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« on: April 28, 2008, 04:56:47 AM »
Stepper motors are normally run at several times their working voltage. It does not hurt them.
If your motors are rated at 2.0amps at 6 volts, then you would be better to run them at 24 volts, or even 30v. If your driver boards only go up to 24 volts them stick to that.
The driver board SHOULD have some way to limit the current output to each motor. Each driver board, therefore needs to be set at the motor rating - 2.0amps, so the current to the motor is not exceeded.
You therefore have your answer - your power supply needs to be 24volts - capable of giving 6.0amps. You needs a capability of 6.0amps just in case all motors are drawing 2,0amps simultaneously - perhaps not likely, but possible.
Your problem will be to ensure that, when the motors are not drawing full current, the voltage on your power supply will not rise above 24 volts and therefore damage your drivers.
On my system I use 2 x 12volt batteries in series to give 24 volts and as much current as I need - without any danger of exceeding the "safe" voltage of my drives. I have just replaced two of the drives with Gecko drives which are OK up to I think it is 70 volts, so really the problem does not arise - but my third driver, for my Z axis is a 24 volt 2.5 amp drive - so I have to keep within those limits.
I charge the batteries up overnight - no problem