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#111315 - 11/05/06 07:52 AM Bad wiring in store (UK)
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
The wiring in this commercial establishment is such a mess it's hard to know where to start, so it may as well be with the service entrance.

These always tend to be messy here, but note the cables to the heating contactor (black box, lower left) just draped along the floor:



Here's the view slightly to the right:



The MEM 3-phase switch-fuse is no longer in use (everything is running on one phase), but still has power applied. Note the "deliberate mistakes" in the way it was installed:



Here's what's left of a light fitting, now suspended solely by the wiring. Note also the method of junction box wiring, which is repeated throughout much of the store:



The light and exhaust fan wiring in the W.C. area:


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#111316 - 11/05/06 07:54 AM Re: Bad wiring in store (UK)
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Here we have a mixture of power, telephone, and alarm wiring installed by the "minimal fixings" method:



This is the other side of the partition. The wire draped across from the fan actually goes to a PIR sensor for the alarm, which is just hanging on the far side of the fan. More loose cables to switches and the fluoro light can be seen in the background:



And this is the power source and controller for the fan in the last picture. Yes, that's "T&E" (Romex-like) from the plug to the switch:



More hanging cables, this time running into a small area at the rear of the store which has been partitioned off to form an office. Just about visible are more loose cables dropping down to the right of the black ring binders which go to a receptacle behind the cash register:



Here's where one of the above cables goes within the office, to feed the only functioning receptacle within the area. I think the saw is a nice touch! Oh, and notice the ingenious lighting arrangement too!



At this point I should explain that this was originally three separate units, so there are three electrical services, one of which is pictured above. The second is completely disconnected, with meters removed and just the service head remaining (now boxed in and inaccessible).

The third is at the rear of the store in the office area, and at first glance it appears that the 1.0mm cable draped into the office is taking power from this service out to some other part of the store:



However, this rear service is not being used, and apparently an "electrician" ran this cable through when the units were knocked into one to bring power to the rear area from the service at the front. So the cable you see here tapped into the load side of left-hand fuseway is actually now the supply for the rear lights:





[This message has been edited by pauluk (edited 11-05-2006).]

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#111317 - 11/05/06 10:57 AM Re: Bad wiring in store (UK)
mxslick Offline
Member

Registered: 10/24/04
Posts: 785
Loc: Atomic City, ID USA
In the first post, pic 5, the W.C. area, look at the junction on the left. Looks like some fire has already happened there.

What a mess!! And since this appears to be an automotive parts store, pity the fire brigade that has to respond when this wiring lights the place up for real.
_________________________
Stupid should be painful.

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#111318 - 11/05/06 06:06 PM Re: Bad wiring in store (UK)
Theelectrikid Offline
Member

Registered: 04/30/04
Posts: 854
Loc: Levittown, PA
I feel sorry for the guy in the WC when that wire touches off!

(That is, if I understand "WC" correctly.)

Ian A.
_________________________
Is there anyone on board who knows how to fly a plane?

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#111319 - 11/05/06 06:12 PM Re: Bad wiring in store (UK)
RODALCO Offline
Member

Registered: 12/08/05
Posts: 863
Loc: Titirangi, Akld, New Zealand
What a mess pauluk.

There is a fire waiting to happen here if not already.

That shop should be closed for a rewire by the labour department, certainly when the public has acces to that place.
_________________________
The product of rotation, excitation and flux produces electricty.

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#111320 - 11/06/06 08:07 AM Re: Bad wiring in store (UK)
trobb Offline
Member

Registered: 06/08/06
Posts: 111
Loc: Iowa City, IA
That fluor. lamp trick is familiar. Our church added cabinets in the basement, but simply cut the wallboard around the wrap for the fixture (they even matched the radius of the plastic!). Now we have 4 dead lamps and no way to change them short of demolition... Good luck if you plan to re-wire.

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#111321 - 11/06/06 08:58 AM Re: Bad wiring in store (UK)
Happy Birthday LarryC Offline
Member

Registered: 07/05/04
Posts: 776
Loc: Winchester, NH, US
Paul, please excuse this Yank's ignorance. Which box does what?

In the first picture, is the large grey box in the lower right the service entrance?

