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    Question AFCIs Popping- Arc Faults or False Positives

    I recently rewired my house after a gut-to-the-studs fire and the new codes require a lot of AFCIs- basically, almost everywhere. I had one lighting circuit that kept popping- a new breaker resolved that. Now the breaker for the DW is popping. I've swapped it out and it's gotten better- less frequent- but it still happens. It's my impression that AFCI breakers aren't really ready for prime time- they throw a lot of false positives.

    The fire department and the insurance inspector say it was an electrical fire, caused by "something heavy on an extension cord," which has left me a bit sensitive about arc faults.

    So, my question is whether there's any way to detect a genuine arc fault, or conversely, show that a particular AFCI breaker is overly sensitive. Or that the problem is a combination of a sensitive AFCI and an electrically noisy DW. The AFCIs in question are Schneider QO from The Big Orange Box

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    Thumbs down Re: AFCIs Popping- Arc Faults or False Positives

    Caution: RANT

    I have been an electrician for a long time. When I was working full time I used to carry around boxes of twenty of so of each brand of AFCI. After careful testing of installed wiring that tripped the devices, I would swap out AFCIs until I found one that would work. This would frequently be one that had been removed from another location because it kept tripping there. In short (pun intended), some AFCI devices trip in circuits with no loads and are sensitive to things other than ARCing.

    In addition to sometimes tripping with no loads, some AFCIs are sensitive to things like certain switching power supplies (computers etc), motors with brushes (vacuum cleaners, power tools), and single phase motors with mechanical/electrical start switches, among others.

    A while back, ground fault devices (GFCI) hit the market and NEC pages and caught a bad rep because a lot of folks did sloppy wiring, and there were a few device issues. However the idea is really simple. You measure how much current enters the device on the hot leg and what goes back on the neutral (or other hot leg). If they are different by a specific measurable amount the device trips. Very simple circuit. Very reliable device. Almost zero callbacks

    The AFCI on the other hand uses an algorithm written by folks sitting at a desk to tell a smart chip what an arcing fault looks like when analyzed electronically. This snippet of code determines whether the spark from a switch turning on a lamp or heater is different from the small strands in a cord with the insulation rubbed off and "sort of" touching and sparking. Looking back, it would have been nice to have revision numbers and a data port to load the latest and greatest on each device so you'd know what problems you were up against from the get go and hopefully be able to mitigate them

    My personal opinion is that a device not ready for market was foisted off on the trade and trades folks were used as guinea pigs to test them. There has definitely been improvement, but I still have ACFIs to use for swapping when issues arise. The fact some work and some don't on the same unused circuits ought to tell people something as does the experiencing by end users who can't use certain new items with new wiring and requires multiple visits by a contractor to correct by swapping out what are supposed to be the same devices attempting to find one that will recognize a power supply when it "sees" it.

    My experience in residential wiring is that there are far more problems with bad connections (high resistance), both splicing wires and attaching to devices, than with arcing faults. YMMV

    All in all, as a licensed electrician and contractor I have to install AFCIs and do. I've also had to adjust rates to account for AFCI issues and definitely wouldn't install the current generation of stuff given the option. It can cost me upwards of$1000 to roll to make multiple change outs of a $25.00 AFCI to get one that will work. Are recently manufactured AFCIs better than those from years past? Yes. Are recently manufactured AFCIs a reliable and reasonably functioning device that can be expected to behave the same way on the same circuit? NO.

    I have heard that some electricians have left standard breakers with detailed instructions for changing out AFCIs in an obvious place for a completely frustrated homeowner to change out after multiple visits. They sure can't do it themselves legally, but can watch off the clock. And, uh, maybe help hold things.

    Again, my opinions and (many, many) observations. I'm not advocating anything that may be illegal or deemed unsafe. Just expect that there will most likely be problems and be prepared to fight with your suppliers to get everything running right.

    I probably shouldn't have written any of this but the coffee is taking its' time kicking in this morning

    Occam's eraser: The philosophical principle that even the simplest solution is bound to have something wrong with it.

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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Quote Originally Posted by Bill Kriegh View Post
    I have heard that some electricians have left standard breakers with detailed instructions for changing out AFCIs in an obvious place for a completely frustrated homeowner to change out after multiple visits. They sure can't do it themselves legally, but can watch off the clock. And, uh, maybe help hold things.
    Can they hold the screw driver while the homeowner turns it?

