I have an ezrouter (wood router cnc). The other day, mid program, the spindle lost rpm although it was programmed for a constant 18,500. I interrupted the program and restarted. The program started, positioned, and began the program- but did not start the spindle. Mach 3 shows the spindle turning at 18,500 rpm but it is not. My vfd shows the spindle turning- but it is not.

+The 'jog' activates the spindle at 1,800 rpm consistently.
+ At random times during testing the spindle hascome on, run up to 18,500 rpm and held it... then slows down, speeds up, stops... (it stopped doing that since, nothing but the jog button will make it turn).

Any suggestions welcome. I've got a bunch of guys fixin to be out of work unless I can get this resolved fairly quickly.

Delta VFD-B
HSD ES929 iso30