Hello, if I am using a Nema 23 from openbuilds and a PLC to control it, do I need a power supply for the driver + the stepper and a different power supply for the PLC or can I use a 24V power supply to supply both?
You can use 24v - but double check your chosen stepper driver to see if its in range for the driver. Drivers control power to the motors (fixed current setpoint, fixed coil resistance = varying voltage to honor ohms law)