AFCI (yes again)

[George Stolz]

You've made your case, the opposing argument has made it's case, and this forum will likely never settle the issue, if there even is one to settle.

Against my better judgment, I am re-opening the thread as mbrooke has requested.

I request that you gents angle for a point.

 

[MasterTheNEC]

Well, that's kind of a problem because 95% of this thread consists of you hinting and winking and generally avoiding any specifics while stating you'd love to go into specifics. You'd love to discuss details of a technical nature as to why AFCI is the best thing since the first coming, but you don't want to discuss details. You'd love to name-drop whoever toured you through the factory, but you don't want to. You seem to have a conflict here which I am remedying now.


Again, with your internal struggle. You don't want to run him down, yet you believe everything he has claimed is hog-wash. But, alas, you don't want to go into details as to why, aside from some unnamed source "in the know" told you, and that statement is supposed to carry weight.



That is one point you've made abundantly clear. Over, and over, and over, and over...

You've made your case, the opposing argument has made it's case, and this forum will likely never settle the issue, if there even is one to settle. This is a vapid thread that has run it's course. In closing, I wish to thank all participants for keeping it civil.

-George

The statements I have made are very clear but you choose not to understand them or consider them. Nothing in my statements discredits Mr. Engle, read it again rather than jumping to closing threads.

It serves no purpose to expose Engineers that disagree with Mr. Engles points in his whitepaper , nothing about the Holt forum is a trial George. I have indeed said over and over that opinions are of their own but you may choose to ignore that statement in your heavy handed mentality of thread closing.

You know what.....if we ( the debaters) choose to go into technical details thats a prerogative of the posters and not something you have control over as a moderator...but then again as usual those rules may change. The technical aspects of the workings of AFCI's have been discussed. The mention of algorithms, shoulders and level of half cycle detection along with various frequency aspects to the detection are all part of the technology but each manufacturer does this differently. I am not an AFCI expert as I have stated before and I am only trying to bring my aspects of what I do know but you wish to discredit it as having no merit to the conversation and that is not your choice...you Moderator and only that in my opinion.

You again obviously did not read all the posts before making an attempt to belittle my statements and then call for a civil debate...The debate between Mbrooke and myself has been a good debate on the issues so leave it as it should be...opinions and debates unless that is against the forum rules....or your rules?

mbrooke - I have no problem with emailing or PM you offline and continuing the discussion because it appears to me here that it would never be fair and balanced on this forum. I have tried to address your questions but then again in my schedule of attending the NFPA Meetings and CMP panels I quite possibly have not addressed all your concerns....and I do want to, I have nothing to hide in my personal beliefs and what I have witnessed in terms of tests at a manufacturers facility but it is apparent it would not be appreciated here.

The manufacturer of at least (2) companies have informed me personally that the GFP is also affording the microprocessor some benefit of internal protection that could cause a problem to their circuitry internal to the device. The true nature of the GFP is not the main purpose of that function and not why it is installed, it was just expressed that it's very nature lends to added protection to the microprocessor. There real intent of the GFP was to meet the UL 1699 tests and to aid in detecting arcs within nonmetallic- sheathed cable and is why they (2- companies) continue to keep the GFP in their AFCI Circuit Breakers.

You keep asking me to define how it protects the circuitry and I can't go into more details on that because it was not the original basis of the manufacturers reason, it was stated that it adds some additional protection to the processor by the engineer who oversees the AFCI development but thats all I can tell you on that as a statement, it was never really supposed to be germane to the conversation i just mentioned what was expressed to me.

But again to address George....Who is struggling with a statement regarding Mr. Engle?..I respect the man and what he did, I am just saying that from the 2012 IEEE Conference where the white paper was presented to today, many industry engineers disagree with his some of his statements (not all of his statements) and based on my conversations and listening to their reasons for disagreement...I happen to agree. However, what purpose does it serve to tell this forum all the engineers names that work for both the original company Mr. Engle worked for and other manufacturers who specialize in the technology.

