Delta RMC101 - Manual (Page 39)

Setup Details 2.2
Starting Up the RMC 2-11
slowly increasing it and making moves. If the system begins to oscillate, decrease the gain.
5. Adjust the Feed Forwards
In torque motor applications, feed forward parameters (Extend Feed Forward and Retract Feed
Forward) often do not require high values. Adjust these parameters by making a long move
without any oscillation or overdrive. Then issue the Set Feed Forward command. This command
will automatically adjust the Feed Forward parameter for the direction of that move.
6. Adjust the Integral Gain
The Integral Gain is helpful for maintaining position. It will not significantly affect tracking during
short, fast moves. Increase the Integral Gain until the system starts oscillating, then back it down
some. Motors may require a high Integral Gain.
7. Readjust the Differential Gain
Differential Gain tends to dampen out oscillations and help the axis track during acceleration and
deceleration. This will positively affect short, fast moves.
Important: If you increase the Differential Gain, you may be able to increase the Proportional
Gain somewhat without causing the system to oscillate.
If the drive output during the constant velocity portion of the move is smooth, the Differential Gain
is perhaps not set high enough. The drive output may look "fuzzy." This indicates that the drive is
responding to the minute errors of the axis. Note that not all systems allow the differential gain to
be set high enough for the drive to be "fuzzy".
A disadvantage of Differential Gain is that it amplifies position measurement noise. If there is too
much noise or the gain is too high, this can cause the system to chatter or oscillate.
8. Adjust the Acceleration Feed Forwards
The Acceleration Feed Forward terms help minimize errors during acceleration and deceleration.
Increase the Extend and Retract Acceleration Feed Forward terms until the errors disappear.
9. Increase System Speed
Gradually increase the Speed and Acceleration values while making long moves. Look for
following errors, overshoot, or oscillations.
• If an overdrive error occurs, there is not enough drive capacity to drive the axis at the
requested Speed or Acceleration. Should this occur, reduce the Speed and/or Acceleration
and Deceleration.
• If a following error occurs during acceleration and deceleration and adjusting the Gains and
Feed Forwards does not help, the Acceleration and Deceleration ramps are too steep for
the response of the system.
• Should the system seem a little sloppy, try adjusting the Proportional Gain.