Stepper motor runs continuously then intermittently

Hi All,

I have a NEMA 17 connected to an Arduino Uno via a Big Easy driver. It's powered by a 12 V 8 A power supply set at 14.5 V. Running a very basic continuous rotation sketch, it rotates continuously for a few seconds on start up, then will only turn about 1/4 revolution before pausing then continuing.

Any ideas why? Clearly not a software issue.

Any help would be appreciated

ok, worked it out. Adjust the voltage potentiometer on the big easy driver and it made the motion continuous.

Its the current setting pot, not voltage, and you need to set it correctly to match
the winding current rating. What you were seeing was the chip overheating and
shutting down.

Such motor drivers control the current through the winding.

The Thread stepper motor basics may be useful

...R