I have an Interact l MK II with the KTK drive (Heidenhain TNC2500 Control). When starting the spindle I am getting a "Spindle Dirve Fault" alarm. I can reset and wait and sometimes get it going and it will run for a couple of hours (I work in the evening). When I first installed the machine I could start at lower RPM, but not start at much above 1000. I am running on a 20hp phase converter and I ended up installing some run capacitors and haven't had a problem for over a year. I have 240v. Is there some voltage checks/adjustments on the drive or the interface board I could check? On initial machine start up in my shop one of the capacitors burned up on the MT1-1 board. That was repaired and I have run for over a year. I have no manuals except from Heidenhain.
Thanks for any help.