Commissioning Benefits

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Buddy Freeman
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1 Freedom to Choose. Power to Integrate. Commissioning Benefits Andreas Agostin MTL Instruments On behalf of Fieldbus Foundation Marketing Committee Freedom to Choose. Power to Integrate.

2 Commissioning Benefits? Since late 1990s, major end users like Shell, BP and Petronas are standardizing their installations on Foundation Fieldbus. First reports in 1997 by Dow Chemical 1 indicated 74% reduction in field wiring, a 93% reduction in required control room space, and an 80% reduction in field-device commissioning time over previous installations done with conventional input/output. Startup took only 15 man-hours instead of Too good to be true? Why do end users report significant reductions in time? Let us find out. Sources: 1 Gregory K. McMillan, Douglas M. Considine, Process/industrial instruments and controls handbook, McGraw Hill, InTech, June 1997, Dow claims first fieldbus installation, International Society of Automation (ISA), Freedom to Choose. Power to Integrate.

3 Contents About project commissioning Comparing 4-20mA and Fieldbus infrastructure Commissioning process 4-20mA Fieldbus Comparison Commissioning in practice Conclusion 3 Freedom to Choose. Power to Integrate.

4 About Project Commissioning Project commissioning is the process of assuring that all systems and components of a building or industrial plant are designed, installed, tested, operated, and maintained according to the operational requirements of the owner or final client. A commissioning process may be applied not only to new projects but also to existing units and systems subject to expansion, renovation or revamping. Source: Wikipedia 4 Freedom to Choose. Power to Integrate.

5 About Project Commissioning Apply engineering techniques and procedures to check, inspect and test every operational component of the project individual functions, such as instruments and equipment complex amalgamations such as modules, subsystems and systems 5 Freedom to Choose. Power to Integrate.

Comparing 4-20mA and Fieldbus Infrastructure One signal per I/O point Process value is coded in 4-20mA analog signal Only little diagnostics (LB/SC) Parallel connection

6 Comparing 4-20mA and Fieldbus Infrastructure One signal per I/O point Process value is coded in 4-20mA analog signal Only little diagnostics (LB/SC) Parallel connection Cable carries power and digital data Plenty of information Data integrity checks 4-20mA fieldbus I/O FF H1 FF PS T T Diagrams simplified 6 Freedom to Choose. Power to Integrate. 6

7 Commissioning Process 4-20mA 4-20mA 7 Freedom to Choose. Power to Integrate.

8 Commissioning Process 4-20mA 4-20mA Test Report 8 Freedom to Choose. Power to Integrate.

9 Commissioning Process 4-20mA 4-20mA Install the devices 9 Freedom to Choose. Power to Integrate.

10 Commissioning Process 4-20mA 4-20mA Install the devices Verify device installation 10 Freedom to Choose. Power to Integrate.

Commissioning Process 4-20mA 4-20mA Install the devices Verify device installation Install the DCS Assigning the I/O These two steps may also happen earlier or later in the commissioning process.

11 Commissioning Process 4-20mA 4-20mA Install the devices Verify device installation Install the DCS Assigning the I/O These two steps may also happen earlier or later in the commissioning process. The actual work on the I/O is system-dependent. The required steps would be: Determine which I/O point of the system is connected to which field instrument Assign/verify the tag (typically using walkie-talkie) Put it into the control application 11 Freedom to Choose. Power to Integrate.

12 Commissioning Process 4-20mA 4-20mA Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Thermocouple mv RTD Ohm 12 Freedom to Choose. Power to Integrate. Analog measurement can drift and must be calibrated from time to time

13 Commissioning Process 4-20mA 4-20mA Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Ranging Using HART (or sometimes DIP switches): 4mA shall be 20 C, 20mA shall be 120 C 13 Freedom to Choose. Power to Integrate.

Commissioning Process 4-20mA 4-20mA Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Ranging Calibrate the 4-20mA (current

14 Commissioning Process 4-20mA 4-20mA Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Ranging Calibrate the 4-20mA (current drift) Measure the output current with a precision tool 14 Freedom to Choose. Power to Integrate. Analog output can drift and must be calibrated from time to time Simulate a measurement value using HART

15 Commissioning Process 4-20mA 4-20mA Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Ranging Calibrate the 4-20mA (current drift) System ranging (DCS) DCS must know what 4mA means and what 20mA means. If your instrument is set to: 4mA shall be 20 C, 20mA shall be 120 C, your DCS must be set to the same range. 15 Freedom to Choose. Power to Integrate.

