquid (= ±0.2% of reading) zero stability error of M14 < 6 g/h; calculate with 6 g/h Total error = ±(0.2% + (6/10000 * 100))% = ±(0.2 + 0.06)% = ±0.26 % (= ± 26 g/h) Example 2: error at 500 g/h reading at M13 for gases (= ±0.5% of reading) zero stability error of M13 < 0.2 g/h; calculate with 0.2 g/h Total error = ± (0.5% + (0.2/500 * 100))% = ±(0.5 + 0.04)% = ±0.54 % (= ± 2.7 g/h) Example 3: Total error of M14 (at constant temperature)
Total error M14 up to 30 kg/h
-4%
-3%
-2%
-1%
0%
1%
2%
3%
4%
0 5000 10000 15000 20000 25000 30000
Flow [g/h]
Max
. err
or [%
RD
]
|0.2| %RD + |6| g/h
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Gas and liquid (mini) Cori-Flows can be used for gases and liquids. In all instruments capable of density measurement (e.g. mini CORI-FLOW series) there will be an automatic adjustment for change in density. CORI-FLOW M50-series however, cannot measure density. For those instruments it is advisable to calibrate them on air for gases and on water for liquids. Multi-range instrument Thanks to extremely high linearity of the sensor, (mini) Cori-Flow instruments can be easily re-ranged to a different full scale range (100% point). The analog output and the digital measured flow value will be scaled to this FS 100% point. E.g. An M13 can be used for a full scale between 50 g/h and 2000 g/h. Switching between these ranges can be realized using fieldbus, E-8000, Bright module or RS232 interface. There is free tooling software (FlowPlot) available for this purpose. Mini Cori-Flow instruments will get a calibration certificate for all possible FS ranges. The actual FS of the instrument is set to a value wanted by the customer and can be found on the gray sticker on the instrument. Summary In general: a (mini) Cori-Flow instrument is independent of physical properties. Performing an auto-zero on actual conditions (with zero flow) before use will get rid of offsets in the sensor. When these properties, like temperature, pressure, density and dynamic viscosity do not affect the mass in the tube or the mechanical sensor construction to much, error due to zero-stability will be small. Environment conditions are important to the mechanical behaviour of the sensor: • Vibrations (of sensor, rack, pipes etc.) with frequencies or harmonics close to the sensor’s natural
frequency could result in errors in the measurement. Sensor oscillation frequencies vary from 90…450 Hz, depending on the model.
• Pulsation of supply pressure may have negative influence on accuracy. Avoiding this is the best. Filtering is an option for improvement.
• Turbulences in flow may add extra noise to the measured value. Especially with high flow of gases straight pipes with lengths of 20..30 cm. at least are advisable for realizing a more undisturbed flow. For other applications (e.g. liquids) inlets of about 10x inner diameter of tube are sufficient. Smooth reducing from wide to small tubes is advisable. See below:
Optimal angle is approx. 7° • Gas bubbles entrapped in liquids (and/or locked-up in sensor tube) give disturbances to flow
measurement, especially in the lower flow ranges. Try to avoid this and purge with high flow to remove them.
• Fluid drops in gas flow (and/or locked-up in sensor tube) give disturbances to flow measurement, especially in lower flow ranges. Try to avoid this and purge with high flow to remove them.
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2 INSTALLATION 2.1 Receipt of equipment Check the outside packing box for damage incurred during shipment. Should the packing box be damaged, then the local carrier must be notified at once regarding his liability, if so required. At the same time a report should be submitted to:
BRONKHORST HIGH-TECH B.V. RUURLO HOLLAND
If applicable, otherwise contact your distributor. Remove the envelope containing the packing list; carefully remove the equipment from the packing box. Do not discard spare or replacement parts with the packing material and inspect the contents for damaged or missing parts.
2.2 Return shipment When returning material, always describe the problem and if possible the work to be done, in a covering letter. It is absolutely required to notify the factory if toxic or dangerous fluids have been metered with the instrument! This to enable the factory to take sufficient precautionary measures to safe-guard the staff in their repair department. Take proper care of packaging. If possible use the original packing box. Seal instrument in plastic Contaminated instruments must be dispatched with a completely filled in 'declaration on contamination form'. Contaminated instruments without this declaration will not be accepted. Note: If the instruments have been used with toxic or dangerous fluids the customer should pre-clean the instrument. Important: Clearly note, on top of the package, the customer clearance number of Bronkhorst High-Tech B.V., namely:
NL818936514B01
If applicable, otherwise contact your distributor for local arrangements. 2.3 Service If the equipment is not properly serviced, serious personal injury and/or damage to the equipment could be the result. It is therefore important that servicing is performed by trained and qualified service personnel. Bronkhorst High-Tech B.V. has a trained staff of servicemen available.
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2.4 Mounting instructions
2.4.1 Flow direction: Install the mini CORI-FLOW in accordance with the direction of the FLOW arrow. The arrow for flow direction is indicated on the mini CORI-FLOW, between process fittings.
2.4.2 Base mounting:
Mount the mini CORI-FLOW instrument, with screws in the body, to a rigid, stiff base body or heavy mass on a vibration-free position, such as a wall, heavy rig or stable construction. This is essential to achieve optimal accuracy with the mini CORI-FLOW instrument. Examples: M1 M2 M3
If there is no firm, steady, vibration-free base available, Bronkhorst® can offer a special mounting block for achieving optimal accuracy with the mini CORI-FLOW instrument. This mounting block has a mass and stiffness precisely tuned for the specific mini CORI-FLOW model and can be used as a base. Please contact your local sales representative.
