Author Topic: PMDX-411 Stopped outputting spindle PWM  (Read 276 times)


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PMDX-411 Stopped outputting spindle PWM
« on: July 22, 2021, 07:21:21 PM »
Well, I emailed tech support here a couple days ago and no replies so trying the forum. I have a legit (not knockoff chinese etc) PMDX-411 purchased off this site that was happily working for over a year with my CNC router through Mach4. I hadn't used the machine for a couple of months and turned everything on and all was well but I could not get the spindle to turn on. I made the mistake of assuming it was my Gecko G540 and sent it back to them on RMA and they gave it the full look over and everything was fine.

So, after getting my Gecko back I probed pin 14 with my oscilloscope (as assigned by the PMDX config in Mach4) and I've got 0 volts. No matter if spindle is on or off or what speed I command the spindle, I get 0 volts on that pin. I can see the 12.5khz watchdog/charge pump signal and all the other functions work fine. Just no 50kHz spindle PWM.

Any idea what could cause this? Like I said, I made 0 changes...just booted up one day and it didn't work. Thanks for any help or advice!!