Circuit Breaker derating

[Hameedulla-Ekhlas]

Greeting all

Is there any thing regarding to Circuit breaker derating in NEC code please advise me.

 

[jumper]

Are you asking about 100% for a non continuous load vs 80% for a continuous load.

 

[480sparky]

Greeting all

Is there any thing regarding to Circuit breaker derating in NEC code please advise me.

Never heard of it.

 

[Hameedulla-Ekhlas]

I have already considered the continues and noncontinues load. Today some one asked me regarding to circuit breaker derating. I told him that I have seen cable derating in NEC and I dont have information about circuit breaker derating. So, I searched also in NEC and could not find anything for this.

 

[Lydell]

you can derate the wire, but the breaker MUST be sized according to load and wire ampacity, NEC has the rules for going either up or down as the ampacity allows
.

 

[SG-1]

I have noticed on some of the trip curves for molded case circuit breakers that ambient temperture will effect the opening characteristics of the device.

This may be what you are refering to.

 

[Hameedulla-Ekhlas]

Can you give some more explaination please.

 

[SG-1]

The higher the ambient temperature the less current or time to open during a fault or overload.

I think the standard curves are based on a 30 degree C ambient.

 

[Hameedulla-Ekhlas]

Digsilent power factory Software

Digsilent power factory Software

Does any body have information regarding to Digsilent power factory software. I need some example on that and help files.


Digsilent is a power system analysis software for low and high voltages which is used for power flow and short circuit calculation.