Hello,
I have a 4th axis driven with a dc servo motor and gecko by mach 3. I can tune the positioning in mach to get an exact stop at 3600 degrees. I can repeat the command several times and it will stop right on after ten revolutions. When I give it the same command, but negative it is off by about 40 degrees on ten revs. I cannot figure out why it would be different turning the other direction. I have encoder feed back to the gecko and it does not trip so I think it is seeing the commanded position. Any ideas what may be causing this ?

Thanks,
Scott