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#122389 - 11/02/05 10:07 AM Arcing in box (UK)
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Here we have an example of one of the problems of our shallow light-switch boxes (this is the standard depth of 1/2 inch).

The arcing which has taken place here could have been due to a loose wire or skinned insulation, but from the location of the marks, my money is on a conductor being trapped and nicked as the switch was jammed into the box.

Oh, and there's also a code violation here as well.



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#122390 - 11/02/05 10:31 AM Re: Arcing in box (UK)
britspark Offline
Member

Registered: 05/28/05
Posts: 54
Loc: southampton united kingdom
Paul,
whats that stray 6491x doing in that box?

Britspark

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#122391 - 11/02/05 10:46 AM Re: Arcing in box (UK)
Trumpy Offline

Member

Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
Hmm,
I'm guessing that the Code violation has something to do with either the box not being Earthed or if that 3-Core is a 2-Way switch wire, the green wire should be a different colour.
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#122392 - 11/02/05 01:33 PM Re: Arcing in box (UK)
Larry Fine Offline
Member

Registered: 02/18/05
Posts: 684
Loc: Richmond, VA
I wish we could get ahold of cable with colors like that here for 240v circuits and switch loops. No more recoloring white wires!
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Fine Electric Co.
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#122393 - 11/02/05 04:38 PM Re: Arcing in box (UK)
classicsat Offline
Member

Registered: 11/23/02
Posts: 449
Funny you don't have it there in the USA, but they do make a 12/2 Red/Black NMD-90 for the Canadian market, and it is rather common in the home centers I've been in. It was I think originally made for wire in 240V heaters, but I have seen it used for other 240V loads and switchloops.

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#122394 - 11/02/05 05:22 PM Re: Arcing in box (UK)
e57 Offline
Member

Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
Larry you can get it here, just no one stocks it, and rarely ever uses it because tape or 3-wire is much faster, and cheaper than special order wire.
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#122395 - 11/03/05 03:25 AM Re: Arcing in box (UK)
Texas_Ranger Offline
Member

Registered: 12/17/01
Posts: 2343
Loc: Vienna, Austria
The violation has to be the single red wire going up. What was it for? Added three way?

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#122396 - 11/03/05 03:44 AM Re: Arcing in box (UK)
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
 Quote:
I'm guessing that the Code violation has something to do with either the box not being Earthed or if that 3-Core is a 2-Way switch wire, the green wire should be a different colour.


The green was actually connected to the earth terminal on the box -- I'd already removed it before taking the pictures (it's actually the bare earth conductor with green sleeving on the end).

 Quote:
whats that stray 6491x doing in that box?


For the benefit of non-UKers:
6491X = Single-insulated cable of the type normally pulled into conduit.

 Quote:
The violation has to be the single red wire going up. What was it for? Added three way?

You've got it! The added single was on the switch common with the red/black in the cable used as travelers.

 Quote:
I wish we could get ahold of cable with colors like that here for 240v circuits and switch loops. No more recoloring white wires!


Strictly speaking that black wire should have been remarked red, as black is (was) our neutral color.

We have cable with two red conductors, intended specifically for use on switch loops, although in my experience it's very rarely used.

Unfortunately neither red/black nor red/red will be available for much longer as we change over to the new brown/blue color code.

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#122397 - 11/04/05 04:58 AM Re: Arcing in box (UK)
Out Of Phase Offline
Member

Registered: 11/02/05
Posts: 20
Loc: Wiltshire, England
That single 6491x cable should be a double insulated single. If that was used, and the box was wired neatly and laid in carefully the job would of been ok.

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#122398 - 11/06/05 07:04 AM Re: Arcing in box (UK)
DougW Offline
Member

Registered: 06/08/03
Posts: 1083
Loc: North Chicago, IL
The real problem, of course, is stamped on the inside of the box:

 Quote:
MADE IN ENGLAND


j/k!

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