AFCI Breakers

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romex jockey

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electrician
One can try this themselves >

https://www.youtube.com/watch?v=iLmC5quELrE

MH has published this nfpa EE here btw. , This is no secret either.....

This is a real world scenario, not some lab setup construing parameters that do not exist in the real world.

But you'll never see this mentioned in some trade rag OpEd, nor will you read of Joe Engel (a Phd EE should rate), or Paschens law

And that's just us, the so called "pros"

<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

There is little in the way of "public knowledge" about AFCI technology , other than what it's manufacturing cheerleaders forward to them.

This is because they TRUST us

If in fact they were truthfully advertised , acknowledging that they do what they say they do, at 15KV, methinks their sales would not be what they are.

Sadly for now it's empty fire extinguishers ......

~RJ~
 

bphgravity

Senior Member
Location
Florida
It's bizarre how some of you jump to conclusions and shoot right from the hip without a complete understanding of your target. You claim there are no series tests and yet most of you have never even read or researched the standard. You then find out there is indeed series tests, two in fact, and then you shift your focus onto the cable specimen conditioning process and plant your distrust flag there. But again, you have missed the mark.

The point contact arcing test simulates the instantaneous-type arcing which occurs at 120V but at much higher fault currents (75A-500A) as a result of the simulated ground-fault. The carbonized arc tests are a real-world simulation for damaged, aging, misused, and other stress-related conditions over time. At 120V and as little as 200mA, even minor damage to a conductor may result in arcing which could break down the insulation and potentially create carbon buildup around the conductors. This is called the "build-up" or "conditioning" stage. As voltage is applied to the high resistance but conductive path, the carbon burns away resulting in more arcing and more carbonized deposits. Combustible gases are also created by this process. This repetitive cycle ultimately sustains itself to a point where the chain reaction produces enough energy to ignite the combustible gases and surrounding combustible materials.

So, how do you reproduce this real-world event in the laboratory? The solution derived after literally thousands of hours of research and testing is the "conditioning" process outlined in the standard today; carbonized fault simulators. The fault simulators reproduce, in a very short period of time, exactly what occurs on real-world branch circuits in weeks, months and years. A good analogy would be water frozen into ice. You can freeze water slowly or you can freeze water quickly. Both methods produce ice.

The AFCI is not tested on the conditioning voltages, but at rated voltage (120V). The AFCI can't and doesn't know if the hazardous arcing is a result of simulated or natural conditioning.

The "test" performed in the video linked above is absurd and most certainly doesn't simulate a "real-world" condition that could result in fire. In fact, it more closely resembles non-hazardous arcing that occurs in normally operating appliances, motors and switches which would result in unwanted tripping of the AFCI device. The gentlemen conducting the test apparently hasn't read the standard either nor understands the physics of hazardous arcing.
 

romex jockey

Senior Member
Location
Vermont
Occupation
electrician
Now that we've established your offerings as hubris , allow me to unfuzz you Bryan

Manufacturers , not UL create standards .

The NEMA afci task force was split into two camps, those that wished for 'real world' testing (as Bob H demonstrates), and those that wished for arc simulators .

That later won out, hanging hat on UL1699 40.4 , the carbonized path arc performance test.

Said NEMA task force admitted it's failure, and turned the matter over to UL , a highly unusual circumstance.

So we essentially have a listing without , or with a nefarious 'standard' at best.


~RJ~
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
It's bizarre how some of you jump to conclusions and shoot right from the hip without a complete understanding of your target. You claim there are no series tests and yet most of you have never even read or researched the standard. You then find out there is indeed series tests, two in fact, and then you shift your focus onto the cable specimen conditioning process and plant your distrust flag there. But again, you have missed the mark.

Haven't researched the standard yet I was the one that brought up 15kv being used, something you left out. That and the fact if 120 volts doesn't trip the AFCI after 10 seconds 15kv is re-applied.


