Agreeing with the previous posters:
- Ya got 50A wire. You use a 50A breaker. Ditch the 60A breaker. It's not safe, it's the wrong one, period. Get the GFCI type of 50A breaker, as previous posters have noted.
- Ya got 50A breaker, 50A wire.. but that nutty NEMA14-50 is labeled, "30A". This raises weird flags. It might be a real 50A NEMA14-50, but somebody's playing silly buggers with labels. Get the actual part number (may be on the front) and manufacturer and see what ya got. If it is some bizarre 30A version of a NEMA14-50 socket, throw it out and far away and put in a real NEMA14-50.
- If it turns out to be a real NEMA14-50, check the manufacturer and report back here. I don't use this kind of socket, but there's been multiple posts that the cheaper versions of this kind of socket don't last, especially if you're plugging in/plugging out on a regular basis. If that's the case, find out what the high-quality type is, get one, and use that.
Once all this is settled, your UMC will get you 32A, that being all it's good for. If you want more current, you can get 40A with your NEMA14-50 by using a TWC with a NEMA14-50 plug on it. Or wiring it directly to that wire. That's your call and how much money you want to spend.
Sorry about the doom and gloom.. but I was right about the 60A breaker
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