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#27784 - 07/31/03 11:52 PM amperage  
ga.sparky56  Offline
Joined: Nov 2002
Posts: 558
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 - 08/01/03 12:40 AM Re: amperage  
amp-man  Offline
Joined: Jun 2001
Posts: 141
Sacto, California US of A

Look at it this way--

40A @ 240V = 9600 VA


9600 VA/120V = 80A

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


#27786 - 08/01/03 12:45 AM Re: amperage  
elecbob  Offline
Joined: Aug 2002
Posts: 141
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.

#27787 - 08/01/03 06:36 AM Re: amperage  
ga.sparky56  Offline
Joined: Nov 2002
Posts: 558
young harris georgia usa
Thank you Cliff and Bob.

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