Is a circuit breaker rated per pole or total?

Issue:
Is a circuit breaker rated per pole or total?

Product Line:
Circuit Breakers

Resolution:
Each pole is rated for the specified amps. The poles are not additive, so there is no relavant "total amperage" that the breaker is rated for. Each pole is protected individually, and if any pole exceeds the rated amperage, the breaker will trip. If all poles are below the rated amperage, regardless of what the pole amperages add up to, then the breaker will hold. For example, if a 3 pole, 600 A breaker has 800 A on one pole, and no amperage on the other two poles, it will trip. If it has 500 A on all three poles, even though that "total" seems like it would add up to 1500 A, more than the 800 A in the first example, the breaker will hold, because no individual pole is above the rated 600 A.

The same thing is true for the breaker's interrupt rating. If none of the breaker poles experience more than the rated interrupt capacity, the breaker will be able to trip and be put back into service, and the "total" amperage across all 3 poles during the fault event isn't relavant.

Released for:Schneider Electric USA