TRANSMITTER TRANSMITTER Oleh: Roni Heru TriyantoOleh: Roni Heru Triyanto

Input Proses

valve status (open/close)switch position (on/off)

pump (start/stop)

Low Tank Level AlarmHigh Tank Level Alarm

Fire Alarm

pressuresflow rates

temperaturestank levels

PR

OC

ESS

Variables

Alarms

Device Status

FIE

LD

- INT

ER

FA

CE

Aspek Penting Peralatan Lapangan Range pengukuran

Kondisi Operasi Accuracy Precision Linearity Hysteresis Karakteristik Phisik

Efek temperatur Efek overpressure Efek vibration Efek humidity Efek power supply Efek Pembebanan dll

Metode Kalibrasi Dimensions/ Ukuran Umur Availability Product support

(maintenance) Spare parts

Range and Accuracy Range and Accuracy

• RangeRange– Nilai Minimum dan maximum dari besaran phisik yang Nilai Minimum dan maximum dari besaran phisik yang

dapat diukur pada kondisi operasidapat diukur pada kondisi operasi

• Accuracy Accuracy – Nilai yang didefinisikan yang merupakan batas sehingga Nilai yang didefinisikan yang merupakan batas sehingga

error tidak boleh lebih ketika peralatan digunakan pada error tidak boleh lebih ketika peralatan digunakan pada kondisi operasi. kondisi operasi.

– contoh :contoh :

• ± 1 ± 1 ooFF

• ± 1% of actual output reading± 1% of actual output reading

Linearity

Hysteresis

HysteresisPerbedaan maximum untuk input yang sama antara nilai keluaran upscale and downscale selama full range

hysteresis deadband

Repeatability & Reproducibility

RepeatabilityThe closeness of agreement among a number of consecutive measurements of the output for the same value of the input under the same operating conditions approaching from the same direction

ReproducibilityThe closeness of agreement among repeated measurements of the output for : the same value of input mode under the same operating conditions

over a period of time approaching from both directions

TransmitterTransmitter Kombinasi dari Kombinasi dari sensor and signal sensor and signal

conditioningconditioning digunakan untuk digunakan untuk mengukur besaran proses dengan jarak mengukur besaran proses dengan jarak jauh (remote). jauh (remote).

Transmitter Transmitter Process VariableProcess Variable (PV) bisa (PV) bisa didapatkan untuk disambungkan dengan didapatkan untuk disambungkan dengan peralatan akhir (display, recording or peralatan akhir (display, recording or analysis lanjutan).analysis lanjutan).

Transmitter

• Konfigurasi umum dari measurement transducer terdiri dari sensing element yang digabungkan dengan driving element (transmitter).

• Transducers mengkonversikan besaran dari sebuah process variable (seperti: flow rate, pressure, temperature, level, or concentration) kedalam sinyal yang dapat dikirim langsung ke controller/recorder/ indicator.

• The sensing element dibutuhkan untuk mengkonversikan besaran pengukuran, yaitu process variable, kedalam besaran lain sehingga dapat dihubungkan untuk mechanical or electrical processing didalam the transducer.

Standard Instrumentation Signal-Levels• Sebelum 1960-1970, instrumentasi di proses

Industri menggunakan sinyal pneumatic (udara bertekanan) untuk transmit/ mengirimkan informasi pengukuran dan pengendalian.

• Peralatan ini menggunakan mechanical force-balance elements to generate signals in the range of 3 to 15 psig (0.2 to 1.0 kg/cm2).

• Sekitar 1960-1970, Instrumentasi electronik telah banyak digunakan. Sinyal Output: Tegangan 1 – 5 V dc, Arus 4 – 20 mA dc

Input Output

50 °C 4 mA

150 °C 20 mA

• Instrument ini (transducer) mempunyai lower limit or zero: 50 °C dan span: 100 °C.

• Temperature transmitter diatas mempunyai hubungan output & input:

20 mA 4 mAmA 50 C 4 mA

150 C 50 C

mA0.16 C 4 mA

C

mT T

T

Konversi Sinyal

Pneumatic transmitterPneumatic transmitter Mengkonversikan pengukuran Mengkonversikan pengukuran physical physical

variablevariable ke sebuah ke sebuah standard pressure standard pressure signalsignal seperti dalam range 0.2 kg/cm seperti dalam range 0.2 kg/cm2 2 to to 1.0 kg/cm1.0 kg/cm2 2 (3-15 psig). (3-15 psig).

