Rockwell Automation 57C422B 2 Axis Servo Module - Manual (Page 90)

5-4 2-Axis Servo Module M/N 57C422B
4. Next, adjust the velocity gain. Continue to increase the
gain and observe the motor shaft. Ideally, the shaft
should regulate with very little noise or vibration. When
the shaft begins to vibrate, reduce the gain until the shaft
becomes relatively quiet.
Run the drive in the velocity mode at half of top speed.
The velocity error should be nearly zero (indicated in
register 81). Stop the drive. When the drive is stopped, it
should stop smoothly and cleanly.
5. Adjust the final value of the proportional gain. Continue
to increase the gain and observe the motor shaft. Ideally,
the shaft should regulate with very little noise or
vibration. When the shaft begins to vibrate, reduce the
gain until the shaft becomes relatively quiet.
Run the drive in the velocity mode at half of top speed.
The velocity error should be nearly zero (indicated in
register 81). Stop the drive. When the drive is stopped, it
should stop smoothly and cleanly.
6. Start with an integral gain of 10 and observe the motor’s
response as you attempt to make small incremental
moves. The integral gain will enable the shaft to hold a
rest position with zero error. A gain that is too large will
cause instability.
7. If you are using a servo drive that expects a velocity
reference and it contains an integrator in its a velocity
loop, the feedforward gain should be set at zero.
For all other drives, start with a gain of zero and run the
axis at or near its maximum velocity. Read the following
error (indicated in register 80). Increase the gain until the
following error as small as possible without going
negative.
8. Set the following error and velocity error to reasonable
values for your application.