2.4.3 Mounting position general: For gas and liquid mini CORI-FLOW meters can be mounted in any position for a proper measurement. M4 M5 M6
2.4.4 Mounting position (integrated) valve with purge connector: Only for mini CORI-FLOW instruments with (integrated) liquid valve with purge adaptor, mounting position can be critical for a good quality of de-gassing.
M7 M8 M9
Gas bubbles might collect in sensor ! + Prevent running dry !
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2.4.5 Mounting position in pipe line for liquid applications: For liquids, mount the mini CORI-FLOW at a level in the pipe where gas entrainment is not possible and be certain that the mini CORI-FLOW is filled at all times during operation. Try to avoid gas accumulation (in the sensor tube) at the highest point of a pipeline or in front of a control valve. Gas bubbles in the sensor tube may result in measuring errors. If there is gas entrainment, make sure gas bubbles can easily get out of the mini CORI-FLOW and piping. M10 M11 M12
Prevent running dry! M13 M14 M15
Gas bubbles might collect in sensor! Gas bubbles might collect in sensor! Gas bubbles might collect in sensor!
2.4.6 Liquid purging: In order to remove gas bubbles during start-up, flushing with relatively high flow rate of liquid for some minutes is recommended.
2.4.7 Mounting position in pipe line for gas applications: For gases mount the mini CORI-FLOW at a level in the pipe line system where condensate can not accumulate in the mini CORI-FLOW. Especially take care at the lower 3 situations at zero flow. M16 M17 M18
M19 M20 M21
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2.4.8 Gas purging: In order to remove condensation drops during start-up, flushing with dry gas for some minutes with high flow rate is recommended. Leak tightness: Verification of leaks is required prior starting up of the process.
2.4.9 Inlet bends and pipe support: Avoid pipe bends too close to the mini CORI-FLOW inlet. This might cause turbulence (especially for gases). Use pipe supports on equal distance of mini CORI-FLOW inlet and outlet. M22 M23 M24
2.4.10 Pipe line reducers: Avoid abrupt pipeline reducers and other obstructions in the piping. They can cause cavitation inside the meter tubes and will result in higher pressure drops. Mount reducers outside the rigid pipe supports. M25 M26
2.4.11 Vibrations: Avoid vibrations or mechanical shocks on the mini CORI-FLOW. Flow vibrations of pumps can influence meter performances. Therefore avoid connecting the pump directly to the meter or install a dampening device. A flexible connection (eg. Teflon tubing) or extra loop in the piping to neutralize vibrations is advised. Do not mount the sensor in areas subject to vibration. M27 M28 M29
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2.4.12 Crosstalk: Be carefull when mounting two or more mini CORI-FLOW instruments close together. Vibrations from one instrument might interfere with the resonance frequency of another instrument. Therefore, for multiple mini CORI-FLOW instruments: mount them on rigid, stiff bases/masses individually, but mechanically isolated from each other. Special mounting blocks can be isolated using rubber suspension or caps for muffling/damping. These mounting blocks can be optionally obtained at your local sales representative. It is favourable to mount the instruments parallel to each other. Examples: M30 M31
2.5 Notes for temperature considerations The mini CORI-FLOW has to be installed in such a way that levels of different temperature within the mini CORI-FLOW are avoided. Avoid multiple heating and cooling of the instrument. Temperature shocks have to be avoided in any case. (max. 1°C/sec) After using the mini CORI-FLOW the first time at low temperature tighten the connector screws again in order to prevent any leakage! Please note: if you do not tighten the screws, the leaking connector / fitting can cause damage! After the first shrinking and tightening of the screws, no further precaution is necessary. Note that the maximum temperature in the housing of the mini CORI-FLOW is allowed to be up to 70 ºC max. Also note that a mini CORI-FLOW will have an amount of self-heating due to the power dissipation on the electronics (DSP). This self-heating can be up to approx. 15 ºC. It will be at maximum if there is no flow (less cooling). In practice, there will be a balance between fluid temperature, self heating, cooling effects and ambient temperature at the instrument. If the fluid is really hot, it would help if the instrument is in a cool environment. It will also depend on how well the installation where the instrument has been mounted in/on is capable of cooling. Anyway, one must take care that the instrument in the housing will not exceed the 70 °C, otherwise the electronics will be damaged. To check this, the internal temperature sensor can be used. Via FLOW-DDE/E-8000 or Bright it can be read out. (FlowDDE par. 142). Please make sure the temperature value readout here (=actual temperature in housing) will not exceed 70 °C. On the next page some facts about maximum Tambient and Tfluid:
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Max. temperature in housing is 70ºC,but: Operating temperature conditions (continuous):
Tfluid + Tambient < 110ºC With: Tfluid < 100ºC Tambient < 55ºC
For cleaning purpose, instrument without power (continuous)
Tfluid + Tambient < 130ºC With: Tfluid < 130ºC T ambient < 80ºC
In all situations:
Tfluid > 0 ºC Tambient > 0 ºC Storage temperature (dry tube) [-30 .. 80] ºC
2.6 Fluid/gas connections Bronkhorst® mini CORI-FLOW meters/controllers are equipped with compression or face-seal-fittings. For leak tight installation of compression type fittings make sure that the tube is inserted to the shoulder in the fitting body and that no dirt or dust is present on tube, ferrules or fittings. Tighten the nut finger-tight; while holding the instrument and then tighten the nut 1 turn. If applicable follow the guidelines of the supplier of the fittings. Special types of fittings are available on request. * Note: Always check your system for leaks, before applying fluid/gas pressure. Especially if toxic, explosive or
other dangerous fluids are used. 2.7 Piping BE SURE THAT PIPING IS ABSOLUTELY CLEAN! DO NOT install small diameter piping on high flow rates, because the inlet jet-flow will affect the accuracy. DO NOT mount abrupt angles direct on in- and outlet, especially not with high flow rates. We recommend at least 20 pipe diameters distance between the angle and the instrument. Special care should be taken in regard to reducers placed just in front of the mini CORI-FLOW. High pressure drop and flow disturbance can occur which can influence the mini CORI-FLOW. Warning! During the manufacturing process, the instruments have been tested with water. Despite the fact that the instruments have been purged thoroughly afterwards, we cannot guarantee that the delivered instruments are absolutely free from water droplets. Bronkhorst® strongly recommends performing an additional, adequate drying procedure for those applications where remaining water particles may cause undesired reactions such as corrosion.
