Why Stepper Motor Too Hot? Let’s Fix It.

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Stepper Motor Too Hot

Why Stepper Motor Too Hot? Let’s Fix It. – Today I will share my experience to solve a hot stepper motor. This was the start of the day when I just got a CNC Shield V4 keyes with a4988 driver.

After trying to code the program using Arduino, the stepper motor starts up and turns around successfully.

Surprisingly, after about 2 minutes the stepper motor turned on became very hot. When I touched the stepper motor with my hand, my skin was very sore.

Why is that? let’s see how the stepper motor works.

Why Stepper Motor Too Hot? Let's Fix It.

Causes of Stepper Motor Hot

In the general construction of a stepper motor, there are two important parts, first the stator and the second is the rotor.

The stator is the static part, that part is the coil. While the rotor is the moving part, it is the shaft.

In the stator, there are several separate windings that will be used to generate an electromagnetic field. In the rotor, there is a magnet.

When an electric current flows in a coil, an electromagnetic field is formed. If the magnetic field generated by the winding hits the same pole as the magnet in the rotor, the rotor will rotate.

This happens because the magnets will repel each other against the same poles.

If the magnetic field generated by the winding hits a pole that is different from the magnetic pole of the rotor, the rotor will be stationary because it will attract each other.

The greater the current given, the greater the magnetic field produced. This makes the stepper motor have high torque.

When a very large magnetic field is formed, lines of magnetic force will penetrate the metal (stepper motor body) so that eddy currents appear and generate heat in the body of the stepper motor.

This principle is used in electric stoves, maybe you have an electric stove, right?

How To Fix A Hot Motor

From this situation, it can be concluded that the greater the current flowing in the coil of the stepper motor, the hotter the motor body will be.

We cannot leave this state for too long, it will shorten the life of the stepper motor itself and make the stepper motor damaged.

The way to fix this is to adjust the current given to the stepper motor according to the stepper motor specifications. I am using a4988 driver, I have made an article How to Set Current Limit in A4988 Driver. You can read it here.

Hopefully this article helps you overcome the stepper motor overheating.