Archived from the Tools In Action forum (Dewalt). This thread is read-only.
My DWS779 miter saw trips the 20 amp breaker a lot. I’ve tested it at startup and the initial amp reading is 55 to 60 amps at start. Then quickly settles to 13 to 15 amp. I’m sure this is the cause Is this initial spike at startup normal? Does it seem high? The saw has a warranty. Getting Dewalt customer service on the line to discuss this, has been impossible for me.
Welcome to the forum.
Every electrical motor presents a largely inductive load to the source providing power.
One characteristic of an inductive load is that the current does not want to change instantly. An inductive load does instead permit “instant” voltage changes.
All that being said, it is very unusual for a motor to experience a startup current surge, even/especially a large motor.
IMO, a more likely source for the problem is a defective breaker, insufficient wire gauge from the panel to the tool (in this case a 20A breaker should be 12 AWG), poor connection(s) from source to load or multiple poor connections from source to load.
My first step suggestion is to swap the existing 20A breaker for a new part to see what happens.
An inspection of the wiring condition wouldn’t hurt either.