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2.8 Electrical connections Bronkhorst® recommends using their standard cables. These cables have the right connectors and if loose ends are used, these will be marked to prevent wrong connection.
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2.9 Pressure testing Each CORI-FLOW is pressure tested to at least 1.5 times the working pressure of the process conditions stipulated by the customer, with a minimum of 8 bara. The tested pressure is stated on the flow meter/controller with a RED COLOURED sticker. Check test pressure before installing in the line. If the sticker is not available or the test pressure is incorrect, the instrument should not be mounted in the process line and be returned to the factory. Each instrument is helium leak tested to at least 2⋅10-9 mbar l/s Helium outboard. 2.10 Supply pressure Do not apply pressure until electrical connections are made. When applying pressure to the system, take care to avoid pressure shocks in the system and increase pressure gradually, especially on high pressure units incorporating a piston operated control valve. Make sure in case of a controller that the used valve can withstand the system pressure. Give special attention to the maximum delta pressure of the valve. 2.11 System purging If explosive gases are to be used, purge the process with inert dry gas like Nitrogen, Argon etc. for at least 30 minutes at a high enough flow. In systems with corrosive or reactive fluids, purging with an inert gas is absolutely necessary, before taking in use. Preventing chemical reactions inside the tubes or instrument as this will tend to clog up or corrode the system. Complete purging is also required to remove such fluids from the system before exposing the system to air. It is preferred not to expose the system to air, when working with these corrosive fluids. 2.12 Seals Bronkhorst® has gathered a material compatibility chart from a number of sources believed to be reliable. However, it is a general guide only. Operating conditions may substantially change the accuracy of this guide. Therefore there is no liability for damages occurring from the use of this guide. The customer’s application will demand its own specific design or test evaluation for optimum reliability. So check if the seals like O-rings and plunger are correct for the process. 2.13 Equipment storage The equipment should be stored in its original packing in a cupboard warehouse or similar. Care should be taken not to subject the equipment to excessive temperatures, humidity, vibrations or shocks.
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2.14 Electromagnetic compatibility Conditions for compliance with EMC requirements All instruments described in this manual carry the CE-mark. Therefore they have to comply with the EMC requirements, as they are valid for these instruments. However compliance with the EMC requirements is not possible without the use of proper cables and connector/gland assemblies. For good results Bronkhorst ® can provide standard cables. Otherwise follow the guidelines as stated below. 1. Connector mini CORI-FLOW
Note: When connecting the system to other devices (e.g. to PLC), be sure that the integrity of the shielding is not affected. Do not use unshielded wire terminals. 1. For FLOW-BUS S(F)TP data (patch) cable connection to M12 connectors follow the instructions of the
supplier. It is important to use shielded twisted pair cables and shielded RJ45 modular jack connectors. 2. For PROFIBUS-DP, Modbus or DeviceNet data cable connections follow the instructions of the cable
suppliers for the specific field-bus system.
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2.15 Electro static discharge This instrument contains electronic components that are susceptible to damage by static electric discharges. Proper handling procedures must be taken during installation, removing and connecting the electronics.
