Quote Originally Posted by Mad Professor View Post
Dan Brown: I have not done any more testing since after removing the damaged chip.

I have tested that all the other axis are still working using my adjustable bench power supply, but I can only run the board / motors upto 15volts on this power supply.

But at this lower voltage my current rig is very slow, max of 200mm/min, for the very short time that the board was running at 36vdc I was closer to 450mm/min rapid move, not cutting.

I will be back to testing the current sence resistor and dip switches.

When using my scope with my bench PSU I always have to use my laptop on battery, as if the laptop on mains or a PC is used I get very strange readings on the scope software, so thats something else I have to look into.
As per my thread above, on 36v the max step rate for these motors is 900steps/sec, thats 270rpm or about 500mm/min on a 2mm pitch screw.

Sounds like you have some ground loop problems. Make sure stepper PSU and scope/PC are on same power socket so they are earth referenced together. I cant use the same PC as the scope and the driver for the stepper, for the same reason...