Travel Calibration; Check Valve Actions - GE FVP110 Maintenance Manual

Travel Calibration

Normally, control parameters need not be readjusted after auto tuning. If there is a
problem, see "Troubleshooting" on page 175. To carry out fine adjustments of the
zero-point and span settings, perform the travel calibration.
Travel Calibration
If the full stroke of the valve is too large for the maximum required flow rate, you can
change the span of the travel by carrying out a travel calibration:
1. Vary the value of FINAL_VALUE.value to move the stem and adjust the stem to the
desired point for the 100% position.
2. Write 3 to TRAVEL_CALIB_EXEC. This changes the span while leaving the zero
point unchanged.
TRAVEL_CALIB_EXEC:
❑
1 = off
❑
2 = 0%-point calibration (no change to span)
❑
3 = span calibration (no change to 0% point)
❑
4 = 50%- point calibration (no change to either span or 0% point)
The result of the travel calibration is written to TRAVEL_CALIB_RESULT.

Check Valve Actions

After carrying out auto tuning, check step responses by changing the value of the
transducer block's final valve position setpoint, FINAL_VALUE.value. Also, check
whether the valve acts correctly over the 0-100% position range.
Only when the target mode's in both the AO and transducer
NOTE
blocks are O/S, can FINAL_VALUE.value be written.
Only when the target mode is in MODE_BLK parameters in
NOTE
both the AO and transducer blocks are O/S, can
FINAL_VALUE.value be written.
It is not usually necessary to readjust the control parameters
after auto tuning. However, when using the Double Acting
Type, or if the expected response characteristics cannot be
obtained using auto tuning, either conduct manual tuning,
as in "Manual Tuning Guideline" on page 253 or refer to
"Troubleshooting AutoTuning" on page 181.
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Setup