ECN Forum
Posted By: sparky IEEE article - 01/28/12 01:47 AM
http://www.combinationafci.com/resources/doc_ieee_combination_afci.pdf

an interesting IEEE artilce . from their latest workshop, via a Mr Joe Engle, phd

comments appreciated

~S~
Posted By: sparky Re: IEEE article - 01/30/12 01:31 PM
XXIII. CONCLUSIONS
The primary goal of this paper was to describe what a
Combination AFCI circuit breaker can do, while also clarifying
what it can’t do. The features of the Combination AFCI, and
the earlier Branch/feeder AFCI, are listed in Table 1. Neither
provides series arc protection, the Branch/feeder provides the
extra important feature of 30mA ground fault protection.
The paper goes on to explain, but not justify, how the
Combination AFCI came to be mandated, while the
Branch/feeder that provides more protection at less cost is
disallowed. The key drivers behind this were the AFCI
manufacturers, their NEMA organization, and UL. The author
hopes this paper will stir discussions amongst the principals
and correct any errors that were made concerning their
products’ performance. This would also include supporting
removing the Combination AFCI mandate from the NATIONAL
ELECTRICAL CODE (NFPA 70).
Finally, the author, having participating actively during the
AFCI development, would encourage the IEEE engineering
communities of these great institutions to become more
engaged to insure their codes and standards representatives
fully understand the technical issues. These are their
products; they have a responsibility to insure their products are
not inadvertently misrepresented.
Posted By: renosteinke Re: IEEE article - 01/30/12 08:46 PM
SO ... in a nutshell .... we have a former C-H person arguing that his product was better, yet the NEC mandates an inferior product?

We see a return to emphasis on the damaged appliance cord - and no mention of the legendary errant Romex staple?

We see another argument against AFCI devices?

We see an assertion that UL ignored their own study when they wrote the standard - and that the standard does not test for the primary feature claimed by the product? Sort of like not requiring a boat to float?

This paper might very well be the 'blue dress' of the AFCI debate.
Posted By: HotLine1 Re: IEEE article - 01/31/12 12:54 AM
I have to find the time to read this whole paper, and review again the videos that I have from Siemens, and others regarding the combo AFCI. I use these videos in my courses at the vo-tech, and now I wonder if the info is factual.

Thoughts, gentlemen??
Posted By: gfretwell Re: IEEE article - 01/31/12 06:08 AM
The most interesting thing to me is the "party line" votes in CMP-2 that just confirm what we have known all along. NFPA has become as corrupt as the government with the process being controlled by the corporations who will make money on the decisions.

It has never been a secret that these "combination" AFCIs were jammed into the code, long before they actually existed and the author contends they still don't.

I did not know they also dropped the requirement for the 30MA GF protection. I am guessing the CT interfered with the series arc detection. Evidently removing it still did not reach the desired result if you can believe the author.
Posted By: sparky Re: IEEE article - 01/31/12 12:34 PM
it's not the first blue dress Reno.....

http://www.mikeholt.com/mojonewsarchive/AFCI-HTML/HTML/AFCI_-_Why_I_Have_a_Problem_With_It~20020801.htm

http://www.mikeholt.com/mojonewsarchive/AFCI-HTML/HTML/AFCI_-_Important_Update_from_a_Certified_Fire_Investigator~20020812.htm

~S~
Posted By: sparky Re: IEEE article - 01/31/12 01:00 PM
Quote
The most interesting thing to me is the "party line" votes in CMP-2 that just confirm what we have known all along. NFPA has become as corrupt as the government with the process being controlled by the corporations who will make money on the decisions.


Quote
I have to find the time to read this whole paper, and review again the videos that I have from Siemens, and others regarding the combo AFCI. I use these videos in my courses at the vo-tech, and now I wonder if the info is factual.

Thoughts, gentlemen??


imho, a number of avenues exist fellas, one possibility is powers that be are legally confronted

another might simply be quiet nonconfrontational clerical changes predicated on a failure of bureacracy

yet another, occuring as we speak, is the focus on glowing contacts, i.e.-the entire afci market becomes moot

they may all occur simultaneously, i couldn't say....

in any case that has, or may occur , i would caution signing onto any manner of belief system

that belongs in church, not our trade, nor as a safety feature anywhere

just my electrical secularist opinion this a.m.
~S~
Posted By: renosteinke Re: IEEE article - 01/31/12 03:29 PM
I'll tell you where this is going .... right off my desk, and straight into City Hall. You bet the AHJ will have it brought to his attention - and I'll wager the AFCI requirements that were adopted when the adopted the 2011 NEC without modification get ammended out!