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
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    Default Re: AFCIs Popping- Arc Faults or False Positives

    @Bill,

    Occam's eraser... Gotta love it. I think it's a corollary of the thermodynamic reason Murphy's Law works- there are so many more ways for things to go wrong than right.

    Anyway, thanks for the rant, if for no other reason than it confirms some of my unbiased prejudices. The difference between Schroedinger's cat and his AFCI is that after you open the box, you know whether the cat survived. With his AFCI, you STILL don't know if you have a false positive or a genuine arc fault.



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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Quote Originally Posted by Bill Kriegh View Post
    I probably shouldn't have written any of this...
    I'm glad you did, well worth the read, and I appreciate your input.
    Thanks for sharing an honest opinion.

    Dom.


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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Occam's eraser: The philosophical principle that even the simplest solution is bound to have something wrong with it.

    Quote Originally Posted by BobboMax Fankhauser View Post
    @Bill,

    Occam's eraser... Gotta love it. I think it's a corollary of the thermodynamic reason Murphy's Law works- there are so many more ways for things to go wrong than right.
    A simple analogy is that Occam's eraser explains why there are so few true "yes" or "no" answers to questions - the reality is an answer which should actually be "Yes, but/and/if" or "no, but/and/if".

    Jerry Peck
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    Default Re: AFCIs Popping- Arc Faults or False Positives

    It is worth remembering that as a response to the fact that an AFCI cannot detect a series arc or a glowing connection even after it fails the manufacturers incorporated Ground Fault Protection of Equipment at the 30 milliampere trip level. When your finished wiring any Arc Fault Circuit Interrupter required circuit it should be tested with a Good Quality Multimeter as a minimum. Toward the end of my work in the craft I would test with a resistance tester set at 300 volts. Any detectable current flow to ground was a fail and we would find and clear the fault. Once we started insulation testing the built circuits the recalls went to zero. If you test a circuit with luminaires installed or loads plugged in There is a risk of damaging the load such as LED light transformers and plug in devices with electronic controls. I developed a prejudice that a lot of the high resistance ground faults were caused by electricians being pushed too hard for speed rather than balancing work rate with work quality.

    --
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    Default Re: AFCIs Popping- Arc Faults or False Positives

    I have tested circuits with a megger at 1 Kv that checked good and still tripped 7 or 8 AFCI devices, and the circuit worked perfectly when I installed the 9th one - which had been removed from a similar situation somewhere else.

    I quit doing tract houses a long time ago because the job reminds me of monkeys jumping around trying to get the production where the boss wants it. I occasionally use helpers on big resi jobs and they don't last very long if I see things showing up I don't like. So, yes, crappy work accounts for some of the issues with AFCIs and it's easy to come by. But not all of the issues are related to workmanship. A circuit that has been connected end to end and passed being tested with a megger should NOT be tripping an AFCI, either continuously or intermittently. It's absolute crap that a staple driven a bit too hard on a cable that still passes being megged will trip one of these things. There aren't any arcs doing the tripping. I've pulled cables, stripped them, and looked.

    I'd be much happier if the "wonder device" was able to detect glowing (or at least super hot) connections. I find evidence of these far more often than I should in old work and believe them to be much more of a problem.

    Occam's eraser: The philosophical principle that even the simplest solution is bound to have something wrong with it.

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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Quote Originally Posted by Bill Kriegh View Post
    I have tested circuits with a megger at 1 Kv that checked good and still tripped 7 or 8 AFCI devices, and the circuit worked perfectly when I installed the 9th one - which had been removed from a similar situation somewhere else.

    I quit doing tract houses a long time ago because the job reminds me of monkeys jumping around trying to get the production where the boss wants it. I occasionally use helpers on big resi jobs and they don't last very long if I see things showing up I don't like. So, yes, crappy work accounts for some of the issues with AFCIs and it's easy to come by. But not all of the issues are related to workmanship. A circuit that has been connected end to end and passed being tested with a megger should NOT be tripping an AFCI, either continuously or intermittently. It's absolute crap that a staple driven a bit too hard on a cable that still passes being megged will trip one of these things. There aren't any arcs doing the tripping. I've pulled cables, stripped them, and looked.