3 OPERATION 3.1 General The Bronkhorst® instruments are designed in such a way that they will meet user process requirements in the best possible way. The mini CORI-FLOW meters/controllers can be powered from +15 Vdc to +24 Vdc. When providing your own power supply be sure that voltage and current rating are according to the specifications of the instrument(s) and furthermore that the source is capable of delivering enough power to the instrument(s). Cable wire diameters should be sufficient to carry the supply current and voltage losses must be kept as low as possible. When in doubt: consult factory. Mini CORI-FLOW instruments can be operated by means of:
1. Analog interface (0...5Vdc/0...10Vdc/0...20mA/4...20mA) 2. RS232 interface (connected to COM-port by means of special cable on 38400 Baud) 3. FLOW-BUS 4. PROFIBUS-DP 5. DeviceNet 6. Modbus 7. other fieldbus interfaces on request
Option 1 and 2 are always present on multibus instruments. An interface to any available fieldbus is optional. Operation via analog interface, RS232 interface and an optional fieldbus can be performed at the same time. A special parameter called “control mode” indicates to which setpoint the controller should respond: analog or digital (via fieldbus or RS232). The RS232 interface behaves like a FLOW-BUS interface. When using more interfaces at the same time, reading and operation can be done simultaneously without problems. When changing a parameter value, the last value send by an interface will be valid. Also the push-button switch and the LED’s on the left side of the instrument can be used for manual operation of some options. The green LED will indicate in what mode the instrument is active. The red LED will indicate error/warning situations. 3.2 Power and warm-up Before switching on power, check if all connections have been made according to the hook-up diagram which belongs to the instrument. Check fluid connections and make sure there is no leakage. If needed, purge the system with a proper fluid. For a gas instrument only purging with gases is allowed. Liquid instruments may be purged with either a gas or a liquid, whatever is needed for the purpose. Turn on power and allow at least 30 minutes to warm up and stabilise. In cases where no electronics are involved (valves only) warming up is not needed. During warm-up period, fluid pressure may either be on or off. 3.3 Start-up Turn on fluid supply gently. Avoid pressure shocks, and bring the instrument gradually up to the level of the actual operating conditions. Also switch off fluid supply gently when shutting down.
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3.4 Zeroing 3.4.1 What is zero-stability ? Due to mechanical construction of the sensor tubes each Coriolis sensor will have a very small offset signal, even when the mass flow is zero. This is called the zero-stability error and is specified for accuracy separately for all Coriolis instruments. Main reason for this is the fact that this error can be neutralized after performing a zero-action. Immediately after zeroing, zero-stability error is 0%. However it is allowed to move between a certain band depending on the environment and fluid conditions. In ideal situations where actual process conditions do not change, this error will remain the same. Each time process conditions have been changed significantly a mini CORI-FLOW needs to be zeroed in order to get rid of the offset error due to zero-stability. At least the very first time an instrument is used a zero procedure will be required. The zero-stability error might change when one or more of the following items change significantly: Mainly: • Temperature (of fluid and environment) • Mounting position of instrument Less important: • Dynamic viscosity of fluid • Vibrations working on instrument via environment • Pulsation of supply pressure working on instrument • Pressure • Density of fluid 3.4.2 Procedure for zeroing (See also Short form instruction manual mini CORI-FLOW, document nr. 9.17.052) • Warm-up instrument for at least 30 minutes. • Purge as long as needed with fluid to make sure there is no gas in the liquid or no condensate in the gas • Fill instrument with fluid under process conditions. • Close all valves at output to establish zero flow. Closing valves at input will not be critical (under
circumstances even better to let them open) but extra shut-off valves at output should be closed, as well as control valve of instrument e.g. by means of setpoint = 0% or control mode = “close valve” .
• To start the zero procedure: Press push-button switch (#) on the side of the instrument and hold it (LED’s will respond) until only the green LED is burning and then release the button. This command is also possible via any available fieldbus- or RS232 interface.
• The zeroing procedure will start at that moment and can be monitored by the LED’s. The green LED will blink until the procedure is ready. This will take about 30 seconds.
• When it is ready it will burn green continuously again. 3.4.3 Zero-procedure information If the instrument has problems finding a proper and stable zero, it will repeat the auto-zero step a few times (max. 4 times). Each time no proper zero can be achieved, the instrument will give a short notice signalling its LED’s after the procedure. The red and green LED will blink turn-by-turn for a few seconds to indicate that the auto-zero wasn’t able to find a zero (because of too much noise in the signal). This is mostly the case when the instrument is placed in a vibrating environment. When ready zeroing after trying several (max. 4) times, the final result for the zero value will be a moving average value of all attempts. The instrument will save this zero value into its non-volatile memory and will keep this value until a next zero-procedure will be performed. This value (Sensor Input Zero Scale Adjustment) can be accessed (read/written), via parameter 218 in the parameter table of FlowDDE (note: Depending on firmware of instrument). The mini CORI-FLOW will accept a proper zero only if the measured signal is within a limited noise band. Best way to achieve this is to avoid external noise influences. However, when this is not possible, filter settings of the mini CORI-FLOW can be changed to improve noise immunity. Important: Always make sure that there is absolutely no flow when the instrument is performing the (auto-)zero procedure and there are no vibrations or pulsating inlet pressures.
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3.4.4 Alternatives for starting zero procedure • Through FLOW-BUS, using an E-8000 readout/control module. • Through FLOW-BUS, via a RS232/FLOW-BUS converter using software on a PC or PLC. • Through RS232, using software on a PC or PLC • Through RS232, using a Bright compact local readout/control module • Through other fieldbus system (PROFIBUS-DP/DeviceNet/ModBus) 3.4.5 Zeroing with the Micro-switch Before using the instrument zeroing is required. • Set process conditions
After warm-up, pressure up and fill system including the mini CORI-FLOW according to the process conditions.
• Stop flow Make sure there is no flow through the instrument by closing the shut-off valves before and after the instrument.
• Press and hold, until GREEN LED is on, than release button With no flow, use the push-button switch (#) on the left side of the instrument to start the zero adjustment procedure. Press the push-button (#) and hold it, after a short time the red LED will go ON and OFF then the green LED will go ON. At that moment release the push-button (#).
