1. Field Pressure Calibration & Equipment Maintenance Whitepaper
Ronit Mukerji
GMI/PTI Product Manager

2. GMI/PTI Product Manager
Presenters
Ronit Mukerji
GMI/PTI Product Manager

3. Topics

4. Topics Introduction to Pressure Sensors
Transmitters
Verification & Calibration Basics
FieldMate Basics
Unique Solutions
Applications

5. Pressure Introduction

6. Basic Physics of Pressure
What is Pressure?
It is a measure of force
One of four common plant measurements
Mathematically, pressure is expressed:
P = F / A
P = Pressure
F = Force
A = Area

7. Pressure Reference Gauge Absolute Vacuum Differential
Positive Gauge Pressure
Vacuum
Atmospheric Pressure (Sea Level)
0 psig psia
Positive Absolute Pressure
Reference
Negative Gauge Pressure
Vacuum
Reference
Absolute Zero Pressure (Perfect Vacuum)
-14.7 psig 0 psia
Reference
Reference

8. Pressure Transmitters
Absolute DP
Gauge

9. Pressure Sensor Technologies

10. Pressure Sensor Types Capacitance Silicon Resonant Piezoresistive
Typical Capacitance Pressure Sensor
Two ‘H’ shaped
bridges resonating
@ 90 kHz are located
in a silicon substrate
Capacitor Plates
Isolating Diaphragm
Sensor Plates
Fill Fluid
15-50 pf differential
Piezoresistive
Wheatstone Bridge
Diaphragm
Piezoresistor (4x)
Silicon
Pyrex Glass

11. Silicon Resonant Sensor

12. Silicon Resonant Sensor
When a D.P. is applied
Low Pressure Side
High Pressure Side
Tension
Compression
The outer sensor goes into tension (freq )
While the inner sensor goes into compression (freq )
The resultant D.P. is linear with the difference in frequency

13. Advantages of Resonant Sensor
Inherently Digital Output
Frequency Signal
No A/D Conversion Errors
Re-ranging Errors Eliminated
Large Change in Output
Excellent Resolution
Frequency Shift 40K Hz
Silicon Resonator
Minimal Hysteresis
Minimal Temperature Coefficient

14. Transmitter Overview

15. Quckly, Accurately, Reliably
Transmitter Overview
Process variable
Sensor
Convert to analog or digital signal
Transmit signal
Controller or monitor
Quckly, Accurately, Reliably

16. Transmitter Terminology
Lower Range Limit (LRL):
Minimum value that a sensor can measure.
Upper Range Limit (URL):
Maximum value that a sensor can measure.
Range:
Total pressure that the sensor can measure. (Range = URL + │LRL│)
Lower Range Value (LRV):
The lowest value that the transmitter has been adjusted to measure. This value corresponds to the 4 mA analog signal.
Upper Range Value (URV):
The highest value that the transmitter has been adjusted to measure. This value corresponds to the 20 mA analog signal.
Span:
The difference between the URV and LRV (Span = URV – LRV). Sensor have a minimum span requirement that must be considered while assigning the 4 to 20 mA analog output.
SPAN
LRV
URV N
>N
URL
LRL
4 mA
20 mA
RANGE

17. Verification and Calibration Overview

18. Calibration Basics
Sensors convert pressure, current, voltage, temperature, humidity, light, sound, etc to a quantity that can be measured by a process controller (voltage, current, or resistance)
Various types of field sensors include:
Thermocouples/RTD’s – Temperature measurement
Current Transformers – Current (mA,A) measurement
Strain Gauges – Force (applied pressure)
Photodiodes – Light
Manometers – Pressure
Microphones – Sound

19. Characterization Curve
Characterization of Sensor
Each sensor is unique; therefore it yields a unique output for a give input.
Input Pressure
Unique Sensor
Unique Output
Characterization Curve
Input Pressure
Unique Sensor
Characterization Curve
Unique

20. Sensor Readings and Scaling
Calibration Basics
Sensor Readings and Scaling
Most, if not all, transmitters have default factory settings that are may or may not be matched accurately with the quantities they are measuring
The idea is to linearize the process variable measurement range of the transmitter across its full span
For example, if a pressure sensor is rated for 2000 PSI, we’d want it to output maximum current (20 mA) when we apply that pressure to the input
For this discussion, we will focus exclusively on pressure sensors, due to their ubiquitous nature
Temperature, flow and level can all be derived from pressure

21. CA150 Multifunction Calibrator
Calibration Basics
Portable Calibrators
These calibrators are best designed for in field usage and combine accuracy with portability.
They are mostly battery operated, although some may have connections for a wall socket
They can support some of the most commonly used industrial protocols such as HART, BRAIN, ProfiBus, Modbus, and Ethernet/IP
Other features include data logging to internal memory or and external drive for offline analysis
CA150 Multifunction Calibrator
CA450 Process Multimeter

