[sideways]

After working for months my system stopped working suddenly, and I can't work out why!!!

I had the system connected computer>DB25 breakout>DQ860MA>motors (not using smoothstepper). I was jogging the mill table X axis (slowly) and it just stopped, and Mach3 created a "stop" error. I hit reset and tried to jog, the Mach DROs move but the motors don't (all of them). I think it's hardware, not software as I have tried another computer with Mach3 too (that WAS working as my backup computer) and also by using a smoothstepper (that WAS working) and nothing will move the motors.

Facts:

- 3 axis mill plus rotable on Nema34's, was all working well without safe speeds etc - now "not a twitch" from the motors and I haven't changed any wiring at all.
- I don't have any inputs into DB25 Mach3 at all, no switches or anything...just motor outputs.
- All three axes stopped at once mid-X-jog (no settings or hardware changed), there was no mechanical load and nothing was hot.
- I do have 5v and 0v on the DB25 breakout and on the DQ860MA driver boards, they all have green LEDs, and no red LEDs.
- I do have 48v and 0v on the driver boards.
- When I turned the system on before the motors "jumped" when the computer started, they DON'T jump any more.
- When I first turn everything now on I still can hear the motors "hissing", and there is still holding torque.
- If I unplug the motor there is a small spark and I can turn the unplugged motor freely by hand.
- When I plug the motor back in it is "notchy" to turn by hand but still easy, and there is NO HOLDING torque!!
- If I turn the system off, then back on, the holding torque returns.

What does this mean? Does it seem like the DB25 breakout card has failed? Or have the DQ860MA driver boards failed? (all DQ860MA units failing at once seems unlikely!!!)

In the DQ860MA manual I have it says "Motor doesn't run, without holding torque", then "RESET signal is effective when offline" so "Make RESET ineffective". But I can't see a "RESET" for the DQ860MQ, what might this mean?

Could the DB25 breakout be telling all the DQ860MA units to "RESET"? I don't see how though.

Any help would be great as I am in big trouble without it working, I would buy a new DB25 breakout but I'm not sure if that is the problem and they take ages to arrive from China!!!!

I have the Demo version of Mach3, I will be buying the full version once I'm happy everything is stable - might it have a time limit though? (again the backup machine hasn't had it installed long so I suspect that's not the issue)

Thanks guys! (PS MODS - I wasn't sure about putting this here or in general electronics, please feel free to move if I got it wrong)

[vegipete]

Please please please please do not plug and unplug the motor while power is turned on!

Do you have a means of testing the step/dir/enable signals at the DQ860MA drive terminals? A voltmeter would work for dir and enable, a frequency meter or scope might be necessary for the step signal.

[sideways]

We've been trying to get somewhere with a scope - so the dir signals are a high/low DC? I was still thinking in terms of pulses! 5v (and 48v from the power supplies) are already confirmed with a voltmeter.

I've got a second breakout board too now so I hope to do more test tomorrow.

What's the main downside of unplugging the motors while the drivers are enabled by the way - blowing up the drivers? (ignoring the mill movement and ignition source possibilities)

[awerby]

Yes, you probably did damage your driver by doing that. That "small spark" you noticed was its spirit departing for the next world. If you did this with all your motors, then it's most likely time for a new controller. If it was just one, then you might be able to replace that driver individually.

Andrew Werby
www.computersculpture.com

[sideways]

I accidentally unplugged a few on them a few times while building the system and it's worked flawlessly up untill they all stopped dead, it seems unlikely all the drivers would die at the same time, ever the ones that was not in use (and didn't get unplugged).

I've got a new breakout board so fingers crossed that'll solve it....although it's the new "upgraded" one everyone seems to be selling now so it's not a straight swap.