Is a main breaker ever required on a subpanel?


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Old 12-08-19, 02:23 PM
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Is a main breaker ever required on a subpanel?

This job at my home will have a sub at a detached building and has more than 6 handles.
 
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Old 12-08-19, 02:59 PM
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If the subpanel is in a detached structure and has more than 6 breakers a main disconnect is needed. If the subpanel is in same structure as the main panel then a main breaker is not needed in the subpanel.
 
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Old 12-08-19, 03:52 PM
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A detached building does need to have a disconnect somewhere. The panel does not need to have a main breaker. There could be a separate disconnect on the feeder to the sub panel.
 
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Old 12-08-19, 04:26 PM
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A detached building does need to have a disconnect somewhere. The panel does not need to have a main breaker. There could be a separate disconnect on the feeder to the sub panel.
I have no clue what is required in Canada, but what you are saying is not clear as to the NEC in the US. If the detached structure has a subpanel with 6 or less breakers to cut power to all circuits then a single disconnect at the detached structure to cut all power at the detached structure is not needed. The 6 or less breakers are the disconnect. The feeding breaker in the main panel back at the supplying structure does not count as the disconnect for the detached structure.
 
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Old 12-08-19, 05:31 PM
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Joe is saying the means of disconnect does not need to be a main breaker in the panel. It can be a disconnect ahead of the panel at the outbuilding.
 
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Old 12-08-19, 05:56 PM
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OK. What i think i read is that 6 handles or less is fine as is. More than that requires a single main, in the box or ahead of the sub somewhere on or in the outbuilding.
 
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Old 12-09-19, 05:05 AM
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Telecom, you are correct.
 
 

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