View Full Version : 3 phase circuit, wire size.

Larry Fox
02-14-2013, 3:08 PM
I have a quick question about wire size for a 3-phase circuit. The size of the breaker in the 3-phase panel is 20A. Does it work the same way as single-phase in that I can run #12 for this circuit or does the fact that it is 3-phase change things significantly? It is a relatively short run (< 50') so I don't think I need to worry about voltage drop and all that.

I am likely to run it in conduit so we are most likely talking about #12 stranded conductors here as opposed to a piece of romex (if that matters).

Thanks in advance for your time.

John Lanciani
02-14-2013, 3:31 PM
Amps are amps, #12 is appropriate for the breaker size and distance to load.

Jim Tabor
02-15-2013, 9:46 AM
In conduit I would use #12 TW, THW or THHN for a 20Amp circuit.