Look to similar rejections to become popular. All that talk about the 'expertise' behind the 'consensus based' NEC ... and it turns out they're no more upstanding than the Chicago City Council.

You have taken my code and made it into a den of thieves. Get out!
Posted By: HotLine1 Re: IEEE article - 01/31/12 07:49 PM
Now, I'm seriously contemplating revising some of my available video items that I use in my Vo-tech classes!

Posted By: sparky Re: IEEE article - 02/01/12 02:32 AM
I'm glad you folks care about the trade enough to digest this & get it out.

you really wouldn't believe how many folks i've talked to in the last ten years about the afci, lotta stories, lotta time spent, too many to list

and i've always been in the minority doing so.

maybe not so anymore....

~S~

Posted By: HotLine1 Re: IEEE article - 02/01/12 02:39 AM
~s~:
Three (3) on your side. Hopefully, some others will jump in here!!

How about it??

You may consider changing the thread title, IMHO IEEE may be scaring people away.
Posted By: KJay Re: IEEE article - 02/03/12 10:19 PM
So, now that several days have gone by since first reading this article and the bile finally has settled back down in my stomach, I feel I can again begin to speak about the subject of AFCIs.
I think a lot of us have always felt these devices were based primarily on BS and junk science, but now we can see that it is almost certainly so.
I’m really not one to embrace the litigation which seems so rampant in our society today, but in a case like this, you have to wonder if maybe a class action suit isn’t in order and if one could possibly be brought about by builders, homeowners and even electrical contractors that were cumulatively mandated to endure millions of dollars in additional costs to install and implement these supposedly improved devices, solely on obviously deceptive information and ineffective testing procedures outlined, provided and performed by the manufactures, UL and with possibly NFPA involvement, as the only credible evidence that they were effective and functioned as intended and more importantly, as claimed. Hitting these institutions and the specific individuals involved in the wallet may be the best and only way to keep future market manipulation, fraud, coercion, and associated abuses like this in check. It doesn’t really matter how badly the safety experts wanted these devices to work or even if they had the best of intentions, there simply should be repercussions for this type of misrepresentation.
Posted By: sparky Re: IEEE article - 02/04/12 02:47 AM
afci's are a billion $$$ industry KJay, they have elevated housing in my state by 1K each on average

That said, the powers that be back a few decades ago instituted something of a contest to eradicate electriacl fires

unfortuneatly, they chose to ignore much of what is being revealed as physics contradictory to specific nominal hosusehold electricty

all means to an end do not maintain a justfication in a profession that prides itself on crossin' T's & dottin I's

just imho, further, if you are so moved by Dr E's revelations, do e-mail them to the powers that be in your state

i have, with a hearty 'thank you' as well as pass on promise



~S~
Posted By: HotLine1 Re: IEEE article - 02/04/12 03:19 AM
OK, and Kjay makes four.

I posted my current opinion on this matter in the other thread (Pashchens Law).

Reading thru these two threads has really been a learning experience for me.

Where is everybody else on this matter??

George?? Harold?? SparkyinAK?? Scott35?? Electure?? Anyone??
Posted By: Trumpy Re: IEEE article - 02/04/12 07:41 AM
John (Hotline),
Being an "out of towner" I can't really say a lot about the reasons behind the use of AFCI's, in fact I'd never heard of them until I signed up here, this could be because the US uses a low voltage/high current supply system in residential places, the line current is double what it would be here with a 230V supply system.

However, I will say this, if series arcing is a REAL problem over there, more emphasis needs to be put on the installation standard of wiring, if wires are in a position where they are stretched, kinked or what have you, you really need to look at not only installation practices, but those that are doing this work.

If the problem is because of poor utilisation by home-owners with damaged flexes and what not, I cannot see an extra device at the panel being of any REAL use, it will not change their behaviours.