    I'd be much happier if the "wonder device" was able to detect glowing (or at least super hot) connections. I find evidence of these far more often than I should in old work and believe them to be much more of a problem.
    Well I cannot argue with field experience and all I can say about glowing connections and series arcs is AMEN.

    Early in the period when out county first adopted the AFCI requirement for most circuits instead of just bedrooms a tract of homes was built right in back of a friends home. He walked out on his back deck and keyed his portable radio which can only deliver 5 Watts of radio signal. The entirety of the new tract went dark. His tiny 5 watt radio signal tripped every one of the Cutler Hammer AFCIs in the new development. That is a well designed and carefully tested technology in that not sort of way. To their credit Cutler Hammer had a small army of electricians out there the following morning and changed out every AFCI for new ones with no questions asked. But I have to wonder who releases a product to market without first testing it for sensitivity to every day environmental stressors.

    --
    Tom Horne


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    Default Re: AFCIs Popping- Arc Faults or False Positives

    I used to be fairly anti AFCI because we would see so many with nuisance trips or ones that wouldn't trip at all when tested. That was probably 3-7 year ago range. Nowadays they seem to be better. I haven't gotten a call from a homeowner in a long time asking for a Sparky number because 'that breaker with the button on it doesn't work'.
    The Square D ones were really bad; the Siemens better. My complete guess is the manufacturers have tweaked the design.

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    Default Re: AFCIs Popping- Arc Faults or False Positives

    RANT WARNING

    I think AFCIs were a "pacification" device forced on the industry because of the number of "electrical fires". And, they were pushed to market rather quickly by the NEC requirement. My perception is that they worked by voodoo rather than well thought out engineering.

    I had second thoughts about the two page followup I wrote and cancelled the rant warning. Just suffice it to say that we feel obligated to protect our electronic gear with high dollar surge protectors and yet the industry wants us to believe that a smart chip device like an AFCI is going to be functioning after years hidden from view and none of the suggested testing ever being done. Okie dokie then.

    Occam's eraser: The philosophical principle that even the simplest solution is bound to have something wrong with it.

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    Default Re: AFCIs Popping- Arc Faults or False Positives

    An AFCI in an addition I built in 2017 located an error in one circuit. Two different Seimans breakers tripped when that circuit was used. I checked every outlet box and found no problem, crawled into an attic stuffed with insulation, required rating of R40 , and in a junction box, found one wire in a cluster had gotten pushed out of the wire nut. Bad connection that might not have surfaced until it caught fire. Just saying.

    John Kogel, RHI, BC HI Lic #47455
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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Quote Originally Posted by John Kogel View Post
    An AFCI in an addition I built in 2017 located an error in one circuit. Two different Seimans breakers tripped when that circuit was used. I checked every outlet box and found no problem, crawled into an attic stuffed with insulation, required rating of R40 , and in a junction box, found one wire in a cluster had gotten pushed out of the wire nut. Bad connection that might not have surfaced until it caught fire. Just saying.
    And that may have passed an insulation resistance/megger test.

    Without checking each and every connection, just passing an insulation resistance/megger test does not verify that all connections are properly made up and good.

    Jerry Peck
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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Morning, Bill. Hope to find you well and in good spirits today.


    As for, AFCI reliability and 'Nuisance' tripping or false posative tripping.
    Personally, I would not be that particularly bothered seeing what might have been avoided.
    But then again, it depends what you where doing at the time the false posative nuisance took place I suppose Hm?

    Look at it from my prospective. I inspect homes. I test GFCI and AFCI breakers. For AFCI OCPD's, both at the panel, as recommended by the manufacture and at downstream receptacles. Over 50% of the time the circuit is not labeled right and/or the AFCI is not operating properly.Now its a pain in the behind for me, but I want my clients to be safe and aware of electrical problems.

    In your case.
    I take it the circuit current draw was typical/usual, Bill? Sorry for using you double reference, Jerry. Your the king mate, in my books.


    Incompatible Electronic Devices and Nuisance tripping are occasional/casual/infrequent?
    I feel one should know what Incompatible Electronic Devices to use and how to rectify this.
    Tread mills, Televisions, Current pulse times are known to cause nuisance tripping.
    NEMA AFCI compatibility PDF.

