AFCI issue solved

[Sarge56]

I teach a high school shop class and am a part time electrician. This forum helped me in troubleshooting an AFCI problem. We wire a house for Habitat for Humanity each year. I got a call that the homeowner lost power to 2 bedrooms shortly after she moved in. Both are on the same circuit. I knew it was an AFCI issue because it kicked out when we were testing everything. The ceiling fan appeared to be the problem. But then it “went away”, meaning “see ya later”! I thought it might be caused by the really cheap fans. I researched this site and near the end of a thread I read something about the AFCI requiring a load to kick out and that the fault could be elsewhere. So I did not even check the fans. I went straight to the receptacles. 2nd one in I found a grounding wire resting against the grounded terminal. I checked all the others and no other problem. I reset the breaker and the problem was fixed. Thanks for that post. It saved a LOT of time and effort!

 

[ptonsparky]

Thanks for the feedback. It's nice to hear.

 

[Little Bill]

I don't know if it was my post that the OP saw but I had that problem a few years ago. I did the same and started with the receptacles, switches, and even the home run. Then realized the only thing left was a ceiling fan in the room. I only had to remove the canopy of the fan to see the problem. It was the EGC touching an exposed section of the neutral. The original installer had nicked the insulation on the neutral. My guess was that over the time period from original install, the vibration of the fan caused the movement of the conductors to result in the ground to neutral fault.
This problem would not be a problem today with some of the newer AFCIs not having a form of GFCI in them.

 

[tom baker]

An AFCI can trip on a neutral to ground connection, and the AFCI mfgs were slow to educate us
Thank you for you work with HfH.

 

[mopowr steve]

Most newer versions do not have ground fault component any more unless you get a Dual Function breaker.
So don’t get to excited yet.

 

[Sarge56]

The breaker would not hold before finding fault and holds after removing fault. Square D donates the breakers and load centers and I do not place the orders, so I do not know exactly what we are getting. We are still getting the older style AFCI with the pigtail. Why did the ground fault component get removed?

 

[ptonsparky]

The breaker would not hold before finding fault and holds after removing fault. Square D donates the breakers and load centers and I do not place the orders, so I do not know exactly what we are getting. We are still getting the older style AFCI with the pigtail. Why did the ground fault component get removed?

Those with more knowledge may chime in but I believe the GF was what was doing most of the 'detecting' in the earlier AFCIs. Why they removed it, when AFCIs 'worked' with it, IDK.

I personally prefer the Dual Function breakers now that on board diagnosis is built in.

 

[mopowr steve]

I was told that the original design used the same platform as the GFCI breakers already had with ct’s and much of the hardware already In the breaker, it was just a matter of adding another chip to handle the arc signatures. It just wasn’t sold/listed as having ground fault protection.
Then it seems that because of all the nuisance trips they opted to remove the ground fault component yet to just have the code making panel add all the GFCI requirements much of which are in areas requiring arc fault so we’re right back to where we were only now at the ~5ma threshold instead of what some claim was a 30ma threshold in the original afci design.