Welcome, Matt!

I saw your post and had to step away, then came back to find Richard had already responded. I'll admit I was a touch confused by your note about "breaker not hot, wall plug not hot" which to some might mean there is no electric power.

Richard and I both kind of assumed you're working on steel, is that the case? If yes then he's spot on: set the machine for DC electrode negative and turn off anything to do with AC.

As long as you're checking connections, how's your ground?

Dave O