AFCI troubleshooting suggestions

[goldstar]

One of my customers recently moved into a completely renovated house. New Sq D 200A MB panel was installed with AFCI breakers for all required circuits. He had gone on vacation for a week and during that time there was a rain storm (maybe lightening and maybe a brief power outage as well but not sure). When he returned one of the AFCI circuits started tripping when he turned on the office lights. On that circuit was the front entry-way lighting, bathroom and office area lighting and office receptacles. I'm sure it's an AFCI problem because I temporarily replaced the AFCI breaker with a std breaker and all worked fine. The only things that trip the AFCI are the fan/light unit in the bathroom and the office recessed lights.

The breaker panel was done in a workmanlike manner and very neat (but no inspection sticker on the panel - that makes me somewhat suspicious). Irrespective of that, I made an assumption (and that usually gets me into some trouble) that the branch circuit wiring must have been done in the same workmanlike manner and that the fan and lighting circuits were wired properly. With that, I can only guess that staples must have been driven too hard on those NM cables and they finally broke down. If anyone has any suggestions on other possibilities I would appreciate hearing them. Thanks in advance.

 

[ptonsparky]

First, check the fault codes the breakers are showing. They should indicate what is causing the trip.
and/or Insert a GFCI breaker vs a std breaker.

 

[Fred B]

Lightning surge even power restoration surge can leed to AFCI issues, thus the new requirement of a whole house surge protection. Try replacing or simply swap two of the AFCI breakers and see if the breaker holds on the suspect circuit or trips on the swapped circuit the breaker may be damaged. Also seen lightning and power surge damage a LED can light.

 

[James L]

I'm wondering what type of recessed lights.
Can lights with retrofit trims? If so, I would take a box of incandescent as well as a box of dimmable LED A19 bulbs.

If it's only a few lights, you might get somewhere by starting with lamp swaps.

 

[ActionDave]

..... With that, I can only guess that staples must have been driven too hard on those NM cables and they finally broke down. If anyone has any suggestions on other possibilities I would appreciate hearing them. Thanks in advance.

I wouldn't assume anything wrong with the wire or the staples. It is a known fact, confessed to by the manufacturers that AFCIs nuisance trip. I had a dual function AFCI tripping for no reason other than we bought a new fridge about a year ago.

If you want to rule out any problems with the wiring don't swap out with a regular breaker, put in a GFCI breaker. If that holds then you are down to replacing breakers with a newer model, moving breakers to other positions in the panel.

 

[ramsy]

With that, I can only guess that staples must have been driven too hard on those NM cables and they finally broke down.

If AFCI outlet I suspect wiring issues, but with less impedance protection AFCI breakers are always subject to failure.

If it makes you feel better, a 100.v insulation test will find issues continuity testers can't, without smoking devices & appliances.

 

[Jpflex]

One of my customers recently moved into a completely renovated house. New Sq D 200A MB panel was installed with AFCI breakers for all required circuits. He had gone on vacation for a week and during that time there was a rain storm (maybe lightening and maybe a brief power outage as well but not sure). When he returned one of the AFCI circuits started tripping when he turned on the office lights. On that circuit was the front entry-way lighting, bathroom and office area lighting and office receptacles. I'm sure it's an AFCI problem because I temporarily replaced the AFCI breaker with a std breaker and all worked fine. The only things that trip the AFCI are the fan/light unit in the bathroom and the office recessed lights.

The breaker panel was done in a workmanlike manner and very neat (but no inspection sticker on the panel - that makes me somewhat suspicious). Irrespective of that, I made an assumption (and that usually gets me into some trouble) that the branch circuit wiring must have been done in the same workmanlike manner and that the fan and lighting circuits were wired properly. With that, I can only guess that staples must have been driven too hard on those NM cables and they finally broke down. If anyone has any suggestions on other possibilities I would appreciate hearing them. Thanks in advance.

The company I work for doesn’t like to spend money on what is required by code. Therefore on the last two houses I had to use NEC code alternate option by placing an AFCI receptacle at the start of each circuit with standard breakers in a dwelling ( hope this meets code as its writing can be ambiguous)

In relation to this I hear a lot of new problems resulting from these new gfci AFCI requirements especially for electric cars using charge stations and invalid trips

 

[ActionDave]

The company I work for doesn’t like to spend money on what is required by code. Therefore on the last two houses I had to use NEC code alternate option by placing an AFCI receptacle at the start of each circuit with standard breakers in a dwelling ( hope this meets code as its writing can be ambiguous)

The writing is not ambiguous it's specific.

A listed branch-circuit-type arc-fault circuit interrupter installed at the first outlet on the branch circuit in combination with a listed branch-circuit overcurrent protective device where all of the following conditions are met:

1. The wiring shall be continuous from the branch-circuit device to the arc-fault circuit interrupter.
2. The maximum length of the branch-circuit wiring from the 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 12 AWG conductor.
3. The first box in the shall be marked to indicate that it is the first of the circuit.
4. The combination of the device and branch-circuit AFCI shall be identified as meeting the requirements for a system combination-type AFCI and shall be listed as such.

Particular attention should be paid to the word Listed which has a specific definition in art. 100

Listed. Equipment, materials, or services included in a list published by an organization that is acceptable to the authority having jurisdiction and concerned with evaluation of products or services, that maintains periodic inspection of production of listed equipment or materials or periodic evaluation of services, and whose listing states that either the equipment, material, or service meets appropriate designated standards or has been tested and found suitable for a specified purpose.

