CALIBRATION
MANUAL TUNING (FUNCTION CODE 55)
I-E96-322A
4 - 7
and Table
for information on correcting the LVDT
response.
11. Calibrate the LVDT transformer before tuning the control-
ler gain. Refer to
Initial Calibration (Function Code 55)
for
the LVDT calibration procedure.
Controller Gain
To start controller tuning, the MFP module must be communi-
cating with the IMHSS03 module and the following conditions
must be met:
•
The controller gain must be set to one.
•
Demodulator gain tuning must be complete.
•
The turbine is off-line.
•
The servo valve or I/H converter (for turbine hydraulic sys-
tem) must be in the controlling position and functioning
properly.
•
The multi-function processor module has function code 55
in its configuration.
•
The block containing the calibrate mode enable specifica-
tion is set to disable (S11 = 0).
To manually tune the controller gain:
1. Enter position demands using the block (specified in S6)
containing the percent position demand. Enter values of 50%,
75%, and 90%. Observe the response of the valve at each
demand level. The valve should respond without oscillating at
each level of demand.
2. If the valve operates smoothly at all demand levels, then
increase the controller gain to the next higher value and repeat
Steps 1 and 2.
3. When the controller gain reaches a point where the valve
oscillates at any demand level, decrease the controller gain to
the next lower value. Repeat Steps 1 through 3 to verify that
the valve operates smoothly at all demand levels. This is the
correct controller gain.