John, a few years ago I was a Fire Safety Officer, charged with taking the message of good Fire Safety to the community.
9/10th's of my work unfortunately was explaining WHY a fire in their house had happened.

IMHO,
An AFCI is short sighted, what you need is good modern Circuit Breaker protection and a GFCI backing that up.
Anything less is poor design.
Posted By: sparky Re: IEEE article - 02/04/12 01:29 PM
Trumpy,

i suppose an objective stance such as yours views us as a less than perfect science

many of us would like to see this issue cleaned up as well, you yourself might be helpful on the other side of the globe

One revealing venture might be investigating what the rest of the world incorporates for ocpd protectants

for instance,one example might be the euro differentails that step into both hot AND nuetral buss manufactured resi panels

my point would be did these folks reinvent the wheel here?

and after we had the stones to promote the NEC to international status.....

~S~
Posted By: pdh Re: IEEE article - 02/04/12 04:33 PM
@Trumpy

The idea, as I understand it, isn't specifically to protect against all possible arc situations. Instead, it is to protect against a mid-range current fault that is not high enough to cause an instantaneous magnetic trip, but still needs to be interrupted because a thermal trip could manage to do so. It is called arc-fault because this mid range of current fault is based on a persistent arc that needs to be rapidly interrupted due to it's quick ability to start a fire (in seconds, as opposed to a hot wire which could take a few minutes). The physical action of an arc is also what puts it in this "no man's land" between magnetic and thermal trips where the usual trip curve is not acceptable for fire prevention.

One complication that prevents merely adjusting the trip curve is that some devices can briefly draw the same current levels briefly. Instantaneous magnetic trips are normally set high enough to avoid trips for these reasons. It comes down to there being two different cases of mid-range fault currents, one of which we do not want to trip on (motor starts, for example), and one which we do (continuing arc faults).

The arc based mid-range fault currents are the issue of concern which AFCI devices are proposed as the solution. This is a plausible solution because these devices are designed and/or intended to discriminate between the two kinds of mid-range current levels where we want to interrupt in some cases and not in others.

So the next question is, can "better design" and "modern circuit breakers" and/or GFCI be a suitable alternative solution?

I do suggest that AFCI devices actually are "modern circuit breakers".

I do NOT see how GFCI offers the ability to interrupt this kind of issue. That is not saying that GFCI is bad. There are other issues where GFCI offers a suitable solution. I just don't see how it can be a solution in this case.

That leaves "better design". This is more complicated to consider because it is not clearly defined what is a better design. For this "better design" to prevent these undesirable mid-range currents that involve an arc, it would have to be a means to suitably prevent these arcs at a sufficient statistical rate to be a worthy alternative.

There are numerous places where these arcs can occur. This includes both building wiring (in the scope of electrical codes and electrical contractor or electrician work), but also includes utilization equipment, and (often raised), the cords in cord and plug connections.

Good design I think would include removing risks from areas where arcs might, even in extreme circumstances, occur. A loose connection to a switch or outlet, or just a junction, is one of these cases. But required practice already deals with this be requiring these to be in suitably rated and listed fireproof boxes, with cables required to not be able to propagate any fires that might be started inside the boxes.

But this is about more than just loose connections.

The greatest risk appears to be outside the building wiring. NEC has limited scope, if any, for this. It is more of a product safety issue. With a massive base of existing unsafe product in place, solving this would be an overwhelming undertaking. Remember, the USA is a country where a major part (if not majority) of the population prefers trust on a private business instead of the government (not something I personally agree with, but still a reality that cannot be taken lightly here). This is in contrast with other countries, such as a lot of Europe, where the trust works other ways (more trust in government rather that private business), at least for lots of the people. Is NZ like that?

Does NZ have a program to go to everyone's home to remove the old unsafe wiring appliance cord wiring with something that is safer (perhaps more hardened against the kinds of damage that can create these arc situations)? Or has its product safety requirements mandated this for a sufficiently long period of time (decades) that unsafe appliance wiring is statically non-existent down under?

I just wonder if AFCI devices will, or will not, really make homes using them as safe, or safer than, homes in NZ (and other places that might not be adopting the use of AFCI). Or could it be that AHJ in these places are just waiting for some hard statistics to emerge regarding the safety (or lack thereof) before deciding whether promote AFCI devices or not?
© ECN Electrical Forums