Given that you interpret such detailed language as ambiguous it's likely you are not meeting code.

 

[goldstar]

Lightning surge even power restoration surge can leed to AFCI issues, thus the new requirement of a whole house surge protection. Try replacing or simply swap two of the AFCI breakers and see if the breaker holds on the suspect circuit or trips on the swapped circuit the breaker may be damaged. Also seen lightning and power surge damage a LED can light.

I tried swapping with another AFCI breaker in that panel and the breaker trips immediately (as did the original one). That's what leads me to believe it's a "staple in the wire" issue. Every other light and receptacle on that circuit work fine. On my next trip back I'm going to try first removing the fan/light from its housing to see if I still have the problem. If that doesn't work I'm going to try to unsplice the wires inside the fan enclosure. If it still trips then I'm thinking it has to be a staple issue. There's only about 10' of wire from the switch JB to the fan.

 

[ActionDave]

It has to be a staple. What else could it be? Whoever heard of an AFCI tripping for reasons that have nothing to do with the wiring in the house?

 

[mtnelect]

One of my customers recently moved into a completely renovated house. New Sq D 200A MB panel was installed with AFCI breakers for all required circuits. He had gone on vacation for a week and during that time there was a rain storm (maybe lightening and maybe a brief power outage as well but not sure). When he returned one of the AFCI circuits started tripping when he turned on the office lights. On that circuit was the front entry-way lighting, bathroom and office area lighting and office receptacles. I'm sure it's an AFCI problem because I temporarily replaced the AFCI breaker with a std breaker and all worked fine. The only things that trip the AFCI are the fan/light unit in the bathroom and the office recessed lights.

The breaker panel was done in a workmanlike manner and very neat (but no inspection sticker on the panel - that makes me somewhat suspicious). Irrespective of that, I made an assumption (and that usually gets me into some trouble) that the branch circuit wiring must have been done in the same workmanlike manner and that the fan and lighting circuits were wired properly. With that, I can only guess that staples must have been driven too hard on those NM cables and they finally broke down. If anyone has any suggestions on other possibilities I would appreciate hearing them. Thanks in advance.

Please let me know if this is your problem, would love the documentation.

 

[growler]

I tried swapping with another AFCI breaker in that panel and the breaker trips immediately (as did the original one).

When an AFCI breaker trips immediately I normally think of a ground fault. Or a bad breaker and you have already switched that out.

I would do extactly what you are going to do and disconnect different parts of the circuit until you find the fault.
The only thing I would watch out for is there may be more connected to the circuit than you know about. I have had exterior receptacles and attic lights get wet during a rain storm and develope a ground fault.

 

[Jpflex]

The writing is not ambiguous it's specific.



Particular attention should be paid to the word Listed which has a specific definition in art. 100



Given that you interpret such detailed language as ambiguous it's likely you are not meeting code.

There are a lot of wording in NEC that is ambiguous not absolute to one section. If you read the code regarding AFCI requirements and what I posted then you should of had no ambiguity to whether I am meeting code.

 

[letgomywago]

Is it a homeline or qo? If it's a homeline check with an eaton classified afci they all use their own programs sometimes you'll end up finding it was just a bath fan or something one brand didn't include in their afci ignore waveform list.

 

[ActionDave]

There are a lot of wording in NEC that is ambiguous not absolute to one section.

There are plenty of ambiguities in the NEC and too many times when you have to jump from section to section to get the whole picture, the scenario you cited is not one of them.

If you read the code regarding AFCI requirements and what I posted then you should of had no ambiguity to whether I am meeting code.

I have no doubt you are not. Thing is you are the one that said.....

hope this meets code as its writing can be ambiguous

 

[electrofelon]

There are a lot of wording in NEC that is ambiguous not absolute to one section. If you read the code regarding AFCI requirements and what I posted then you should of had no ambiguity to whether I am meeting code.

Which section of 210.12 were you using? Most of those options do not even exist as a product, the only one where you could use a regular circuit breaker with is the metal wiring methods, #5.

 

[macmikeman]

If it is an overhead service go out there with a ladder and shake the service drop around like how the wind can. If it trips the afci call the poco up to fix their issue. And don't forget to bill the customer premium time because even though they looked at you like it was your fault it simply wasn't and you had to go out of your way to correct the situation for them.

 

[Jpflex]

There are plenty of ambiguities in the NEC and too many times when you have to jump from section to section to get the whole picture, the scenario you cited is not one of them.

I have no doubt you are not. Thing is you are the one that said.....

Like I said before, the code says that as an alternate option, you can use an AFCI at first receptacle of a circuit if within 50 ft length of 14-2 or 70ft on 12-2 For a family dwelling. The code does not provide much more text on this nor answer further questions or examples, Such as providing diagrams such as they do in counter and wall receptacle spacing.

I have read the code but am paraphrasing to the best I can recall since I cannot get my 2020 NEC book out at the moment

 

[ramsy]

It has to be a staple. What else could it be? Whoever heard of an AFCI tripping for reasons that have nothing to do with the wiring in the house?

Neutral to ground resistance, hold them in opposite hands with switch turned off, trips AFCI every time.

 

[ActionDave]

Like I said before, the code says that as an alternate option, you can use an AFCI at first receptacle of a circuit if within 50 ft length of 14-2 or 70ft on 12-2 For a family dwelling. The code does not provide much more text on this

Yes it does.

nor answer further questions or examples,

Because there is no need to.

Such as providing diagrams such as they do in counter and wall receptacle spacing.

You got me there.