What gauge wire for 220 volt, three phase, 7 1/2 HP motor

moxie said:
Hi All,
I recently bought a used 15" LeBlond Regal servo shift. I've spent the last few days cleaning and leveling the machine in my shop and am hoping to wire the machine tomorrow. I think the electrical information plate is stating that it runs at 16.35 amps at 220 volt. I say that "I think" because aside from the stamped in numbers all the painted on data is gone. It will be a wire run of about 45' from the circuit breaker box to the lathe. Do I need 10 gauge or heaver? Will the breaker need to be a 20 amp three phase breaker? Thanks for your advise, Dave View attachment 92896
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From what I see, it looks like 3 phase is required. Do you have 3 phase power available? I would use 10 gauge and a 30 amp breaker although..... Are you sure it is a 7 1/2 HP motor? 18.3 amps seems a little low on 230 volt for that big a motor. My air compressor is 7 1/2 and draws 23 amps at that voltage.
 
compressorguy said:
From what I see, it looks like 3 phase is required. Do you have 3 phase power available? I would use 10 gauge and a 30 amp breaker although..... Are you sure it is a 7 1/2 HP motor? 18.3 amps seems a little low on 230 volt for that big a motor. My air compressor is 7 1/2 and draws 23 amps at that voltage.
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Hi Gary,
I am going by the stamped in info on the data plate. However all the printed on data has been wiped off over time. There is still a data plate on the motor but it is aimed the wrong direction to read it in the cast iron base. I will try getting in there with my cell phone to take a picture of its data plate to confirm the volts and amps.

I do have three phase in my shop. When we bought the warehouse building 16 years ago it was in an industrial zone and when we had the building rewired it was not a problem to bring in three phase. Nowadays the neighborhood has gone upscale residential and we are part of a dwindling group that still build things.

I went to a suburban Home Depot in NJ last night did not find the 30 amp, three phase breaker. I'll have to go to a real electrical supply house here in Brooklyn.

I'm also still sorting out two other issues. One is that the lathe was missing its leveling feet. I tried to level it with shims but picking up a 3300 lb machine and getting the correct amount of shims under 7 pads was hard to do. I learned that the base castings actually have threaded holes for the leveling feet. Thats the good news, but the tough part is that the holes are 1"-16.
Thats not a size I can buy so I will try to make them on my 13" South Bend. I ordered a length of 1" hex material and will try to leave the upper end with the hex and turn round and thread the lower half.

The other issue is that I received a beautiful reversible three jaw Bison chuck with the lathe but with a D-6 back rather then the L-1 mount this lathe uses. The chuck looks great and I don't think it has ever been used. However I'm being told that this particular Bison chuck does not allow for a back change. Something to do with how the company machines this model. (Model 3245-10) I'm going to try and sell it or swap it for a decent brand 10" with an L-1 back.

Dave
10" SouthBend, 13" SouthBend, MSC mill, Van Norman 16, Clausing small knee mill and now 15" x 54" LeBlond.
 
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