Circuit Breakers Used as Switches

[tandyn]

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

 

[tandyn]

To clarify, is this allowed by NEC?

 

[dpc]

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".

 

[jraef]

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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[itsmoked]

I could also cause some major confusion down the road.

Keith Cress
kcress -

http://www.flaminsystems.com