Here is my suggestion....I would love to continue the discussion mbrooke so please PM your contact info and we can continue the discussion as it is clear to me the desire is to have this thread closed.

 

[MasterTheNEC]

Members-

It has come to my attention that my posts on this subject may have taken a jab at the moderators and Mr.Holt. I truly apologize if that is how it was conveyed. The statement I made about a "grain of salt" towards Mike was not a jab at Mike at all as I have the highest level of respect for him. The statement was towards a posting of Mike's original position on AFCI's while knowing that position changed with a visit to Eaton....and nothing more, if it came across as such i truly apologize for that as it was not the intent.

George- You do a great job here and I do apologize as well if my comments offended you and they were probably posted in my poor judgement as you and the other moderators are charged with keeping the sanity of the thread and chances are it did ramble on without substantiation...I apologize again for laying claims against your judgement.

in terms of technical data, I am not sure how technical the discussion was intended to get so I apologize if the rebutted comments in our discussion lacked substance, I just did not put together how detailed we needed to go but as stated we can go deeper, just how deep because the detection methods, other than cross over points, shoulder points, half-cycle sustained conditions and frequency detection are all technical aspects of the detection and filtration properties of the AFCI. I never claimed to be an expert on them, I just wanted to post what I knew about them....nothing more.

obviously Mbrooke has much more knowledge that me on the subject and that is why I am still in the thread as I want to learn also because I do have the ability to bend the ear of the manufacturers experts to help dig into what others feel are problems....let's fix what others dislike about them. However, change is not going to come unless we talk about it and send the message where it is needed.

as for Dr.Engles document , a great man with a lot to say. I only stated that many others (who it would be unfair to them to post their names when they are not part of the thread)feel differently about some, not all, of the data. Mr. Engels document was posted so it is fair game to discuss and we will indeed take this off line.

so with that said....I again Apologize to George and anyone else my statements may have offended, it was not my intend to cause anything otherwise and was my poor judgement. You mods here do a great job....!

I will end my responses to this thread with...PM me mbrooke and we will continue and I may be able to connect you with some AFCI Folks who can better answer your questions.

 

[mbrooke]

Members-

I am still in the thread as I want to learn also because I do have the ability to bend the ear of the manufacturers experts to help dig into what others feel are problems....let's fix what others dislike about them. However, change is not going to come unless we talk about it and send the message where it is needed.

I think that is great I feel the same way in that if we can collectively discuss our woes and experiences AFCIs can be improved. Being able to rely info back is a great advantage to the industry.

I will end my responses to this thread with...PM me mbrooke and we will continue and I may be able to connect you with some AFCI Folks who can better answer your questions.

I will send a PM. Thank you for the kind words as well as the offer

 

[George Stolz]

I try not to leave my feelers sticking out, or they would get snapped off. I appreciate the comment, and hope it's the last such exchange we have.

-George

 

[kwired]

Is Mr. Engle way smarter than me...YEP......never once wish to discredit him at all. Just that his opinions are only that in terms of his white papers theories and since that time many in the field who do this for a living have stated that his assumptions are incorrect, which is all I am saying.

Both sides of this argument seem to be full of assumptions is what I am seeing - makes it hard to pick a side and you revert to what you feel safe with. As I have said before I am for the things that AFCI is supposed to be able to do. I am not fully convinced they can do everything they are supposed to do, or at least that all the bugs haven't been worked out of them yet. Continued problems - even if there are people out there that can figure them out, doesn't do any good to a consumer that gets frustrated with the seemingly unnecessary tripping, and gets tired of throwing money at a problem and not getting any useful (in their mind) results. This presents all kind of perceived trouble with the product and gives bad reputations to the product and or the people requiring it's use, and on top of that they want to sell a product that costs several times what the product it replaces costs, that don't go over well with users either when they see nothing but trouble after spending extra on something that gives them all this trouble.