16 Ranging, 4-20mA Process 120 C Transmitter Range C 12 ma System Range C Reading 100 C...alarms and trips not working Instrument range and DCS system range must match Range #1 Range #2 CTRL Transmitter CPU D/A 4-20 ma AI A/D CPU AO D/A 4-20 ma Positioner A/D CPU 16 Freedom to Choose. Power to Integrate.

17 Commissioning Process 4-20mA 4-20mA Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Ranging Calibrate the 4-20mA (current drift) System ranging (DCS) System calibration 4-20mA (current drift) AI: Simulate a current and check the reading on the DCS AO: Set an output value on the console and verify the current 17 Freedom to Choose. Power to Integrate.

Commissioning Process Fieldbus Fieldbus Fieldbus

terminations, and hence reduces installation

18 Commissioning Process Fieldbus Fieldbus Fieldbus uses a bus structure, so a single trunk cable is run into the field. This reduces the number of required terminations, and hence reduces installation time and the number of potential points of failures. 18 Freedom to Choose. Power to Integrate.

19 Commissioning Process Fieldbus Fieldbus Cable parameter check-out (e.g. capacitance, inductance) may be omitted. Experience showed that parameters of cables registered with the Fieldbus Foundation are within the specification and do not require verification of the physical parameters. If your installation is known to be (fairly) reliable, you may also forgo the cable checkout completely. Faults can then be rectified using fieldbus diagnostics. 19 Freedom to Choose. Power to Integrate.

Commissioning Process Fieldbus Fieldbus Install

uses digital communication and requires dedicated

These Multimeters for fieldbus are operated

disadvantage arises out of being digital (which

20 Commissioning Process Fieldbus Fieldbus Install the devices Verify device installation Fieldbus uses digital communication and requires dedicated tools to verify proper installation. These Multimeters for fieldbus are operated similar to regular multimeters, so that no disadvantage arises out of being digital (which someone may perceive as complex). 20 Freedom to Choose. Power to Integrate.

21 Commissioning Process Fieldbus Fieldbus Install the devices Verify device installation To check that fieldbus devices are installed (wired) correctly, you can check one-by-one (easy to identify faults) or after all devices are installed (potentially faster if few mistakes are made). A good physical installation will ensure proper communication and - according to previous experience will avoid 80-95% of problems that occur in inferior installations. 21 Freedom to Choose. Power to Integrate.

systems offer commissioning wizards, that enable foolproof and fast

22 Commissioning Process Fieldbus Fieldbus Install the devices Verify device installation Install the DCS Assigning the I/O Fieldbus systems offer commissioning wizards, that enable foolproof and fast commissioning of FF instruments. 22 Freedom to Choose. Power to Integrate.

23 Commissioning Process Fieldbus Foundation Fieldbus devices are recognized by three mechanisms: node address for communication device tag corresponding to the project P&I diagram a unique identifier allowing the system to automatically resolve any tag or address conflicts Fieldbus Install the devices Verify device installation Install the DCS Assigning the I/O The system automatically assigns the address to all devices, avoiding human errors such as address duplication associated with manually managed protocols, and saving time. Therefore technicians work based on tag and need not be concerned with address. Thanks to the unique identifier, multiple devices can be connected and commissioned at the same time. It is plug-'n'-play. 23 Freedom to Choose. Power to Integrate.

24 Commissioning Process Fieldbus Fieldbus Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) For instruments with analog sensors such as RTDs or thermocouples, the measurement circuit may drift and may require calibration. For other types like time-of-flight (e.g. radar level sensor), they are considered digital and do not require calibration. 24 Freedom to Choose. Power to Integrate.

25 Commissioning Process Fieldbus Fieldbus Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Ranging Transmission is digital. A conversion from one unit to another takes place in the instrument function block: Example: A temperature may transmit its reading in C, F, or Kelvin. It may also scale a certain measurement range into a % value. There is no conversion required by the DCS, as the readings are all transmitted with the engineering unit included. 25 Freedom to Choose. Power to Integrate.

26 Ranging, 4-20mA Process 120 C Transmitter Range C 12 ma System Range C Reading 100 C...alarms and trips not working Results: Range mismatch Range exceeded (more than100%, less than 0%) Range #1 Range #2 CTRL Transmitter CPU D/A 4-20 ma AI A/D CPU AO D/A 4-20 ma Positioner A/D CPU 26 Freedom to Choose. Power to Integrate.

27 Ranging, Fieldbus Process 120 C Transmitter Range -200 to 850 C 120 C System (No range) Reading 120 C Results: Range mismatch impossible Making full use of physical measurement range of transmitter CTRL Transmitter BUS FF CPU Digital Positioner CPU FF Digital Digital FF CPU 27 Freedom to Choose. Power to Integrate.

