If the motor starts acting rough or is excessively trying to move without physically moving the input shaft. Re-check that your pins are in the correct settings and always set the amps required to the closest needed but not exceeded (ex. required 3.00A, but only having 3.14A revert from using 3.14 and go lower to 2.57A).
Also a software issue that can affect the motor is Config/MotorTunning/(x,y,z)-axis, if you are trying to push your motor to move at a faster rate by modifying the acceleration and velocity could cause your motor to fail if the settings are to high. Lastly out of those two tests, would re-check wiring for continuity lastly.
Also, even if the wiring was checked thoroughly, re-check the wiring for any chafing from wire ties or any other means of causing a short with two or more of the motor wires.
You can also try swapping the motors from another axis to determine if the cause is derived from the driver or the motor.
I disconnected the stepper motor entirely except left the yellow and blue wires tied together and the motor still made the sound when manually rotating the shaft. When I disconnected the yellow and blue wire the motor rotated smoothly again, so there must be a short inside the motor. Is there a warranty on the motors you sell?
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The X-axis stepper motor on my BlackToe suddenly started acting up. It is wired bipolar series, and was working great but then in the midst of a cutting operation the stepper started sounding rough- as though one of the phases was shorting out. However, all the connections and wires are in tact. Any ideas what would most likely cause this?