AFCI Breakers

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peter d

Senior Member
Location
New England
It was on the market. The original branch circuit/feeder type were the first AFCIs. I have no idea why they were called branch circuit/feeder as they only make them with 15 or 20 amp ratings.

The original AFCI rule was in the 1999 code with a 2002 effective date. The combination type was in the 2005 code with an effective date of 2008.

All of the combos when they first hit the market had the GFP circuit. As far as I know only GE has removed it from all of their AFCIs, Eaton has removed it from some of theirs. I believe the rest still have GFP.

The point Joe Engel was making is that is should be required as part of the AFCI technology, and it is not. He was heavily in favor of it, for obvious reasons.

If the AFCI incorporates GFPE, fine. I can accept it then because it has some value, at least. But clearly the arc discrimination technology is a joke.
 

Sierrasparky

Senior Member
Location
USA
Occupation
Electrician ,contractor
The point Joe Engel was making is that is should be required as part of the AFCI technology, and it is not. He was heavily in favor of it, for obvious reasons.

If the AFCI incorporates GFPE, fine. I can accept it then because it has some value, at least. But clearly the arc discrimination technology is a joke.


Well what I also gathered was that the UL made a test for the product not a test for the problem and if the product actually worked.

I could form a electrical think tank and design products, then convince the CMP to adopt the idea and then the product. Then design a test around the product but not a test that test for the protection of the problem.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
The point Joe Engel was making is that is should be required as part of the AFCI technology, and it is not. He was heavily in favor of it, for obvious reasons.

If the AFCI incorporates GFPE, fine. I can accept it then because it has some value, at least. But clearly the arc discrimination technology is a joke.
The GFP was never required by the UL standard for AFCIs, but my understanding is that, with the original AFCIs, they could not pass the required tests without the GFP. Apparently they have found a way to pass the tests without the GFP now.
 

kwired

Electron manager
Location
NE Nebraska
That is because most of their articles are written by the manufacturers that also advertise in the magazines.

The last good trade magazine was EC&M when it was run by Joe McPartland and you had to pay for a subscription.
And the magazines are free to nearly all subcribers - it is the advertisers that pay for these publications, I have never seen anything in any of those magazines that even slightly puts down any product that is in current production. They may mention what was wrong with things from the past though, especially if something (presumably) new and better has come along.
 

bphgravity

Senior Member
Location
Florida
One would imagine my request a no brainer for a NFPA, IAEI, ICC, BOAF, and LPI member Bryan. ~RJ~

Okay, relax... I didn't know I had a deadline. And I am not exactly sure what my professional memberships have to do with anything?


Anyway, the UL 1699 standard currently has (4) arc fault detection tests. Two of the tests simulate arcing in parallel with the load, the other two simulate arcing is series with the load. The carbonized path arc ignition, interrupting, and clearing time tests are non-contact simulations where the conductors are prepared and intentionally damaged prior to the circuit being energized. The point contact arc test is an active-contact test where the damage to the conductors occurs while the circuit is energized and under load conditions.

The carbonized path arc interrupting test and the point contact test are the two parallel tests. While extremely interesting and important, you have specifically asked about the series tests. So, I won’t go into any more detail about these two tests. That leaves us with the two series arc tests; the carbonized path arc ignition test and the carbonized path arc clearing time test.

Let's start with the arc ignition test, known as the "cotton test". An 8-inch length of NM-B cable is properly terminated to the AFCI device and a resistive load. A series cut is made all the way through the ungrounded conductor without damaging the insulated grounded conductor. The damaged section is wrapped with tape followed by surgical cotton. Example photos are provided below. The circuit is then energized at rated voltage. The test is performed on three cable samples at each current level; a 5A load, 10A load, at the rated current of the AFCI (15A, 20A), and at 150% of rated current. The same exact procedure is repeated with the cut on the grounded circuit conductor. The AFCI has to interrupt the load prior to ignition of the cotton and within 5-minutes or the AFCI fails.

