GE SCR Fired Drive

[wescanjeremy]

Hi Folks,
I'm new to this forum and need some help...
I'm trying to tune an old GE Amplifier on a CM56 cutting table. We have recently installed a new CNC controller and I cannot seem to get the positional loop gain high than 0.2 without oscillation of the machine.
Typically we would be able to get the gain up to about 2.0
GE drive is SCR fired (10ms), 100:1 overall gear ratio, outboard 1000 edge encoders, current traverse speed of 120 in/min
Our controller is a PA CNC with digital to analog interface.

Any help would be appreciated
Cheers, Jeremy

[vger]

Could be the new controller has a higher output level based on position error. By PA CNC I am assuming you mean Power Automation, correct? What was the old controller? I know on the controller I have there are configuration parameters that set how much output the D/A has based on the error count. If your old controller gave you .01 V output with a 1 count position error and the new one gives you .1 V.....

Hope you get it working
Steve