It depends on your stepper voltage and max current ratings.
I believe the magic number is 20 X the steppers voltage rating, and you would need a power supply that could safely cover the max current rating of all your motors added together (although it is highly unlikely that this will ever occur, it does provide a safety margin.
Double check on that voltage info I gave you, just to be sure. Higher voltage is the best way to improve speed and torque from steppers.
No need for a variable set-up, just size it right for your steppers and make sure you have drives that can handle the voltage and current requirements.
Colin |