'Proof' that AFCI devices really locate arcs.

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Tony S

Senior Member
A little interjection gentlemen, I find this thread frightening.

It’s on the cards for the UK to introduce AFCI’s or AFDD’s as they’re already designated for the EU. They’re coming in by stealth methods not by open discussion.

The more I read the more I learn and now I’m well and truly set against them.

As I said, sorry for the interjection but the more information I get the better the argument.
 

mbrooke

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Technician
A little interjection gentlemen, I find this thread frightening.

It’s on the cards for the UK to introduce AFCI’s or AFDD’s as they’re already designated for the EU. They’re coming in by stealth methods not by open discussion.

The more I read the more I learn and now I’m well and truly set against them.

As I said, sorry for the interjection but the more information I get the better the argument.



Its absolutely wrong and the UK should not take them. The very lab testing done on arcing actually proves Earth fault loop Impedance with disconnect times mitigates them. The majority of UL1699 is passed by GFP, which the UK already uses on most circuits. And your fused plugs take care of cords.


Let me be the one to say the UK has already had AFCI protection for the last 30 years, if not more.

And series arcs are a total shill. The above report on glowing connections disproves the 5 amp threshold.

AFCIs only took ground here from hyped fire statistics that have yet to be proved as the result of arcing.
 

donaldelectrician

Senior Member
A little interjection gentlemen, I find this thread frightening.

It’s on the cards for the UK to introduce AFCI’s or AFDD’s as they’re already designated for the EU. They’re coming in by stealth methods not by open discussion.

The more I read the more I learn and now I’m well and truly set against them.

As I said, sorry for the interjection but the more information I get the better the argument.





Maybe we should start an INTERNATIONAL Movement against the evil AFCI .





Don
 

mivey

Senior Member
Ok that might require an more advanced block that can take 4 hots. But for typical circuits this can perhaps explain it better:
Explains what? Whether it be wirenut, Wago, Polaris, etc. they have a means to hold the conductors and to insulate and in some cases provide connection between conductors. Breaking it down you have a small amount of insulating material (plastic, porcelain, rubber, etc) and something to provide structural integrity and/or compression. For a porcelain wirenut, the insulation and mechanical strength comes from the same material. For some a small spring provides the holding strength. You can have a plastic cover, rubber boot, etc.

For the wirenuts you pictured, there is a very small amount of plastic and a small wire spring...probably less material than in the connector shown next to them (especially if you were to use the appropriate 74s). The wires occupy the void space.

Slice it anyway you want with wirenuts, Wagos, etc. and you only occupy more real estate when you add the thermal switching mechanism. Having to bring in additional conductors also takes more time. Even if you wish very very very hard that it isn't so, and try your very very very best to imagine it is not a more complex and time-consuming connector, that is just the way it is.
 

iwire

Moderator
Staff member
Location
Massachusetts
Even if you wish very very very hard that it isn't so, and try your very very very best to imagine it is not a more complex and time-consuming connector, that is just the way it is.

What if puts on his ruby slippers and clicks his heals together three times? :D
 

mivey

Senior Member
I'm pretty sure we have no right or ability to bind someone's words like that.
Not binding anybody, just responding to your making excuses for him. If a poster is learning, then going out in left field might be expected. If the poster says something that doesn't make sense and posts it as if they speak from experience, then expect to be questioned. You tried to excuse that by saying he has a power systems background and not so much experience as an every day electrician.

I know you agree with what he has to say about AFCIs but you are questioning my questioning. Don't worry, what he says about the thermal switch connection is not tainting what he says about the AFCIs, at least as far as I'm concerned anyway.

Man, I must really be bored to talk about this. I think I'll drop out and get some supper.
 

mivey

Senior Member
What if puts on his ruby slippers and clicks his heals together three times? :D
[eyes closed, heels a-clickin'] "there's no place like France for a glowing connection solution...there's no place like France for a glowing connection solution..." :D
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
Explains what? Whether it be wirenut, Wago, Polaris, etc. they have a means to hold the conductors and to insulate and in some cases provide connection between conductors. Breaking it down you have a small amount of insulating material (plastic, porcelain, rubber, etc) and something to provide structural integrity and/or compression. For a porcelain wirenut, the insulation and mechanical strength comes from the same material. For some a small spring provides the holding strength. You can have a plastic cover, rubber boot, etc.