• Zeroing The zeroing procedure will start at that moment and the green LED will blink fast. The zeroing procedure waits for a stable signal and saves the zero. If the signal is not stable, zeroing will take long and the nearest point to zero is accepted. The procedure will take approx. 25 sec. Make sure that there is no flow through the instrument when performing the zeroing procedure.
• Ready When indication is showing 0% signal and the green indication LED is continuously on, then zero has been performed well.
3.4.6 Zeroing through the digital communication It is also possible to start the zero adjustment procedure through the FLOW-BUS, using an E-8000 readout/control unit or a software program on a PC, connected to a FLOW-BUS interface module. The following parameters must be used for zeroing an instrument:
Initreset [unsigned char, RW,0...255, DDEpar. = 7, Proces/par. = 0/10] Cntrlmode [unsigned char, RW,0...255, DDEpar. = 12, Proces/par. = 1/4]
CalMode [unsigned char, RW,0...255, DDEpar. = 58, Proces/par. = 115/1] • Set process conditions
Warm-up, pressure up the system and fill the instrument according to the process conditions. • Stop flow
Make sure there is no flow through the instrument by closing the shut-off valves before and after the instrument.
• Send parameters Send the following values to the parameters in this sequence. Initreset 64
Cntrlmode 9 Calmode 255 Calmode 0 Calmode 9 • Zeroing
The zeroing procedure will start at that moment and the green LED will blink fast. The zeroing procedure waits for a stable signal and saves the zero. If the signal is not stable zeroing, will take long and the nearest point to zero is accepted. The procedure will take approx. 25 sec. Make sure there is no flow through the instrument when performing the zeroing procedure.
• Ready When indication is showing 0% signal and the green indication LED is burning continuously again, then zeroing has been performed well. Also parameter control mode goes back to its original value. As last send 0 to parameter initreset.
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0V common-
Current output signals
Sourcing
instrument
output I+
mA
3.5 Operating conditions Each instrument has been adjusted for customer process conditions, if possible. Controllers or valves may not operate correctly, if process conditions vary too much, because of the restriction of the orifice in the valve. Please change supply- or backpressure to improve control behaviour. If this does not help, contact your local sales representative to assist you. 3.6 Manual operation By means of manual operation of the push-button switch (#) some important actions for the instrument can be selected/started. These options are available in both analog and BUS/digital operation modes. (See also manual operation in document number 9.17.023) These functions are:
- Reset (instrument firmware-program reset) - Reset in case of an alarm - Zeroing - Restore factory settings (in case of unintentionally change of the settings) for FLOW-BUS only: - Automatic installation to FLOW-BUS (installs instrument to free address) - Remote installation to FLOW-BUS (instruments will be installed by PC-software)
3.7 Analog operation Digital instruments can be operated with analog signals through the 8-pin circular connector. The instruments are compatible in use with analog instruments on this point. Analog operated instruments, can be hooked up using an 8-wire shielded cable, connected according to the Bronkhorst® standard. Each electronic PC-board is set for one of the following output (and corresponding input) signals: Signal output (sensor) input (setpoint) code signal signal A 0…5 Vdc 0…5 Vdc B 0…10 Vdc 0…10 Vdc F 0…20 mA (sourcing) 0…20 mA (sinking) G 4…20 mA (sourcing) 4…20 mA (sinking) For meters only the output signal is available. At analog operation the following parameters are available:
- measured value - setpoint (controllers only) - valve voltage (controllers only)
Note: When operating the instrument through the analog interface it is possible to connect the instrument to any supported fieldbus system (or RS232-interface with special cable) for reading/changing parameters (e.g. controller response or other fluid selection). For FLOW-BUS versions of the instruments a readout/control module for digital instruments can be temporarily connected to the M12 fieldbus connector.
