The correct driver for the NEMA 34 Stepper Motor (651 oz-in 1/2" single shaft) 5.5 Amps is the following driver that can allow up to 5.6 amps of current.

https://www.buildyourcnc.com/item/electronicsAndMotors-stepper-driver-3!0a

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[55] What is correct driver for this motor

Yes, we can supply this as a dual shaft motor, you can email us after the purchase so we can change the order to reflect the dual shaft requirement.

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[55] Does this motor come in dual shaft?

Can you tell me the part number of the motor?

An easy way to determine the coil pairs for 4 wire stepper motors (open-loop stepper motors only) is to connect two of the wires and try to spin the motor by hand. If the motor shaft turns with difficulty, those two wires belong to one of the coils. You can insert those two wires into the A+ and A- and the other two wires to B+ and B-. If the motor spins in the wrong direction, then you can either swap the two pairs at the driver, or toggle the "DIR active low" or "DIR Invert" in the CNC control software for that axis.

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[55] My Nema 34 motor has different wiring colors, black blue red green instead of what is shown here. How do I wire it.