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Running a 3 phase motors using VFD


Mar 21, 2024
Can all three phase motors including a motor manufactured in the 1950s or 1960s be ran using a VFD ?
When I first purchase my 1956 South bend lathe I connected a VFD to the three phase motor and to the best of my knowledge it was connected properly. The the VFD used was rated at a higher horsepower then the motor I tried using it on. Upon starting the motor it started to produce a light amount of smoke so I immediately disconnected it and connected a digital phase shifter to it and it's been running okay since. I do believe when using a digital phase shifter you are losing 1/3 of the horsepower rating of the motor and I would like to get full horsepower usage from the lathe hopefully someone can give me their input on my situation

Thanks in advance for your help
"All" is maybe too much. I have done LOTS of very old motors with no issues.

I guess some VERY old insulation might not take the VFD. If the motor is worth it a line reactor would smooth the electrical spikes out of the wiring. Many VFDs call for this on long wiring runs.

For the most part, just get another motor.
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