External wiring help needed urgently.

[Kilm]

Hi guys,

I had an external light at my front door, which must've been there since the place was built in the 70's. Long story short, wind damage destroyed it and I bought a new fitting today.

Took the old one down and the wiring behind it was in an awful state. Held on by threads with plastic sheathing degraded, and the live wire snapped clean off as soon as I touched it.

I've given it a good pull but there's no slack coming out, so it can't reach the new fitting.

How do I make this safe? If it cannot be extended to reach the new fitting, my plan is to simply make it safe, shove it in the hole and polyfilla it.

I'm somewhat concerned as it's involving live wires, I have no lights in the house as it's off at the mains and I have a two day old daughter to worry about as well!

Any help greatly appreciated!

High res image here:

http://img196.imageshack.us/img196/4038/72q1.jpg

Untitled

• Kilm
• 13 Oct 2013
• 1

 

[BigJon]

Under the white tape is there a connector block?
If so can you disconnect the loops that were going to your light from that block and replace with new to your new light fitting, presuming the cables coming through the wall aren't damaged.

 

[Kilm]

Under the white tape is there a connector block?
If so can you disconnect the loops that were going to your light from that block and replace with new to your new light fitting, presuming the cables coming through the wall aren't damaged.

I bounded downstairs to check, and found this:

Image > http://img833.imageshack.us/img833/3889/5inu.jpg

So simple as that eh? Get some new cables, cut back the coating, insert, etc?

It looks a bit gimped though. Is it just a case of unscrewing each locking bolt thingy from the external side?

 

[steve4surrey]

You may not have to buy new cable depending on what is connected to your new fitting as these should be ok to fit to the connector block assuming it's in a good enough condition and you are able to undo the screws. Make sure that any connections are again covered in insulation tape and covered by the new fitting when fixed to the wall as you do not want water ingress.

 

[ban-all-sheds]

Insulation tape doesn't insulate, after a while it doesn't tape, and it never does much in the way of waterproofing.

Self-amalgating tape would be better, or clean out the hole in the brickwork, push the (new, clean) connector block into it, and fill with silicone sealant.

I have no lights in the house as it's off at the mains

So it's just on the lighting circuit like all the other lights?

Does the switch for it have both L & N there?

 

[Kilm]

Insulation tape doesn't insulate, after a while it doesn't tape, and it never does much in the way of waterproofing.

Self-amalgating tape would be better, or clean out the hole in the brickwork, push the (new, clean) connector block into it, and fill with silicone sealant.

I have no lights in the house as it's off at the mains

So it's just on the lighting circuit like all the other lights?

Does the switch for it have both L & N there?

Well, as is the trend with my luck, I tried to remove the connector block and the earth snapped away from the internal end!!

I decided that it'd be best to remove the block completely, and the end result is now this:

http://img543.imageshack.us/img543/30/qjdj.jpg

I have went through all the fuse switches on my mains box, and when I hit the lights one, all lights in the house go out, including the front external, so it seems so.

I have no idea what you mean by the switch having live and neutral there. Do you mean the main switchbox?

I suspect, having looked in my loft, that the wiring in this house leaves a lot to be desired and I think it's probably all one big loop.
The lights in the extension that was here when we bought the place constantly go, so I'm playing with the idea of getting it all looked at but I just can't afford it.

 

[Spark123]

I have no idea what you mean by the switch having live and neutral there. Do you mean the main switchbox?

The light switch that controls this light, can you upload a photo of the wiring in the back of it?

 

[Kilm]

Aaah I see. Let me go take the cover off.

 

[Kilm]

The pictures aren't great, but I think I'm beginning to understand this now.

So has the wiring for this effectively been fed off the main loop by doubling back from the switches for the hall / stairs?

http://img22.imageshack.us/img22/579/9r4e.jpg

http://img10.imageshack.us/img10/8232/xrys.jpg

http://img547.imageshack.us/img547/1028/s0cp.jpg

So if I find the right wires in there, take them out, then there's no power going to the external wiring?[[/url]

 

[Spark123]

It looks like it is an old system where the wires are insulated sleeved singles. The lives will probably loop around to each switch and the neutral around each lamp fitting.
A switch wire connects each light to the switch. Makes it a bit more complicated to isolate it fully, you can disconnect the live to the light (into a terminal block) in the switch leaving the loop intact but where the neutral is fed from is going to be harder to track down.

 

[Kilm]

Ok.

In this picture:

http://img10.imageshack.us/img10/8232/xrys.jpg

You can see a 'n' shape to the right.

The right hand switch is the outside light.

I've taken out the 'n' and it terminates in the right hand switch, and is bent double in the middle switch.

So if I cut it and terminate it in the middle switch...... that should be that, no?

It's the red cable that's in that 'n' shaped sheath.

 

[Spark123]

You could take out the link wire and move the loop wire to the centre switch so there is no supply to the switch for the outside light but doesn't get away from the neutral still being connected.
Tape up the wires outside for now as the neutral is still connected, you need to call an electrician as soon as possible to disconnect or sort it properly.

 

[JohnW2]

... or clean out the hole in the brickwork, push the (new, clean) connector block into it, and fill with silicone sealant.

'Ordinary' silicone sealant gives off various vapours (acetic acid and probably also water) whilst curing. Once cured, it's fine, electrically, but IME if one smothers a connector block with it, there can be quite a low 'insulation resiistance' (sometimes enough to trip an RCD) for the initial day or three.

Kind Regards, John

 

[Monkeh]

Insulation tape doesn't insulate

I seem to recall a figure of 45kV/mm. That's not insulation?

 

[Kilm]

You could take out the link wire and move the loop wire to the centre switch so there is no supply to the switch for the outside light but doesn't get away from the neutral still being connected.
Tape up the wires outside for now as the neutral is still connected, you need to call an electrician as soon as possible to disconnect or sort it properly.

So the live wire goes:

Hallway, stair then outside light.

If I take the live wire out of the outside light, there are still two wires leading away from it. One wire is the live wire leading to the light itself, and comes out of the same spot where the live wire ended, the other one comse out the bottom and I guess that's neutral?

Is there a chance that I'll be breaking the loop to the rest of the lights and is there any danger present in putting the live wire into the stair switch again?

More importantly, what are the chances of my house burning to the ground?