[mikekozura]

If who ever installed it told you it was 220 volt it's single phase but none of this really matters if for some reason you have a three phase entrance the voltage will be 208. Ac volts are Ac volts @220 you will draw 27.28 amps or @ 208 you will draw 28.85 amps in your case it dos'nt mater your using the voltage for resistance. I think double pole three phase is 208v then theres always the crazy leg. Don't worry about it either way your good. The higher the volts the less amps. Get the phase thing out of your head dude. It's all good. Now that I read over this it really dos'nt matter. As long as it's a 50amp outlet your good.