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#9342 - 04/25/02 02:33 PM Little Shop of Horrors  
pauluk  Offline
Joined: Aug 2001
Posts: 7,520
Norfolk, England
My next-door neighbor has just rented a shop in town, about 5 miles away. She asked me to take a look at the wiring as she was concerned about outlets, switches, etc. hanging loose off the wall. If only that were the problem.

I started opening a wall switch in the kitchen and was surprised to get quite a tingle when I grabbed hold of the plate screws (fortunately I was fairly well insulated from ground at the time!). A check with my meter to a nearby water pipe revealed 240V to ground on the metal fixture box.

After pulling the circuit fuse at the panel, I found the branch circuit had a hot-to-ground short on it. This 5A lighting circuit fed four fluorescent lights at the rear of the shop, all within easy reach and all of which had been operating with the metal casing live at full line voltage, even when switched off.

"I was about to take a damp rag and clean them," said my neighbor. [Linked Image]

On opening the distribution panel, I found that the ground wire on the cable (equivalent to Romex) was cut short to about an inch and folded back against the outer sheath. No wonder the fuse hadn't blown!

Now, I suppose it's possible that someone never connected that wire to the ground bar in the box, but I can't imagine why. The other likely scenario I leave you to guess for yourself. [Linked Image]

It doesn't end there, however. In the kitchen were two countertop receptacles, which someone had tapped into the same circuit. The fact that two 13-amp outlets shouldn't be put on a 5-amp lighting circuit pales into insignificance beside the fact that the ground pins on these recepts. were also hot, and a small, metal-cased microwave oven had already been plugged into one of them ready to use.

Just to top it all, I found a recept. on another circuit which was reading 240V on the ground pin. "Here we go again," sprang to mind, but it turned out to be a corroded cable at a junction box which had been on a damp wall. The bare ground wire had corroded right through and the end going to the recept. was against a hot terminal.

Apparently the landlord didn't seem too concerned about all of this.

[This message has been edited by pauluk (edited 04-25-2002).]

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#9343 - 04/25/02 07:54 PM Re: Little Shop of Horrors  
sparky  Offline
Joined: Oct 2000
Posts: 5,311
sounds like some fast& careless work there...

#9344 - 04/25/02 09:10 PM Re: Little Shop of Horrors  
circuit man  Offline
Joined: Nov 2001
Posts: 273
[Linked Image]talk about little shop horrors, try BIG!suprised someone hasn't been killed. hop you got it straightned out. [Linked Image]

#9345 - 04/26/02 05:42 AM Re: Little Shop of Horrors  
pauluk  Offline
Joined: Aug 2001
Posts: 7,520
Norfolk, England
Yes, I wrote a report for the rental agent to give to the landlord pointing out that his faulty wiring could quite easily have killed somebody. It's a serious matter, but I couldn't help smirking when I saw a clause in the contract to the effect that "the tenant is responsible for maintaining the electrical system in a good state of repair and must ensure that it is not overloaded."

I couldn't pinpoint the location of the short without tearing open walls and floors, so I just abandoned the circuit and ran a new one in trunking to the rear of the shop. And rewired those receptacles onto another circuit, of course. [Linked Image]

Only charged £80 (about $120) for the whole job, but the landlord still grumbled about paying the bill.

#9346 - 04/26/02 08:18 AM Re: Little Shop of Horrors  
CTwireman  Offline
Joined: Feb 2002
Posts: 840
Connecticut, USA
What is trunking made of? Plastic or metal? We have a similar system here that you may be familiar with- its called Wiremold, and it comes in metal and plastic varieties, though I have yet to see the plastic stuff being used.

I remember seeing some shoddy wiring in restaurants and other commercial buildings on a family visit to London a while ago. Well, at least it looked shoddy from an American standpoint. For example, in the place we stayed in, I remember that the cables feeding the outlets were stapled right onto the baseboard and mouldings! Not exactly protected from damage!


#9347 - 04/26/02 06:47 PM Re: Little Shop of Horrors  
pauluk  Offline
Joined: Aug 2001
Posts: 7,520
Norfolk, England
Trunking comes in PVC and steel of various sizes. The plastic variety is most common due to lower costs, except in industrial environments where the extra protection against damage is needed (e.g. factory, garage, etc.).

Yes, cables clipped direct to the baseboard ("skirting board" in British parlance) or to walls are very common here, probably because so many of the walls in our buildings are solid masonry so chaneling out for cables can be a very labor-intensive and tiring job. That's where the surface trunking is very useful and makes a much neater job. The smallest size is about 5/8" square, the next about 1 x 5/8, so they're not too obtrusive (and can be painted over anyway).

[Edited for typos.]

[This message has been edited by pauluk (edited 04-26-2002).]

#9348 - 04/27/02 08:06 PM Re: Little Shop of Horrors  
CTwireman  Offline
Joined: Feb 2002
Posts: 840
Connecticut, USA I guess it wasn't shoddy after all. Still, the thought of a 240 volt cable without protection is scary!


#9349 - 04/28/02 06:54 AM Re: Little Shop of Horrors  
pauluk  Offline
Joined: Aug 2001
Posts: 7,520
Norfolk, England
I think this is one area where American practice is to a much higher standard than here.

I don't know if you saw any domestic main panels/services while you were over here, but I think you'd find those to be quite different as well: No conduit or raceway on the incoming cables, for example.

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