Circiut breaker terminology
Circiut breaker terminology
(OP)
We received a technical spec from Japan (in English) with reference to circuit breakers types ELB (earth leakage breaker) and NFB (non-fused breaker). Could anybody advise if these types have a corresponding designations in the USA? Or any reference to get educated about these types of breakers?






RE: Circiut breaker terminology
In the USA all breakers are assumed to be non fused, unless it is specifially stated to be fused. So yes there are fused circuit breakers available. There no accepted abbreviations or acronyms for that that I know of.
There are two types of fused circuit breakers, ones that have Class L fuses only to provide back up short circuit protection and to have a higher short circuit current rating (SCCR or AIC) as a combination of the fuse and the breaker. Other type of fused breaker have current limiting fuses to make the assembly current limiting type and also have higher short circuit rating.
RE: Circiut breaker terminology
http:/www.jraef.com
Eng-Tips: Help for your job, not for your homework Read FAQ731-376
RE: Circiut breaker terminology
All breakers are not "assumed" to be non-fused, but they generally are. The key, as your Japanese engineer did, is to specifically state in your specifications if you really do not want fused circuit breakers. Otherwise, a vendor will propose fused circuit breakers (to meet the short circuit ratings if needed). The fused circuit breakers have their own issues, such as cost, physical size and coordination challanges.
Visit website of GE, SQD, Cutler Hammer etc for more info.
RE: Circiut breaker terminology