There are many reasons why the motor rotates in one direction. You can refer to the possible reasons listed in this article to check the motor and driver to solve this problem.


1. Some faults in the motor cause the motor to rotate in one direction


1) Motor power supply failure

Stepper motors require stable power supply when working. If the voltage is insufficient or unstable, it will also cause the motor to only rotate in one direction. At this time, you need to check the power supply and confirm whether the power supply is working properly.


2) The wiring connection of the motor is wrong

Problems with the stepper motor circuit connection can also cause the motor to only rotate in one direction. Common problems include incorrect connection of signal lines and incorrect motor phase sequence connection. The solution is to check whether the line connection is correct. You can try to swap the wiring of A+&A- or B+&B- to check whether the rotation direction of the motor changes.


3) Problems with the motor itself

If there is a problem with the motor itself, it will also cause one-way rotation. Common problems include: magnetic circuit asymmetry, damaged or aged windings, failed drive circuits, etc. The solution is to check the status of the motor and replace the faulty parts in time.


4) Motor coil problem

Problems such as open circuits or short circuits in the stepper motor windings will cause the motor to only rotate in one direction. At this time, it is necessary to check whether the motor coil is normal and replace the damaged parts in time.


5) Inside the motor

There must be a certain gap between the rotor and stator in a stepper motor to allow rotation. If it jams or gets stuck while turning, it may also cause the motor to only rotate in one direction. In this case, it is necessary to clean the inside of the motor and check whether there are problems such as aging, wear, etc.


6) There is a problem with the method of controlling the motor

A. One-way pulse control

Some controllers use one-way pulse control, that is, the controller only outputs pulses in one direction, causing the motor to only rotate in one direction. At this time, the controller needs to be replaced or the control method needs to be changed.


B. The motor phase sequence is wrong

Stepper motors need to be driven in the correct phase sequence. If the drive phase sequence is wrong, the motor can only rotate in one direction. In this case, the phase sequence connection method needs to be modified to ensure the normal operation of the motor.


2. Some faults in the driver cause the motor to rotate in one direction


1) Problem with drive connector

Reinsert the driver's connector and rewire it, and check whether the motor returns to normal.

If there are other normal drives, replace the connector on the normal drive to the problematic drive and check whether the motor returns to normal.


2) Problems with drive settings

A. Check whether the drive settings are correct. Some drives support two-phase or three-phase enable signals. If the enable signal only sends one phase, the motor can only rotate in one direction. The solution is to check the drive's settings and adjust it to the correct one.


B. For some drives, you can adjust the rotation direction of the motor by dialing the dial.

So you can check whether the 5V/24V dial on the top of the driver is selected correctly. If the dial selects 5V and the input voltage is 24V, the internal components of the driver may be burned out and the motor may only rotate in one direction. Use other normal drives to cross-test and check whether the drive is normal.


3. Cable problems cause the motor to rotate in one direction

Check whether the cable is disconnected or has poor contact.

If there is another normal extension cord for the motor, try replacing it with a normal extension cord and check whether the motor returns to normal.