In article , SRF says...

I'm setting up a hobby machine shop and am getting into the issue of 3 phase
motors. Most of the motors are going to be in the 1 to 3 horsepower range.
For motors of this size, why would I want to have make three phase power to
run these machines instead of just swapping out the motors for single phase?

Well, I can tell you why I chose to put in a home-made
rotary converter: one of the machines I bought had a
two speed pole changing, three phase motor, and I wanted
to keep that motor in place. For the lathe, I found
that real three phase provides the advantage of plug
(instant) reversing.

And then later, I found I purchased yet another (hardinge)
machine with a similar two speed motor.

The cost of the phase converter itself was miniscule
compared with the cost of changing those three motors,
or installing a VFD for each machine - aside from the
convenience aspects.

Jim

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JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
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