Thread: Drum sander causing circuit breaker to trip

Replace the C rated breaker with a D rated one. It will allow a higher startup current for a longer period without tripping.

Originally Posted by qwertyu

Got a supermax 25-50. The motor which drives the drum runs fine, but the small DC motor which drives the conveyor trips the circuit breaker. I find that if I turn the knob very slowly to turn it on and increase the speed slowly its all fine. Once its on I can adjust the speed of the conveyor up and down no problems. I figure the initial current is too high for the breaker or maybe my breaker is too sensitive? This breaker runs everything else I plug into it fine - all power tools I've ever plugged into this point and also my table saw (saw stop professional).

I notice that when I plug the supermax into another point on a different circuit/breaker, it turns on fine (dont need to do it slowly).

The breaker is: BQS DRNL-32 C20 on both circuits.

What do you guys think?

I had similar issue with my previous wide belt sander. the main motor turn on fine, but when I start the belt motor it will trip out the breaker.
The diagnosis is that the belt motor terminals has aged and terminals were touching the casing, once repaired its all good again

perhaps its your breaker? get a bigger breaker?

The circuit breaker will have been installed by a sparkie (hopefully!) and be appropriate for the circuit it's supporting. I would be unwilling to change this for a higher rated one without expert advice, as it's potentially asking for trouble.

SawStop owners have come across this issue previously, *provided* that your trip of the circuit breaker occurs only when starting that motor - and Bohdan's advice is spot on, as a D rated breaker should provide a much greater startup current.

If your circuit breaker trips at times other than initial startup, seek an electricians advice IMO.