What are the 3 smaller boxes on top and why does one have three grey cables coming out of it?

I assume the top silver box with the 123 stickers is the cash register, but then what is black box with the display?

The second picture with the unused 3 phase disconnect and the two distribution panels, what are the black things?

Are there two cables cut off just below the storage heaters distribution panel? Are they live?

Thanks for all of the answers.

Larry C

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#111322 - 11/06/06 12:34 PM Re: Bad wiring in store (UK)
napervillesoundtech Offline
Member

Registered: 02/28/06
Posts: 144
Loc: Naperville, IL, USA
 Quote:
That is, if I understand "WC" correctly


West channel? Wayside chapel? there are so many jokes about that. Speaking of joke, that wiring is awful. A real mess. Tear it all out and start over, which someone may have a chance to do if it goes up in flames.

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#111323 - 11/06/06 12:47 PM Re: Bad wiring in store (UK)
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
 Quote:
In the first post, pic 5, the W.C. area, look at the junction on the left. Looks like some fire has already happened there.

I'm not sure if that dark patch is overheating or just shadows when I took the picture or an unpainted part. I'll check when I get the chance.

 Quote:
pity the fire brigade that has to respond when this wiring lights the place up for real

Well, the good news is that the local fire station is only about 200 yards away!

 Quote:
(That is, if I understand "WC" correctly.)

I think you do!

 Quote:
Good luck if you plan to re-wire.

Yep, the tenant asked me about "doing something" with the wiring after his insurance agent became rather unhappy. Of course, given the present state of the wiring the only sensible option is to rip it all out and start over.

 Quote:
Which box does what?

It must be a little confusing when you're not used to seeing this stuff, so let's see if I can explain it all!

 Quote:
In the first picture, is the large grey box in the lower right the service entrance?

Yes, the large black cable entering that service head from the right is the underground supply from the street. This is our standard 4-wire 415Y/240V system.

 Quote:
What are the 3 smaller boxes on top and why does one have three grey cables coming out of it?

These are part of the service head and are pull-outs which contain cartridge fuses (60A each phase in this case). There are always PoCo-owned (and sealed) fuses between the supply and the meter here, whether a 3-phase commercial service like this one or a 1-phase residential.

The connections to the right of the fuses, still part of the service head, are to the neutral.

There are actually only two cables going to the right-hand fuse:

Click for closer view

One of these loops down to the small black fuse holder on the right, and from there a smaller cable (along with a similar-size cable from the neutral) runs to the black box to the left of the meter, which is a timeclock. This is used to turn on the power to the storage heaters at night via the contactor which is the other black box at the bottom.

The cables bringing power out from the meter (you can see the three phases taped red, yellow, and blue) are looped behind the board and are the four gray cables you can see emerging in a bunch on the right, along with the two earth conductors which are connected to the neutral.

On the latter point, this is a PME or TN-C-S system, which is similar to the usual American grounding system except that this is the only point at which the the bond is made. Neutral and ground are kept strictly separate from this point onward, even in the main distribution panel.

 Quote:
The second picture with the unused 3 phase disconnect and the two distribution panels, what are the black things?

They are just heavy-duty junctions, commonly called "Henley blocks" for the name of a common make. There are two separate block in each unit, so the one on the left is being used to join one phase plus neutral (the one on the right is unused).

So, two of the phases coming from the meter run directly to the now-unused 3-ph disco. The third phase and the neutral are then tapped at the Henley block to go to both the 3-ph unit and the 1-ph main panel on the right.

 Quote:
Are there two cables cut off just below the storage heaters distribution panel?

No; it's not too clear from the photo but they actually turn and go into the heating panel.

One runs directly to the Henley block to pick up the neutral. The other (just about visible in the dirt at the bottom of the wall) runs back to the contactor, and of course the other cable from the contactor is the remaining cable you can see here which is tapped onto the phase.

Unfortunately, this sort of messy service equipment is all too common.

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#111324 - 11/06/06 12:49 PM Re: Bad wiring in store (UK)
wa2ise Offline
Member

Registered: 11/29/02
Posts: 771
Loc: Oradell NJ USA
It does look a little strange to us Yankees (and Mets too) that individual wires there are not in some form of raceway. Like conduit, or such.

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