Arc Fault Breakers

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Apaps03

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Fair Lawn NJ
Hello Guys, I have a client that wants me to install all arch fault breakers in his home. This home was wired with old school BX, and paper romex. I told him code doesn't require you to do this, but he insists on doing so. I was always under the impression that when installing Arch Fault breakers or outlets on old existing circuits you get a lot of false trips.

Has anyone done anything like this. Do you advise against doing this? MONEY IS MONEY, but I feel like this could be a big problem for the client. Any suggestions.
 
Hello Guys, I have a client that wants me to install all arch fault breakers in his home. This home was wired with old school BX, and paper romex. I told him code doesn't require you to do this, but he insists on doing so. I was always under the impression that when installing Arch Fault breakers or outlets on old existing circuits you get a lot of false trips.

Has anyone done anything like this. Do you advise against doing this? MONEY IS MONEY, but I feel like this could be a big problem for the client. Any suggestions.

Go for it. As long as he has been warned. Make sure you aren't sharing neutrals, maybe try one circuit at a time instead of socking several hundred dollars into AFCIs all at once. Keep records and report back. We would like to hear the results.
 
Also beware and inform the owner that if you have tripping issues it very well may be because of items that do need attention, like neutral to ground faults, shared neutrals (that shouldn't be), crossovers between branch circuits...
 
Not condoning AFCIs, because I don't like them. Well I don't like how they are unproven and forced on us to use. But if the OP were to use the newer AFCI without the GFP, there would be no trips due to shared or crossed neutrals, or neutrals & grounds shorted together. Since that is the only reason the arc fault breakers trip when a ground and neutral is shorted or a shared neutral.
 
Not condoning AFCIs, because I don't like them. Well I don't like how they are unproven and forced on us to use. But if the OP were to use the newer AFCI without the GFP, there would be no trips due to shared or crossed neutrals, or neutrals & grounds shorted together. Since that is the only reason the arc fault breakers trip when a ground and neutral is shorted or a shared neutral.
But without the GFP the AFCI device would catch very few more faults than a standard thermal magnetic breaker would. The GFP does most of the work that the fancy arc fault detection circuit is said to do. I am not sure if the arc fault detection circuit does anything more than cause false trips from some types of household equipment.
 
But without the GFP the AFCI device would catch very few more faults than a standard thermal magnetic breaker would. The GFP does most of the work that the fancy arc fault detection circuit is said to do. I am not sure if the arc fault detection circuit does anything more than cause false trips from some types of household equipment.

That was my point!:happyyes:
I actually had written that we could do very well with just GFCI breakers as that's mostly what's tripping AFCIs anyway. But I took that out before I got on a rant!:rant:
 
Hello Guys, I have a client that wants me to install all arch fault breakers in his home. This home was wired with old school BX, and paper romex. I told him code doesn't require you to do this, but he insists on doing so. I was always under the impression that when installing Arch Fault breakers or outlets on old existing circuits you get a lot of false trips.

Has anyone done anything like this. Do you advise against doing this? MONEY IS MONEY, but I feel like this could be a big problem for the client. Any suggestions.

Your client has been drinking the kool-aid. The truth is the truth even if no one believes it, a lie is a lie even if everyone believes it. :rant:


Nothing requires it but a full house of AFCIs could be nothing but headaches. AFCIs nuisance trip on all installs new and old. Some can detect crossed or grounded neutrals which is good thing, but they have a long history even new ones of tripping on televisions, treadmills vacuums ect. You should do as your client requests so, but warn him of the potential problems prior.
 
That was my point!:happyyes:
I actually had written that we could do very well with just GFCI breakers as that's mostly what's tripping AFCIs anyway. But I took that out before I got on a rant!:rant:

If they required 30ma protection on all circuits except critical ones like the fridge and furnace I would have no issue nor would we. Europe and other IEC countries have gfp (usually 30ma) protection on general use circuits and so far they only trip during an actual fault. No ones complaining. However the AFCI is what nuisance tripping on everything. switchgear and MV breakers/reclosers that do use arc fault logic dont do it with simple logic circuits like AFCI breakers. They do it via micro processor wave form analysis. Only that can accurately discriminate between variacs switching motors running and an actual arcing condition.
 