Consumers can and will spend money, but they want something they will notice in a positive way in return, and power outages for whatever reason does not go over well with consumers of electrically operated stuff and many would spend twice as much for a device that doesn't have these kind of "problematic tripping issues" so the focus needs to be on eliminating as many "false trips" as possible. Some of that may involve more education on what is a true simpler problem and what is complex enough the device needs redesign/reprogramming for, and what do we do with existing units that have been superseded - after all we spent a lot on them in the first place, and only a short time later it may have been updated to overlook a certain signature that has now been deemed acceptable.

I have gotten recall letters for other products, even been paid to repair/replace such products but never one for updating an AFCI with one that will work better then the previous generation they found some fixes for. Space is somewhat of an issue with these but I think a good design would involve interface that allows for firmware changes somehow - maybe even more closer look at what is going on with an external devices to help with the troubleshooting process when there is a more complicated tripping issue, then maybe they are closer to a product I am more on board with. May cost more, but at least is something that is more "troubleshootable" instead of what does go on which is always replace the unit, still trips, what next? Guess we don't know what the problems is, lets put a standard breaker in it's place. Consumers seem to love gadgets, why not a monitor that connects to all those AFCI's and gives you more details of what they are doing, and maybe a better understanding of what may be wrong with their wiring system if it can tell you more information on what it is seeing and why it is rejecting some particular condition?

 

[kwired]

Seems the thread was closed while I was composing my last post, yet reopened before I submitted it

 

[mbrooke]

I think this is makes some fascinating points I never considered before:




http://paceforensic.com/pdfs/Circuit_Breakers_The_Myth_of_Safety.pdf

 

[don_resqcapt19]

I think this is makes some fascinating points I never considered before:
http://paceforensic.com/pdfs/Circuit_Breakers_The_Myth_of_Safety.pdf

There was a proposal sometime in the last few code cycles that would have required 15 and 20 amp breakers used in dwelling units to have a 75 amp instantaneous trip setting. It was not accepted. As I recall the proposal stated that UL standard for breakers does not even require that the breaker have an instantaneous trip function.

 

[mbrooke]

There was a proposal sometime in the last few code cycles that would have required 15 and 20 amp breakers used in dwelling units to have a 75 amp instantaneous trip setting. It was not accepted. As I recall the proposal stated that UL standard for breakers does not even require that the breaker have an instantaneous trip function.

That is interesting in that while CMP can not control UL standards they can force requirements. IE, "All residential single pole breakers feeding 15 and 20amp home runs shall have a instantaneous magnetic pick up of 75amps"

IMO instantaneous trip should be mandatory. In Europe earth fault loop impedance requirements essentially force breakers to have it. But as stated here a low magnetic trip has another benefit in the prevention of electrical fires. Branch feeder AFCI trip out at 75amps for a parallel fault, so in theory a low MT would do the same. 30ma GFP would catch the hot to ground arcs. At the branch circuit level this would not be a major concern in that large motor loads are rare.


Square D QO and homeline single pole breakers are already there in that they have a MT of 5 to 6 times the handle rating where as double pole QOs and HOMs have a MT starting at 10 and over the handle rating allowing AC units and large 240 volt motor appliances to have no issue.




I believe this article also makes some other really good points. It brings up over driven staples as a factor, in fact the article goes as far to say that fires from branch circuit overloads are not a concern since wiring already has so many safety factors built in. This again goes back to the original electrician. If circuits were meggered prior to energizing would such a defect be caught?


Further in theory: if a low MT helps a parallel fault, a 1 amp fuse on a lamp cord with an instantaneous blow of 13 amps would catch a parallel arc immediately.

 

[don_resqcapt19]

...
I believe this article also makes some other really good points. It brings up over driven staples as a factor, in fact the article goes as far to say that fires from branch circuit overloads are not a concern since wiring already has so many safety factors built in. ...

Yet some testing done by UL for their report titled "Influence of Damage and Degradation on Breakdown Voltages of NM Cable" (November 2012) indicates that hammer damage and over driven staples are not likely to cause a fire.