For the wirenuts you pictured, there is a very small amount of plastic and a small wire spring...probably less material than in the connector shown next to them (especially if you were to use the appropriate 74s). The wires occupy the void space.

Slice it anyway you want with wirenuts, Wagos, etc. and you only occupy more real estate when you add the thermal switching mechanism. Having to bring in additional conductors also takes more time. Even if you wish very very very hard that it isn't so, and try your very very very best to imagine it is not a more complex and time-consuming connector, that is just the way it is.


Look at the size, its equal to 3 wire nuts. And who said that device cant hold, splice and insulate a conductor? :blink: Your making random assumptions.

And again, in a 3 wire to 3 wire splice what extra conductors? Actually in most cases what extra conductors?

Im not wishing anything, I just think you refuse to see something.
 

mbrooke

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Location
United States
Occupation
Technician
[eyes closed, heels a-clickin'] "there's no place like France for a glowing connection solution...there's no place like France for a glowing connection solution..." :D

Why do I get the odd feeling something about France is the issue? :blink:
 

romex jockey

Senior Member
Location
Vermont
Occupation
electrician
et tu brutus?

et tu brutus?

Ul doc>>>Technology for detecting and monitoring conditions that could cause wiring system fires


Capture_zpsniubsa1w.jpg


UL test records

arc%20simulator_zpsybdjtqy4.jpg


~RJ~
 

mivey

Senior Member
Look at the size, its equal to 3 wire nuts.
You are not understanding. Think about it logically and hopefully you will see your error. Perhaps you think the air in the skirt matters? A Wago has no skirt like that. Neither do some wirenuts. Come on, think about it. It is about as compact as you can get.

And who said that device can't hold, splice and insulate a conductor?
No one that I've heard. Where do you get that?

:blink: Your making random assumptions.
I'm not assuming. I'm using common sense and experience. Try it. Think logically and not with enthusiasm about the switch.

And again, in a 3 wire to 3 wire splice what extra conductors?
None. But you might be surprised that there are other type splices. Many others.

Actually in most cases what extra conductors?
Most cases? That your every day electrician experience speaking again?

I'm not wishing anything, I just think you refuse to see something.
Let me see if I can simplify it for you. In simple terms, a common simple wirenut, Wago, etc. has a small layer of metal wrapped on top of a bundle of conductors. This could be a small piece of metal joining the conductors in the case of a Wago. The point is it is a very small piece of metal. We also have a thin layer of insulating material. These are combined in a package that is about as compact as you can get. Not much room for anything else.

This is about as efficient as you can get: a metal wrap with a plastic coating. Tightly packed.

Add a fusing & switching & bypass mechanism to this plus space for additional conductors and it will only get bigger. Common sense. No two ways about it.
 

user 100

Senior Member
Location
texas
Fail resistant crimp/solder connections

I don't know about this one. I'm old school but I'm not that old school. Reintroducing soldering/crimping to residential would present all sorts of problems as most people who wire houses today have no idea how to apply either safely to solid conductors> Most of the old solder kings have passed on.Most young ropers have no idea what a c24 is, (though it is still used and even required for crimping egcs in some locales) let alone how to use it correctly and the youngest of the men who lugged that tool and used it regularly to squeeze copper barrels around twisted solid cccs in the '50s and '60s are now collecting medicare. Many guys wouldn't even bother to purchase this tool anyway due to $$ and would end up using the crimp punch on their linemans-causing a bad connection.There is also no guarantee that either one these methods would done correctly-I remember hearing that one of the problems with the crimp method was that some guys squeezed the c24 too hard and would almost cut the wires in half-this method of tying togther cccs is NOT friendly to the unfamiliar and neither is soldering.

