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PM-30 Power Requirements?

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NuclearSquanch

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#1
Hi all, I have a question regarding the PM-30 power requirements.

The block diagram in the owners manual shows 220VAC with Line, which has a 5A fuse, Neutral, and PE. My question to the forum is does this machine require one hot 220VAC leg, or is this wired with two 120VAC hot legs?

The block diagram is a bit difficult to decipher.

Thanks!
 

jwmelvin

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#2
220VAC, which is the same as two 120VAC legs that are 180deg out of phase. In other words, the "neutral" is not at the same potential as PE; i.e., the machine is supplied by typical 220VAC power in the U.S.
 

pstemari

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#3
Note that if you're feeding in 240 VAC with two 120 VAC phases, you'll want fuses on both legs, not just one leg.

Sent from my Pixel XL using Tapatalk
 

81husky

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#4
I just looked up the wiring diagram, and I see your confusion. I don't know how you get 220 volts with one wire in the USA. I'm curious if there is a L1 and L2 terminal, and it just isn't shown. I'd sent a note or call Precision Mathews, and see what they say.
 

WyoGreen

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#5
I have a PM 30MV, and I'm running it off 240 Volts AC. That diagram is confusing, and I took it as meaning 220v AC across the two legs with no neutral. (which in the U.S. should read 240 v with two 120v legs). At any rate, that is how mine is wired up, and the motor controller has yet to explode or let black smoke out. So unless they have changed the voltage with the latest crop of machines, you should be safe wiring it as 240V.
Steve
 

mcdanlj

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#6
Yes, you run a normal 240V nominal circuit, just like an electric dryer, range, air conditioner... No neutral wire, just ground. Use a single ganged two-leg circuit breaker, not two separate breakers. A lot of equipment tolerates 220V (single leg single phase in most of the world) and 240V (two leg single phase in the US) and often even 208V (any two legs of three phase in the US) without adjustment, and just gets labeled as "220V" nominal. Follow local code, blah blah blah. I used oversize wire as long as i was at it, so that if I get an even bigger mill later I don't have to run wires again, I can just upgrade breaker and receptacle. ☺

The PM-30 ships without a plug, so you can choose your favorite plug style that is appropriate. I used L6-20 for mine.

Note that if you get the power feed and/or DRO they run on 120V nominal, which must be a separate 120V single-leg single-phase circuit; don't run a neutral and piggy-back off one of the two legs in your 240V circuit! If you need to run only one circuit to your mill, you can run an appropriately-sized 240V feed to a small sub-panel by your mill, which will need a separate two-leg breaker for the main mill power, and one-leg breaker(s) for DRO/feed/whatever else you are running off it. Sized and installed to code, do it legal, right, and safe including hiring an electrician as appropriate/required.
 
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