The point contact arcing test simulates the instantaneous-type arcing which occurs at 120V but at much higher fault currents (75A-500A) as a result of the simulated ground-fault. The carbonized arc tests are a real-world simulation for damaged, aging, misused, and other stress-related conditions over time. At 120V and as little as 200mA, even minor damage to a conductor may result in arcing which could break down the insulation and potentially create carbon buildup around the conductors. This is called the "build-up" or "conditioning" stage. As voltage is applied to the high resistance but conductive path, the carbon burns away resulting in more arcing and more carbonized deposits. Combustible gases are also created by this process.

I dont see many situations in the real world where insulation and cooper is turned into a superheated soup sealed up in tape. The energy released involving 15kv at 30ma across a fraction of a milli meter is just unreal.

From a series arcing standpoint unless someone is physically making and then breaking a clean cut conductor under load tens of thousands of times over and over I cant imagine that much incident energy ever being subjected to a wire in the real world.


This repetitive cycle ultimately sustains itself to a point where the chain reaction produces enough energy to ignite the combustible gases and surrounding combustible materials.

Where is the evidence that this is responsible for hundreds of thousands of home fires? It has never been proven this takes place behind walls or to what degree let alone how many cases have lead to fire.



So, how do you reproduce this real-world event in the laboratory? The solution derived after literally thousands of hours of research and testing is the "conditioning" process outlined in the standard today; carbonized fault simulators. The fault simulators reproduce, in a very short period of time, exactly what occurs on real-world branch circuits in weeks, months and years. A good analogy would be water frozen into ice. You can freeze water slowly or you can freeze water quickly. Both methods produce ice.


Physically break/make of a broken conductor or accelerated thermal aging might have been a better option reflecting the real world, but then again those might just giveaway what it really takes to get dangerous arcing without the assistance of high voltage.

Also keep in mind flash frozen water takes on a different structure then water frozen over a period of time.




The AFCI is not tested on the conditioning voltages, but at rated voltage (120V). The AFCI can't and doesn't know if the hazardous arcing is a result of simulated or natural conditioning.

There are still 2 issues:

1. 120 volts is applied immediately after 15kv has altered the insulation and copper. Analogy would be an HID lamp where a 4kv igniter strikes a low voltage high current arc with only an open circuit ballast voltage of only 100. The 4kv pulse is gone, but the arc can now be sustained at a far lower voltage.

2. I would imagine relays cycling between the transformer and 120 volts would produce transients seen by the AFCI.

Also, are those relays even rated to handle 15kv?



The "test" performed in the video linked above is absurd and most certainly doesn't simulate a "real-world" condition that could result in fire. In fact, it more closely resembles non-hazardous arcing that occurs in normally operating appliances, motors and switches which would result in unwanted tripping of the AFCI device. The gentlemen conducting the test apparently hasn't read the standard either nor understands the physics of hazardous arcing.

A loose connection at a terminal seems far more plausible to me than 15kv.
 

bphgravity

Senior Member
Location
Florida
RJ & mbrooke, I love your enthusiasm. You both have incredible imaginations...

I have offered nothing but facts. You have offered nothing but baseless theories and innuendo. I have researched and studied every clause in the UL 1699 standard and currently serve as NEMA staff on the AFCI Task Force. You have never even read the standard and are basing your entire understanding of AFCI technology on ONE dissenting IEEE whitepaper and a YouTube video.

I know I am never going to convince either of you to accept and support the previous work and actions of NEMA, UL, and CMP-2 with regard to AFCIs, but perhaps you will now be inclined to become more engaged and in-tune with the current and future developmental and regulatory activities that are and will be taking place with AFCI technology.

Work will be getting underway on the UL STP shortly as there are a few significant enhancements coming to AFCI devices in the very near future. It's an exciting time to be in our industry. I hope you and a few of the others here on this Forum are capable of keeping a more positive and open-mind as we keep moving forward.

Happy Independence Day!
 

ActionDave

Chief Moderator
Staff member
Location
Durango, CO, 10 h 20 min from the winged horses.
Occupation
Licensed Electrician
RJ & mbrooke, I love your enthusiasm. You both have incredible imaginations...

