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RPC and electric motor gurus

Ive got a southbend Fourteen lathe. It has the variable speed pulleys that go to a two speed transmission.

It has a 200 volt 3phase baldor motor. Baldor say that it is rated for +- 10% on voltage.

I am using a 5 hp idler with no caps running off of 220

If I try to start the motor in high the motor starter on the lathe chatters before it finally stays engaged. Low speed starts fine.

But the motor gets hot after about 10 minutes of running( you cane keep your hand on it for about 10 seconds before it gets uncomfortable)

any recommendations of what I should do.

Thanks Bill

Reply to
Bill
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Reply to
oldjag

Aside from everything, make sure that your starter (contactor) runs off the utility legs, sounds like it runs off leg3.

i
Reply to
Ignoramus8228

Iggy .... that was it. leg 3 was wired in to the contactor

Reply to
Bill

cool... what are you going to do with 200v issue? Does the motor perhaps have a standard NEMA frame?

i
Reply to
Ignoramus21707

Baldor says its good for +- 10% so that says 180-220v . so I am at the high end. I will run it for awhile and see what it does. It is a standard frame.

Bill

Reply to
Bill

If it is a standard frame, you have freedom to do whatever you want, replacement 3 phase motors are dirt cheap...

i
Reply to
Ignoramus21707

Another question.

will two 5 horse idlers start a 7.5horse?

Reply to
Bill

In my RPC, one 10 HP motor easily starts a 7.5 HP idler (which is not loaded with any mechanical load). I had a test RPC at some point with a 7.5 HP idler, that started a 3 phase 5 HP Atlas Copco compressor.

i
Reply to
Ignoramus7443

I have a "5" hp RPC - it spins up and drives three transformers. The xformers are held off until I want the higher voltage three phase. The peak inrush current is just over 50 amps. Naturally the 50 amp breakers hold up nicely. The transformers drive 6 three phase motors - 3 at the moment - So far so good.

Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder

Ignoramus7443 wrote:

Reply to
Martin H. Eastburn

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