    Thanks for the post.
    Keep well.
    Regards.
    Robert

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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Quote Originally Posted by THOMAS HORNE View Post
    It is worth remembering that as a response to the fact that an AFCI cannot detect a series arc or a glowing connection even after it fails the manufacturers incorporated Ground Fault Protection of Equipment at the 30 milliampere trip level. W
    --
    Tom Horne
    Tom, they're getting away from that now. If I understand correctly, the present generation of BR AFCIs don't incorporate any GF sensing, and the soon-to come generation of CH AFCIs are designed similarly.


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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Quote Originally Posted by Bill Kriegh View Post
    Caution: RANT

    I have been an electrician for a long time. When I was working full time I used to carry around boxes of twenty of so of each brand of AFCI. After careful testing of installed wiring that tripped the devices, I would swap out AFCIs until I found one that would work. This would frequently be one that had been removed from another location because it kept tripping there. In short (pun intended), some AFCI devices trip in circuits with no loads and are sensitive to things other than ARCing.

    In addition to sometimes tripping with no loads, some AFCIs are sensitive to things like certain switching power supplies (computers etc), motors with brushes (vacuum cleaners, power tools), and single phase motors with mechanical/electrical start switches, among others.

    A while back, ground fault devices (GFCI) hit the market and NEC pages and caught a bad rep because a lot of folks did sloppy wiring, and there were a few device issues. However the idea is really simple. You measure how much current enters the device on the hot leg and what goes back on the neutral (or other hot leg). If they are different by a specific measurable amount the device trips. Very simple circuit. Very reliable device. Almost zero callbacks

    The AFCI on the other hand uses an algorithm written by folks sitting at a desk to tell a smart chip what an arcing fault looks like when analyzed electronically. This snippet of code determines whether the spark from a switch turning on a lamp or heater is different from the small strands in a cord with the insulation rubbed off and "sort of" touching and sparking. Looking back, it would have been nice to have revision numbers and a data port to load the latest and greatest on each device so you'd know what problems you were up against from the get go and hopefully be able to mitigate them

    My personal opinion is that a device not ready for market was foisted off on the trade and trades folks were used as guinea pigs to test them. There has definitely been improvement, but I still have ACFIs to use for swapping when issues arise. The fact some work and some don't on the same unused circuits ought to tell people something as does the experiencing by end users who can't use certain new items with new wiring and requires multiple visits by a contractor to correct by swapping out what are supposed to be the same devices attempting to find one that will recognize a power supply when it "sees" it.

    My experience in residential wiring is that there are far more problems with bad connections (high resistance), both splicing wires and attaching to devices, than with arcing faults. YMMV

    All in all, as a licensed electrician and contractor I have to install AFCIs and do. I've also had to adjust rates to account for AFCI issues and definitely wouldn't install the current generation of stuff given the option. It can cost me upwards of$1000 to roll to make multiple change outs of a $25.00 AFCI to get one that will work. Are recently manufactured AFCIs better than those from years past? Yes. Are recently manufactured AFCIs a reliable and reasonably functioning device that can be expected to behave the same way on the same circuit? NO.

    I have heard that some electricians have left standard breakers with detailed instructions for changing out AFCIs in an obvious place for a completely frustrated homeowner to change out after multiple visits. They sure can't do it themselves legally, but can watch off the clock. And, uh, maybe help hold things.

    Again, my opinions and (many, many) observations. I'm not advocating anything that may be illegal or deemed unsafe. Just expect that there will most likely be problems and be prepared to fight with your suppliers to get everything running right.

    I probably shouldn't have written any of this but the coffee is taking its' time kicking in this morning
    I have had issues in some homes with bad connections, but never anything related to an "Arc Fault" did have a rental house burn down many moons ago was suspected of being caused by rats house was unattended for a couple months an older home and was asphalt wiring.
    I would actually like some specific location to have a reliable ARC Fault myself, but then not with current tech, and not on any critical circuit, fridge, deep freeze, medical, etc and I would swapped them back to standard breakers on my own home, I do believe in the use of GFCI, but I only use near/around water areas, again not fridge, other critical equipment. Some outdoor equipment that is hardwired I have dedicated GFCI breakers for.

    But the current ARC Fault technology is crap
    Electrician, not as a business anymore, electrical/electronics engineering degree, yeah even worse, Sigh :-(


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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Time for the OP to pipe up again.