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3.8 BUS / digital operation Operation via fieldbus reduces the amount of cables to build a system of several instruments and offers more parameter values to be monitored/changed by the user. See instruction manual: operating digital mass flow / pressure instruments for more details (document nr. 9.17.023). Operation by means of a fieldbus adds a lot of extra features (compared to analog operation) to the instruments. Such as:
- adjustable filter settings to smoothen or speed-up the output signal - setpoint slope (ramp function on setpoint for smooth control) - adjustment of controller output (response time) for valve or pump control (PID-settings) - direct reading at readout/control module or host computer - testing and self diagnosis - response alarm (setpoint-measure too high for too long time) - several control/setpoint modes (e.g. purge/close valve) - master/slave modes for ratio control (FLOW-BUS only) - identification (serial number, model number, device type, user tag) - adjustable minimal and maximal alarm limits - (batch) counter - adjustable response time for controller when opening from zero - adjustable response time for normal control - adjustable response time for stable control (|setpoint-measure| < 2%)
Special software like FlowDDE, FlowPlot and FlowView can be used to control these settings. For operation of digital instruments by means of a specific fieldbus system or RS232, see following documents (available as PDF-file):
• for FLOW-BUS document number: 9.17.024 • for PROFIBUS-DP document number: 9.17.025 • for DeviceNet document number: 9.17.026 • for RS232 document number 9.17.027 • for Modbus document number 9.17.035
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3.9 RS232 communication cable T-part
Note: Special RS232 cable has partnr. 7.03.444 and consists of a T-part with 1 male and 1 female 8-pin DIN connector on one instrument-side and a normal female sub-D 9 connector on the side of the computer. By means of this cable it is possible to offer RS232 communication and still be able to connect power-supply and analog interface through the (analog) 8-pin DIN connector. RS232 communication is only possible with a baudrate of 38.4 KBaud and can be used for either: • Uploading new firmware by means of a special program (for trained Bronkhorst-service personnel only) • Servicing your instrument using Bronkhorst-service programs (for trained Bronkhorst-service personnel
only) • Operating your instrument using FLOWDDE, FLOWB32.DLL or RS232-ASCII protocol (end user)
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4 MAINTENANCE 4.1 General No routine maintenance is required to be performed on the meters or controllers. In case of severe contamination it may be required to clean the valve orifice separately. 4.2 mini CORI-FLOW sensor The mini CORI-FLOW sensor is constructed in such a way that there is very little dead volume. The sensor is maintenance free. 4.3 Controllers All sensor types can be combined with a control valve to be operated together as a control loop. Controller systems are either available as separate units; a sensor and a control valve, or as an integrated unit. If applicable maintenance procedures are described under “control valves” 4.4 Control valves Control valves cannot be used for shut-off and/or on-off applications. Pressure surges, as may occur during system pressurisation or deflation must be avoided. 4.4.1 Solenoid valves These are considered to be the directly operated control and pilot valves. They can be disassembled in the field by the user for cleaning and servicing. The parts can be cleaned with a cleaning liquid, or in an ultrasonic bath. To disassemble the valve proceed as follows: a) disconnect the instrument connector (not necessary with separate valve) b) remove the hex nut on top of the valve assembly c) lift the cover (coil) assembly d) unscrew the flange e) lift valve assembly carefully from the base f) unscrew set screw for the orifice and subsequently loosen the orifice and the orifice holder g) remove the plunger assembly Clean parts and carefully re-assemble in reverse order. It is recommended to replace the O-rings prior to re-assembly. After having re-assembled the control valve, it is recommended to check the control characteristics of the valve. This can best be done by using a separate variable 15 Vdc power supply source. Proceed as follows: - disconnect the valve leads and connect to supply source - apply gas pressure as per working conditions - apply power by gradually increasing voltage - the valve should open at 7 Vdc ± 3 Vdc - the fully opened position is reached at approx. 9 Vdc ± 1.5 Vdc. In case the valve does not operate within the voltage levels stated, then it must be disassembled, and the orifice must be adjusted to the proper position. Re-assemble valve and repeat procedure if required. 4.4.2 Vary-P valve The vary-P valve is designed to cope with extremely varying process conditions on either upstream or downstream side of the valve or a combination of these. ∆p can vary over a wide range. The basic control valve is a direct operated solenoid control valve. The design has been patented. For orifice selection and maintenance other than the pilot valve consult the factory.
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4.4.3 Pilot operated valve This control valve is an indirect control valve, consisting of a spring loaded membrane/orifice system which is positioned by a solenoid operated direct control (pilot valve). The two devices are integrated in one block. Basically follow the same procedures for dis-assembly as stipulated under “Solenoid valves” For cleaning purposes it may be required to dis-assemble further, i.e. also remove the membrane assembly. For pilot operated valves the maximum pressure drop is limited to 20 bard. If the pressure drop during start-up is higher, it is preferred to install a bypass valve. During start-up this valve should be opened. Also the minimum pressure drop is limited. For exact figures consult factory or proceed according to the technical data and/or additional instructions given by the sales office or department. Note: When pressure testing a system incorporating a pilot operated control valve, a special procedure must be followed in order to prevent damage to the valve. In such cases it is necessary to contact the factory prior to do this.
4.5 Kv-value calculation This calculation method can be used to determine the Kv-value of the main orifice of a control valve. 4.5.1 For gases Determine desired ∆p across valve. ∆p must be at least 20% of supply pressure, or in closed loop systems, of total pressure difference in the loop. If ∆p is 20-50% of supply pressure, use formula:
2514 pp
TK n
n
mv ⋅∆
⋅⋅
Φ=
ρρ
under critical
If ∆P is 50-100% of supply pressure, use formula:
Tp
K nn
mv ⋅
⋅⋅Φ
= ρρ 1257
over critical
Units: Φm = flow [kg/h] p1 = supply pressure [bara] p2 = downstream pressure [bara] ∆p = pressure difference (p1 - p2) [bara] T = temperature [K] ρn = density [kg/mn
3]
The orifice diameter can be determined by: d= 7.6 K v [mm]
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4.5.2 For Liquids Determine desired ∆p across valve. ∆p must be at least 50% of supply pressure
Kv-value calculation 1000p
K mv ⋅∆
Φ=
ρρ
Units: flow - )/h(kgmΦ
density - ρ(kg / m ) at 20 C3 and 1 atm.
delta p - ∆p(bard) The orifice bore diameter can be determined by:
d 7.6 K v= [mm] For C2 type of valves the diameter of the orifice can be calculated as shown above or looked up in the graph below.