...Two types of damage scenarios were investigated in this work, representative of the information found in the literature, associated with installation activities: (i) inadvertent hammer blow to the cable outer jacket; and (ii) compression of the insulation from over-driving staples through the outer jacket.
...
The test results indicate that the probability of sustained arcing and ignition is low for hammer-damaged NM cable. The results also show that though a carbonized path may eventually be formed, this path formation did not lead to subsequent ignition of the cable jacket or surrounding materials, and self-extinguished after a short period of arcing. ...

 

[don_resqcapt19]

The proposal was proposal 10-55 for the 2008 code. Here is the proposal.

10-55 Log #2977 NEC-P10 Final Action: Reject
(240.87)
______________________________________________________________
Submitter: Paul A. Keleher, Paul Keleher Electrical Services
Recommendation: Add text to read as follows:
240.87 Defined Instantaneous Trip (DIT) Circuit Breakers.
(A) Definitions. The nominal instantaneous trip current is 11 times the rated current of the circuit breaker. A standard circuit breaker manufactured with a fixed instantaneous pick-up setting shall open the circuit within 1/2 cycle of being subjected to the nominal instantaneous trip current or greater, with an acceptable variation in the listing test range of 130-210 amperes.
(B) Circuit Breakers Installed in Dwelling Units. Standard circuit breakers installed in a dwelling unit to protect branch circuits rated 20 amperes or less at 120 volts to ground shall be of the DIT type.
(C) Marking. Any standard circuit breaker installed in accordance with 240.87(B) shall be marked by the manufacturer such that the letters ?DIT? will be clearly visible after installation.

The substantiation was somewhat long so I did not post it.

I see that it proposed a higher trip current than what I had posted previously.

 

[mbrooke]

Thanks for the info! I will read up on it

 

[marmathsen]

210.12(A) and heaters

210.12(A) and heaters

Article 210.12(A) explicitly says "All 120-volt, single-phase, 15- and 20-ampere branch circuits supplying outlets or devices installed in dwelling unit kitchens, family rooms.....[etc.] shall be protected by [AFCI protection]". If you take that literally, it is saying that ANY DEVICE that is 15 or 20A 120Vand exists in those rooms would require AFCI protection. Would any of you disagree that a permanently installed electric heater installed in any of those rooms and is fed by a 15 or 20A 120V circuit would require AFCI protection as well? I don't see anything in Article 424 or 210 that would suggest otherwise. Thoughts?

Rob

 

[ActionDave]

Article 210.12(A) explicitly says "All 120-volt, single-phase, 15- and 20-ampere branch circuits supplying outlets or devices installed in dwelling unit kitchens, family rooms.....[etc.] shall be protected by [AFCI protection]". If you take that literally, it is saying that ANY DEVICE that is 15 or 20A 120Vand exists in those rooms would require AFCI protection. Would any of you disagree that a permanently installed electric heater installed in any of those rooms and is fed by a 15 or 20A 120V circuit would require AFCI protection as well? I don't see anything in Article 424 or 210 that would suggest otherwise. Thoughts?

Rob

I would say that a heater is utilization equipment not a device.

 

[mbrooke]

Article 210.12(A) explicitly says "All 120-volt, single-phase, 15- and 20-ampere branch circuits supplying outlets or devices installed in dwelling unit kitchens, family rooms.....[etc.] shall be protected by [AFCI protection]". If you take that literally, it is saying that ANY DEVICE that is 15 or 20A 120Vand exists in those rooms would require AFCI protection. Would any of you disagree that a permanently installed electric heater installed in any of those rooms and is fed by a 15 or 20A 120V circuit would require AFCI protection as well? I don't see anything in Article 424 or 210 that would suggest otherwise. Thoughts?

Rob

Being literal I would say the intent is that, anything that's 120 volts, 15 or 20amps.