    I spoke with a technician from a local company that deals almost exclusively in breakers, typically very large ones (1000A) but also has experience with smaller ones, including AFCIs He's in agreement with the rants that have been posted in response to my question- he's seen the same erratic behavior and said he doesn't have any AFCIs in his home & sleeps well. His company does have a lab test for AFCI breakers, but he doesn't know any way to test a circuit in the field (Megger style tests aside.)

    So, my plan is to crawl under the sink and verify the receptacle connections and pull the modesty panel on the DW to see if I can access the cord-to-appliance connections. If I don't find anything there, I'll replace the AFCI once more. If that doesn't help, I'll go to a standard breaker. FWIW, the second AFCI is popping less than the original one. That tells me the breakers vary in their diagnoses of arc faults, which they shouldn't.

    Thanks for all the replies- several heads are generally a better test of reality than one.


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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Quote Originally Posted by BobboMax Fankhauser View Post
    FWIW, the second AFCI is popping less than the original one. That tells me the breakers vary in their diagnoses of arc faults, which they shouldn't.
    Two nit-picks.

    Unless you replaced the second AFCI with the first, you haven't demonstrated that the reduced frequency of tripping is due to the different breaker as opposed to a change in the appliance's behavior.

    IMO there should be differences in the response of different electronic breakers as they evolve, with updated hardware or firmware. You might want to check whether the two breakers are from the same series or edition. If it's not evident from the numbers on them, the manufacturer's tech support people will tell you. Reps have told me they buy samples of new appliances as they come on the market, so they can tweak their AFCIs to handle the appliances' current signatures.

    Yes, there also may be manufacturing variability, but having one AFCI in my house that will trip in response to my Milwaukee drill (and to nothing else), while those I've tested of the other 33 don't, I'd put my money on the one having been manufactured with an earlier design.


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    Default Re: AFCIs Popping- Arc Faults or False Positives

    [QUOTE=david shapiro;285676]Two nit-picks.

    Ref "Unless you replaced the second AFCI with the first," valid point, but I already took the first one back to The Big Orange Box. However, I think it's doubtful the current signature of the DW evolved enough to make a difference, so I suspect sample variation, or as you suggest, possibly a version difference.

    Agreed, "there should be differences in the response of different electronic breakers as they evolve," but documenting those differences is going to be difficult, verging on impossible, for an individual homeowner, even a relatively sophisticated one. Out of curiosity, if I get another (or replace #2 with an ordinary breaker) I'll see if there's any info as to version.

    Ref your Milwaukee drill motor, gotta love it. To me, the level of response variability we see, whether due to version, manufacturing variability or device signatures, says the technology isn't ready for prime time. Since there's about a 10-1 difference in retail cost. I'm cynical enough to suspect the profit motive led the manufacturers to get them into the code without regard to actual viability in the field. Interestingly, AFCI receptacles are 1/2 to 2/3rds the cost of load center AFCI breakers.

    OTOH, sometimes field testing is the only to discover subtle problems- at one company that made individualized, relatively high-value products, we'd put "green slips" in the service records of slightly suspect serial numbers, noting that reported problems should be passed on to Engineering. Hopefully, we cut the owners some slack on warranties and we didn't get sued too often.


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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Quote Originally Posted by BobboMax Fankhauser View Post
    @Bill,

    Occam's eraser... Gotta love it. I think it's a corollary of the thermodynamic reason Murphy's Law works- there are so many more ways for things to go wrong than right..
    One of the nasty facts about your finely shredded Murphy is that a lot of the things you can sit down to dinner with a lot of things wrong, but the plumbing still delivers water and drains it later, the lights still work, and meanwhile there are all these hidden whupses that a book I like calls seeds of failure. . . how will they grow, when will they blow?


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    Default Re: AFCIs Popping- Arc Faults or False Positives

    [QUOTE=david shapiro;285724]

    Ref "seeds of failure," I remember one job where I dealt with first floor T1-11 siding and studs "dry-rotted" from the inside. I eventually concluded the problem started with the flashing over a second floor window replacement 10 years earlier.


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    Default Re: AFCIs Popping- Arc Faults or False Positives

    [QUOTE=BobboMax Fankhauser;285723]
    Quote Originally Posted by david shapiro View Post
    Two nit-picks.