28 Commissioning Process Fieldbus Fieldbus Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Ranging Calibrate the comm s signal? Digital signaling/communication is standardized and does not require any kind of adjustment. 28 Freedom to Choose. Power to Integrate.

29 Commissioning Process Fieldbus Fieldbus Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Ranging Calibrate the comm s signal System ranging (DCS) Not required and not reasonable, as the transmitter provides readings inclusive engineering unit. 29 Freedom to Choose. Power to Integrate.

30 Commissioning Process Fieldbus Fieldbus 30 Freedom to Choose. Power to Integrate. Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Ranging Calibrate the comm s signal System ranging (DCS) System calibration comm s signal Digital signaling/communication is standardized and does not require any kind of adjustment.

31 Commissioning Process Comparison 4-20mA Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Ranging Calibrate the 4-20mA (current drift) System ranging (DCS) System calibration 4-20mA (current drift) Fieldbus Install the devices Verify device installation Install the DCS Assigning the I/O Calibrate the sensor (sensor drift) Ranging Calibrate the comm s signal System ranging (DCS) System calibration comm s signal 31 Freedom to Choose. Power to Integrate.

32 Commissioning in Practice 80 95% of problems are installation related What are these problems? How to avoid them? How to find them if they occur? (Troubleshooting) 32 Freedom to Choose. Power to Integrate.

33 Bad wiring technique Welding, variable frequency drives (VFD), Motors, machinery: Increase of HF noise Increasing number of retransmissions Can be a combination of both Freedom to Choose. Power to Integrate.

wires (increasing resistance) Increasing number of retransmissions Signal amplitude

34 Case study: faults in operation Cable jacket stripped back too far can cause instrument malfunction: Water ingress Wires shorted to housing Corrosion Tearing wires (increasing resistance) Increasing number of retransmissions Signal amplitude rises Increase of FF noise Can be a combination of above Freedom to Choose. Power to Integrate.

Wires coming out of ferrules: Spur: Device drops off (may or may not return) Increasing number of retransmissions 35 35 Freedom to Choose.

35 Wires coming out of ferrules: Spur: Device drops off (may or may not return) Increasing number of retransmissions Freedom to Choose. Power to Integrate. Trunk: Devices drop off (may or may not return) Signal amplitude sometimes ok, sometimes high Increasing number of retransmissions

36 Bend radius too tight, Upward facing gland risks water ingress Two cables into one gland prevents sealing of gland Freedom to Choose. Power to Integrate.

37 37 37 Freedom to Choose. Power to Integrate. Corroded terminals: Increasing number of retransmissions Increase of FF noise Can be a combination of both

38 Commissioning 4-20mA Always on the critical path (may bring signal down) Manual, step-by-step procedure Labor intensive Requires Screw driver Check sheet Pencil Multimeter Scope Check one device at a time Test Report 38 Freedom to Choose. Power to Integrate.

Portable Commissioning tools for fieldbus

user interface Can store & upload data No

39 Portable Commissioning tools for fieldbus Portable tools for commissioning, monitoring, and troubleshooting. Different products on the market to suit different needs. Can connect to any spur or trunk Menu guided user interface Can store & upload data No paper needed No manual recording Check many devices at same time 39 Freedom to Choose. Power to Integrate.

40 Portable Commissioning tools Host control system Instrument Management Software (including fieldbus diagnostics) Fieldbus power supply system wiring components Controller I/O Fieldbus Hand-held Diagnostic Module 40 Freedom to Choose. Power to Integrate.

41 Fieldbus Diagnostic Modules Integrated single tool for commissioning, monitoring, and troubleshooting. Operated in the control room, usually mounted on fieldbus power supply carrier. 41 Freedom to Choose. Power to Integrate.

42 Benefits of Fieldbus in Commissioning Faster installation and checkout due to reduced wiring and bus structure Faster device troubleshooting due to dedicated portable fieldbus multimeter Faster device commissioning due to dedicated fieldbus diagnostic modules Avoids ranging problems Avoids double-addressing and addressing in general Reduces number of tools required for testing Eliminates troublesome calibration procedures All this and more leads to significant faster project commissioning. 42 Freedom to Choose. Power to Integrate.

43 Freedom to Choose. Power to Integrate. Freedom to Choose. Power to Integrate.

1.6 Configuring Intelligent Devices

1.6 Configuring Intelligent Devices J. BERGE (2003) DESIGN FEATURE RECOMMENDATIONS Use permanently connected communications infrastructure. For the HART Field Communications Protocol, use a handheld with