Sheldon UM-56-P

Dual voltage 3-phase motors aren't uncommon. However, the low voltage connection would almost certainly be 208 to 230 volt and the high voltage 440 to 460. Actual 120 volts 3-phase isn't impossible to make either power or motor but I don't know that I've ever actually seen either one. Commercially available (mostly Chinese) VFD's that run off of a 120 V single phase line are normally going to output 208 to 230 V Wye connected 3-phase. Which would more than likely match the motor on the lathe unless it is wound only for 277/440 V 3-phase. How likely it is to be the latter depends mainly upon where it started life (from small machine shop to large factory). You are just going to have to look at it and find out.
 
So I guess the overarching question is whether or not a 1 HP single phase motor at 110V would be an acceptable substitute at least until I can find a way to get access to a 220V 1PH line and then get a VFD for 3PH capabilities. Isnt 1HP at 110V single phase a weaker motor than 1HP at 220V single phase? I can't seem to get a good answer on that no matter who I ask.
 
EA,

As I thought I wrote earlier, 1 HP is 1 HP whether created from 120 V single phase, 240 V single phase, 208 V 3-phase or by a geared gas turbine. That's all assuming that the supply to the motor (or engine) is adequate for the load. The over all efficiency may be marginally better at 240 V but otherwise, they would perform the same.
 
Thanks for all the advice so far, folks. The machine is going to be delivered in two days. I'm thinking for the time being that it'd be best to power the machine with a 1.5 HP 110V single phase motor. Once I move out, I'll get a 220V line and use either a VFD or a rotary phase converter to get the job done. The logic of my concern with the weaker motor is that I don't want this thing to perform like a SB 10K, hence I dont want to power it like a south bend 10K. The side-by-side cuts I made on the Sheldon I ended up buying made the SB feel like a toy.
 
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