After all this, I've begun to realize that you can talk and talk and talk to no end about what the code is, what one person does vs. another, what some equation tells you very generally about ampacity, etc. etc. etc... it comes down to settling with some sound advice, observing the specifications of the parts you purchase, and being sane. There is so much confusion about what the NEC says, it just blows me away. Standards are supposed to create clarity, not confusion. If the plug is rated to 20A, don't put it on a 50A breaker, if the wire says "rated to 60A" don't run 80A through it, if the motor says DC, don't plug it into an AC circuit, etc, etc, etc. I'm going with Al Patrick's advice and am going to "get to work".
Footy wrote:
formula that
conductor at
therefore