NEC Should Ban ALL backwiring methods
I”m currently working on this house for a client. They had a receptacle catch fire. Nothing was plugged in it. The wife just came down the basements steps and saw smoke coming out the wall. FD came, found the problem, a bad receptacle.
No determination was made as to why the receptacle went bad. However, they had an old 100amp Federal Pacific panel which are fire hazards to begin with with their faulty breakers.
What I suspect occured is this: I’ve noticed that backwiring was often done in the house. I suspect that a hot wire popped out of the hole through normal use of the receptacle and shorted against the metal box, overheating the wire and eventually starting the fire. The client is having me check the receptacles throughout for wiring problems during which I noticed backwiring was done often.
I pulled one receptacle out today and the grounded conductor (Neutral) was in the hole it belonged in but it pulled all the way out as I extended the receptacle outside the box. I attempted to push it back in the hole. It wouldn’t grip. The blade in the hole would not catch the wire at all. In addition, I noticed a hot wire was bent sharply (from being compressed in the box) and halfway out of its hole.
NEC has banned backwiring for 20amp circuits. If it’s not good enough for 20A then why on earth do they consider it good enough for 15A? They should ban it outright and manufacturers stop. A persons house almost burnt down and the evidence suggests it was due to backwiring.
Replies
Thats an interesting story. However I don't know very much about wiring, so because I am interested I must ask, what is backwiring?
Thanks.
You can refer to the answer provided by IBEW. He made a further distinguishment than I did. The stab in connectors and provided on the backs of receptacles. It's a little hole that you can insert a straight piece of stripped conductor into. When you do there is supposed to be a little blade that catches on the wire. This is all internal of the receptacle, you don't see it. All you see is the wire stick from the back of the receptacle. Should you have to retract the wire, you must use a narrow blade screwdriver to push a pin which releases the blade and allows you to retract the wire. This method allows you to avoid having to bend each conductor into a fishhook and seating it under the terminal screw and then screwing the screw tight against the conductor. Basically, it's a time saver thing.
True backwiring is different. In the same manner there is a hole in the back of the receptacle. However, that is where similarity ends. Once you push the wire into the hole, you then begin turning the terminal screw on the side of the receptacle which is threaded to a metal plate. As you do so the screw pulls up towards itself the metal plate until the plate tightens against the receptacle wall in effect sandwiching the conductor...kinda like a vice in a way. They're very good solid connections. The time saved is really only the part of having to fishhook the wire...you still have to turn the terminal screw so no times saved there.
The previous method, the stab in method, in my opinion should just plain be banned. There are valid reasons it was done for 20A circuits and those reasons as far as I"m concerned are just as valid for 15A.
Pyroman,
The receptacles you are describing are sorry because they are the stab-in type, not just because they are backwired. On commercial jobs with stranded conductors,the best kind of receptacles are backwired.Instead of the cheap little stab contact,the screw on the side firmly compresses the wire with a small plate.They don't pull out. Sidewired receptacles are good with solid conductors(like Romex) but not with stranded.There's a trick that everybody uses to wrap the strands around the screw, with a piece of insulation left on the end to keep them from unraveling, but it really makes for a cob job. Even if the inspector will accept it.
Yeah the stab-ins suck, but the code making panels are full of manufacturers and contractors with a need for speed.
I agree. I don't use they even if they are on the devices. Every month I make good money correcting problems with these terminations made by less enlightened electrical crews. Easy money redoing something that should have been done the first time.
IBEW, my mistake for not m aking the distinguishment you made. INdeed these are the stab in connectors to which I was referring. I am familiar with the backwiring method with the plate and so forth. You're right, that method is fine and great. I see those connections a lot on GFCI outlets and in fact all the GFI's I use are like that, there is no alternative to wire them under the screw.
I"m getting more biased against these stab in connectors. No offense if you use them for speed, but I can't see why any pros would use them. I've seen too many times where the wire is very stressed and there have been times I've been able to pull them out with a slight tug anyways. Call me old school, but wiring them under the screw seems like the best way and offers cheap insurance of a troublefree connection. Little more time, yes, but it's also cheap insurance in case the homeowner decides to fuss with an outlet and decides he better not and puts it back in and then......... oops.
To be a little more clear: I don't EVER use the stab-in receptacles . You're right about them, they are a pathetic excuse for a proper wiring method.My point about them not already being outlawed already, is, that the NFPA code making panels are weighted with the people who find them fractionally more profitable to produce,and by contractors who think the sky would fall in if they had to pay their electricians to actually wrap the wire around the screw,and then tighten it.
Barry
IBEW......OOoooooohhhhhh, I see. I misunderstood you at first. Thinking you did use stab-ins. Glad to hear you don't.
I understand what you mean about the panels being weighted in favor of the more ridiculous ideas. Heck, ya have that everywhere. But I"ve always understood revisions to the NEC can be made when many electricians decide to speak their voice on issues. At best that is what I was hoping for.