RE: [CAD_CAM_EDM_DRO] Basic stepper control question

I would guess that the 50 clicks on a 200-step motor is due to residual
magnetism of the field core. The iron has some hysteresis (which can be a
significant source of heat at high step rates), so it is unlikely to have
*absolutely no* field when all current it off.
In particular, I would expect it to retain a small amount of the last
current-generated field, so you may find that these 50 clicks move each time you
run the motor.

There is also the question of what you mean by "kill all the current" to the
motors. As an example, when I shut down my Camtronics 5Amp drivers on my
sherline mill, first I flip a switch which disables all the motor drivers (at
this point the handwheels can be turned freely). Then I turn off the main power
switch; invariably I hear the steppers jump a tiny bit. I suspect that the +5V
supply is shutting off faster than the +35V motor current supply, and as a
result the motors get just a little jolt of current.

So I guess one question is: is the motor current being shut off just by
disabling the driver with some sort of control input, or is the whole power
supply for the stepper driver being shut down?
-Kevin