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Old 07-04-2010, 01:04 PM   #16
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Replacing circuit breakers with AFCI


In my case it is 'line to ground' arc which is not naturally occurring under any circumstances and doesn't get detected until AFCI is installed while can be be very hazardous and must be investigated IMO.

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Old 07-04-2010, 01:25 PM   #17
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Replacing circuit breakers with AFCI


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Originally Posted by ozdiy View Post
In my case it is 'line to ground' arc which is not naturally occurring under any circumstances and doesn't get detected until AFCI is installed while can be be very hazardous and must be investigated IMO.

it's a bit over my head but due to the fact that a neutral connected directly to the same point that the EGC is connect, I cannot understand how it can determine the difference between a L-N or L-G fault. As well when speaking of series arcs (which a light switch would be) there again, the load side of the switch is in fact connected, although through the load, to ground. But then again since I tend to see the requirement of AFCI breakers as the modern equivalent of the Salem witch trials, I just haven't gotten that deep into them.

anyway; sounds like it's time to get out the old ohmmeter, set it to megohms and turn off the main breaker. Remove all loads from the circuit and check for a highly resistive connection from the hot feed to ground. With all loads disconnected, you should have an absolute open (infinite resistance). Anything less is a leak.

then, check each of the loads connected to the circuit with the tripping breaker for line to ground leaks using the same range on the meter.
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Old 07-04-2010, 02:27 PM   #18
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Replacing circuit breakers with AFCI


It can sense the current through the L and N. If these currents are not the same it means that there is some L to G current occurring.

On top of that it can detect the voltage/current patterns (AC, alternating current) and can detect abnormal patterns like arcing. Unlike AC motor arcing, where the pattern would follow AC voltage, the harmful arcing would be random in nature, time and intensity.

Similarly it can detect the 'series arc'. It excludes those that are 5A or less (5A change from the baseline I would think. Also the duration and pattern of the arcing/current change must be taken into a consideration by AFCI).

I am sure there is a microprocessor in these units that does current/voltage analyses. This can be fairly complicated and we pay a premium for. Some stores quoted me $50 each + TAX for one (I have 10 of these in my panel!).

While there are many issues with AFCIs returned as a google search, I think some wiring issues or issues with appliances are undetected. Once AFCI is installed some of these issues come to "life".

There must be a good reason why AFCIs are now mandated. The best analogy I can find are airbags which where not mandatory and keep improving.

Last edited by ozdiy; 07-04-2010 at 02:31 PM.
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Old 07-04-2010, 03:01 PM   #19
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Replacing circuit breakers with AFCI


Quote:
ozdiy;465207]It can sense the current through the L and N. If these currents are not the same it means that there is some L to G current occurring.
this is what a GFCI does. It has nothing to do with arc faults. We have had these for years and they are proven effective and dependable.

Quote:
On top of that it can detect the voltage/current patterns (AC, alternating current) and can detect abnormal patterns like arcing. Unlike AC motor arcing, where the pattern would follow AC voltage, the harmful arcing would be random in nature, time and intensity
.apparently you haven't seen a motor with poorly contacting brushes before. The arcing is continual and non-coherent. It is simply there but since it is withing the design parameters of the AFCI I am expected to simply accept the nuisance tripping. Ok.

Quote:
Similarly it can detect the 'series arc'. It excludes those that are 5A or less (5A change from the baseline I would think. Also the duration and pattern of the arcing/current change must be taken into a consideration by AFCI).
5A? Dang, that is plenty to kill a person but here is a problem: when you flip a switch (that is rated for 20 amps and as such, could have up to a 20 amp load on it) there is a 20 amp draw, which is totally expected, normal, and acceptable. Then there is always the possibility of "bounce" with the contacts so the arc is continued or restarted. So, you are saying anytime I load a circuit over 5 amps I should simply acccept the AFCI breaker might trip but that is ok because that is within the design parameters?

Quote:
I am sure there is a microprocessor in these units that does current/voltage analyses. This can be fairly complicated and we pay a premium for. Some stores quoted me $50 each + TAX for one (I have 10 of these in my panel!).
and of course, since the life expectancy of a breaker is accepted as decades, I suppose we can expect the same of these as well. Sure.

and then, how do you determine it is actually a fault and not a defective breaker? There is no means to do so.

Quote:
While there are many issues with AFCIs returned as a google search, I think some wiring issues or issues with appliances are undetected. Once AFCI is installed some of these issues come to "life".
I don't disagree but the fact is: AFCI's are still very problematic, even when there is no true problem. They are still too early in their design to mandate them. It is simply a gold mine for the manufacturers at this point with no method of avoiding it.




