# Bad QO Arc Fault breaker installation



## EJPHI (May 7, 2008)

My bad.:jester:

This morning the lights went out in the bathroom. My wife was ironing at the time using the same circuit. This is an older 1960's house so there is a lot of shared wiring. When I replaced the panel a couple of years ago, I noticed that the bathroom, living room and master bedroom were all on the same circuit.

The AHJ required arc fault breakers in the new panel for any bedroom circuits.

I looked at the panel and noticed that there were no tripped breakers. After removing the cover, I saw that the offending circuit had a burned neutral. My camera couldn't take a good picture of the panel wiring so I took the first shot after replacing the breaker.

The screw was not tightened on the neutral wire causing it to get hot over time. The circuit normally draws about 7A and the clothes iron added about 10A for a total of 17A. This was enough to cause a flakey contact.

I love QO but SQD made it very difficult to verify the position of the neutral wire because it is so close to the bottom of the panel. I will pay very close attention to the quality of this connection in the future.

On the bright side, I get to dissect the breaker since there is no way I would trust its further service. Subsequent pictures show the innards.

You can see the oxidation on the neutral terminal.

You can also see that there are 2 transformers, the white one is used by the GFI circuit to detect differential current. Note the fat white wire exiting the breaker to provide the neutral connection.

The second transformer is used to detect fast transient currents. Since this is a first-generation arc-fault, it only detects parallel faults. It would not have detected the arcing associated with the poor neutral connection.

Overall, I am ipressed with the build quality of this circuit breaker. Would love to see the innards of competing breakers.

EJPHI


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## nrp3 (Jan 24, 2009)

I swapped out a QO panel with burned buss this week for a new one. I put in arc faults in for the lighting, bedroom, liv rm etc. I had to wire them up first and then clip them in place. I find this true for GE as well.


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## macmikeman (Jan 23, 2007)

Anything , but anything beats those six inch long BR arc faults to install into a panel. Not only do they stretch over so far they bang into the ground bars or neutral bars, they also don't work for beans....... always trip for no reason other than a load is applied. I made several test outlets in short emt raceways below a panel to prove this fact for demonstration purposes. Plug in a random drill from any of the trades on the jobsites and within a half a minute the false trip happens. I really ought to make a video of this and put it on you tube but not sure of the legal ramifications of doing so....


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## nrp3 (Jan 24, 2009)

I've been lucky as a whole with arc faults, either I wired something wrong or its been problems with power tools. That I have seen too with the BR, couple of years ago though. Maybe their better.


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## Meadow (Jan 14, 2011)

I always wire the hot and nuet to the AFCI before putting it in the panel. Much easier. Have seen similar things with other breakers (terminal not seated correctly)

As with installation and nusiance tripping ive had the most luck with GE AFCIs. Never had a nusiance trip call with GE but many with earlier Homelines. Another thing I really like about GE's newer AFCIs is that they are compatible with multi wire branch circuits, a huge life saver where cost is a concern (which is usually everywhere now with the economy).

Proof for skeptics:


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## EJPHI (May 7, 2008)

The installation instructions for the QO Arc-faults say to install the wires, then clip breaker into panel, and then torque the wire terminals. 

Siemens has the Q215AFC and Q220AFC two pole combination Arc-faults.

Some day Square D with get moving and provide these.


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## Shockdoc (Mar 4, 2010)

Wow, now is that considered an arc ??? What a waste of $40.


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## EJPHI (May 7, 2008)

Shockdoc said:


> Wow, now is that considered an arc ??? What a waste of $40.


Yeah I hear ya Shockdoc.

When I see discolored terminals, I assume the piece is defective. 

I always wanted to take one of these apart anyway. According to my wife, I got at least $12 of fun out of it; so I am only $28 in the hole.

EJPHI


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