The clearing time test cannot be passed with branch/feeder AFCIs. Combination and Outlet Branch Circuit AFCIs must pass this test. For this test, 16 AWG SPT-2 flexible cord is connected in series with the AFCI device and downstream from the load. See the attached diagram. The insulation across both wires is to be slit 2-inches to a depth to expose the conductors without severing any strands. The damaged section is wrapped with tape. The circuit is energized at the rated voltage of the AFCI and at the 5A, 10A, rated current, and 150% rated current loads. Each AFCI is tested with three cord specimens at each current level. For this test, it’s all about the time it takes for the AFCI to clear the arc fault ranging from 1 second at 5A to less than 200 milliseconds at 150% of rated current. Different switching configurations are also tested. For instance, the AFCI is to be closed on the fault and allowed to open the circuit. The test is to be repeated by closing a switch on the load side of the AFCI. Each configuration has a specified clearing time in order for the AFCI to pass.

So there you have it. Nothing to hide. Dr. Engel designed an elegant product and innovative testing procedures. It didn't pass muster for the UL/CPSC team that completed the first investigations. This was confirmed by the UL STP that has verified and approved the standard as written today. Every meeting and vote was made in the sunshine and recorded. There is simply nothing special about the development of the UL 1699 standard that doesn't occur with the development of every other UL standard. For every supporting view, there is an opposing view.

Statements made in an IEEE whitepaper doesn't necessarily mean it is true and factual. I have read plenty of IEEE whitepapers on non-conventional lightning protection systems (ESE, CTS, DAS) that make all sorts of claims just like Dr. Engel's does. Guess what, there is no conspiracy occurring with the NFPA 780 or UL96 standards either.

Here's the best part. Each and every one of you can submit a proposal to modify the UL 1699 standard. Like the development of the NEC, the proposal HAS to be acted on by the STP and it's all open to public scrutiny and comment. Better yet, each and every one of you can apply to serve on the UL 1699 STP. This way you can put all your great ideas to work... Just saying.
 

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  • AFCI - Clearing Time Test.jpg
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mbrooke

Batteries Included
Location
United States
Occupation
Technician
Okay, relax... I didn't know I had a deadline. And I am not exactly sure what my professional memberships have to do with anything?


Anyway, the UL 1699 standard currently has (4) arc fault detection tests. Two of the tests simulate arcing in parallel with the load, the other two simulate arcing is series with the load. The carbonized path arc ignition, interrupting, and clearing time tests are non-contact simulations where the conductors are prepared and intentionally damaged prior to the circuit being energized. The point contact arc test is an active-contact test where the damage to the conductors occurs while the circuit is energized and under load conditions.

The carbonized path arc interrupting test and the point contact test are the two parallel tests. While extremely interesting and important, you have specifically asked about the series tests. So, I won’t go into any more detail about these two tests. That leaves us with the two series arc tests; the carbonized path arc ignition test and the carbonized path arc clearing time test.

Let's start with the arc ignition test, known as the "cotton test". An 8-inch length of NM-B cable is properly terminated to the AFCI device and a resistive load. A series cut is made all the way through the ungrounded conductor without damaging the insulated grounded conductor. The damaged section is wrapped with tape followed by surgical cotton. Example photos are provided below. The circuit is then energized at rated voltage. The test is performed on three cable samples at each current level; a 5A load, 10A load, at the rated current of the AFCI (15A, 20A), and at 150% of rated current. The same exact procedure is repeated with the cut on the grounded circuit conductor. The AFCI has to interrupt the load prior to ignition of the cotton and within 5-minutes or the AFCI fails.

The clearing time test cannot be passed with branch/feeder AFCIs. Combination and Outlet Branch Circuit AFCIs must pass this test. For this test, 16 AWG SPT-2 flexible cord is connected in series with the AFCI device and downstream from the load. See the attached diagram. The insulation across both wires is to be slit 2-inches to a depth to expose the conductors without severing any strands. The damaged section is wrapped with tape. The circuit is energized at the rated voltage of the AFCI and at the 5A, 10A, rated current, and 150% rated current loads. Each AFCI is tested with three cord specimens at each current level. For this test, it’s all about the time it takes for the AFCI to clear the arc fault ranging from 1 second at 5A to less than 200 milliseconds at 150% of rated current. Different switching configurations are also tested. For instance, the AFCI is to be closed on the fault and allowed to open the circuit. The test is to be repeated by closing a switch on the load side of the AFCI. Each configuration has a specified clearing time in order for the AFCI to pass.

