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#179203 07/01/08 08:34 AM
Joined: Mar 2003
Posts: 849
250 hp 480 volt three phase
302x125%= 377.5 = 3-500mcm &Gr(per 250.122). 3 inch conduit
Breaker 600A.
125 Hp480 volt 3 phase
156 A
156x125%=195amps = 3-3/0 plus gr. 2 inch conduit
Breaker 250 amp
both either soft starts or VFD.
Wanna check my work guys.
Hair line between Pride & stupidy Right!!!

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Joined: Jan 2001
Posts: 1,044
Tom Offline
Numbers look OK to me.

Can you send me some Pasties? I could send you some Pepperoni rolls in return.


Few things are harder to put up with than the annoyance of a good example.
Joined: Mar 2003
Posts: 849
You mean the ones that go on yer Nipples.

Joined: Jul 2001
Posts: 599
JBD Offline
Originally Posted by Yoopersup
both either soft starts or VFD

80-95% of the time my preference is to use soft starts for starting only applications and to save the VFD's for speed control.

Joined: Jan 2001
Posts: 1,044
Tom Offline

I thought you were a uper, not a loper & I mean the ones you eat.


Few things are harder to put up with than the annoyance of a good example.
Joined: Jan 2004
Posts: 1,507
What kind of breaker?
What environment? Wet? Dry?
What ambient temperature?
What type of insulation on the conductors?
No mention of overloads.
Details, Ernie, details- You know how I am.

George Little

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