AFCI breakers do use microprocessor based waveform analysis (signature analysis). They just use really small and limited processors.
I think a larger problem is that nobody has particularly good data on what likely fault waveforms look like at LV, and LV sees an enormous variety of directly connected loads while MV more commonly drives transformers and occasional motors.
Can your sophisticated MV units detect arc faults on the secondary of an MV-->LV transformer?



Tapatalk!
 
AFCI breakers do use microprocessor based waveform analysis (signature analysis). They just use really small and limited processors.
I think a larger problem is that nobody has particularly good data on what likely fault waveforms look like at LV, and LV sees an enormous variety of directly connected loads while MV more commonly drives transformers and occasional motors.
Can your sophisticated MV units detect arc faults on the secondary of an MV-->LV transformer?



Tapatalk!

Signature analysis on AFCIs is nothing compared to the logic used in real AFCIs. Im talking about layers of equation based logic plus much higher data sampling rates. Very different concept light years ahead. More expensive and power consuming you bet, but its far more accurate. Some can even tall you how far down the line the fault is:p

"They just use really small and limited processors.", which is their issue.

MV sees the most complex faults. We are talking about 3 phase circuits with many different senerios where its often very difficult to employ GFP logic so arc fault analysis is key. Plus the need to differentiate different type of faults as well as those being imposed from neighboring feeders. When these units are designed and employed the goal isnt to detect faults on the secondary side. If protection is needed its done separately.
 
But without the GFP the AFCI device would catch very few more faults than a standard thermal magnetic breaker would. The GFP does most of the work that the fancy arc fault detection circuit is said to do. I am not sure if the arc fault detection circuit does anything more than cause false trips from some types of household equipment.

@ Don

With all due respect I would ask that you supply information that proves this hypothesis in detail and trust me Don; I am not being a wise-A88 when I say this. The GFP provides a needed function and assists in a glowing arc condition more than the standard AFCI circuitry which is looking for a characteristic during the waveform half-cycles of the various arcing pattern would but those conditions are only a sampling of given issues. Of the major producers of GFCI products, one major maker no longer includes GFP in their circuit breakers and they still pass all compliance tests in UL1699. The adding of GFP by some manufacturers is to simply pass the end line cotton test (UL1699) more effectively but it is not the only way to achieve this product compliance.

I do believe GFP in all circuit breakers and Branch receptacle type AFCI's bring an added bonus over standard OCPD's but we have to understand the service they provide and the intent of the product. Those "very few more faults" just may be what saves a home and occupant. The problem is we can't quantify this in numbers but we do see a decrease In home fires since the advent of AFCI devices (as stated in the 2012 NFPA Publication on House Fires). Remember that Smoke Alarms just warn us...AFCI's can potentially protect us and our homes when installed....only when installed.

Now I will agree in some rare cases ( and they are rare but all things rare become fuel for a fight) we see issues with AFCI Devices but considering the millions that are sold each year the percentages are so small that it is not a concern I hold high on my agenda of debate topics. It always amazes me that (not you, just saying) when electricians have a problem with an AFCI they choose to voice opposition to them without taking responsibility for letting those who can fix the problem know....why not visit www.afcisafety.org and post the nature of the problem, location of the problem, what has been done to try and resolve it and contact information on this website and it will help to resolve all of the problems in the future...its like the NEC, unless we get involved we really are just crying wolf to the problem.

Ok....I'm done with that rant......;)
 
I looked at the above link. Seems like they pretty well know what is causing the trips. They have a whole list to choose from.

What I liked best is the bit.. er ah... complaint phone #s listed at the bottom of the page. Hand them out to the homeowner so they can call each time with the pertinent information instead of my service call costing them $100+ a whack to do the same thing.
 
http://www.afcisafety.org/report.html

Just fill out this form....let the Manufacturers know what the problem is and what process caused it and give them a chance to make the product better. AFCI's are not going away but we all can play a role in making them better. Most people are too young to remember the "heartburn" over GFCI's back in the 60's so the debate has come full circle but I can tell you with 100% certainty the Manufacturers are listening. And I can tell you Dennis Alwon knows I speak to this from experience...enough said on that one.
 
