I was wondering if it is possible to tap into the signal either on the low power side (between motion controller and the stepper motor driver) or on the high power side (between the stepper motor driver and the step motor itself).
I have a 4 axis motion controller, from which I am trying to take the signal off of the Z axis and use it to drive a optocoupler that would be in Darlington configuration with a bigger transistor to drive a relay.
Stepper motor is a big one Leadshine 86HS120 High Performance 2-Phase NEMA 34 Hybrid Stepper Motor, 70 V / 5-7 A.
Is this "tap" going to degrade the signal in any way, and if not - what should be required (I was thinking about some rectification and smoothing circuit to drive the optocoupler LED).
Excuse for my lack of knowledge in this field and please share your thoughts. Any word of advice is appreciated. Thank you.
Before anything, thank you everyone for engaging. Secondly, I see your point - so I am including the details for easier understanding.
This is a commercially made industrial laser cutting machine. It uses two axes (X, Y) for laser cutting head and Z axis for moving the belt "bed" underneath the material (textile material that is fed from a spool on the right side of the machine, goes trough the machine and out the left side).
There is an additional table to the left side of the machine, that needs to rotate its belt when the belt inside the machine rotates, so the cut material flows out without wrinkling.
This side table is the issue. It has its relay that is connected to PIN 6 of the general purposes "OUT" port of the controller, and should get a command to start the side table belt when Z axis is engaged. But it does not - and the manufacturer is unable to debug it for a long time.
Thus a need for alternative solution arised from. To make a circuit that would take Z axis signal and trigger a relay, bypassing the port "OUT6".
Controller model is AMC6340, and the driver model is DM856.