Signal tekanan dikirimkan melalui pipa / Signal tekanan dikirimkan melalui pipa / tubes ke gauge,chart recorder dan tubes ke gauge,chart recorder dan digunakan juga sebagai sinyal feedback digunakan juga sebagai sinyal feedback didalam aplikasi controldidalam aplikasi control

Pneumatic transmission: Pneumatic transmission: Problems?Problems?

Kebocoran internal and external,Kebocoran internal and external, pressure drops, pressure drops, Dibutuhkan udara yang bersih, Dibutuhkan udara yang bersih,

kering, tekanan yang tetap/ konstan,kering, tekanan yang tetap/ konstan, Sulit dikirim untuk jarak yang jauh,Sulit dikirim untuk jarak yang jauh, noise, mechanical vibrations,noise, mechanical vibrations, dll.dll.

Dalam aplikasi control:Dalam aplikasi control: Dibutuhkan sejumlah moving parts and Dibutuhkan sejumlah moving parts and

komponen,komponen, hysteresis, non-linearity,hysteresis, non-linearity, low response times,low response times, Sulit mendapatkan repeatability didalam Sulit mendapatkan repeatability didalam

control,control,

Pneumatic transmission: Pneumatic transmission: Problems?Problems?

Pneumatic TransmitterPneumatic Transmitter

Pneumatic Transmitter

Electronic TransmittersElectronic Transmitters

• Accuracy lebih baik,Accuracy lebih baik,

• linearity and repeatability, linearity and repeatability,

• measurement & control lebih measurement & control lebih sederhana sederhana

• Menurunkan biaya operasi & Menurunkan biaya operasi & maintenancemaintenance

• Memperbaiki transmittability untuk Memperbaiki transmittability untuk jarak yang lebih jauh.jarak yang lebih jauh.

ELECTRONIC TRANSMITTERSELECTRONIC TRANSMITTERS

Analog transmitter (4-20 mA dc atau 1 Analog transmitter (4-20 mA dc atau 1 – 5 V dc)– 5 V dc)

Analog - Digital/hybrid (SMART) Analog - Digital/hybrid (SMART) transmitterstransmitters Smart Smart

Digital Transmitter Digital Transmitter Fieldbus Fieldbus

Analog TransmittersAnalog Transmitters

• Analog transmittersAnalog transmitters mengkonversikan process variable kedalam sinyal process variable kedalam sinyal electrical (voltage or current)electrical (voltage or current) yang yang ekuivalen yang informasinya akan ekuivalen yang informasinya akan dibawa dengan kabel dari tempat dibawa dengan kabel dari tempat pengukuran ke control room yaitu untuk pengukuran ke control room yaitu untuk display atau process controller. display atau process controller.

voltage transmittersvoltage transmitters wire-resistance/impedance merupakan masalah wire-resistance/impedance merupakan masalah

yang penting, terutama untuk jarak yang jauh yang penting, terutama untuk jarak yang jauh signal attenuated sepanjang jalur kabelsignal attenuated sepanjang jalur kabel Sangat cocok untuk jarak yang pendekSangat cocok untuk jarak yang pendek Typical signal ranges (PV: 0% to 100%)Typical signal ranges (PV: 0% to 100%)

0 to 10V0 to 10V 0 to 5V0 to 5V 1 to 5 V1 to 5 V -10V to +10V-10V to +10V -5V to +5V, etc. -5V to +5V, etc.

Analog TransmittersAnalog Transmitters

current transmitterscurrent transmitters transmitter sebagai sumber arus/ current source transmitter sebagai sumber arus/ current source

(current generator). (current generator). wire-resistance tidak mempunyai efek pada aliran wire-resistance tidak mempunyai efek pada aliran

arus didalam current loop; arus didalam current loop; signal ranges 0-20mA, 4-20mA, 0-50 mA and 10-50 signal ranges 0-20mA, 4-20mA, 0-50 mA and 10-50

mAmA Arus sinyal 4-20mA digunakan untuk industry Arus sinyal 4-20mA digunakan untuk industry

standard. Arus 4 to 20mA merepresentasikan standard. Arus 4 to 20mA merepresentasikan seluruh span dengan minimum (0%) untuk 4mA and seluruh span dengan minimum (0%) untuk 4mA and maximum (100%) untuk 20mA.maximum (100%) untuk 20mA.

Analog TransmittersAnalog Transmitters

Analog Conventional Transmitter

• Transmitter selalu digunakan untuk mengkonversikan output sensor ke sinyal yang tepat untuk input controller, such as 4 to 20 mA.