So there you have it. Nothing to hide. Dr. Engel designed an elegant product and innovative testing procedures. It didn't pass muster for the UL/CPSC team that completed the first investigations. This was confirmed by the UL STP that has verified and approved the standard as written today. Every meeting and vote was made in the sunshine and recorded. There is simply nothing special about the development of the UL 1699 standard that doesn't occur with the development of every other UL standard. For every supporting view, there is an opposing view.

Statements made in an IEEE whitepaper doesn't necessarily mean it is true and factual. I have read plenty of IEEE whitepapers on non-conventional lightning protection systems (ESE, CTS, DAS) that make all sorts of claims just like Dr. Engel's does. Guess what, there is no conspiracy occurring with the NFPA 780 or UL96 standards either.

Here's the best part. Each and every one of you can submit a proposal to modify the UL 1699 standard. Like the development of the NEC, the proposal HAS to be acted on by the STP and it's all open to public scrutiny and comment. Better yet, each and every one of you can apply to serve on the UL 1699 STP. This way you can put all your great ideas to work... Just saying.



Since when is the typical residential utilization voltage 15,000 volts? :blink::blink:
 

Tony S

Senior Member
I’ve tested 600/1000V grade cable to 17.5KV DC. Carefully formed terminations with no kinks or sudden bends in the length of the test piece. The only reason I stopped at 17.5KV is that’s as far as my test rig would go.

What I’m alluding to is a test specimen will prove whatever you want it to prove.
 

bphgravity

Senior Member
Location
Florida
That STP is not looking for new members and neither is 1699B for the DC AFCI.

The STPs have regular turn-over. The more popular product standards like UL 943 and UL 1699 are harder to get on. The same applies to the NEC. CMP 1, 2, and 5 are rather popular and hard to get a spot on.

The point is to get involved and participate in the process. If you can't get on the STP, at least sign-up to receive meeting alerts, get on the UL Program Managers email list, review and comment on proposals, ask to be on task groups, etc, etc, etc...
 

romex jockey

Senior Member
Location
Vermont
Occupation
electrician
The 15 kV, 30 mA current source is for creating a carbonized conductive path across the insulation of the cable specimens. The actual tests are at 120 VAC.

Rather depressing that you had to be prompted to let the cat outta the bag here Bryan

Yet it is the bottom line.....

They are creating a path, i.e.-parallel ,with means only mother nature could introduce in a residence

~RJ~
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
The 15 kV, 30 mA current source is for creating a carbonized conductive path across the insulation of the cable specimens. The actual tests are at 120 VAC.

The voltage drops to 120 volts, but immediately after 15,000 volts, which I would imagine is re-applied if nothing happens. I am not sure why you left that part out of your original description as its an essential part of the test in order to induce an arc signature condition.


But that leads me to further question arc faults, as I doubt a sustained 15,000 volts 60Hz sine wave is common in residential wiring.
 

bphgravity

Senior Member
Location
Florida
Rather depressing that you had to be prompted to let the cat outta the bag here Bryan

There is no cat and there is no bag? The UL 1699 standard is a published document available to the public. There are complete details of the arc fault tests all over the internet, including one by Mike Holt himself.

They are creating a path, i.e.-parallel ,with means only mother nature could introduce in a residence

~RJ~

I'm not sure I follow you here. The arc fault currents in both tests are in series, not parallel. The first test described indicates the AFCI will open to clear the series fault prior to the ignition of a combustible material surrounding the cable, and the second test described indicates the AFCI will open the series fault in a specified time. it's that simple.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
The 15 kV, 30 mA current source is for creating a carbonized conductive path across the insulation of the cable specimens. The actual tests are at 120 VAC.
So how is that carbonized path created in the real world? Also I fail to understand how a carbonized path creates an arc. To me a carbonized path is just that...a conductive path. I though arcs happen only when electricity travels from one point to another without a physical path....something that is not even possible at US dwelling unit voltages.
 
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