Calculating load of sub panel


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Old 09-19-17, 05:41 PM
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Calculating load of sub panel

I have a 200amp service panel outside for my main home.

i just bought and placed a 12x24 shed that's been converted for living quarters.
My plan was to run a 100amp service panel from my 200amp main panel. I will most likely need the whole 100amps for the shed BUT I just looked in my main 200amp panel and it already has breakers in use that total 165 amps. So if 165 amps is already being pulled from this 200amp panel then that only leaves me 35 amps that's free to use for a sub panel right??

I don't know electrical at all but am I right in my assumption?

Cause again I planned to put a 100amp breaker in the main panel to feed the sub panel.
 

Last edited by Cheeva316; 09-19-17 at 07:04 PM. Reason: Solved
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Old 09-19-17, 05:48 PM
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You don't add up the breakers. You need to calculate what the possible peak loads are at one time.

Edit: I just added up the breakers in my 200A panel and the total is 665 amps. No joke, 665.
 

Last edited by pattenp; 09-19-17 at 06:08 PM.
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Old 09-19-17, 05:57 PM
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Old 09-19-17, 06:18 PM
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Ok lol thought I was in for a mess. Thank you very much.
 
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Old 09-19-17, 08:23 PM
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pattenp I just added up the breakers in my 200A panel and the total is 665 amps. No joke, 665.

Mine, including two sub-panels, is more than 900. I win!
 
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Old 09-20-17, 06:43 AM
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Mine, including two sub-panels, is more than 900. I win!

If you are counting the breakers in the subpanels along with the subpanel feeding breakers in the main then that is cheating. I have two subpanels off my main panel and if I include those breakers I have 1010. You lose.
 
 

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