22. When and Why to Use a Calibrator
Calibration Basics
When and Why to Use a Calibrator
A calibrator is a type of instrument that functions both as a sourcing and a sinking device. Some of the most commonly encountered types of calibrators measure:
Temperature
Voltage/Current
Power
Pressure
Resistance
Their function is to verify sensor output by producing a stimulus (either current or voltage) and verify the reading of the transducer under test

23. Calibration Basics
For example, A technician may want to verify that his or her temperature controller is displaying the proper output (in degrees C or F) based on thermocouple type
A Temperature calibrator, which, at its core, is a highly precise DC voltage source that can output a wide range of voltages for different thermocouple types can be used for this purpose
The calibrator’s output would then be used to adjust the sensitivity or verify the accuracy of a controller

24. Calibration – Why it is important
Calibration Basics
Calibration – Why it is important
All test and measurement devices come with a certain accuracy as per specifications
Over time, these instruments degrade due to normal wear and tear, as well as due to exposure to hazardous environments
Periodic maintenance (anywhere from monthly to annually) is thus essential to making sure these instruments maintain their reliability
At its core, calibration involves adjusting the tolerance levels of a measuring device against a known reference, so the two are in sync

25. As Found vs As Left Calibration
Calibration Basics
As Found vs As Left Calibration
There are two commonly used types of calibration data available to manufacturers and end users of field instruments
As Found data refers to the performance of the instrument in its latest state.
For example, a company may have a pressure transmitter in a refinery for a year, and would like to know if the device is out of tolerance.
He would then run through his calibration procedures to verify proper functionality.
As Left data refers to the performance of the instrument after adjustment.
If the As Found tests passed successfully, this step would not be necessary, or would only need minor adjustment

26. Calibration vs Verification
Although the terms are sometimes used interchangeably, it is important to note that they are two different processes
Calibration is used to determine what correction is needed for an instrument to meet its rated settings
Verification determines the percentage error of the instrument’s readings relative to a maximum percentage error the end user is willing to accept
I.e., a 2% error on a verification test with a maximum tolerance of 1% would be a “NO-PASS”

27. Pressure transmitter verification involves
Choosing a span around which to linearize the transmitter 1
This need not necessarily be the maximum specifications of the unit, and often times is not
As mentioned earlier, this is the (URV – LRV)
Linearization involves the transmitter outputting maximum current (20mA) at the URV and 4mA at the LRV, with 12mA corresponding the average of the URV and LRV

28. Verification
Comparing the measured value of the transmitter against a known reference point – A pressure calibrator 2
The rule of thumb is to have a calibrator which is at least four times as accurate as the unit under test
For example, if our transmitter is rated for 0.04% of reading, we would want a pressure calibrator that has at least 0.01% accuracy
First an As Found calibration is performed at predetermined tolerance levels
Tolerance levels are specified in percentages, which then correlate to a mA deviation limit
Yokogawa calculates this as ±((100% value of the measurement function – 0% value of the measurement function) × tolerance setting / 100)

29. Verification
So if we use 4mA as our low range, 20 mA as the upper range, with a 1% tolerance, our threshold for pass/fail would be ±(20 mA – 4 mA)×0.01/100 = ± mA
Thus, if we are calibrating the URV at 1% tolerance, we should expect to get a reading from the transmitter between mA and mA
If the unit passes the As Found test, no further calibration is necessary

30. If the unit does not pass the As Found test
Verification
If the unit does not pass the As Found test
We then perform an adjustment
This involves changing the URV and LRV parameters on the transmitter to match what is being read on the calibrator
I.E., if our span is PSI, we’d want the transmitter to output 20mA when the calibrator is reading 2000 PSI, and 4 mA when it is reading 0 PSI
We then do an As Left Calibration in a similar fashion as the As Found
If adjustments were done properly in the previous step, we should see the transmitter reacting more similarly to the calibrator

31. Verification
Once the As Left calibration process is finished, it is typical to generate a calibration report which details
All tests performed on the unit
The results (Pass/Fail) of each test and the margin by which the test results differed from the expected results
The model and serial number of the UUT
The date/time the tests occurred
The pressure ranges and response times of each test

32. Verification Device Information Callibration Information: As Found:
Device Tag
Model
EJX110A
Serial No
91H336726
Product Date
1900/00/00
Loop Name
Pressure Test
Press. Range
0.00 – kPa
Output Range
4.00 – mA
Dsplay Range
0.0 – 100.0%
Tolerance
±1%
Callibration Date
Callibration Model
CA700
Callibration Serial
91PA10134
Generated by FieldMate Yokogawa Electric Corporation
As Found:
Target data
Measured data
Input
Output
Error
Judge
kPa mA %
0.000
4.000
-0.080
4.400
2.58%
FAIL
50.000
12.000
49.440
11.886
-0.16%
PASS
20.000
19.955
-0.32%
Comment
As Left:
Target data
Measured data
Input
Output
Error
Judge
kPa mA %
0.000
4.000
0.040
4.010
0.02%
PASS
50.000
12.000
50.990
12.174
0.09%
20.000
20.142
0.12%
Comment

33. CA700
The Yokogawa CA700 Portable Pressure Calibrator uses the same DPharp sensor technology as our EJA-E and EJX-A series pressure transmitters. It provides an accurate and efficient calibration and verification tool for any pressure transmitter or other type of field device.

