The perfect combination of antiquated junk

mbrooke

Batteries Not Included
Location
United States
Occupation
*
A new breaker may trip faster or it may not, there are too many variables to know for sure.
In reality, correct, which then it would not be fair to say that particular FPE breaker is any worse then a new QO.


That being said, I'm certain the FPE is far out of spec given its age and condition, as well as being reset into a fault multiple times.

How can you be certain if you never gave the breaker a chance? Age means nothing. Chances are breaker in a dry conditioned space will be better inside then one only 5 years old with water infiltration.

Thats not to say FPE is stellar, but my point is the breaker may be well within trip curves.
 

romex jockey

Senior Member
Location
Vermont
Doesn't this thread boil down to mag trip levels fellas?

Yes i know there's little in the way for UL standards applicable to miniature OCPD's

And i know we're not a trade who's doctrine demands any field testing here as well

Yet there is a long history of the thermal magnetic qualities of OCPD's manufacturers have been all over since they left the Edison fuse behind

AND there's a world of fundamental theory that goes along with it

So, if you've read so far, ask yourself if this is what an electrician should be up on....

And if you're not inspired, know that our Euro counterparts might just be handing us our azz on this :lol:

~RJ~
 

peter d

Senior Member
Location
New England
In reality, correct, which then it would not be fair to say that particular FPE breaker is any worse then a new QO.





How can you be certain if you never gave the breaker a chance? Age means nothing. Chances are breaker in a dry conditioned space will be better inside then one only 5 years old with water infiltration.

Thats not to say FPE is stellar, but my point is the breaker may be well within trip curves.
Ok, you win on this one. The FPE is fine, nothing wrong with it at all. :roll:
 

mbrooke

Batteries Not Included
Location
United States
Occupation
*
Doesn't this thread boil down to mag trip levels fellas?

Yes i know there's little in the way for UL standards applicable to miniature OCPD's

And i know we're not a trade who's doctrine demands any field testing here as well

Yet there is a long history of the thermal magnetic qualities of OCPD's manufacturers have been all over since they left the Edison fuse behind

AND there's a world of fundamental theory that goes along with it

So, if you've read so far, ask yourself if this is what an electrician should be up on....

And if you're not inspired, know that our Euro counterparts might just be handing us our azz on this :lol:

~RJ~
I will just say this, but mag trips were a UL/CPSC obsession for some time. Of course the root theory has yet to be proven at our 120 volts...
 

mbrooke

Batteries Not Included
Location
United States
Occupation
*
Ok, you win on this one. The FPE is fine, nothing wrong with it at all. :roll:
Well, if that breaker does trip in less then 25 seconds, then I will say that particular breaker has an appropriate time current curve.


But FPE as whole is manufacturing defect after defect coupled with poor engineering. I mean who uses a spring as a fulcrum? I will call the auto makers and tell them they have been doing it wrong all along :lol: :p
 

peter d

Senior Member
Location
New England
Well, if that breaker does trip in less then 25 seconds, then I will say that particular breaker has an appropriate time current curve.
I did not leave the breaker on long enough to find out. Generally speaking, when you hear a loud abnormal hum, that's a good sign that something is wrong and you should shut the breaker off. :p Before we arrived, the homeowner would reset it and it would stay on for some time, much longer than 25 seconds in its faulted condition.
 

mbrooke

Batteries Not Included
Location
United States
Occupation
*
I did not leave the breaker on long enough to find out. Generally speaking, when you hear a loud abnormal hum, that's a good sign that something is wrong and you should shut the breaker off. :p
Wrong, but is it dangerous? Code hints to no.

Before we arrived, the homeowner would reset it and it would stay on for some time, much longer than 25 seconds in its faulted condition.
If true, then yes that breaker is defective and needs to be replaced... along with the while panel.

But, I must ask. How long is the one way lenghth of that circuit from panel to DIY light fixture?
 

peter d

Senior Member
Location
New England
Wrong, but is it dangerous? Code hints to no.
This is where you have to get out of the theory and into the real world. Old crumbling BX "protected" (term used loosely) by FPE breakers is a very dangerous situation, in my professional opinion. Yes, everything works fine until there is a fault. That's when things can get ugly fast.



If true, then yes that breaker is defective and needs to be replaced... along with the while panel.

But, I must ask. How long is the one way lenghth of that circuit from panel to DIY light fixture?
No idea, the routing of the cable was very convoluted through multiple j-boxes, and the cable disappeared into a finished ceiling on the other side of the basement. But couldn't be much longer than 40 to 50' from the panel to light.
 
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