I have offered nothing but facts. You have offered nothing but baseless theories and innuendo. I have researched and studied every clause in the UL 1699 standard and currently serve as NEMA staff on the AFCI Task Force. You have never even read the standard and are basing your entire understanding of AFCI technology on ONE dissenting IEEE whitepaper and a YouTube video.
You have offered nothing about how AFCI breakers do anything of value in real life, only what they do in the lab.
 

romex jockey

Senior Member
Location
Vermont
Occupation
electrician
We expect your response as posted Bryan, we also know we're being monitored ....

We know the manufacturers influence has infiltrated , much to the point where we seem to debating the monarchial rule of 1772.

But much like the Sons of Liberty 'we' meet in these smokey backrooms , something that can not be bought , manipulated , or monopolized as easily

Our independence day will come when your ilk is held accountable

You can fool all the people some of the time, and some of the people all the time, but you cannot fool all the people all the time.

~RJ~
 

bphgravity

Senior Member
Location
Florida
You have offered nothing about how AFCI breakers do anything of value in real life, only what they do in the lab.

Exactly. I was asked to explain how series arcing is tested in accordance with the standard. It's not my fault if you guys are asking the wrong questions or can't handle the correct answers. It's quite pathetic actually.
 

bphgravity

Senior Member
Location
Florida
We expect your response as posted Bryan, we also know we're being monitored ....~RJ~

Actually, I don't think you guys did expect my responses. I have been able to answer every one of your questions, even the ridiculous ones. You want to believe so badly that something nefarious is going on that you resort to personal insults and slanderous comments in lieu of anything productive or substantiated.

I really do feel your paranoia and skepticism has gotten the best of you and is clouding your intellect. That's too bad. Since I don't know your age, I can't exactly tell if this is due to youthful immaturity or perhaps stubborn ignorance. Fortunately, both are curable.

Oh, one more bit of advice. The Romex® brand is a federally registered trademark owned by Southwire Company, LLC who vigorously monitors and protects the use of the Romex® brand in North America and around the world. I really hope you received written permission from the company to use their trademark as your Forum name. At least you now have something real to be paranoid about... ;)
 

romex jockey

Senior Member
Location
Vermont
Occupation
electrician
40.4

40.4

The preparation of the test samples is very complicated, and
dangerous.

The following words were taken from today’s UL1699 AFCI
Standard, Section 40.4 Carbonized path arc clearing time test


40.4.2 Specimens of Type SPT-2 16 AWG (1.3 mm2) cord are
to be prepared as follows:

a) The cord specimens are to be cut to a minimum length of 8
inches (203 mm) and the individual wires separated at
each end of the cord specimen for 1 inch (25.4 mm).

b) The insulation across both wires is to be slit 2 inches (50.8
mm) from one end to a depth to expose the conductors
without severing any strands.

c) The slit in the insulation is to be wrapped with a double layer
of electrical grade black PVC tape and overwrapped with a
double layer of fiberglass tape.

d) The conductors are to be stripped at the end farthest from
the slit approximately 1/2 inch (12.7 mm) for connection to
the test circuits.

40.4.3 The cord specimens shall be conditioned using a
supply of sufficient voltage(s) and current(s) to rapidly
pyrolyze the insulation at the slit in the cord and create a
carbonized conductive path across the insulation between
the cord conductors. The carbonized path shall be
considered complete if a 100 W incandescent lamp in
series with the path draws 0.3 A or can start to glow at
120 V. The following steps are one method that is known to
produce such a carbonized path.

So the wire sample is prepared as a parallel, not a series,
fault.


Author’s note: Wire preparation is dangerous. Two
transformers are required, 7kV @ 30mA and 2kV @ 300mA.


~RJ~
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
RJ & mbrooke, I love your enthusiasm. You both have incredible imaginations...

I have offered nothing but facts. You have offered nothing but baseless theories and innuendo. I have researched and studied every clause in the UL 1699 standard and currently serve as NEMA staff on the AFCI Task Force. You have never even read the standard and are basing your entire understanding of AFCI technology on ONE dissenting IEEE whitepaper and a YouTube video.

You are just assuming Ive only read one whitepaper and seen one YouTube video, and yes that would be more convenient. But trust me, I want to get a better understanding of this technology. The more I research, the more I look at this history, the more I read documents, the more I am beginning to see a gap between advertised claims and real world data.