Quote:
There must be a good reason why AFCIs are now mandated. The best analogy
I can tell you for a fact the inclusion of AFCI's were manufacturer driven. When AFCI's were first included in the code, you could not actually buy an AFCI breaker. Even when you eventually could, there was only one manufacturer of the devices. This is one of the reasons Michigan opted AFCI's out of the first code it was in; It was not possible to fulfill the requirements of the code.
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Old 07-04-2010, 05:29 PM   #20
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Replacing circuit breakers with AFCI


Let me react to each and every question of yours in the order:

1) GFCI and AFCI, both need to measure currents/voltage but they are not the same, they do not provide the same protection, and are not redundant.

http://www.sea.siemens.com/us/Produc...erentfromaGFCI

How is an AFCI different from a GFCI?
Although the AFCI and GFCI may look very similar, their purpose is quite different. AFCIs are designed to address the hazards that result from arcing, while GFCIs (Ground Fault Circuit Interrupters) are designed to address shock hazards and are intended for the protection of personnel.

2) I have seen plenty of brushed motors and arcs between the brushes and the commutator. The arcing pattern depends on the RPM, frequency of the AC current, number of winds and comutator plates. I do not design AFCI but I would bet the designers did consider all these to prevent tips. There is a pattern but you would have to use a high speed camera or a strobe light to see the pattern. You can't see it with a naked eye.

3) See 1), AFCI is not replacing GFCI, it is arc protection. Yes, 5A would kill a horse but the 5A parameter is chosen as a threshold for Siemens AFCI. And is chosen not to save lives from getting electrocuted. After all it is the 'series arc' protection. I do not believe that 5A is the absolute current but instead the current change from the normal operational current, after the device was turned on.

4) Yes, there are testing and troubleshooting procedures:
a) http://www.sea.siemens.com/us/Produc...stic_Tool.aspx
b) http://www.sea.siemens.com/us/Produc..._Features.aspx
c) http://www.thecircuitdetective.com/a...t_breakers.htm
and many more...


5) This gentleman seems to disagree with you there...
" I have not once been called on to deal with a repeatedly tripping AFCI. "
http://www.thecircuitdetective.com/a...t_breakers.htm

6) I can't tell who drove the new code. But from the many hours I spent researching I think it is a good idea to have AFCI, that is why I am replacing all mine with AFCI.
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Old 07-04-2010, 05:58 PM   #21
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Replacing circuit breakers with AFCI


Quote:
1) GFCI and AFCI, both need to measure currents/voltage but they are not the same, they do not provide the same protection, and are not redundant.

http://www.sea.siemens.com/us/Produc...erentfromaGFCI

How is an AFCI different from a GFCI?
Although the AFCI and GFCI may look very similar, their purpose is quite different. AFCIs are designed to address the hazards that result from arcing, while GFCIs (Ground Fault Circuit Interrupters) are designed to address shock hazards and are intended for the protection of personnel.
you explained the means a GFCI uses to protect a circuit. If in fact an AFCI uses that same means, it is then not an AFCI but a GFCI. I understand your explanation to be incorrect.

Quote:
2) I have seen plenty of brushed motors and arcs between the brushes and the commutator. The arcing pattern depends on the RPM, frequency of the AC current, number of winds and comutator plates. I do not design AFCI but I would bet the designers did consider all these to prevent tips. There is a pattern but you would have to use a high speed camera or a strobe light to see the pattern. You can't see it with a naked eye.
there is much more to it than that. If the commutator is not perfectly round or there are ridges or grooves on any segment perpendicular to the shaft, there could be a situation where there was an arc, then no arc, then again an arc on just one segment or vice versa. It would be impossible to consider such an action as it is totally at random. I have seem motors that looked like a 4th of July sparkler and I have seen motors that had as much arcing as a brushless motor. Arcs are random and can be totally out of sync with any realtionship of speed or even segment sections of the commutator.



Quote:
3) See 1), AFCI is not replacing GFCI, it is arc protection. Yes, 5A would kill a horse but the 5A parameter is chosen as a threshold for Siemens AFCI. And is chosen not to save lives from getting electrocuted. After all it is the 'series arc' protection. I do not believe that 5A is the absolute current but instead the current change from the normal operational current, after the device was turned on.
but when you turn a switch on, there is a full load draw from what would be perceived as the "normal" current.

4) Yes, there are testing and troubleshooting procedures:
attempts to diagnose the circuit, not the breaker
simply a tattle tale indicator but what it the breaker is makfunctioning? How do you know?
you need to bring the more. Bring something that allows you to determine if the breaker is actually bad. At $50 a pop, swap out to diagnose is not going to be a popular choice.

Quote:
5) This gentleman seems to disagree with you there...
" I have not once been called on to deal with a repeatedly tripping AFCI. "
http://www.thecircuitdetective.com/a...t_breakers.htm
You want the names of 10 electricians that hold opposing opinions? You list one guy that hasn;t seen problems. I know at least 1 electrician that has never seen a problem with a FP stablock panel. Does that mean there really isn't any problems with FP Stabloc panels?

