Sun Jan 07, 2018 12:22 pm by cornbinder89
You have a number of options, If you only have one thing that you are really going to "use" then I would stick with single phase. You can make a phase convertor out of a 3 phase motor that you "idle" by running it on single phase no load, and connecting the three phase load in parallel with it. You will need to add a run capacitor across two of the leads to get the motor to start, You can also buy a static convertor or the aforementioned FVD.
It seams silly to pay year around for 3 phase only to run a compressor. The thing is used three phase equipment is dirt cheap, because shop are unlikely to want to mess around with used stuff, and most hobby shops don't have 3 phase.
If you run a three phase motor on single, you loose a bit of hp, so if the motor in question is heavly loaded you might want to consider the FVD method sized to match the full load current of the motor in question.
I have 125 amps of single phase available in my barn, so haven't the need of 3 phase yet, but I bought a 1940 army air core 62.5 KVA generator for $600 so I also can have 125 amps of 220 three phase if I need it, whether I can afford to feed the generator is another question? It burns 5 gal/hr of gasoline, and I would convert to LP as I wouldn''t want to store that much gasoline on the property.
I did use to it to power a welder once, it never even noticed that load!