New build stepper help

[JAZZCNC]

Jazz - - Thanks, the steppers are not fitted to the machine yet, and I am confident it is not a resonance problem as that was my trade. Hand held the steppers are clearly
missing steps. The axis is jumping every 1/2 to 1 every one revolution. It increases or decreases in proportion to the velocity setting.
Rod

Ok well one thing I've seen before on cheap drives is the pulse edge only works one way so to speak and if the polarity is wrong then they do weird shit.!! So try changing the active low and see if it affects anything.!

Other than that then it's down to either wrong phase wiring, bad PP cable or Poor low power PP port or BOB.!! Have you measured the voltage coming out the PP and the BOB.?

Presume you have tried on different drive and motor to eliminate a bad one.!

[Leadhead]

Jazz - yes tried changing active low.
Will check phases, voltages and 5v supplies in the morning. Too pissed with it right now!!