Hi all, long-time lurker and first-time poster! I've stripped my living room walls back to bare brick so they can be replastered and, just there, hanging a couple of metres down one wall is a length of cable! It is 2-core cable, 10mm wide, with a lead casing on it. It is not attached to anything at the bottom end and appears to have been randomly severed and plastered into the wall. There are a couple of metal wall fixings holding it in place and what appears to be some sort of earthing device - 2 flat metal bars that screw together either side of the cable, with a small wire coming from one of the screw joints (about 2" long). The wire part appears to have a copper core - maybe an earth? This wire is just touching the mortar in the bare brick wall. When it is moved so that it no longer touches the wall the main fuse box trips out all the electrics.

I can't quite get my head round this - does this mean that the lead casing around the wires is live (as that is the part to which this strange bar/wire combo is attached)? Obviously I'm not an electrician, just a DIYer on a tight budget. I have no idea where this cable may lead to as the house has been rewired in the past (before I bought it) and the consumer unit is fairly modern and has more modern wiring with the plastic-type coating. My plan for tomorrow was to get started on the plastering...

Any advice or ideas on what to do with this cable and whether it is safe to just put it back into a plaster casing would be much appreciated!

A pic. would be useful...

Are you able to post a pic.?

Oh hi and thanks for responding! I've got a very poor pic (camera phone only, sorry). Since my last post, I've managed to snap off the (?earth) wire from the bar device and the only way to get the electricity back on was to attach a bit of proper earth wire to it!

Will try to post the pic in this reply... wish me luck!

-- Sat Jul 31, 2010 10:20 pm --

It took me forever to get my blinking phone to transfer the pic to my PC - grrrr! Will attempt to get a better shot.

-- Sat Jul 31, 2010 10:26 pm --

Hopefully this will be a better picture...

Are the 2 cores hanging outside the grey sheathing... or are they hiding further up the sheathing??

You will first need to identify the cable....

Turn off your trip switches for all your lighting circuits first, then remove the earth wire from the wall so it is not touching it... do any other switches trip?

Can you post a picture of your fuse box and tell us what would not reset until you earthed the old cable ?

Nick

The 2 cores are hanging outside the sheathing.

By 'identify the cable' I'm guessing that you mean I need to find out what it does? I am just off to follow your last instruction and shall return with the results of my research.

-- Sat Jul 31, 2010 11:03 pm --

Bright_Spark - I did as you said and everything worked normally! No idea what this means though...

Sparkydude - I will go and take a pic of the fusebox in a mo, but when it tripped out earlier it was the master switch on the box that was turning off. I never thought to try individual switches to see what happened with each one and it's a bit too dark now for me to have a go at that. I will try it first thing in the morning though (teenagers won't be hooked up to their Xboxes then either!).

So with the lighting circuits isolated everthing else works fine... sockets etc... & with the earth wire not touching the wall.

Here are some pictures of the fusebox.

I turned off the lighting circuits, removed the earth wire and nothing tripped. I turned the lights back on, with the earth wire still not touching the wall and still nothing tripped. I am now none the wiser!

-- Sat Jul 31, 2010 11:16 pm --

Oops, forgot to add the pictures!

So now you have everything working fine with the earth wire not touching the wall... is that correct?

Lol I think so! However the metal bridge/bar thing is still in contact with the wall - could that be earthing the cable? Or maybe it was just some freaky thing that happened earlier? Decorating is never straightforward and easy when you live in the house that Jack bodged! (apologies to any builders out there called Jack who aren't bodge-it merchants)

What is the cable below the fusebox with an earth clamp on it, it looks like the other end of the cable you have found?

I have a nasty feeling they have somehow used this old cable as a main earthing conductor.

Looks very suspect to me.

Nick

I'm guessing you mean the fattest cable (the one that looks like the 10mm flat grey one from the living room). It has a metal label on it saying 'safety electrical earth' or something similar and is attached to a green and yellow earth wire leading under and into the main fuse box. The other end of the cable is split so that the black wire goes into one of the white plastic boxes whilst the red wire goes into the other white plastic box (in the bottom right of the picture - one box is flatter and squarer, the other is more long and thin but juts out).

I know the meter man came and did something to the box a couple of years ago, but I can't remember what.

If it is what you are both suggesting, then why would the live end of the cable terminate halfway down the wall in my living room? The fusebox is in the cupboard under the stairs, if that makes a difference?

I've got another pic, the strange blue glow is from my LED torch.