34. PM PSI Module
Due to high demand in the US market to calibrate larger pressure ranges, Yokogawa released the PM PSI (16 MPa) module
Effectively extends the calibration range of the CA700, while still maintaining the same basic accuracy of 0.01% of reading
This unit plugs into the top of the
CA700 via a connection cable that converts the measured pressure to digital data. CA700’s with firmware version earlier than 1.10 will need to be updated to 1.10 to communicate with this unit
112 (W) × 75 (H) × 148 (D) mm
Approx.1.2Kg

35. FieldMate Overview

36. What is FieldMate?? Field Device Configuration and Management Tool
Portable PC Based
One Tool for All Instruments (Regardless of Comm. Protocol or Manufacturer)

37. Unable to edit its test pattern
Differences in FieldMate versions
Lite Edition vs Full Function Edition
Functionality
FieldMate
Remark
Lite Edition
Full Function Edition
FieldMate recording the information of the device connected in the past
(Number of Device Maintenance Information)
7 Devices
500 Devices
FieldMate Lite Edition does not support importing/exporting function.
FieldMate showing 10 Typical parameters on Home Screen
(Segment Viewer)
Not Selectable
Selectable
FieldMate conducting “Input Loop Check” based on its test pattern
Unable to edit its test pattern
Editable test pattern
Report function is limited (Max. only 7 devices)
FieldMate generating the report of parameter comparison between past and current one
No support
Support

38. FieldMate Communication
FieldMate is a single tool which supports device configuration of multiple vendors and leading industry standard communication protocols.

39. FieldMate HART Hardware Setup
HART/BRAIN EJA/EJX Pressure Transmitter
24 VDC Power Supply
Load Resistor (250Ω)
USB Modem (HART/BRAIN)
SUPPLY CHECK
USB FieldMate MODEM
EJA
USB
Load Resistor
PC/FieldMate
No porlarity + -
24VDC
Power Unit

40. FieldMate Maintenance Features
Home screen (New Interface of Segment Viewer)
Conduct frequently used functions from Home Screen 1
Device Icon
Yokogawa Device only
Device Status
Color coded status of online device
Typical Parameters
10 frequently used parameters can be selected by user
Memo, Photo, Configuration Tool
Latest device appearance
Device Configuration from Action button
Device Info.
Tag, Vendor, etc.
Frequently used function
Last conducted data is also shown 2 1 3 4 2 3 6 4 5 5 6

41. FieldMate Maintenance Features
Home screen (New Interface of Segment Viewer)
Conduct frequently used functions from Home Screen
Multi protocol support
Users do not usually change the communication protocol, hence this function is not shown as default. From this button, show and change the communication protocol.

42. FieldMate Maintenance Features
Example: User’s work flow for Device Installation
Configuration & Parameter Check
Zero Adjustment
Calibration Check
(if users want)
Installation of Devices
Zero Adjustment
Loop Check
Work Report
Home screen

43. New Features for R3.03 c FieldMate
CA700 with PM100 Calibration Procedure
Link with Pressure calibrator expands device maintenance and management capability
Trend Data and Alarm List History
Selected data are displayed and stored every time on its connection
BT200 displayed
New look and feel

44. Field Equipment Maintenance
New Features for R3.03 c
Field Equipment Maintenance
USB cable
Measurement Leads
FieldMate modem
Air tube
Pressure transmitter
Pressure pump

45. Field Mate Core Features Field Mate Additional Features
Review of Field Mate
BACKGROUND
Configure the Field Device parameters to fit a users’ process and to bring out the Field Device performance, which in turn will help to optimize facilities operations.
Field Mate Core Features
Provide better screen an onscreen configuration guides to ensure the efficient device configuration. Field Mate supports a dedicated configuration tool for Yokogawa devices.
Support device configuration of multiple vendors and leading industry standard communication protocols.
Field Mate Additional Features
Generate the reports by only one click
Save the additional information about a device condition
Share Maintenance info with PRM for Total Asset Management

46. Applications

47. Applications Maintenance Recalibration Flow Measurement
Filter Measurement

48. Thank you for your attention!