Arc Fault Circuit Interrupter - Power cutting in/out?

[Imp]

Anyone have experience with one of these pieces of shit?

Mr. Google says that these things only came into being in the past decade or so, and development was rushed, they trip randomly all the time. Long story short, we rewired the entire house in the past few years, and one bedroom circuit is acting up.

A TV, cable box, DVD player, and alarm clock are the only things plugged into this circuit. They've been working with the AFCI for 2 or 3 years. It's only caused trouble once or twice when I used the outlet for a 12 amp vacuum cleaner (big no no with AFCIs and motorized devices).

Now, the circuit is flipping on and off -- by this, I mean the power cuts in and out as we can see the alarm clock flipping, the TV (CRT) cutting in/out, the cable box LED flipping. However, the circuit at the breaker box doesn't flip. There are periods for minutes at a time when it doesn't flip.

We've replaced the AFCI unit (there are 2 in the self-contained box, only 1 is acting up) once with a brand new one ($90... effing Canada), but it's still doing the same thing.

So, if it's not the AFCI, any clues as to what it is? Anyone with experience?

Reminder that it's not the AFCI switch at the breaker box flipping, just power cutting in and out on that circuit. Is there a real wiring fault that's confusing the AFCI?

Trying NOT to call an electrician, but will if all else fails.

Thanks, yo!

 

[Red Squirrel]

I heard nothing but bad stories about those, too. I can't say I've heard of them cutting in and out, only nuisance tripping. I suppose it could be plausible that it's on the verge of tripping but does not trip, but the "switch" moves enough to cause flickering then the fact that the power cuts out temporarily makes it retract back to on position internally. Just a theory though. I'd definitely replace it with a normal one just to rule it out.

If that circuit was not on an AFCI for a long time and there was never issues I'd just keep it on a regular one. Do you have any motorized devices at all on that circuit? Like even some of those air wick plug-ins have a tiny little fan inside. Could be something silly like that.

Not sure what the code is here for those but I know NEC says they have to be in every place that does not require a GFCI. Personally when I change my panel, I'm probably not going to bother. Current panel is a stab lok. It does not get any more unsafe than that and my house has not burned down since it was built in 1965. 😛

 

[phucheneh]

What kinda cable have you got? If it's U-verse or someone else that uses power line transmission, perhaps that could be causing issues?

...just a random shot in the dark. I have no idea what an AFCI even is, TBQH. 😀 [edit: looking at Wikipedia...the description sounds like 'thing that would've saved a bunch of appliances in my house from killing themselves due to erratic power delivery]

Why do high current AC motors cause issues?

 

[Imp]

The electricians didn't put one in until the inspector came and said it was required for bedrooms. I've heard of the code expanding to require practically every "outlet" -- by "outlet", they mean every connection including lights.

Nothing sparky or motorized. Just one TV, one cable box, one DVD player, and one alarm clock.

It's "illegal" to switch it to a normal breaker. Electricians won't risk their licenses, but Mr. Google says a lot of people do it anyways.

*Sigh*

The really pisser is that AFCIs sell for $35 in the US and for some reason they start at $80 in Canada (Home Depot websites). I'm used to being bent over in Canada, but a multiple of two? What. The. F*ck.

 

[Imp]

What kinda cable have you got? If it's U-verse or someone else that uses power line transmission, perhaps that could be causing issues?

...just a random shot in the dark. I have no idea what an AFCI even is, TBQH. 😀 [edit: looking at Wikipedia...the description sounds like 'thing that would've saved a bunch of appliances in my house from killing themselves due to erratic power delivery]

Why do high current AC motors cause issues?

It's cable TV from the cable company with a line drop, no idea what different types there are. The cable has been plugged in since the change to the new panel years ago though.

For motors, I think it's something to do with carbon brushes on common types of motors that create arcs, which AFCIs are supposed to protect against. Might be confusing the sensor and since they're so new, they still suck at differentiating "good" and "bad" arcs.

http://en.wikipedia.org/wiki/Brush_(electric)

 

[phucheneh]

Power line transmission means the bedroom cable box communicates with a main box via a digital signal across the household wiring. If the boxes all have their own coax cable, then that's not it. Figured it was worth asking.

The 'good arc/bad arc' thing definitely seems like a hard thing to identify. Mayhaps the vacuum cleaner thing has to do with the arc plus the big magnet next to it...an induced current kinda thing, or some kinda weird frequency oscillation?

 

[BUTCH1]

You said "we re-wired" as in an electrician did it or you did it yourself?

 

[Ken g6]

Get a UPS and forget about it? I wonder if a UPS nullifies the effect of an AFCI?

 

[Red Squirrel]

Get a UPS and forget about it? I wonder if a UPS nullifies the effect of an AFCI?

Maybe a big dual conversion setup would but don't think a standard one would as it still passes the power directly through until the voltage hits the trip threshold.

An isolation transformer most likely would too. One way to work around this silly code is to just wire the breaker directly to an isolation transformer then feed off of it instead. Hey, it still has an AFCI, nothing mentions you're not allowed to shove an isolation transformer between each circuit. :biggrin:

 

[Imp]

You said "we re-wired" as in an electrician did it or you did it yourself?

Nope, it set us back $20k... Master electrician plus his apprentice did it, city or whatever inspector inspected it.

Get a UPS and forget about it? I wonder if a UPS nullifies the effect of an AFCI?

That MIGHT work, but why was it okay for over 2 years? I've read on Amazon reviews for UPS and more expensive surge protectors (Isobars) that hooking a treadmill up to one stopped an AFCI tripping -- problem signal from motor.

