Circuit Breaker - Branch-Circuit Overcurrent Device - What is the difference?

[Pierre C Belarge]

The new definition in Art 100. What is the real difference between the two definitions?

 

[nakulak]

I'm gonna take a wild guess: one of them may or may not be a circuit breaker ? :grin:

 

[al hildenbrand]

Both are Devices.

Not all OCPD are Circuit Breakers.

Not all Circuit Breakers are OCPD.

 

[SG-1]

Pierre, it seems this definition for Branch-Circuit Overcurrent Device was added in the 2008 Code because the term was used in the definition of Supplementary Overcurrent Protective Device in previous years.

Notice the 5000 Amp fault current interrupting rating qualifier.

 

[Pierre C Belarge]

I read the ROP and could not understand why we need this definition in the NEC. Prior to this code cycle, I cannot remember ever reading of this in the NEC.

 

[SG-1]

I read the ROP and could not understand why we need this definition in the NEC. Prior to this code cycle, I cannot remember ever reading of this in the NEC.

Its needed because it is part of the definition of Supplementary Overcurrent Protective Device.

 

[DARUSA]

In my opinion!!!

In my opinion!!!

A one time fuse in the branch circuit is an overcurrent device but this is not a "circuit breaker".
Also the main circuit breaker in the panel is not the Branch circuit overcurrent device only the breakers in that panel are Branch-circuit overcurrent devices if suppling the branch circuit loads.

 

[Pierre C Belarge]

I just did a search...which I probably should have performed before I wrote this post. This phrase comes up 25 times in the '08 NEC. So much for not paying as much attention as I should have.

 

[Derick]

The new definition in Art 100. What is the real difference between the two definitions?

I think it is one definition split into 3 parts.Upper portion states what it does
and range (Rc and IR).The lower part specifies minimum AIC rating.

Do they even make anything smaller than 5 K?

 

[SG-1]

Do they even make anything smaller than 5 K?

I think it is called a Supplementary Overcurrent Protective Device.