@ Don

With all due respect I would ask that you supply information that proves this hypothesis in detail and trust me Don; I am not being a wise-A88 when I say this. The GFP provides a needed function and assists in a glowing arc condition more than the standard AFCI circuitry which is looking for a characteristic during the waveform half-cycles of the various arcing pattern would but those conditions are only a sampling of given issues. Of the major producers of GFCI products, one major maker no longer includes GFP in their circuit breakers and they still pass all compliance tests in UL1699. The adding of GFP by some manufacturers is to simply pass the end line cotton test (UL1699) more effectively but it is not the only way to achieve this product compliance.

I do believe GFP in all circuit breakers and Branch receptacle type AFCI's bring an added bonus over standard OCPD's but we have to understand the service they provide and the intent of the product. Those "very few more faults" just may be what saves a home and occupant. The problem is we can't quantify this in numbers but we do see a decrease In home fires since the advent of AFCI devices (as stated in the 2012 NFPA Publication on House Fires). Remember that Smoke Alarms just warn us...AFCI's can potentially protect us and our homes when installed....only when installed.

Now I will agree in some rare cases ( and they are rare but all things rare become fuel for a fight) we see issues with AFCI Devices but considering the millions that are sold each year the percentages are so small that it is not a concern I hold high on my agenda of debate topics. It always amazes me that (not you, just saying) when electricians have a problem with an AFCI they choose to voice opposition to them without taking responsibility for letting those who can fix the problem know....why not visit www.afcisafety.org and post the nature of the problem, location of the problem, what has been done to try and resolve it and contact information on this website and it will help to resolve all of the problems in the future...its like the NEC, unless we get involved we really are just crying wolf to the problem.

Ok....I'm done with that rant......;)
I find it hard to believe that AFCI's have been around long enough to be able to put together statistics that show they have prevented fires. They have only been in the NEC for a little over a decade so far, not all jurisdictions adopted codes containing AFCI requirements immediately after NFPA released them, some did amend the AFCI requirements, and there may be some that still do. Early requirements were just for bedrooms. Then factor in how many existing homes there are that don't have any AFCI's at all compared to how many new homes have been built that had any AFCI required to be installed. There are not that many AFCI's installed yet compared to how many non AFCI protected circuits are still out there. I think we will need at least 15 to 20 more years before we will have enough statistical data to be able to say whether or not AFCI's do what they are supposed to do. But also remember we do change other sections of code sometimes as well and those items can make some difference in how many fires there are also.
 
I would also be very happy to see statistics on how many of the AFCI trips that showed up bad wiring were actually arc fault rather than ground fault trips!

Tapatalk!
 
I would also be very happy to see statistics on how many of the AFCI trips that showed up bad wiring were actually arc fault rather than ground fault trips!

Tapatalk!

Me too. In the time we've been using them, starting in the bedrooms at least 10 yrs ago, I haven't had one AF tripping due to arcing. The problems have been either GF problems, or incompatibility with solid-state controls (dimmers) or ballasts.
 
Unless a glowing connection is taking place in a cable 30ma RCD detection wont do much. By the time its does we are talking fire. Nice try though.


30ma protection does the brunt of the work. It will certainly look better on UL tests because so many abnormal conditions will involve current leaking to ground.
 
Unless a glowing connection is taking place in a cable 30ma RCD detection wont do much. By the time its does we are talking fire. Nice try though.


30ma protection does the brunt of the work. It will certainly look better on UL tests because so many abnormal conditions will involve current leaking to ground.
And that protection is not intended for preventing fires (not directly). It may still reduce number of fires that incidentally happen because a fault to ground develops and trips it before it gets to a fire starting situation.

There have been tests posted here before where a glowing connection had no response from an AFCI. I myself am more concerned about a fire starting from a glowing connection then from any other "arcing event" that the AFCI may actually detect. Many of those other events will not be sustained by 120 volts long enough to be much threat. I have seen many more melt downs from 277 volts that were lucky they did not start a fire.
 
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