I have a recently purchased ShapeOko2 , I have decided to upgrade it with NEMA 23 motors (along with a significant size increase) and am using G540 4-Axis Digital Step Drive to control with Mach 3, I am very familiar with the mechanical aspects of this upgrade and the functionality; however, the electrical end is a bit hazy. My question is what power supply will i need to run the stepper motors? I have looked around a bit but an not clear if I can buy an over rated power supply or if it needs to have the correct current and voltage.
You have to pick the right voltage, but you can overrate the current. The system will only pull as much current as it needs. You could probably run up to 48VDC on a typical NEMA 23 motor. An 8A to 10A power supply would probably work fine. I might back off the full current of the motors a little when you set them up. The motors and the G540 will run cooler and last longer.
Benjamin, these motors can run on a range of voltage. For bets performance you need to choose a specific voltage which is generally mentioned in its datasheet along with the required current that will be required. In case of motors there always are some graphs in the datasheet which tell you how voltage and current impact the performance. As suggested, at 48V, 10A will be required, higher the voltage, lesser the current required within its boundary conditions that is.