Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set - Manual (Page 726)

Tuning a Digital or Tachless Analog System
Appendix A
A-4
The Velocity Loop
The Optimal Acceleration Curve on the following chart is your desired
servo response. This curve is determined by your machine dynamics and
the amplifier/motor combination you have selected.
Time
Velocity
Commanded Velocity
Underdampened (Velocity Proportional Gain too High)
Optimal Acceleration Curve
Overdampened (Velocity Proportional Gain too Low)
Underdampened Causes Overshoot of Commanded Velocity
Overdampened Causes Sluggish Response
The tuning procedure discussed here covers how to adjust the velocity
proportional gain and the velocity integral gain to fine tune your servo
drive system. Before you can begin adjusting these parameters, you must
complete the following tasks.
Important: This tuning procedure assumes you have already successfully
completed the system start up procedure described in chapter 14 of your
9/Series Integration and Maintenance Manual (at least up to the final
tuning portion).