We were talking about this yesterday, in a different thread. You need to find drivers that will handle 2 amps to drive the NEMA 17 motors, and the one that drives the NEMA 23 will have to handle 4.2 amps. The power supply that feeds them will have to be able to supply the sum of all the amperage that any motors running at the same time will draw.

The nameplate voltages don't have much to do with the voltages that they need to run optimally. That's determined by the inductance of the motors, which you haven't told us about. The square root of their inductance times 32 is the voltage you want to supply your motors. If that's higher than your drivers will tolerate, you either need to get different drivers, rethink your choice of motors, or resign yourself to speeds that fall short of the motors' true capability.

Andrew Werby
www.computersculpture.com