• Transmitters biasanya dirancang untuk direct acting.

• Biasanya mempunyai zero dan span adjustment.

Four Wire Transmitter

Two Wire Transmitter

Smart TransmittersSmart Transmitters

Apa “smart” didalam Apa “smart” didalam transmitterstransmitters

FeaturesFeatures Benefits / AdvantagesBenefits / Advantages SMART ProtocolsSMART Protocols

Smart TransmittersSmart Transmitters

SMART TRANSMITTERSMART TRANSMITTER

SMART SMART atau atau INTELLIGENTINTELLIGENT

Telah menggunakan Telah menggunakan microprocessormicroprocessor. .

MicroprocessorMicroprocessor ditambahkan didalam ditambahkan didalam field-device sehingga terdapat field-device sehingga terdapat features features baru atau extra baru atau extra didalam peralatandidalam peralatan

Contoh: Transmitter & HART communicatorContoh: Transmitter & HART communicator

Smart Transmitter

Smart Transmitter

Smart Transmitter

Smart Transmitter

Smart TransmitterSmart Transmitter

CommunicationCommunication

Komunikasi digital menggunakan Komunikasi digital menggunakan dua kabel yang sama dengan yang dua kabel yang sama dengan yang digunakan untuk transmisi sinyal digunakan untuk transmisi sinyal analog analog

Komunikasi digital digunakan untuk Komunikasi digital digunakan untuk konfigurasi/ setting transmitterkonfigurasi/ setting transmitter

Untuk menyimpanUntuk menyimpan : tag – Identifikasi dari transmitter date modified – Waktu terakhir kalibrasi atau

instalasi message – nama peralatan, dll information untuk: flange type, flange material

O-ring, seal type, sensor range dll

Memory (EPROM) permits StorageMemory (EPROM) permits Storage

What is a fieldbus ?

Fieldbus

Digital, 2 way communication

I/O - system

4 – 20 mA

FieldbusFieldbus

Fieldbus pada Process Industry Fieldbus mempunyai banyak keuntungan

dibandingkan dengan Instrumentasi tradisional : Mengurangi jumlah pengkabelan Mendapatkan informasi lebih banyak dari peralatan seperti:

diagnostic information, device parameters dll. Commissioning dari devices terpusat. Asset management capabilities. Lebih fleksibel untuk system layout & design. Mudah dalam expansion & modification.

What are the fieldbus benefits?

reduced cabling

less hardware

simpler configuration

simpler maintenance

reliability

flexibility

more information from process to business level

Field Bus

PC Compatibility with Existing Systems

PC-based MMI

PC-based Par. DAQ

PC-basedPLC monitoring

TraditionalAnalog & Discrete

Instruments

Hybrid Instruments

Intelligent Instruments

I/O

4-20 mA

Controller

PLC

Host

PC-basedlab process

Analyzer

DCS CS 3000, YokogawaDCS CS 3000, Yokogawa

Master devices

Slave devices

TokenPLCPC

PROFIBUS

PROFIBUS Protocol

PLCclass 1 master

Engineering tool class 2 master

PLCclass 1 master

Data Exchangetoken token

token

Cyclic exchange

Acyclic exchange

Fieldbus signal

Manchester code signal

Instalasi Fieldbus

LAS: Link Active Scheduler

A link master (LM) is any device containing a link active scheduler. There must be at least one LM on a segment. When the LAS on a segment has failed, another LM on the same segment starts working as the LAS.

Transfer of LAS

Fieldbus : more than just communication

Unique Information is Maintained by Device

Fieldbus Installation

Fieldbus Wiring Example

Fieldbus Wiring

Fieldbus Wiring

Fieldbus Foundation

Number of devices per segment

• Based on present device power consumption, Power conditioner current limitation and resistance of wires, experience demonstrates that up to 16 Devices per segment can be used.

Same location after fixing the installation

Typical Installation

Sensor Characterisation DataSensor Characterisation Data

• Sensor linearization Coefficients or interpolation points for different T, P

• stored in the memory (EPROM) stored in the memory (EPROM)

• Sensor behaviour at various operating Sensor behaviour at various operating conditions is tested, and used for conditions is tested, and used for compensationcompensation

• Drastically reduces driftsDrastically reduces drifts

Processor: Enables Computations Processor: Enables Computations and Output Signal Optionsand Output Signal Options

• linear (for pressure, differential pressure, level measurement. ..),

• square root (for flow measurement with differential pressure meters),

• square root of third and fifth powers (for flow measurement in open channels..) etc,

• use values stored in table in the memory to calculate the value of process variable

Re-ranging, Turn-downRe-ranging, Turn-down• Adjust or Change the zero / span

• Send Command from Handheld/remote computer to the Process Transmitter

• Re-ranging can be performed without applying reference (pressure / temperature); uses Characterization data.

