AMC drive tuning

I tried grounding. Still same problem.
One other observation is that when I power off the drives, the motors drift in the direction of correction. This is still with p0.

I just swapped tach feedback and got runaway as expected. Flipped dip switch on drive to reverse logic, same runaway. Swapped motor leads, no ruaway as expected, toggeld dip sw 7 doesnt seem to do anything.
The fighting back on the handwheel is switched now, telling me its drive related.
Im really stuck now....

I was working off the suggested pot setting on the drive. I totally overlooked the reference gain pot! Getting back on track now. Turning it down to mid range is giving me the locked symmetry I was after. Thank you all for your help. Im sure ill have more qestions now that I can actually move on to tuning.

Ahh, If you can disconnect the motor from their linear axis you should be able to
adjust the reference gain so you get full speed (say 20% more than LinuxCNC limits)
with a 10V input (either from the drive itself or by setting a 7I77 analog output to 10V)
and then measuring the speed via the encoder velocity pin

Ahh, If you can disconnect the motor from their linear axis you should be able to
adjust the reference gain so you get full speed (say 20% more than LinuxCNC limits)
with a 10V input (either from the drive itself or by setting a 7I77 analog output to 10V)
and then measuring the speed via the encoder velocity pin

Thanks for the suggestion. Unfortunately the encoders are not on the motor. XY are linear on the table and Z rotory on the screw.

(either from the drive itself or by setting a 7I77 analog output to 10V)

To test, I was trying setp hm2_5i25.0.7i77.0.1.analogout1-maxlim 3.0 in the hal configurator under test hal command. I was getting argument errors. What's the right approach again to test analog 10v out via linuxcnc? I got the belt removed and want to confirm my actual rpm on the motor and will be using separate rpm gage as the encoder is not on the motor shaft. This is still in regard of adjusting input gain pot on the drive.

Also, in the Hal file, do the setp pid.x.error-previous-target true have to be off for tuning only then turned back on after? Are they no longer needed?

setp hm2_5i25.0.7i77.0.1.analogout1-maxlim 3.0

should work because its a parameter and not driven by a signal

setp hm2_5i25.0.7i77.0.1.analogout1 2

Will fail because the pin hm2_5i25.0.7i77.0.1.analogout1 is driven by
a signal, but you can set it with:

unlinkp hm2_5i25.0.7i77.0.1.analogout1 #this disconnects the pin from the signal that is driving it)
setp hm2_5i25.0.7i77.0.1.analogout1 2

(note that you have disconnected feedback at this point so expect uncontrolled motion)

I tried setp hm2_5i25.0.7i77.0.1.analogout1-maxlim 3.0 again and didn't give arguments this time. I must have had a syntax error before.
Unfortunately with the above set and executed I don't get movement. The drives are enabled, keyboard jog works. What am I missing or doing wrong?

setp hm2_5i25.0.7i77.0.1.analogout1-maxlim 3.0

would just change the analog out scaling, not output any voltage

setp hm2_5i25.0.7i77.0.1.analogout1 1

would output 3.33V (assuming the scale above = 3 for full scale)

Thanks PCW, I'll give it another try tomorrow. For some reason, I get myself confused with the ini values. In case I get it wrong, If I have a value of 10 set for max_output, can you confirm that the 7i77 will not output above +/-10v? Am I understanding this correctly? My drives can take 15v max and want to make sure nothing gets scale close to that.