Stepper Motor setup


I am camped on DRV8825 Stepper Motor as they are employed with the ASTROEQ driver. The current is set using a VOM and a Phillps screw driver. My question pertains to NEMA 17 motors. The brand are from the StepperOnline shop.

The amps/phase =2.0

This makes the DRV8825 hot when the Vref is approximately 1.0. What I am finding is that when driving the motors (RA and DEC) at low speeds <600x within KSTARS and EKOS. Where this cuts is when fine tuning to get to a celestial object. The motors just stutter. I have one DRV8825 just quit on me. This is why I am questioning.


It sounds like you have your current limit set too high. Our DRV8825 carrier is rated for 1.5A per phase, so at 2A it is overheating and the thermal protections are kicking in. Can you reduce your current limit to 1.5A (a VREF of 0.75V), and see of that helps? If you need 2A per phase, I suggest our TB67S249FTG, TB67S128FTG or High-Power Stepper Motor Driver 36v4.

Please note, the TB67S249FTG is not able to handle the full 2A per phase continuously without additional cooling either, but with some forced airflow you might be able to get to 2A per phase.