The creep of the residential AFCI

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Electricians need to understand the functionality of afci technology

Not the manufacturers pitch

Not any CMP substantiation

Not any canned NRTL study

Not any nema members opinion

~RJ~
 
I suggest everyone who has 10 minutes to spare go to http://www.nfpa.org/codes-and-standards/document-information-pages?mode=code&code=70&tab=editions and submit a revision 210-12 Arc-fault protection. The 2017 revision now removes the specific areas where afcis are required and simply says ALL 15 and 20amp 120v outlets are to be afci protected. Maybe if there original intent was to detect frayed or damaged cords then we should get rid of circuit afci requirements and have manufacturers integrate afci tech into all new plug in equipment so that the equipment itself will trip. This way the line side of the circuit will not be affected only the affected equipment. I did not use that suggestion in my submittal but should have. Maybe if more of us submit revisions to get rid of these things, at least until the tech is perfected, they will take it more seriously. Im sure getting rid of afci's is a pipe dream because of the BIG MONEY involved, but if we don't at least try for change than all of our talk is just that.
 
I guess I'm the only one who doesn't have a problem with AFCI's :? Seriously, I haven't had any issues with them. They catch sloppy wiring, and other mistakes...:roll: My vacuum doesn't trip the Square D Homeline AFCI's i have at my house. Can someone give more specific details on the issues?
 
klineelectric said:
I suggest everyone who has 10 minutes to spare go to http://www.nfpa.org/codes-and-standards/document-information-pages?mode=code&code=70&tab=editions and submit a revision 210-12 Arc-fault protection. The 2017 revision now removes the specific areas where afcis are required and simply says ALL 15 and 20amp 120v outlets are to be afci protected. Maybe if there original intent was to detect frayed or damaged cords then we should get rid of circuit afci requirements and have manufacturers integrate afci tech into all new plug in equipment so that the equipment itself will trip. This way the line side of the circuit will not be affected only the affected equipment. I did not use that suggestion in my submittal but should have. Maybe if more of us submit revisions to get rid of these things, at least until the tech is perfected, they will take it more seriously. Im sure getting rid of afci's is a pipe dream because of the BIG MONEY involved, but if we don't at least try for change than all of our talk is just that.
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Im going to say this being key:

France used to be 110/200 volts and much like our system here in the US. Ditto for some other countries. In the 60s France went to 220/380 volts and implemented RCDs with low magnetic trip circuit breakers, both of which provide protection against parallel and series arcs and both of which are less likely to fail being electromechinical. In the 45 years since this technology was made mandatory to combat the hazards associated with doubling the voltage, no major decrease in fires has taken place. In fact countries that use 120 or 230 volts, have or do not have RCDs all experience similar rates of fire. Granted the US has higher statistics which can be attributed to wood framed buildings, however other countries having wood framed buildings (yet require RCDs & IEC installation methods) still experience similar fire statistics.

With that said arc faults (assuming they are a real problem to start with) or what ever other protection AFCIs claim to offer are not behind electrical fires. If anything this proves AFCIs (which are nothing more then a glorified GFCI) are bogus and will not reduce electrical fires in North America.

The original claimed intent of AFCIs was supposed to handle damaged cords, however if anything it was an excuse to slowly sneak AFCIs into the code with more bogus claims about how they would protect in wall wiring.

People do not know the extent to which they are being lied to or to what degree propaganda has been falsified which I think explains why so few speak up. If more people speak up it might not change the NFPA, but it can certainly get those in charge of law interested. More states amending 210.12 is more then possible.
 
grizwald said:
I guess I'm the only one who doesn't have a problem with AFCI's :? Seriously, I haven't had any issues with them. They catch sloppy wiring, and other mistakes...:roll: My vacuum doesn't trip the Square D Homeline AFCI's i have at my house. Can someone give more specific details on the issues?
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Thats 30/50ma GFP doing that, nothing that a 5ma GFCI of 30 ma EGFP breaker will not do. If the NEC really was that desperate to make our electrical systems safer and equal to the rest of the world all they had to do was extend GFCI requirements to general use 120 volt circuits at the branch circuit origin. This would have caught a slew of code violations without to much cost or random tripping.


The issue is that arc logic itself does absolutely nothing other then adding a price point to device manufactures. Even if the technology was reliable and mature to this day it has never been proven thousands of home fires are the result of arcing. In fact lab testing has shown 120 volts (170 peak volts) by itself can not hold a sustained arc. Whether or not most homes get doses of 15,000 volt surges has also to be proven:
 
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grizwald said:
I guess I'm the only one who doesn't have a problem with AFCI's :? Seriously, I haven't had any issues with them. They catch sloppy wiring, and other mistakes...:roll: My vacuum doesn't trip the Square D Homeline AFCI's i have at my house. Can someone give more specific details on the issues?
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I have had two occasions where power tools that had soft start circuitry would trip an AFCI every time, GE and Homeline breakers.

I have seen a vacuum cleaner trip them when plugged into an AFCI protected circuit but not trip a different AFCI protected circuit. Same house, the tv would trip the breaker. Then the home owner switched out their halogen lamps with LED's and that tripped 'em. I was able to cure that one by putting one halogen lamp back in.

They are garbage. Expensive, useless garbage. Even if they did not nuisance trip they would still be garbage because there is no evidence they do anything to prevent fires.
 
210.12(A)(3)b presents with values that hint at an afci's only viable function

these values are not arbitrary ....

b. The maximum length of the branch-circuit wiring
from the branch-circuit overcurrent device to the
first outlet shall not exceed 15.2 m (50 ft) for a
14 AWG conductor or 21.3 m (70 ft) for a ]2 AWG
conductor.
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~RJ~
 
romex jockey said:
210.12(A)(3)b presents with values that hint at an afci's only viable function

these values are not arbitrary ....



