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#27784 - 07/31/03 08:52 PM amperage
ga.sparky56 Offline
Member

Registered: 11/24/02
Posts: 582
Loc: young harris georgia usa
If I feed a 100a main lug panel with say a 40a dp breaker, do I have 40a total capacity? Or do I have 40a available on each leg for 120v loads?

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#27785 - 07/31/03 09:40 PM Re: amperage
amp-man Offline
Member

Registered: 06/23/01
Posts: 144
Loc: Sacto, California US of A
Russell,

Look at it this way--

40A @ 240V = 9600 VA

and

9600 VA/120V = 80A

So, you've got 40A on each of the legs.

Cliff

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#27786 - 07/31/03 09:45 PM Re: amperage
elecbob Offline
Member

Registered: 08/23/02
Posts: 142
Loc: WA
If you touch each of the two little screw heads on the circuit breaker where the wires go with the test leads of a voltmeter and it says 208 or 240, you have 80 amps of 120 volt power available. That's assuming you have a neutral too. Of course.
(signed) Sorry. I forgot my name.

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#27787 - 08/01/03 03:36 AM Re: amperage
ga.sparky56 Offline
Member

Registered: 11/24/02
Posts: 582
Loc: young harris georgia usa
Thank you Cliff and Bob.

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