• Reranging done with reference will actually be more accurate calibration.

Limits / Alarm values Limits / Alarm values • High limit,

• low limit,

• high rate of change,

• low rate of change , etc.

depending on Make/Model

• Set output signal to 3.5mA or 21mA

Multidrop communication Multidrop communication Network More than one smart

transmitter using same two-wire loop.

Each transmitter configured a unique Address (Non-zero) “1 to 15”.

Each can be individually read, configured, reranged or calibrated. Each transmitter draws, outputs 4mA Only

In conventional analog mode, address set to “0”

Self-diagnosticsSelf-diagnostics • diagnostic to determine conditions of

sensor, communication line, power supply, configurations, etc.

• helps reduce trouble shooting efforts, improves servicing.

• Newer transmitters can sense impulse line plugging conditions.

• Rosemount : HART (Highway Addressable Remote Transducer)

• Honeywell : DE (Digitally Enhanced)

Common Smart Transmitter Communication ProtocolsCommunication Protocols

BENEFITS OF USING BENEFITS OF USING SMART TRANSMITTERSSMART TRANSMITTERS

• Improved SafetyImproved SafetyReranging, calibration, etc., can be done remotely without going to the actual transmitter site which may be in an hazardous or unsafe location.

• Time SavingsTime Savings• Remote communication implies

facility to rerange, reconfigure, etc. for one or more smart transmitters using the hand-held communicator or configurator;

means fewer trips to the field.

• Self - diagnostics,

implies lesser time spent for troubleshooting, repairs etc.

• High AccuracyHigh Accuracy• The process of analog-to-digital and

digital-to-analog conversion of the 4-20 signal are eliminated by the use of digital communication.

• Functions like sensor output compensation for drifts due to changing operating conditions,

• output linearisation

• or other computations, etc.

enable high accuracy of transmitted data.

• Reduced InventoryReduced Inventoryfacility to rerange the transmitter without loss of accuracy,

facility to configurate the transmitter when using a different process media,

computational abilities like square-root extraction, etc.,

imply that only one type of smart transmitter need to be purchased or maintained as spare for a wide range.

• Typical Smart Transmitter Models:Typical Smart Transmitter Models:• Foxboro 820 Series, 860 Series,• Honeywell ST-3000/100, ST-3000/600,

ST-3000/900,• Moore Products XTC,• Rosemount 3051C, 1151 Smart Enhanced, 1151

Smart Retrofit,• SMAR LD301,• ABB Kent-Taylor KS Series, 600T Series,• Bailey BCN,• Yokogawa UniDelta Mark II/COM,• FUJI FCX Series,• ………….., etc.,…….. And a lot many from others..

Advanced CapabilitiesAdvanced Capabilities

• Embedded control (PID)

• Multi-variate transmitters

• FIELDBUS (Fully Digital, Multidrop Networking)

Embedded control Embedded control Built in PID FunctionsBuilt in PID Functions

Multi-variate Multi-variate

Smart TransmittersSmart Transmitters

HART ProtocolHART Protocol

HART Communication between HART Communication between master and slavemaster and slave

• The master sends messages with requests for actual/specified values, and/or any other data/parameters available from the slave device.

• The slave interprets these instructions as defined in the HART protocol.

• The slave responds with status information and data for the master.

HART Commands HART Commands

• Universal commands

• Common practice commands

• Device-specific commands

• HART follows the Open Systems Interconnections (OSI) model of the International Organization for Standardization (ISO).

• The HART protocol uses a reduced OSI model, implementing only layers 1, 2 and 7

• Layer 1, physical layer

• Layer 2, link layer

• Layer 7, application layer

Question TopicsOSI layer

How do we make the connection?

Plugs, sockets, cablePhysical

What signals can I send?

Voltage, current, frequencyPhysical

How do I address a message?

None (point-to-point), numerical address, tag

DataLink

When can I send a message?

Access rules: master-slave, token-passing, collision-detection

DataLink

What messages can I send?

Coding: bits, characters, parityDataLink

Data types: bits, integers, floating point, text

Application

What does a message mean?

Standard functionsApplication

Function blocks, Device Descriptions"User"*

Specifying a Specifying a Smart Smart

TransmitterTransmitter