~RJ~
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I agree check out the ROPs:


Supplemental arc protection breaker:


The UL report states “breakers can be effective at mitigating arcing faults,
provided the available fault current can be guaranteed to exceed the magnetic
trip level of the circuit breaker by a factor of 1.25.”
​
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The function of UL489e (supplemental arc breaker):



(b)The branch circuit breaker shall be listed and marked as having an
instantaneous trip not exceeding 300 amperes.
​
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This proposal establishes a circuit breaker
listing and marking requirement for the magnetic trip level at or below 300A in
order to ensure the breaker will protect the circuit from a parallel arcing fault
when at least 500A of available fault current is present as required in the first
parameter.
​
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LAROCCA, R.: While we support the panel action, continued support is
dependent upon review of additional data that would confirm the availability of
sufficient short circuit current capability at the panel of a typical installation.
The arc fault protection of the branch circuit will be provided by a system
that includes an outlet branch circuit AFCI, a circuit breaker having a known
instantaneous trip current and a branch circuit of a limited length and resistance
to ensure that the fault current is sufficient to trip the breaker during a parallel
arcing fault at the installation point of the outlet branch circuit AFCI. The latest
UL Research Report takes into consideration the impact of the available current
at the panel on the acceptable length of the branch circuit home run to the first
outlet. Calculation shows that as the available current at the origin of the
branch circuit varies, so does the allowable length of the home run.
Additional study is needed to provide data regarding the current available at
the origin of the branch circuit in a typical installation. From this data, the
panel will be able to determine if modification of the panel action should be
considered at the ROC.
​
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The report focused on providing data on the performance of conventional
circuit breakers with respect to arc faults in the home run portion of the branch
circuit and identified the parameters that must be met and controlled for this to
happen.
As long as these parameters are controlled, it can be concluded that an outlet
branch circuit type arc-fault circuit interrupter could possibly be used in
conjunction with a low-magnetic type circuit breaker to protect the branch
circuit. The critical parameters summarized in the report include: a minimum
available fault current, a maximum magnetic trip level for the circuit breaker,
impedance of the conductor, the actual voltage and the length of the conductor.
This proposal is based on utilizing the parameters set forth by the UL Report
to revise 210.12 to permit using an outlet branch circuit arc-fault circuit
interrupter in conjunction with a low magnetic trip circuit breaker.
​
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(2) A listed outlet branch circuit type arc-fault circuit interrupter installed at
the first outlet on the branch circuit where all of the following conditions are
met:
(a) The branch circuit over current protection device shall be a listed circuit
breaker having an instantaneous trip not exceeding 300 amperes.
​
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(2) A listed outlet branch circuit type arc-fault circuit interrupter installed at the
first outlet on the branch circuit where all of the following conditions are met :
(a) The available fault current at the branch circuit overcurrent device shall not
be less than 500A and the ambient temperature shall not be less than 20°C
(68°F).
(b)The branch circuit breaker shall be listed and marked as having an
instantaneous trip not exceeding 300 amperes.
© The branch circuit wiring shall be continuous from the branch circuit
overcurrent device to the outlet branch circuit arc-fault circuit interrupter.
(d) The maximum length of the branch circuit wiring from the branch circuit
overcurrent device to the first outlet shall be determined using the following:
L = (0.4×Vrms) / (1.25×300×pL)
L is the maximum length of the “home run” in feet;
pL is the resistivity per unit foot of each conductor of the NM cable gauge
being used; and
Vrms is the actual supply voltage.
​
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Can be found here starting at page 70-129 (139 in the viewer):


https://www.nfpa.org...0-A2013-ROP.pdf




To me it seems as though low magnetic trip is capable of mitigating parallel arc faults and its a concept recognized by the CMPs.

The 50/70 foot limit seems to come from a worst possible case scenario of limited fault current (at the service) and the furthest point in the circuit in which a supplemental arc breaker can trip magnetically under such condition.
 
Echo's IEC standards....even CMP-2 gets this!

so an AFCI is essentially an Americanized RCD

Why not simply mandate toroidal coils of descending magnitude , and spare us all the faux arc marketing ?

~RJ~
 
romex jockey said:
Echo's IEC standards....even CMP-2 gets this!

so an AFCI is essentially an Americanized RCD

Why not simply mandate toroidal coils of descending magnitude , and spare us all the faux arc marketing ?

~RJ~
Click to expand...



Personally 15 and 20amp breakers with electro-mechanical GFP would have been the best option if we really wanted to go there (see pic).

But, in my eyes this is even more profound. What the CMP admits (UL really) is that low magnetic trip (and GFP in other reports) do the same as a branch feeder AFCI. Both GFP and low magnetic trip have been mandated for over 50 years outside North America. The key comes from one fact: since the mass implementation of these 2 concepts there has only been a slight reduction in electrical fires, if any at all. An example is Norway having wood framed homes yet despite some of the strictest electrical requirements on earth continues to have comparable fire rates. In other words arc fault technology has already been mandated and tested for decades in the real world with only marginal results. Who really believes arc fault technology will eliminate several thousand home fires a year in the US where the voltage is half (cant hold a sustained arc) to begin with?

This is the ultimate proof AFCIs will not do as claimed.
 
Also for those who have concerns against sub main RCDs just to give you an idea of a thermal magnetic breaker breaker with built in GFP:
 
romex jockey said:
my theory cup runneth over Mbrooke :)


~RJ~
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:lol: That what they hope you will never figure out. But imo anyone who sits down and studies this in detail will see a disconnect between manufacturer claims and the science supposed to back it up (or lack there of).
 
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