GE AF-650 GP Programming Manual page 174

PI-35 Process PID Differentiation Time
Range:
0.00 s* [0.00 - 10.00 s]
PI-36 Process PID Diff. Gain Limit
Range:
5.0* [1.0 - 50.0]
PI-38 Process PID Feed Forward Factor
Range:
0 %* [0 - 500 %]
PI-39 On Reference Bandwidth
Range:
5 %* [0 - 200 %]
Function:
Enter the PID differentiation time. The differentiator does not react to a constant error, but provides a
gain only when the error changes. The shorter the PID differentiation time, the stronger the gain from the
differentiator.
Function:
Enter a limit for the differentiator gain (DG). If there is no limit, the DG will increase when there are fast
changes. Limit the DG to obtain a pure differentiator gain at slow changes and a constant differentiator
gain where fast changes occur.
Function:
Enter the PID feed forward (FF) factor. The FF factor sends a constant fraction of the reference signal to
bypass the PID control, so the PID control only affects the remaining fraction of the control signal. Any
change to this parameter will thus affect the motor speed. When the FF factor is activated it provides less
overshoot, and high dynamics when changing the set point. par. PI-38 Process PID Feed Forward Factor
is active when par. H-40 Configuration Mode is set to [3] Process.
Function:
Enter the On Reference bandwidth. When the PID Control Error (the difference between the reference and
the feedback) is less than the set value of this parameter the On Reference status bit is high, i.e. =1.
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