What is the best way to connect a 20 amp plug to a 30 amp outlet?
Easiest way to do it is to change the wall receptacle, or the plug on the compressor. You can make an adapter cord, but it is going to cost over twice as much as the first 2 fixes would. No reason to change the wire in the wall, or the breaker. Changing either, would be a waste of money. Breaker size is determined by the wire size used in the building. Having the wire over sized is a GOOD thing. Especially on a device that has very high start up draws like a compressor. The motor on a compressor, will have its own factory set thermal overload protection. Which is more than enough to protect it, and probably if you check, likely to be UL approved. (That means throughly tested).