Perhaps what will settle doubts for me, is real world evidence that arc faults are responsible for so many dwelling fires.



I know I am never going to convince either of you to accept and support the previous work and actions of NEMA, UL, and CMP-2 with regard to AFCIs, but perhaps you will now be inclined to become more engaged and in-tune with the current and future developmental and regulatory activities that are and will be taking place with AFCI technology.


I have no doubt people have done all this work, I respect that, and its not the issue. The issue being is all this worth it for a typical dwelling? Again, show me how research and data analysis concluded arcing is behind so many electrical fires.



Work will be getting underway on the UL STP shortly as there are a few significant enhancements coming to AFCI devices in the very near future. It's an exciting time to be in our industry. I hope you and a few of the others here on this Forum are capable of keeping a more positive and open-mind as we keep moving forward.

All that may be worthless if arc faults are not a major issue at dwelling voltages.


My advice to you, and others, is to study the most mature AFCI technology: high impedance fault detection for MV applications. This technology is by far the advanced offering a wealth of information.


Happy Independence Day!

Happy July 4th! :)
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
Exactly. I was asked to explain how series arcing is tested in accordance with the standard. It's not my fault if you guys are asking the wrong questions or can't handle the correct answers. It's quite pathetic actually.

Actually it was you who hid important facts from your first description regarding series arc testing. From what I am seeing this mentality is rampant...


In no way am I saying any of this is untrue, yes it takes place inside lab testing, however it has yet to be proven how, and if such tests truly reflect the real world.

Everything in so far tells me there is a missing link between fire statistics and the advertised claim "arc faults are behind dwelling fires"
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
...

I have offered nothing but facts. ...

Happy Independence Day!
The problem with that for me is that you represent the industry, and I have a serious mistrust of any information from that source on the AFCI issue. That is because they lied to us from day one on this issue. The original proposals said that they had a device that would do what they now tell use a combination device will do...the only problem was that those original proposals predated the combination AFCI by about 13 years.

The industry has given me NO reason to believe anything they say about AFCIs.

As far as arcing and fires, there is little evidence that they cause many fires, but there is a huge amount of information that shows joule heating at poor connections do cause many fires, and even UL says that AFCI devices cannot detect joule heating (also known as a poor connection, a high resistance connection or a glowing connection).
 

iwire

Moderator
Staff member
Location
Massachusetts
The problem with that for me is that you represent the industry, and I have a serious mistrust of any information from that source on the AFCI issue. That is because they lied to us from day one on this issue. The original proposals said that they had a device that would do what they now tell use a combination device will do...the only problem was that those original proposals predated the combination AFCI by about 13 years.

The industry has given me NO reason to believe anything they say about AFCIs.

As far as arcing and fires, there is little evidence that they cause many fires, but there is a huge amount of information that shows joule heating at poor connections do cause many fires, and even UL says that AFCI devices cannot detect joule heating (also known as a poor connection, a high resistance connection or a glowing connection).

Don,

I would be so happy if anyone from NEMA or a manufacturer or the CMP could take quick look at the statistics involving fires and how AFCIs would change those numbers that you put together and at that point try find a compelling reason other than sales to require them.
 

bphgravity

Senior Member
Location
Florida
So the wire sample is prepared as a parallel, not a series,
fault.


~RJ~

Again, your hanging your hat on the opinion and analysis of one person. The author is wrong. The arcing fault current is in series. This is the exact exhibit from the standard: (Follow the flow of current - it has but one path)
 

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romex jockey

Senior Member
Location
Vermont
Occupation
electrician
Again, your hanging your hat on the opinion and analysis of one person. The author is wrong. The arcing fault current is in series. This is the exact exhibit from the standard: (Follow the flow of current - it has but one path)

Please refer to UL1699 40.4 in it's entirety

thx

~RJ~
 

romex jockey

Senior Member
Location
Vermont
Occupation
electrician
Don,

I would be so happy if anyone from NEMA or a manufacturer or the CMP could take quick look at the statistics involving fires and how AFCIs would change those numbers that you put together and at that point try find a compelling reason other than sales to require them.

I think you'll find the old adage about stats rather applicable ,once you've delved into it Iwire

~RJ~
 
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