At the rate things are going, and with the rumors I hear, it will not at all surprise me if in 10 years EVERYTHING in a dwelling will require AFCI.


But, mark my words, electrical fires will recede a bit, but never disappear because glowing connection are not being addressed.

 

[kwired]

Article 210.12(A) explicitly says "All 120-volt, single-phase, 15- and 20-ampere branch circuits supplying outlets or devices installed in dwelling unit kitchens, family rooms.....[etc.] shall be protected by [AFCI protection]". If you take that literally, it is saying that ANY DEVICE that is 15 or 20A 120Vand exists in those rooms would require AFCI protection. Would any of you disagree that a permanently installed electric heater installed in any of those rooms and is fed by a 15 or 20A 120V circuit would require AFCI protection as well? I don't see anything in Article 424 or 210 that would suggest otherwise. Thoughts?

Rob

The "or devices" was recently added to 2014 -the biggest change for most people here now means a switch controlling an outdoor load needs AFCI protection if the switch is indoors in a room that is on the list for AFCI requirements.

What has not changed from nearly the beginning of AFCI requirements being in the NEC is that it requires protection of "outlets" that are 15/20 amp - 120 volts. A permanently wired appliance still has an associated "outlet" per the NEC.

 

[al hildenbrand]

Would any of you disagree that a permanently installed electric heater installed in any of those rooms and is fed by a 15 or 20A 120V circuit would require AFCI protection as well?

I don't disagree. I see the AFCI protection of any hardwired 15 or 20 Amp 120 Volt Utilization Equipment as being required for several Code cycles, ever since "receptacle outlet" was changed to "outlet" in 210.12. That was over a decade ago.

Quite simply, an item of Utilization Equipment that is hardwired, in order to be energized, is connected to the Premises Wiring (System) at an "Outlet", which, when hard wired, is the termination (wirenut) between the Branch Circuit conductors and the Utilization Equipment internal conductors that are part of its factory assembly.

 

[marmathsen]

I don't disagree. I see the AFCI protection of any hardwired 15 or 20 Amp 120 Volt Utilization Equipment as being required for several Code cycles, ever since "receptacle outlet" was changed to "outlet" in 210.12. That was over a decade ago.

Quite simply, an item of Utilization Equipment that is hardwired, in order to be energized, is connected to the Premises Wiring (System) at an "Outlet", which, when hard wired, is the termination (wirenut) between the Branch Circuit conductors and the Utilization Equipment internal conductors that are part of its factory assembly.

Your response referencing the definitions of both "device" and "utilization equipment" made me think I should look at those more closely at those definitions.

"Device. A unit of an electrical system, other than a conductor, that carries or controls electric energy as its principal function"
Handbook commentary for Device - "Switches, circuit breakers, fuseholder, receptacles, attachment plugs, and lampholders that distribute or control but do not consume electrical energy are considered devices. Devises that consume incidental amounts of electrical energy in the performance of carrying or controlling electricity - such as a switch with an internal pilot light, a GFCI receptacle, or a magnetic contactor - are also considered devices. Although conductors are units of the electrical system, they are not devices."

"Utilization Equipment. Equipment that utilizes electric energy for electronic, electromechanical, chemical, heating, lighting or similar purposes."

After looking at these two definitions more closely and especially the Handbook's commentary stating "...that distribute or control but DO NOT CONSUME ELECTRICAL ENERGY..." I no longer feel that a heater by itself would be considered a device and in turn would not require AFCI protection. However, here's the rub...I would however consider a wall mounted thermostat utilizing 120V to be a device and WOULD require AFCI protection, would it not?

 

[al hildenbrand]

I no longer feel that a heater by itself would be considered a device and in turn would not require AFCI protection.

Don't forget the Article 100 Definition of Outlet as well as Premises Wiring (System). The wiring internal to utilization equipment (hardwired heater, hardwired smoke detector) is not part of the branch circuit. The wiring internal to the utilization equipment is connected to the branch circuit at an Outlet.