AFCI - Supplemental vs Combination vs Outlet Branch-Circuit

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mbrooke

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He's Everywhere! He's Everywhere!

Sorry RJ, this isn't a pot shot at you. Chickenman, AKA 'Benton Harbor', was a favorite radio show of mine. Benton Harbor, in case you don't know, is a town in Michigan. Anything Michigan is cool to me.

Plus, Chickenman always saved the day. No matter how screwed up things got.

Iwire is about my age and probably has heard the show. BTW, that means Iwire isn't older than dirt, but may have a few years on most of the sod in the area.

:lol::)

We both understand intermittent nuisance tripping is hard to track on one circuit (trust me, Ive been there for simple short circuits pulling hair) and 24 circuits would be impossible, but if AFCIs were 100% effective at discriminating between dangerous and none dangerous arcing the idea would probably be feasible... and a nice "loop hole" in the code to save money. Why? Because dangerous arcing is extremely rare, if not impossible at 120 volts... ;)
 

mbrooke

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:D

From you, oh the irony of it.


If I feel a poster is misunderstanding the theory being discussed, I will make effort to explain it more in depth.


As far as sub mains, if you don't understand the problem with that for AFCI or GFCIs you are beyond help.


You miss my side of the argument. I understand 40 circuits being looped into the mix vs one being much harder for trouble shooting, but one most ask how common dangerous arc faults truly are... A rare event would actually have the savings look attractive for the one in a million home that needs extensive trouble shooting.
 

K8MHZ

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Michigan. It's a beautiful peninsula, I've looked
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You miss my side of the argument. I understand 40 circuits being looped into the mix vs one being much harder for trouble shooting, but one most ask how common dangerous arc faults truly are... A rare event would actually have the savings look attractive for the one in a million home that needs extensive trouble shooting.

You have to factor in false tripping.

Don't forget that radio transmissions hundreds of feet away can trip AFCI breakers, for example. Besides troubleshooting, a false trip taking out 40 circuits in an instant would really suck.
 

iwire

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H
Iwire is about my age and probably has heard the show.

I don't know the show but I am still feeling kind of old. :)

RJ is known as chicken steve at another forum and if I recall also raises chicken, that is where my chickenman comment came from. mbrooke knows that so I guess he is just trying to stir the pot.

I can cause enough trouble on my own.:cool:
 

mbrooke

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I searched 'Euro AFCI' on Google and came up with nothing.


AFDD would be a better term. At least that is what they call AFCIs in Europe. Its rather ironic, because AFCIs actually originated out of the IEC to some extent...

Just for my own curiosity, what, exactly, is 'the Euro model'?


I will post some pics latter on, but its basically where an RCD (GFP) protects multiple circuits. The idea is that having a sub-main RCD saves money rather then having an RCBO (GFP+thermal mag breaker) on each individual circuit.


https://s-media-cache-ak0.pinimg.com/736x/a5/42/99/a54299b29db578b92ef905f8e78bdb5a.jpg


http://www.crossy.co.uk/wiring/CU-3.jpg


http://www.electronicshub.org/wp-content/uploads/2015/11/Three-phase-wiring-to-home.jpg
 

mbrooke

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You have to factor in false tripping.

Don't forget that radio transmissions hundreds of feet away can trip AFCI breakers, for example. Besides troubleshooting, a false trip taking out 40 circuits in an instant would really suck.


I know, but I did say "100% ability to discern between dangerous and none dangerous arcing"
 

iwire

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a false trip taking out 40 circuits in an instant would really suck.

In a newly built home even with a dedicated subpanel just for the required AFCI circuits a trip would be almost 100% of the lighting and receptacles at the same time.

Not good. :happysad:


It seems to me mbrooke does not understand how difficult it would be to identify an intermittent problem on one circuit when mixed with dozens.

Sure, if the problem is continuous narrowing it down is a piece of cake. It's when the problem is once a week or once every few days etc that it quickly becomes cost prohibitive to stand around and wait.

Is it poorly wired circuit? Is it a bad appliance?
 

mbrooke

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comment came from. mbrooke knows that so I guess he is just trying to stir the pot.