Φ Φv 2 v2
H O = customercustomer
H Oρρ
in which: Φv = volume flow ρ = density
104
103
101
10-1 101100
104
103
102
101
P (bar)
d = 0.1 mm
d = 0.37 mm
d = 0.3 mm
d = 0.2 mm
d = 0.14 mm
102
100
10-2
O H O (ml/h)2
10-1 101100
d = 1.0 mm d = 0.7 mm
d = 0.5 mm
P max.
v
If liquids have viscosity’s >15 mPa.s (water = 1 mPa.s), the flat orifice and plunger type control mechanism cannot be used. For measuring systems only check maximum possible viscosity with factory.
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4.6 Calibration procedure All instruments are factory calibrated on all possible ranges, independent of customer conditions. Calibration will be performed with water under normal temperature and atmospheric conditions (20°C and 1 bara). After calibration the instruments will be dried thoroughly. Instruments will be calibrated using water on 6 points over the full flow range where the instrument can be used for. Because Coriolis instruments measure mass flow, they will have the same accuracy for all fluids and therefore calibrations on actual fluids will not be necessary. Also density will be calibrated and calibration checks on air will be performed. For the flow calibration, the instrument will be set to the maximum full scale value and seven points (including zero) will be compared with a reference. All points will be shown in a graph to illustrate that they are within limits of total accuracy (±0.2% ±Zero Stability). After this calibration, the actual capacity (full scale) value will be set to the wanted flow value ordered by the enduser. This value can be easily changed on site by the enduser using Bronkhorst tooling software (FlowDDE and FlowPlot) which can be downloaded from the website: http://downloads.bronkhorst.com/. Thus re-ranging the instrument will be possible between a minimum and a maximum capacity. Over this complete range the instrument calibration certificate will be valid. Analog outputs (A: 0…5Vdc /B: 0…10Vdc /F: 0…20mA /G: 4…20mA) for flow and analog inputs for giving setpoints to controllers, will be adjusted as ordered. These adjustments include an extra uncertainty of < ±0.1% at each input as well as at each output. The analog output and -input maximum values are equal to the actual capacity (full scale) value of the instrument and will be linear to the flow. If the instrument will be re-ranged: actual capacity will be set to another value, this analog value will get another meaning. The original, factory set, actual capacity (full scale) value and type of analog signal will be displayed on the grey sticker on the instrument. This will be the value what the instrument had been ordered for.
Example: M13 instrument has a maximum flow of max. 2000 g/h. It will be calibrated up to 2000 g/h on 7 points, including zero. Enduser wants to use it with 4…20 mA and orders the instrument for 150 g/h. When the instrument leaves the factory 20mA will correspond with 150 g/h. After re-ranging it to a full scale of 500 g/h, 20mA will correspond with 500 g/h Mix. After re-ranging it to a full scale of 2000 g/h, 20mA wil correspond with 2000 g/h. Note: The fluidname “Mix” is just indicative for actual use. However, the meter will measure all fluids with same accuracy as long as the instrument is capable of handling the fluid (pressure drop, corrosion resistance, suitability of valve or pump etc.).
G: 4…20mA analog input and output Capacity (FS) = 150 g/h Mix
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4.7 Instrument re-ranging Re-ranging can easily be performed by changing the capacity of the instrument. This can be performed by using FlowPlot, E-8000 or Bright readout/control module, RS232 digital communication or any available fieldbus communication interface supporting parameter 21: capacity. Capacity can be set between minimum capacity and maximum capacity. The actual values depend on the type of instrument. FlowPlot can be downloaded at: http://downloads.bronkhorst.com Example of changing flow range using FlowPlot:
Enter max flow range here (capacity) or move the slider.
4.8 Instrument filter settings
Changing filter settings can be done using FlowPlot. FlowPlot can be downloaded at: http://downloads.bronkhorst.com Output filter: Dynamic display factor and Static display factor are filter settings for readout only (at analog output and digital output). Output signal filtering at stable situation and at a flow-step can be set separately. Sensor filter: Exponential smoothing factor is the most important filter parameter to influence the stability of the meter and will also influence the controller behaviour, where it will be provided as input for the controller. Adaptive smoothing factor does not have functionality for a mini CORI-FLOW. For a mini CORI-FLOW it will temporarily switch off the filter during a flow-step to enable fast controller behaviour together with strong filtering. For all filter settings: A value can be entered between 0 and 1, where values close to 0 will filter strongly and slow down the output. A value close to 1 will speed-up the output and will introduce more noise. At value = 0, the filter has been switched off. No signal is put-through: no signal changing. At value = 1, the output is equal to the input: no filtering at all.
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5 INTERFACE DESCRIPTION For a description of the available interfaces see document numbers: 9.17.024 for FLOW-BUS 9.17.025 for PROFIBUS-DP 9.17.026 for DeviceNet 9.17.027 for RS232 9.17.035 for Modbus These documents are available as PDF on the documentation/software tool CD.
