We've been runnning this table for 2 years in a production shop with no issue until now. In the middle of a job the other day the G540 faulted, we quickly diagnosed it to the A drive (slaved to Y) in the G540 (it was noticably burned and we thought it shorted from metal dust since the controller was REAL dirty inside). I removed the A drive from the G540 and it came back to life and we limped along driving the gantry from one side. I bought I new G540 (cheaper to buy one and get extra parts than to buy a new 250 driver) and we installed it today. It quickly went to fault again. We swapped all the cables and ran all the steppers on other drives to eliminate a cable or stepper problem with no change we desided to swap drives around in the G540 to see if the issue followed the A driver but it didnt.
I said all that to say this.....the problem has to be within Mach 3. If I disable the slave drive we don't get a fault and if I enable it and leave the stepper unplugged still no fault but once I plug in the A its fine until I try to jog the table then it instantly faults and it will do this on every combination of cable, stepper and driver.