I have run into a few instances with my machine where i had a motor stall that could have been disasterous if i had not been right by the machine (caused the router to plunge collet deep into the work).

Is anyone familiar with a way to monitor the motor current of a stepper (unipolar or bipolar) to cut the machine off in case of a detected stall?

I was wondreing about using a low amperage circuit breaker in series with the motor windings (assumption: current spikes when motor stall?) tied into a relay that feeds back into the limit switch connections?