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Circuit Breakers Used as Switches

Circuit Breakers Used as Switches

Circuit Breakers Used as Switches

(OP)
Can a larger circuit breaker be used as a switch on a fused circuit sized for a lower current?

i.e. a 70A breaker used as a switch on a circuit fused and sized for 40A

RE: Circuit Breakers Used as Switches

(OP)
To clarify, is this allowed by NEC?

RE: Circuit Breakers Used as Switches

Yes, as long as the circuit conductors are protected by the upstream fuse, I believe this would be allowed.  

I await enlightenment from one our "code lawyers".  

RE: Circuit Breakers Used as Switches

Assuming you are in North America...

A Molded Case Circuit Breaker (MCCB) would need to be labeled "SWD" for  switching duty I believe, but as far as I know, almost all new MCCBs are now labeled as such. But the term "circuit breaker" is a little nebulous now with the advent of what are called "Mini Circuit Breakers" or MCB from IEC countries. I do not believe they are going to be labeled to be used as switches.


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RE: Circuit Breakers Used as Switches

I could also cause some major confusion down the road.

Keith Cress
kcress - http://www.flaminsystems.com

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