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Phase Perfect - Conversion single phase to 3 phase.

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Threads about addressing conversion from single phase to 3 phase come up frequently. Often one aspect of inquiry is how to make 3 phase machines work with as little spend as possible - people have come up with some great solutions. I got into this hobby 35 years ago, and started out with a commercially made, 5 hp rotary converter. The RPC worked great for that first lathe, and made it easy to power the next 8 machines that followed. In all, I think I have 13, 3 phase motors from very small up to 5 hp. The RPC worked well, the drawbacks were that it did not start the lathe well on the higher speed motor setting. With the 4J chuck on I'd get one start and the second start befor too long would trip the RPC thermals. Also, the particular unit was quite noisy (though I have seen others that are much quiter).

I've wanted to play with a CNC machine and when an agreeable opportunity for an industrial machine came up, I took the plunge. This VMC has a 15 hp spindle motor and most of the advise I got was that it was a poor idea to run this unit on an RPC. The best solution would be a Phase Perfect. So off to the store for a 20hp PP. The price tag was painful, it cost as much as the VMC!

Phase Perfect is a solid state phase converter, similar to an RPC in that L1 & L2 pass right through, the voltage balance is essentially spot on and it is rated for motor starting right to the capacity of the machine (20 hp) in my case. Needless to say the 5hp motors start very well (sort of like having 8 new speeds on my lathe to choose from). There is an annoying buzz, which I can't hear as soon as a machine is running.

As a whole shop solution it is awesome. I had to pull a new supply for the converter (it is a higher current device), but for the rest I simply swapped the supply to the 3 phase sub-panel and everything was available to run. The VMC started great (I know nothing about CNC stuff - however that will be another post). I encourage more folks to consider PhasePerfect - and this coming from a person who is a fan of RPC phase converters (and a penny pincher too). I've no affiliation, just a satisfied customer.
 
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I bought the 10HP version 12 years ago. Starts the 10hp motor on my lathe with no complaints but it has a clutch so spins up easy.
That annoying high pitch buzz goes away with age, getting deaf so it doesn't bother me anymore. That lends to my only complaint about the unit, they need a bright indicator light, been meaning to hook up a 60 watt bulb for an indicator, it occasionally gets left on overnight as it sits there pretty much silent.
The big lathe will work it enough to turn on its internal cooling fans, but the Hardinge and the surface grinder won't make them come on unless the shop is really hot in the summer.

Greg
 
F350ca,
I am so glad to hear you say that.
I called American Rotary Thursday, just about had me talked into a 15 hp ADX15 RPC to Run my Clausing Colchester 15.
Meanwhile I had some discussions with some friends in this forum that feel the 15 is overkill for my 7.5hp motor.
The Clausing is clutched, full speed until the spindle is engaged.
I bought the American Rotary ADX10. Saved $600. Hope it is ok.
I feel pretty good about it.
 
Having a clutch certainly reduces the inrush current. I've had no experience with rotary phase converters but would guess you'll be alright, the Phase Perfect is designed to start a 10HP motor under load, the clutch just makes it easy.
The Summit lathe I have uses a wet clutch / brake pack. With a heavy part in the 16 inch four jaw it takes it a couple seconds to spin it up.

Greg
 
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