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Have 200 amp service. Installing a subpanel in attached garage. Distance is 35 feet. 17 feet in attic. 60 amp breaker in main box. 100 amp breaker in subpanel(used as disconnect). Running 6-3 romex. Seperate ground and neutral. No ground rod at subpanel. Sound OK? thanks
 

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Looks good to me 6-3 romex - w G should be good up to 80 amps.
 

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Looks good to me 6-3 romex - w G should be good up to 80 amps.
Nope, only good to 55 Amps. Depending on what you are installing in the sub panel, use a 50A breaker.
 

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55 amps by table 310.15(B)(16) in raceway cable or earth
80 amps by table 310.15(B)(17) free air

I think I used the wrong table. I stand corrected, thank you.
 

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Romex is limited to the 60 degree column
 

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Have 200 amp service. Installing a subpanel in attached garage. Distance is 35 feet. 17 feet in attic. 60 amp breaker in main box. 100 amp breaker in subpanel(used as disconnect). Running 6-3 romex. Seperate ground and neutral. No ground rod at subpanel. Sound OK? thanks
In addition to replacing the 60 amp with a 50 amp, this leads to an interesting question. Can a 100 amp breaker be used in the sub as a disco when the feeder breaker (and wire) is not 100 amp?
 

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In addition to replacing the 60 amp with a 50 amp, this leads to an interesting question. Can a 100 amp breaker be used in the sub as a disco when the feeder breaker (and wire) is not 100 amp?
Not a problem, and you can use the 60 amp breaker, because there is not a 55 amp breaker.
 

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Not a problem, and you can use the 60 amp breaker, because there is not a 55 amp breaker.
Thanks for the info, I've always matched the subpanel breaker to the feeder breaker (when they wanted a sub disco.) Do you happen to know the code reference on that one?
 

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Thanks for the info, I've always matched the subpanel breaker to the feeder breaker (when they wanted a sub disco.) Do you happen to know the code reference on that one?
Somewhere in the office, and football is on.:whistling2:


As long as the wire feeding the panel is properly protected, you can have any size breaker in the panel.
 
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