Trip curve for FPE NEF421050 breaker?
Trip curve for FPE NEF421050 breaker?
(OP)
Good afternoon.
I have been asked to compile information for an arc-flash survey. One specific request is giving me some trouble. I need to find a trip curve for a 50A federal pioneer electric breaker, cat #NEF421050. This is on a 129vdc system. I am aware of the history of FPE breakers and understand that these trip curves may or may not be relevant for real life applications, but we still require the data to run the calculations.
Any information would be greatly appreciated.
Thank you very much.
I have been asked to compile information for an arc-flash survey. One specific request is giving me some trouble. I need to find a trip curve for a 50A federal pioneer electric breaker, cat #NEF421050. This is on a 129vdc system. I am aware of the history of FPE breakers and understand that these trip curves may or may not be relevant for real life applications, but we still require the data to run the calculations.
Any information would be greatly appreciated.
Thank you very much.






RE: Trip curve for FPE NEF421050 breaker?
I have nothing in my files about that FPE breaker. Try a website Widespread Electrical Sales, they have your breaker in question. Enter the part # and some of the spec's are shown. A note below request for a "cut sheet" that might be the trip curves.
I don't like FPE breakers period. I saw a 34 year old electrician loose his right hand and his face burned badly. All he did was turn off a 60 amp MCCB, with no load on it. The cause was never indentifiled. FPE tried like hell to say it was his fault in court. I was on the witness stand just before noon recess. During the recess I was paged by my office. There was 2 other same breakers exploded the week before. FPE still said it was his fault, the jury rewarded him $7.2 million plus all his employer Workman's Comp for all past and future Medical bills. That was in 1984.
The 129vdc sounds battery voltage for swgr. The MCCB is rated 14kA @ 480v I do not know if is rated the DC, bet it isn't.
Good luck.
RE: Trip curve for FPE NEF421050 breaker?
RE: Trip curve for FPE NEF421050 breaker?
RE: Trip curve for FPE NEF421050 breaker?
Melspuds, I understand and completely agree. Thank you for the insight.
RE: Trip curve for FPE NEF421050 breaker?
Anyways, here is the curve. This is for Federal Pacific NEF, I didn't know Federal pioneer had a NEF?
RE: Trip curve for FPE NEF421050 breaker?
Thank you very much everyone!