Quote Originally Posted by Doddy View Post
Just a point of sanity - that board has no opto-isolated outputs to drive the stepper driver (which will have) - the buffer devices - 74HC series has a rise/fall time measured in 10's of nano-seconds and current source/sink in the order of 35mA - that's NOT the problem here.
That's a good point.
Only optos on the inputs.
I'm pointing to the 48v psu.
Might turn out he's trying to run 2* 86's on a single 350w.
Not happening.

Prev user prob had same problem.