Buzzing stepper motor

Is it normal for the stepper motor to make a buzzing noise after turning down the current limit on one of the 4988 carriers?

I am using the Black Edition carrier, and I will have an extremely light load, but I need to keep the heat down.
Is it normal to hear some buzzing in the stepper motors?
Is this due to the PWM used to keep the current down from an 18V supply? I would expect this to be at a much higher frequency.

I notice this the most when the board is first enabled. After the first set of steps it will quiet down.


It is common for stepper motors to make noises while they are stepping, but I am not sure if what you are hearing is reasonable or not. Can you post a video so I can listen to what you are hearing?

Hearing more noise as the stepper motor begins to turn makes me suspect that you are commanding steps a little quicker than the stepper motor can keep up. If you ramp up to your desired speed, do you notice a difference in sound?



The noise is while the motor is sitting still. I know that there will be some noise as I step, but this is while the motor is stationary. I am unable to get a good recording of the sound, but it is in the 1-300Hz range and occurs when I first enable the driver using the sleep pin. After the first move it is much less noticeable. Manually moving the motor shaft does not make it go away, so I think it is related to the driver making the first step. Even after the step you can hear the same tone by holding the motor up to your ear, but it is much quieter than at first. At first I can hear it at arms length in my office over the heater and computers.
My first guess was that I shouldn’t be using the sleep pin, but the enable pin generates the same behavior.

My workaround of just making a step soon after enabling the motor is fine for me, I was mostly wondering if this is normal.

If a stepper motor is holding its position, it is not uncommon for it to make noise, especially when the stepper motor driver is switching the motor supply to limit the current. I suspect that the louder sound you hear happens during specific steps of the step sequencing of the motor driver; do you notice it at certain multiples of steps?