Next comes the issue of insulating those joints: Most ropers today have come up during a time when applying tape insulation to a joint isn't as common as it once was and as a result don't know how to tape a crimp/solder joint correctly or apply heat shrink-this is a huge reason why a return to these methods would worry me. They do sell caps for the crimps, but invariably many ecs will embrace scotch 700 or less ($$$).

Imo, while these are both good sound methods and they are still listed, much like shallow sectional boxes and the bracebits used before routing k&t, they also have their place in their rearview mirror or a museum when it comes to new residential-Be thankful for modern products.

Wirenuts have been used regularly for over 4 decades and are cheap, idiot proof(most of the time), easy to inspect/remove, and reliable when installed correctly.
 

peter d

Senior Member
Location
New England
Not binding anybody, just responding to your making excuses for him. If a poster is learning, then going out in left field might be expected. If the poster says something that doesn't make sense and posts it as if they speak from experience, then expect to be questioned. You tried to excuse that by saying he has a power systems background and not so much experience as an every day electrician.

I've said from the beginning that the thermal fusing idea is a bad one, even before reading all the details about it. I agree with you that the idea itself shows a distinct lack of hands-on field experience because it is so impractical. So I guess I don't know what else to say other than that you're right.


I know you agree with what he has to say about AFCIs but you are questioning my questioning. Don't worry, what he says about the thermal switch connection is not tainting what he says about the AFCIs, at least as far as I'm concerned anyway.

Man, I must really be bored to talk about this. I think I'll drop out and get some supper.

Me too. :p
 

peter d

Senior Member
Location
New England
But our installation methods need to change. No need to pre-twist needs to be be removed from the instructions. In truth unless you make the connection up with your tools and visually have conformation of your splice a wire nut guarantees nothing. It is possible to push one of the conductors down further with the skirt hiding it, making poor contact that can lead to a glowing connection down the road. Also possible is having the spring act as a conductor, something its not.

Nothing in our installation methods need to change. I can make a perfectly good splice without pre-twitsing and so can any other electrician. I'm not intending to start a pre-twisting debate but you're really reaching with your commentary here. There are literally countless billions of wire nut splices operating without a problem because they were installed correctly in the first place. If your goal here is to replace wire nuts with this gimmicky thermal fuse/ground fault type of device, then I must vigorously and publicly oppose that.




Back stabbed outlets are another gripe. Those need to be outlawed. The failure rate is astronomical compared to side wired and back clamped varieties. The failures are driving up fire statistics.

Here we agree 100%. A simple change outlawing them would be far more effective and useful than any AFCI.
 

mbrooke

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Location
United States
Occupation
Technician
Again, Vour kind comments are appreciated. The following is another one of my long winded posts but never the less there may some merit.

Thanks! Ha vent forgotten about this post, was busy. And, I disagree, you post does have merit. I like your input :)




My concern about arc faults is that term is not specific enough, a bit ambiguous.at best.
So often an arc will not draw enough current to approach the magnetic trip pickup of a TM breaker.

I agree. Even hard short circuits sometimes don't trip breakers magnetically, especially older breakers that often have a 32x magnetic trip. FPE, Bulldog and some Zinsco breakers do not have any magnetic trip fwiw.


And I am also to understand that the current goes down as the impedance of the arc increases the longer it persists. Am I correct? Arcs are not a good thing as they are unpredictable often not conducting enough current to trip a TM breaker. And to draw enough current trip a breaker thermaly would be would not be reasonable.

You are 100% correct. Much of it is the fact an arc or sputtering fault does not draw a sinusoidal current. Current will rise and fall, and arcing will often re-strike at the peaks and troughs (draw current) but extinguish when rising from or falling toward the zero crossing in a sine wave. This results in a high peak current, but low RMS current. The bimetal strip in a breaker relies entirely on I2R RMS heating, so in such a condition the bimetal can take a very long time to heat up enough to trip. In some cases the bi metal may even see the current as a mild overload or even normal load. Incident energy at the fault increases astronomically. Magnetic trip on the other hand does not rely on RMS heating, so tripping is without delay.