And that might be true, but other members may not know that and think you are making fun of him. RJ has tremendous insight on this subject and I want him to feel welcome being able to share his thoughts in a welcome atmosphere.
 

mbrooke

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In a newly built home even with a dedicated subpanel just for the required AFCI circuits a trip would be almost 100% of the lighting and receptacles at the same time.

Not good. :happysad:


It seems to me mbrooke does not understand how difficult it would be to identify an intermittent problem on one circuit when mixed with dozens.


Sure, if the problem is continuous narrowing it down is a piece of cake. It's when the problem is once a week or once every few days etc that it quickly becomes cost prohibitive to stand around and wait.

Is it poorly wired circuit? Is it a bad appliance?


But my understanding is that all (dangerous) arc faults are continuous rather then intermittent?

https://www.youtube.com/watch?v=uPlELdH0KeM
 

jumper

Senior Member
And that might be true, but other members may not know that and think you are making fun of him. RJ has tremendous insight on this subject and I want him to feel welcome being able to share his thoughts in a welcome atmosphere.

Any member is welcome to share his/her thoughts, within reason, and any other member is welcome to disagree, within reason.

No one gets preferential treatment.
 

GoldDigger

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But my understanding is that all (dangerous) arc faults are continuous rather then intermittent?

https://www.youtube.com/watch?v=uPlELdH0KeM


That is a very good understanding. Now the only issue is whether AFCIs as currently delivered detect only dangerous arc faults. Or even only real arc faults whether dangerous or not.

One complication to the troubleshooting is that an arc fault may continuous and still not re-strike after the breaker has tripped and been enabled again. It may take some other external event to trigger the next "continuous" arc. Continuous by itself does not imply that it will be there immediately after a power cycle.
 

romex jockey

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Vermont
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electrician
Any member is welcome to share his/her thoughts, within reason, and any other member is welcome to disagree, within reason.

No one gets preferential treatment.

Fair enough Jumper.

The Euro model takes a bit of thought for the American spark to process, but it is tried/true. (thx for the links yet again Mr MBrook)

The disconnect we are experiencing here , like most afci threads , is simply lack of theory.

That said, the mighty afci, according to our perennial nema rep, is for fire protection, NOT personnel protection.

So why not address what is considered the incendiary levels of that with afci mains &/or submains?

I'll wager it less a nuisance than that of a 3-5ma trip level , wouldn't you? And as GFP is gone from two manufacturers of afci's , the issue is moot...

I'll also up the ante' wagering there are NRTL's , studies, etc that one could predicate said levels of protection on

Problem is, nobody posting here seems to know what that may be.....

Gee.....:lol:

~R (of fowl fame)J~
 

texie

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Fort Collins, Colorado
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He's Everywhere! He's Everywhere!

Sorry RJ, this isn't a pot shot at you. Chickenman, AKA 'Benton Harbor', was a favorite radio show of mine. Benton Harbor, in case you don't know, is a town in Michigan. Anything Michigan is cool to me.

Plus, Chickenman always saved the day. No matter how screwed up things got.

Iwire is about my age and probably has heard the show. BTW, that means Iwire isn't older than dirt, but may have a few years on most of the sod in the area.

Wow.....Chickenman. Now we are really dating ourselves. I seem to recall this being around the mid sixties? Do you remember the year? I can still hear the Chickenman opening in my head. Are we the only ones that remember this show?
 

peter d

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Location
New England
An AFCI main breaker is the worst idea ever. As for the "Euro model", I could not possibly care less what the Euro model is. I know that one branch circuit dumping an entire panel is unacceptable, both from an installer/contractor standpoint and end user as well.
 

mbrooke

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An AFCI main breaker is the worst idea ever. As for the "Euro model", I could not possibly care less what the Euro model is. I know that one branch circuit dumping an entire panel is unacceptable, both from an installer/contractor standpoint and end user as well.

But thats condemning something without knowing what it is... which is very important in this case because the Euro model was exploited to justify AFCIs...
 
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