OkiePC
Lifetime Supporting Member
A buddy got a deal on an old lathe and wants to apply power...His shop has 240vac single phase.
I believe this old motor is a 2-speed 3 phase motor designed for 440vac but would like confirmation and advice on what to recommend. For starters, I told him he would do best with a low end VFD that can take single phase input, but I have never tried to put a 2 speed motor on a VFD and I am not sure how to proceed.
When I traced the motor wiring, some of the wires go to what looks like auxiliary contacts on the old contactors, and others seem to go to the main contacts. I didn't take thinks apart too far, but the contactors are different than others I have seen as well.
I think I located two sets of winding with my ohmmeter, but where they are landed had me befuddled. Anyhow if I do determine that there are two separate windings for two speed operation, how do I wire this thing to a VFD (if that is going to work at all)?
Thanks in advance!
I believe this old motor is a 2-speed 3 phase motor designed for 440vac but would like confirmation and advice on what to recommend. For starters, I told him he would do best with a low end VFD that can take single phase input, but I have never tried to put a 2 speed motor on a VFD and I am not sure how to proceed.
When I traced the motor wiring, some of the wires go to what looks like auxiliary contacts on the old contactors, and others seem to go to the main contacts. I didn't take thinks apart too far, but the contactors are different than others I have seen as well.
I think I located two sets of winding with my ohmmeter, but where they are landed had me befuddled. Anyhow if I do determine that there are two separate windings for two speed operation, how do I wire this thing to a VFD (if that is going to work at all)?
Thanks in advance!
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