Stepper motor current consumption

Support Motor controllers/drivers and motors
1

Hello,

I am working on an automatic pet feeder project. This project utilizies the drv8825 to drive my NEMA 17 42cNm which is connected to a worm shaft axis. The worm shaft axis rotates the dry feed and pushes them out of the container. Sometimes a blockage occurs, wherein the dry feed gets stuck between the container and the worm shaft axis. When this happens my motor stutters because the feeding operation is taking place. the motor only stops stuttering when feeding is done, but most of the time the blockade doesnt get cleared.

My question is how can I measure or find out how much current is being drawn from each phase or both phases or from the motor driver; during the stuttering phase. what are the consequences for my motor and driver I if dont fix this problem?

Thank you in advance

2

Hello.

Stepper motors do not draw more current with higher applied loads like brushed DC motors, and missing steps like that generally won’t damage the motor or driver, so monitoring the current through the coils likely won’t be a practical way to detect when the stepper motor is stuck. Is there a different reason you want to measure the coil current?

You might consider using some kind of sensor such as an encoder to detect that it is rotating when you expect it to or do something less elegant like periodically driving it backwards to try to clear a potential blockage.

Brandon