 

[stormkroe]

The code isnt't every 'outlet', it's 'branch circuits that supply receptacles in sleeping quarters for dwelling units'. CEC code 26-722 sub 'f'.
If the electricians had to have the inspector tell them to install your arc faults, they're corner-cutting A holes and also probably wired your house to not have them.
To avoid 'nuisance tripping', arc fault circuits should never include lights (or motor loads like your refridgerator). Did they use stab-lok or homeline?
Also, since it has already passed inspection, ther is NOTHING keeping you from switching it back to a $10 standard breaker.

 

[Red Squirrel]

The code isnt't every 'outlet', it's 'branch circuits that supply receptacles in sleeping quarters for dwelling units'. CEC code 26-722 sub 'f'.
If the electricians had to have the inspector tell them to install your arc faults, they're corner-cutting A holes and also probably wired your house to not have them.
To avoid 'nuisance tripping', arc fault circuits should never include lights (or motor loads like your refridgerator). Did they use stab-lok or homeline?
Also, since it has already passed inspection, ther is NOTHING keeping you from switching it back to a $10 standard breaker.

Interesting, so circuits that don't supply bedrooms are allowed without? I always thought it was everything that is not GFCI protected. So basically everything except for garage, outside, bathroom and kitchen.

Though TBH I think I would just go ahead and change it, especially if it's worked fine for all these years before it was added. If everything is wired properly there should not be any real dangerous arcing, and if by chance something got loose if it's done properly it's going to be within a junction box.

 

[stormkroe]

Interesting, so circuits that don't supply bedrooms are allowed without? I always thought it was everything that is not GFCI protected. So basically everything except for garage, outside, bathroom and kitchen.

Though TBH I think I would just go ahead and change it, especially if it's worked fine for all these years before it was added. If everything is wired properly there should not be any real dangerous arcing, and if by chance something got loose if it's done properly it's going to be within a junction box.

Yeah, in the US practically the whole residence has arc-fault requirements. In Canada, only those circuits that include receptacles in the sleeping quarters. Also, only receptacles within 1.5 meters from a sink require gfci, and garages dont require them at all. Outside plugs, and only if they are within 2.5 meters of finished grade (26-710 (n)).
I wonder if OP's corner cutters skipped out on the 'tamper resistant' receptacle code also?

 

[Imp]

The code isnt't every 'outlet', it's 'branch circuits that supply receptacles in sleeping quarters for dwelling units'. CEC code 26-722 sub 'f'.

If the electricians had to have the inspector tell them to install your arc faults, they're corner-cutting A holes and also probably wired your house to not have them.

To avoid 'nuisance tripping', arc fault circuits should never include lights (or motor loads like your refridgerator). Did they use stab-lok or homeline?
Also, since it has already passed inspection, ther is NOTHING keeping you from switching it back to a $10 standard breaker.

Okay, I just saw something about it being all outlets when I searched "arc fault scam" and "arc fault sucks" after finding out they're $90 a pop. Someone said something about it not making sense to just "arc fault protect" bedrooms, when every other non-protected circuit in the house could just as well kill you the same with a fire.

Good pick up (not sarcastic)... I honestly did not question the electricians' competency because they missed the new code addition. You're actually right because the master had his apprentice do most of the work. The apprentice cut into a massive timber support beam. Luckily, it's an under-engineered, massively overbuilt early 1900's house.

No idea what stab-lok or homeline is... Assuming it's the type of wiring?

From what I've been told, the AFCI is connected to a regular breaker in the panel. All it would take to remove the AFCI is to disconnect the it from the main box and maybe rewire something.

But to be a bit paranoid, is there much, if any, risk from not having AFCI circuits? It's supposed to detect old, leaky, arcing wires?

 

[Imp]

Yeah, in the US practically the whole residence has arc-fault requirements. In Canada, only those circuits that include receptacles in the sleeping quarters. Also, only receptacles within 1.5 meters from a sink require gfci, and garages dont require them at all. Outside plugs, and only if they are within 2.5 meters of finished grade (26-710 (n)).
I wonder if OP's corner cutters skipped out on the 'tamper resistant' receptacle code also?

I had to look those up... Definitely don't have ANY of those in the house.

The sink outlets have GFCIs though...

And you seem to know what you're talking about. What's your background?

 

[postmortemIA]

Get a UPS and forget about it? I wonder if a UPS nullifies the effect of an AFCI?

it solved my tripping of PC that has active PFC power supply..

 

[stormkroe]

I had to look those up... Definitely don't have ANY of those in the house.

The sink outlets have GFCIs though...

And you seem to know what you're talking about. What's your background?

I've been doing electrical and electronics for almost 20 years. I'm an Alberta Red Seal Master electrician. I own my own company, we wire everything from houses to commercial shops to medium (no more than 150 unit 5 story) hotels.

The Arc-fault is a type of breaker, not something connected afterward so it's a very simple direct replacement to install a standard breaker.
They were implemented in bedrooms because of the old practice of putting receptacles 'one for every wall' which usually landed them in the middle of the wall. People put their beds and dressers in the middle usually, and then cram the beans out of them to get closer to the wall. That squishes whatever cord is plugged in there, you get compressed wire insulator, and eventually a smoldering fire. Ironically, new houses under the arc-fault code usually have the plugs more corner-located and need the arc faults much less than the old houses.

Stab lok is a very common brand in Canada for houses, as in about 95% of all houses have them. For some reason they've (Schneider) quit making the panels and switched to Homeline sub-brand for the mainstream (although some people still use Square D and Seimens). I was asking because, if it's a Homeline and you find out that your arc fault breaker is faulty, I'll mail you a new one. I have about 30 or so in stock.
FYI, I hate arc fault breakers 🙂