We stopped using the shields and built the circuit with A4988 driver with a 1.2A 12V NEMA 17 stepper motor.
We built the circuit based on the following instructions:
We are powering the motors with a DC power supply set to 12 V. However, when we turn on the power supply and if the motor is connected the power jumps to current limiting mode drawing only 0.6 Amps at 6 V. We can't figure out why the stepper motor is drawing so much current when the power supply should be able to supply up to 30 A.
We checked to make sure the A4988 wasn't fried by measuring voltage without the motor connected (checked voltage at the 1A, 1B, 2A, 2B) and we made sure the Arduino is working as well.
The data sheet for the motor:
http://www.pbclinear.com/Download/DataSheet/Stepper-Motor-Support-Document.pdf.
Information about A4988:
http://documentation.echopen.org/CAT-daughter_board/DB-motor_control_v3/doc/pololu_a4988.pdf
Data sheet for power supply:
https://cdn.testequity.com/documents/pdf/bk/1762_datasheet.pdf
Does anyone have any ideas why motors are drawing so much current from the power supply or any idea what could be happening?
Any help would be appreciated!