arc from child-proof outlet plate
Electrical code now calls for arc-fault interupted breakers to bedroom outlets. Good thing. Ours tripped, so we new there was problem before finding out the hard way. Here’s what we found.
You know those child-proof outlet covers that have a spring-loaded cover plate. A cover slides across the slots when a plug is not in place. And to plug something in, you have to drag it open a couple of mm. These covers also cut drafts and look uncluttered.
Well, the hot screw on the recepticle had come into contact with the side of the box (technically the metal fins holding the box into the previously-finished wallboard).
Two things are to blame in combination. One is the fact that the metal hold-in tabs protrude into the box ever so slightly. But the final link in the chain was, I suspect, the spring on the child-proof plate was strong enough to slip the recepticle a bit sideways on its mounting screws, out of its carefully centred position. It wouldn’t take a huge -straight lateral – force to do this even when the screws are well tightened.
I’m just curious if anyone else is aware of concern about the spring-loaded covers and/or the finished wall mounting fins. The fins on their own do take up some space in the box and they are also a bit sharp should the wire jacket abrade against them.
Thanks in advance for my continuing education.
Replies
I'm not exactly sure what you're calling mounting fins.If you're talking about the clips that are used when a box is cut into an existing wall,that slip in next to the box, pull against the back of the drywall and wrap around the box edges....around here they are called Madison clips,and yes they do suck.They never give the same strength as a box nailed or screwed to a stud during the original rough-in.They depend on the strength of the wall surface material to resist the pressure of people pushing and pulling on cord caps.And you're right that it's never good to add conductive metal to the inside of a box.I think it's a good habit to always tape receptacles as a bit of extra insurance.When we have to cut a GFCI receptacle(extra wide and deep) into an old work box using Madison clips,there is almost no room between the conductive parts and the box.
I worked on a job where we had about a dozen boxes above a particular countertop and the owner had somehow ended up picking an extra high backsplash,which would have run into the bottom of our receptacle plates.The general contractor wanted to mud the boxes in and have us cut new ones above them.My boss thought of us having to come back for call backs on loose receptacles from the old work box/Madison clip combinations working loose,and insisted that the GC remove the drywall and let us do the change properly.
I can't speak to the force that the child proof covers exert on the receptacle,I've never seen it.
Those child=proof covers need to be mounted to a very secure box. Square D has recalled there arc=fault ckt. bkr. line due to a faulty chip...their rep. claims the chip is universal to all arc-fault brks. If you have the square d cb any distributor will exchange it.
Thanks for tips. Our panel is Siemens and the breaker is fine. Didn't know the terminology "Madison" clips, but that's it. Used three kinds of retrofit box depending on depth available etc, and all sucked. However, the very solid gyproc+full plaster walls have been up since 1940 and deserved to stay up.
Taping is a very good idea.
I ALWAYS wrap tape around the fixtures - outlets, switches, whatever. Takes one minute and about 1/100 of a cent in tape and saves lots of time on opening up the box again in the future. Learned it on my first electrical-assistant job and have done it since.
Bill, out of the trades for years.
For future reference: I have had very good luck using the Pass&Seymore cut-in boxes (the grey ones) in both 18ci, 22ci, and 2 gang sizes. The "ears" are metal and the screws are long enough so they work in gyprock/plaster or lath/plaster.
"Square D has recalled breakers...common to all..."
Pausing to consider this, do you mean they won't offer promised protection? I'll e-search that. They're expensive, so I'd like to have one that work as promised. This one worked on cue, wouldn't reset until the problem was fixed and now is reset and on.
They have a replacement circuit breaker for all their orginal arc-fault cb's, I can't speak for Seimens but I will check for you tommorrow....as with the King heater debacle a few years ago the manufacturer provides the replacement not the service call if you need an electrician.
That's great of you. Thanks.
As of 5:00 pm, pst, my local seimens distributor informs me they know of no problems with their arc-fault cb, glad to hear it did its job, sometimes those of us in the field think new applications and code requirements are a bunch of hooey...