Phase conversion for C&P Cylinder press

I’m considering a C&P Cylinder press for my residential garage shop. The motor is 3HP, 3-phase. What would be my best option for converting the power?

Thanks! Kevin.

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the question is if you want to operate the motor in 3 phase 220v or 380v that is usually done within the same motor wiring as a y or a 3 in in line usually there is a drawing on the motor now if you wanto to run it on single phase you will need a capacitor in this case you will lose hp but 3hp seems like alot anyway


I was considering the same question up until very recently, probably for the exact same press.

The best thing to do is to scoop up a Variable Frequency Drive (VFD):

For a 3HP motor, you’ll need a 240 volt circuit to feed the VFD.

kevin, Good Buddy, here in U.K. we comprehend (Note comprehend not fully understanding) that generally in the States, you have 2 *hot Legs* @ 110 volts per leg, which apparently makes it easier than here to reproduce artificial 3 phase, i.e you only have to pesumably, make one phase *LAG* by 120 degrees, equating to 3 power pulses per 360 degrees, @ 60 cycles per second, whereas here U.K. we have to create 2 artificail phases from our single phase at 240 volts at 50 cycles per second.!!
Although we now have very sophisticated artificial 3 phase units, they come at a price, we still have many older Converters/inverters working well, mine included, I run a lathe with 2 speed, 3 phase motor, @ 3 H.P. from an older unit, switchable for 1 1/2, H.P. >>4, H.P, and 8 H.P. it will run, (if I could) around the clock on the 4 H.P. position, with no trouble, seems to burn less electricity than a 4 H.P. machine running on single phase, we understand that the older units, produce only comparativeky crude artificial 3 phase, i.e. plus or minus 2 or 3 degree pulses either side of the 120 degree mark, makes no apparent difference to the lathe, with one tiny exception, for fun I put a mechanical rev. counter on the lathe, and just at *Half Time* on Cup Final day, which I would not watch anyway, when half the country *Puts The Kettle on* a volt drop on the single phase supply just slows the lathe down a minute fraction.???
Our far more modern Hi-Tech units produce virtually perfect artificial 3 phase, hopefully Stateside you are, up to speed, mine comes into the *Ancient* variety but is not so difficult to replace the Big transformers and Capacitors, if/when, but not YET.?
Apologies if this be irrelevant rubbish, but may give clues to alternatives, perhaps even staying with the original motor.??

One more little problem from way back, (but now solved with Hi-Tech software) my favourite *Toy* is The/My “Seeburg” Juke box, loaded End To End with Rock and Roll,! of course, ex Seeburg out of Chicago, where else, The original problem is/was when they arrived here they were working of off, one leg @ 110 volts but at 60 cycles per second, ours are 50 cycles per sec.we could step the voltage UP to 220/230 our norm, but the frequency turned the 45 R.P.M. records slightly wrong, so the problem was solved by cutting a small gear to turn the disc at the correct speed, Elvis Presley, Buddy Holly,, Johnny Cash, Carl Perkins, and Many Many Many more, HAVE TO BE just right, for example, Elvis on the Juke box, has to be able to be In Sync, with an *Eight Track Tape* of the same piece, I do and I have. Thats eccentric or passionate, take your pick. Good Luck with your power supply. Mick.

al that high tech stuff you are talking about is more expensive than a new motor. i dont see the point in investing that much in a probably 60 to 80 year old motor if you want variable speed you can atach a 3 channel pulley, really not necessary but….

IF you can find a motor with same speed, dimensions and mounts, then by all means replace it: not easy on most cylinder presses, with very specific size and mounting requirements. Speed variations are almost always in power train not motor.
I’ve used rotary phase converters on two cylinders and one offset press, and the biggest problem is they are very noisy. But they are more efficient than VFD methods, so perhaps better in the long run for a busy shop.

A three phase motor will provide more starting torque and has less to break down (no starting windings or switches to fail. Depending on the HP requirements and if there is a separate motor for the air vacuum/blower, a VFD may fit the bill, but a rotary will probably be cheaper and more efficient.

Much of the equation will depend on how the press speed is controlled (mechanical, electrical step control etc.) One thing to consider is that many cylinders will behave/feed/deliver differently at different speeds—changing speeds in mid run may not be the best idea. However, the soft start capabilities of modern VFD’s can make your life (and your power supply requirements) much nicer.