[ccarlsen]

Hello everyone,

So as the title says I am experiencing overflow/underflow errors on any axis I try to move. Nothing moves at all, even during the homing sequence. I replaced and updated the motherboard and software in a hope that it was a bug there (plus the machine would just lock up (even mid cut) from time to time and was due for an upgrade), but no joy.

I have been able to move the axis with the spindle off if I remove the e-stop relay, which is what led me to believe it was a computer bug before. I replaced the relay unit as well, but still no effect.

Other than that, I have yet to find anything wrong with this machine.

Any suggestions?

[ccarlsen]

I ran PFM.exe in DOS and everything checked out. I took out both BOB boards and gave them a good cleaning as well, but no dice. I will be swapping the BMDC with another machine tomorrow and checking that. If that yields no results, I will be doing a full calibration of the motor controllers and eventually just ripping everything out of the backpack and checking it.

If it is the BMDC board, I will be replacing every non-custom chip I can get a hold of on it.

[ccarlsen]

BMDC card checks out, no problem there.

I found the reason removing the relay works; the motor controllers are set to see an external error when a logic HIGH is issued, not low. This works with the way the relay is wired, causing it to pull those lines high when the coil is unpowered. So there is a problem somewhere else.

[ccarlsen]

Solved.

Check fuse 8, it powers the relay logic.