The only place in the NEC that I can think of that time tyo address faults is art 430 with mag only breakers as a part of a combo starter.
The OLR element/adjustment is a thermal element that protects the motor from an overload condition. The mag only breaker is described to provide ground fault protection interesting enough ref art 430-52. Mag only breakers in this application are referred to as MCPs, motor "circuit" protects who's job is to protect the motor circuit. MCPs were originally invented by Westinghouse to deduct the incidence of fires as a result of a failing motor which the commonly used fuse did a very poor job of preventing. Knowing that the LRA of the common motor is about 7x the FLA and that the inrush magnetizing current may be as much a 13x the FLA if we adjust the mag pickup just outside of those currents as to not cause nuisance tripping we can get close enough to a point where should one one the motor winding fasil and go to ground the fault can be sensed by the MCP and trip preventing the arc from escalating into a phase to phase fauld an a catastrophic failure.


Perfect real world example. The same concept if applied to branch circuits will do the same as a branch/feeder AFCI. A study should be undertaken to factor in what is the greatest inrush of appliances and electronics that are plugged into general use circuits.


I would !like to see this concept used in branch circuit protection but it is of my opinion that it would be difficult at best unless the mag mag calibration be reviewed.

I agree, but determining what minimum magnetic trip level is suitable will be easier, by far, then the AFCIs studies undertaken. In fact one poster claims that one company alone already invested at least $10,000,000 in AFCI development. Certainly that can pay for magnetic trip research several times over:

http://forums.mikeholt.com/showthread.php?t=166586&page=12&p=1623075#post1623075

I can tell you this, the cost of development and continued development of AFCI's by only one company ( I wont mention) is well over 8 figures. Thats at the least $10,000,000.00 on a single product. Thats testing, development and so on.




What it boils down to is load center breaker have to be made very , very cheaply. As such it has been my experience with the product that I supported that they are made in groups such as 15, 20, and 30at have the same mag pickup because it would be cost prohibited to calibrate them separately.

The cost to add a solenoid coil to each 15 and 20amp breaker would increase the cost by a dollar or two, certainly cheaper then AFCIs. Breakers used outside of the US and Canada are all equiped with a solenoid coil that lowers the magnetic trip to about 5 times the handle rating. Type C and D are avalible for inrush applications, but type B (5x) is used on nearlly all general use circuits.



The only manufacturer that I'm aware of that has reduced the mag calibration of their standard breaker is SqD while providing an optional highmag, the highmag I found to be the same as the C-H standard breaker, C-H offering an optional lowmag similar to SqDs std breaker which is something your mother never taught you I bet.
I do think that tasking a good look at the mag calibration of the 3/4 and 1" per pole breakers should be evaluated.

I agree, this concept should be reviewed and applied to all breakers. Take a look at what everyone else does :eek::

https://www.google.com/search?q=dis...vEf0o8tI3zF9t&q=disjoncter solenoide &imgrc=_
 

mbrooke

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Location
United States
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Technician
Nothing in our installation methods need to change. I can make a perfectly good splice without pre-twitsing and so can any other electrician. I'm not intending to start a pre-twisting debate but you're really reaching with your commentary here. There are literally countless billions of wire nut splices operating without a problem because they were installed correctly in the first place. If your goal here is to replace wire nuts with this gimmicky thermal fuse/ground fault type of device, then I must vigorously and publicly oppose that.






Here we agree 100%. A simple change outlawing them would be far more effective and useful than any AFCI.

When a wire nut is put on without pre-twisting the issue arises that one of the conductors can be pushed down further then the others with the skirt hiding it. I pre-twist all my splices and then cap them. In most parts of the world terminal blocks and lever wagos are used to reduce the likely hood of this.


If you guys find a temperature sensing wire nut bad, wait until you see what solution AFCI makers have for that :eek: Then you will see what impractical looks like :jawdrop:
 
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