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Same Size Breakers in Seires

Same Size Breakers in Seires

Same Size Breakers in Seires

(OP)
Is there any NEC requirement or guidelines relating to breakers of the same ampacity in series?
This would be a situation where electrical system coordination is not necessary.

For example, a 400A main breaker in a panelboard in series with a 400A branch breaker in the same panelboard. Another example would be a feeder requiring a 400A breaker that feeds a 400A panelboard with a 400A main breaker in the panelboard.

RE: Same Size Breakers in Seires

It's not a Code violation and is done all the time.  

RE: Same Size Breakers in Seires

It's actually pretty common when the panelboard or whatever is some distance from the main switchboard and maybe several floors away.   

RE: Same Size Breakers in Seires

You could feed an 800A from a 400A so long as the cable is protected.

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