PMAC Quick Reference Guide Sluggish Response Cause: Too much damping or too little proportional gain Fix: Increase K P (Ix30) or decrease K D (Ix31) Overshoot and Oscillation Cause: Too little damping or too much proportional gain Fix: Decrease K P (Ix30) or increase K D (Ix31) 4. Perform a parabolic move and use the following guidelines for the selection of the appropriate I- Variables: Ideal Case The following error is reduced at minimum and is concentrated in the center, evenly along the move High vel \ FE correlation Cause: damping Fix: Increase K vel (Ix32) High vel \ FE correlation Cause: friction Fix:
Increase Integral gain (Ix33) or Friction Feedforward (Ix68) High acc \ FE correlation Cause: Integral lag Fix: Increase K aff (Ix35) High acc \ FE correlation Cause: Physical system limitations Fix: Use less sudden acceleration Negative vel \ FE correlation Cause: Too much velocity FF Fix: Decrease K vel (Ix32) High vel \ FE correlation Cause: damping and friction Fix: Increase K vel (Ix32) High acc \ FE correlation Cause: Too much acc FF Fix: Decrease K aff (Ix35) High vel\FE and acc\FEcorrelation Cause: Integral lag and friction Fix: Increase K aff (Ix35) 18 PMAC Executive Program, PEWIN