Meriam MFT 4010 Modular Calibrator_HART Communicator - Manual (Page 50)

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If the Custom Loop Test option was selected, then the display below left is shown. Select the Create
Procedure menu option to enter the Custom Loop Procedure Setup Screen shown at right below. Once this
setup is complete, selecting the Continue menu option will launch the Loop Calibration Screen.
Notes:
For conventional devices on a loop to be tested, remove the device from the loop and replace it with the
VMA0055 module connections for transmitter simulation (see the VMA0055 Manual section in the appendix
of this manual). The MFT with VMA0055 module will automatically modulate the loop current to the Set
value displayed on the Loop Calibration screen (4.000 mA in the example at left above).
For HART devices on a loop to be tested, the MFT 4010’s HART connections are made to the device on
the loop. The MFT then sends the HART commands necessary to fix the device’s analog output at the Set
value (4.000 mA in the example at left above).
At this point, the user determines the loop current received at the control room, or the value read at the
receiving device involved, and enters the value into the MFT by selecting the Entry soft key. The MFT’s
numeric entry system is used to enter the value. Press the Done soft key when satisfied with the entered value
and answer Yes to save the new data. The Error percentage between the Entered value and the Set value will
be displayed for the user’s reference. Finish documenting the loop cal point by pressing the Save soft key.
The screen will update as shown below for a 2 point loop test. Complete the second point of the test in the
same way.
Cal
Loop Test
Set: 20.000 mA
Entered: 20.000 mA
Error: 0.000 %
2 points of 2
Save Entry Abrt
Cal
Manual Cal Proc
Manual Cal
Create Procedure
Up Down Select Back
Cal
Manual Cal Proc
Continue
Show Points
LRV: 4.000 mA
URV: 20.000 mA
# upscale pts: 3
# dnscale pts: 3
Adj to Limit: 5.0
Up Down Select Back
Custom Loop Procedure
Setup Screen
Cal
Loop Test
Set: 4.000 mA
Entered: 4.000 mA
Error: 0.000 %
1 points of 2
Save Entry Abrt
Loop Calibration Screen