    Ref "Unless you replaced the second AFCI with the first," valid point, but I already took the first one back to The Big Orange Box. However, I think it's doubtful the current signature of the DW evolved enough to make a difference, so I suspect sample variation, or as you suggest, possibly a version difference.

    Agreed, "there should be differences in the response of different electronic breakers as they evolve," but documenting those differences is going to be difficult, verging on impossible, for an individual homeowner, even a relatively sophisticated one. Out of curiosity, if I get another (or replace #2 with an ordinary breaker) I'll see if there's any info as to version.

    Ref your Milwaukee drill motor, gotta love it. To me, the level of response variability we see, whether due to version, manufacturing variability or device signatures, says the technology isn't ready for prime time. Since there's about a 10-1 difference in retail cost. I'm cynical enough to suspect the profit motive led the manufacturers to get them into the code without regard to actual viability in the field. Interestingly, AFCI receptacles are 1/2 to 2/3rds the cost of load center AFCI breakers.

    OTOH, sometimes field testing is the only to discover subtle problems- at one company that made individualized, relatively high-value products, we'd put "green slips" in the service records of slightly suspect serial numbers, noting that reported problems should be passed on to Engineering. Hopefully, we cut the owners some slack on warranties and we didn't get sued too often.
    A lot of sensible points there, Bobbo. First, the evolution of the current signature. I daresay you're right, but . . . I'd say one day I used my electrical lawnmower (the one that the AFCI didn't like) at the house with just GFCI protection, and it worked fine, and the next time I used it the control switch burst into flame. So as we both know, it happens in the direction of increased failure.

    I certainly have warned customers to get a particular edition of a product. For instance, on what I expect will have been my very last install as a contractor, I advised a customer to go to the extra trouble and expense to get smoke alarms listed to UL 217, 8th ed. (I often let customers buy the equipment, provided that it met my specs.) Not necessarily easy, true.

    What's ready for prime time is kind of hard to judge. Look at the study of standard electromechanical CBs Aronstein published last year (available on Inspectapedia). I can't think of a technical reason the two aberrant manufacturers didn't calibrate their CBs as reliably as say the CHs. (I have another issue with Eaton, but not their CB tripping curves.)

    As for manufacturers pushing product out there with the requirement, you're spot on that this gave them a much, much bigger test. I don't see it as equivalent to the Tuskegee untreated syphilis research, but even though I like and recommend AFCIs I see some cynicism there. Maybe this also relates to the way the NFPA Technical Session was packed by two CB manufacturers this year, and I don't think for humanitarian reasons.


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    Default Re: AFCIs Popping- Arc Faults or False Positives

    Not sure if mentioned anywhere else but just in case adding this info
    been involved a little in the ham radio community
    there was a report that some having issues with AFCI breakers popping anytime would transmit.
    Seems logical, have an electronics degree and RF experience, basically if under stand AFCI is actually trying to detect the higher frequency caused by arcing ?
    Google some found one article one manuf worked with some ham folks trying to improve their interference rejection, so hoping newer and improved AFCI will have better interference rejection.
    However good to know case run across sporadic trips, could be interference from many sources
    One video showed where if keyed to transmit on a handheld GRMS radio and all AFCI breakers in the panel tripped.
    So could be any source emitting high frequency emissions, brush type motors, as in power tools, etc
    Very close by transmitting, ham, cell towers, etc ?
    hopefully not as much an issue newer versions, however may still happen if enough other interference ?
    And wonder if a nearby arc fault of some type could get superimposed on another line with AFCI tripping its breaker ?

    For code requirements for others not much can do
    However for my own use, I know at least for any safety, smoke/fire alarms, fridge, freezers, medical equipment, garage door openers etc. other appliance needs not using AFCI.


  24. #24
    Join Date
    Mar 2014
    Location
    Oregon
    Posts
    6

    Default Re: AFCIs Popping- Arc Faults or False Positives

    For the record...

    I opened up the J-box and tightened the terminals, opened up the connection box in the DW and R&Red the wire nuts. That seemed to reduce the number of (hopefully) false positives, but didn't eliminate them. The incidence is VERY variable- sometimes 3 to complete one cycle, then none for 2-3 complete cycles.

    I'm OK w/ randomness in a poker deal, but not in a "safety" device.


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