look at the electrical connections or the diagram on the electric motor. A single phase motor would only require 2 leads. L1, L2, and a ground giving you single phase 240 volts. A 3 phase motor would have 3 leads plus a ground. A motor on a 120 gallon non upright unit usually requires 208/230 3 phase power as most of these are a 10hp unit. Or, I do believe they make one in a 460v 3 phase configuration. If you've got 3 phase accessible, I'd do it. I wouldn't try to do any phase converting on these. Don't ask me how I know........ Sandblasting with a compressor like this makes it a breeze. Or, if your into port and polishing, you'll be glad you went with one like this.