6 TROUBLESHOOTING 6.1 General For a correct analysis of the proper operation of a mini CORI-FLOW meter or controller it is recommended to remove the unit from the process line and check it without applying fluid supply pressure. In case the unit is dirty, this can be ascertained immediately by loosening the compression type couplings and, if applicable the flange on the inlet side. Energising or de-energising of the instrument indicates whether there is an electronic failure. When powering up the red LED is on and the green LED is flashing for a second or two. Then the instrument should go in normal operation mode. See document number 9.17.023 for detailed description of the LED indication. After that, fluid pressure is to be applied in order to check behaviour. 6.2 Calibration check In case of checking the instrument for correct calibration, the only proper way to do this is to use a weighing scale with correct accuracy. Alternatively another Coriolis instrument might be used as a reference. However, volumetric flow meters should not be used as a reference. The integrated totalizer of the instrument can be used to compare a batch of flow during several minutes to a weighing scale. The easiest way is to fill a cup, e.g. with water for 2 minutes or more. To activate and zero the totalizer, FlowPlot and FlowDDE can be used, to be downloaded at http://downloads.bronkhorst.com/. Alternatively a Bright module or E-8000 could be used to operate the counter for a mini CORI-FLOW. For this check, proceed as follows: - put an empty cup on the weighing scale - zero the scale with the empty cup on the scale - reset the totalizer of the mini CORI-FLOW before filling the cup - make sure the inlet pressure is stable and sufficient for proper control and correct flow rate - in case of a controller: give a setpoint to open the valve - in case of a meter, open a manual valve with correct inlet pressure - fill the cup during at least 2 minutes and stop the flow
(Totalizer can be used as batch controller to dose a certain batch within a certain time in case of controller) - compare the totalizer value to the value indicated by a weighing scale. - make sure you understand the total acceptable error = reading accuracy (0.2% for a liquid) ± zero stability
as explained in paragraph 1.5 NOTE: This method should be used only to get a quick impression about the calibration of the instrument. Please understand that performing an accurate calibration requires knowledge and optimal control of many parameters involved, such as: pressure, temperature, time-measurement, evaporation of liquid, mounting position of weighing scale, tubing and flow.
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6.3 Troubleshooting summary general Symptom Possible cause Action Red LED is irregular or continuously on.
Gas bubbles in tube (of liquid meter)
Purge to get rid of gas bubbles Advise: use frequency and/or density signal to detect if gas or liquid is in the tube.
Too much vibrations Mount isolation rubbers and flexible tubing. Red LED is continuously on Hardware error Have instrument checked by specialist Wanted flow is not reached Clogging of the instrument Purge at outlet and/or inlet with dry air if
possible and compare max flow with fixed inlet pressure to values in the table of the brochure or using CoriCalc pressure calculations.
No output signal No power supply 1a) check power supply 1b) check cable connection
Output stage damaged due to long lasting shortage and/or high-voltage peaks
1c) return to factory
Supply pressure too low, or differential pressure across meter too low
1d) increase supply pressure
Valve blocked/contaminated 1e) connect 0 .. 15 Vdc to valve and slowly increase voltage while supply pressure is ‘on’. The valve should open at 7V ± 3V; if not open, then clean parts and adjust valve (qualified personnel only)
Piping or filters blocked 1f) clean system Sensor failure 1g) return to factory
Maximum output signal Output stage damaged 2a) return to factory Sensor failure 2b) return to factory
Output signal much lower than setpoint signal or desired flow
Piping or filters blocked/contaminated 3a) clean system sensor blocked/contaminated 3b) clean sensor with a gas or fluid Valve blocked/contaminated 3c) clean valve Valve internal damage (swollen seat in plunger) 3d) replace plunger assembly and adjust valve
or return Incorrect type of gas is used and/or pressure/diff. pressure is to low
3e) try instrument on conditions for which it was designed
Flow is gradually decreasing Condensation, occurs withNH3 , hydrocarbons such as C H ,C H3 8 4 10 etc.
4a) decrease supply pressure and/or heat gas to be measured
Valve adjustment has changed 4b) see ‘1e’ Oscillation Supply pressure/diff. pressure too high 5a) lower pressure
Pipeline too short between pressure regulator and mini CORI-FLOW
5b) increase length or diameter of piping upstream Increase between pressure regulator and mini CORI-FLOW
External vibration is present 5c) Remove external vibration Valve sleeve or internals damaged 5d) replace damaged parts and adjust valve,
see ‘1e’ or return to factory Controller adjustment wrong 5e) adjust controller
Software like FLOWPLOT can be used to do this. Please contact the distributor for details. Unstable upstream pressure
Small flow at zero setpoint Valve leaks due to damaged plunger or dirt in orifice
6a) clean orifice and/or, when replacing plunger assembly, see ‘1e’
Pressure too high or much too low 6b) apply correct pressure Zero procedure not done or with gas in the tube 6c) Purge and Zero the instrument
High flow at zero setpoint Damaged diaphragm (only applicable to valves with membrane)
7a) replace membrane seal
Zero procedure not done or with gas in the tube 7b) Purge and Zero the instrument Disturbances in the flow Gas in the system 8a) Purge the system
Expansion of liquids to gasses
8b) Check properties fluid used Advise: use frequency and/or density signal to detect if gas or liquid is in the tube
Calibration error Zero procedure not done or with gas in the tube 9a) Purge and Zero the instrument Gas in the system 9b) Purge the system Measure time to short 9c) Measure long enough to get a reliable
measurement Right reference instrument 9d) The mini CORI-FLOW is a mass-flow
meter/controller and should not be checked with a volume-meter.
Totalization error Pulsating or fast changing flow Used special CORI-FILL (> 8V16) firmware specially optimized for totalizing flow. (Use dampener to stabilize inlet pressure.)
Note: For other (more specific) problems see also troubleshooting parts in other documents.
