Have a Bridgeport with TNC 151B controller and the spindle doesn’t work.
All signals coming from control are good but the problem is the MTI-1 board keeps blowing fuses. We checked the board and everything visually looks OK and measuring all caps, diodes and transformer seem to measure OK. We even tried disconnecting the Spindle field and armature wires but still the fuse blows.
At this point we figure the board is bad and are looking to send it out for repair or replace it (if anyone has a source please share) but we worry that there might be a problem with another one of the boards or spindle.
Anyone have any advise on this problem??