----- Original Message -----
From: "Seth Mattinen" <sethm@rollernet.us>
On 3/19/14, 10:21, Jay Ashworth wrote:
It is exactly that: no one says you*can't* wire a 20A branch circuit with #10.
It is even*possible*, though unlikely, that if you did so, you wouldn't have to derate it to 80%. I would have to reread the Code to be sure.
Well, I'd say it's pretty likely. However highly unlikely to be code-worthy of slapping on a 30A breaker in place of a 20.
Well, the situation were were discussing was replacing 30A CB <--> 10 AWG <--> L6-30 with 20A CB <--> 10 AWG <--> L6-20 and as I was reminded, you'd still have to derate that unless the CB was magnetic. And you can't leave the breaker at 30, cause then the attached 20A single device isn't protected properly by it. So I was worng on the derating. Cheers, -- jra -- Jay R. Ashworth Baylink jra@baylink.com Designer The Things I Think RFC 2100 Ashworth & Associates http://www.bcp38.info 2000 Land Rover DII St Petersburg FL USA BCP38: Ask For It By Name! +1 727 647 1274