On top of that, read this thread. Notice the claims of (paraphrased) "that brand of AFCI is reported to be problematic when placed next to other AFCI breakers" or "buy the highest patent number breaker you can find"

You don't think that speaks to reoccurring problems?

Quote:
6) I can't tell who drove the new code. But from the many hours I spent researching I think it is a good idea to have AFCI, that is why I am replacing all mine with AFCI.
You should be able to; I had just informed you who did and that is from people that are on code panels. When they put this in the code, you could not buy an AFCI breaker. When I went through code update class for that year, (which is well after it was actually proposed to be put in the code and printing and distribution of the new code book) we spoke in theoretical terms because we could not get our hands on an AFCI breaker or any manufacturers literature to try to understand the things.

It was a solution to a (questionable as to how often it was occurring) problem. The manufacturer said "hey guys, here is the solution to that problem (we can't document as to how often it actually is a problem). How about we put that in the code. It is sure to save somebody.

and viola`, here we are talking about problems with AFCI breakers.

The fact that you are claiming there are no problems with AFCI breakers within a thread speaking about problems with AFCI breakers is a bit ironic, don't ya think?

Don't get me wrong; I see the AFCI as a benefit in principle. The problem is; it is a lot like so many other things; we say it is mandatory, we build it, it has problems, we fight for years dealing with the problems that are from rushing the entire situation.
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Old 07-04-2010, 07:04 PM   #22
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Replacing circuit breakers with AFCI


http://forums.mikeholt.com/archive/i...p/t-97059.html
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Old 07-04-2010, 07:12 PM   #23
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Replacing circuit breakers with AFCI


a few excerpts from that thread:

Quote:
Yeesh!

It just occured to me how diabolical the manufacturer's web is.

Not only does the client purchase $$$ of AFCIs, and $$$ of trouble shooting labor is included somehow, but, also, the contractor is going to spend $$$$$$ on test equipment that will have to be replaced everytime the AFCI electronics and firmware evolve. And the contractor will also need to spend $$$$$$$$$ on data logging equipment in order to even blame the AFCI.

Boss Tweed: "Nothing personal, just buisiness." :roll:
Quote:
I recall a newsletter or something that when afci's were being considered, Mike Holt warned of all the problems and was not very supportive of afci's. One of his concerns was once property owners had enough headaches with afci's that they would just pull them and pop in a standard breaker anyway!
Quote:
Customer was hanging his dog tags on his vanity light, like the one pictured below, in the master bathroom. He would wake up in the morning to find he didn't have any power in the master bedroom and to the bathroom lights.

He would shower, get dressed, and put his dog tags on for the day. Then he would go down to the panel in the basement, find the AFCI breaker was tripped and reset it. He would come home at the end of the day, hang his dog tags on the vanity light again, and the process would repeat itself all over again.

The chain for the dog tags was making contact with the outer shell of the light bulb and the metal casing of the vanity light. He had no idea that hanging his dog tags on the vanity light was causing a problem.

If it weren't for the fact that he stayed home the day I came out to troubleshoot and didn't put on his dog tags I wouldn't have found the problem. I would never have supsected he was hanging his dog tags on the vanity light.

http://i95.photobucket.com/albums/l1...anityLight.jpg
but the guy in the link ozdiy provided hasn't had any problems. Nope, not a one.

My guess is he is a technical writer and not an electrician.
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Old 07-04-2010, 07:34 PM   #24
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Replacing circuit breakers with AFCI


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there is nothing false about the arc created when flipping a switch. It is the nature of the beast and depending on the load on the switch, it can be quite an arc. Supposedly the AFCI breakers are designed to be able to ignore such an arc but honestly, I just not convinced AFCI is ready for the real world.

Heck, if you plug in or remove the plug on an appliance that is drawing current, you will get an arc as well. Just like the lights, the bigger the current draw, the bigger the arc.

the problem with AFCI is: arcs are a known, common, and accepted situation in much of our systems. Teaching the breaker the difference between an arc from a light switch, or a brushed motor, a relay, or unplugging an appliance compared to an unwanted arc from a short circuit appears to be a real problem, still.
I fully agree with all of your comments, however, my definition of a false arc is a necessary real, but unwanted arc. Sorry for the confusion.
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Old 07-04-2010, 07:50 PM   #25
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Replacing circuit breakers with AFCI


OK, I see your points. I see the nightmare. How do the homeowners and contractors manage these issues since the code is mandatory for quite some time? Wow, I am happy to have old house where this code doesn't apply.
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Old 07-04-2010, 08:09 PM   #26
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Replacing circuit breakers with AFCI


charge the customer money that shouldn't have to be spent to troubleshoot the darn things.

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