Connecting to an old lighting cable

[beinerts]

Hi all,

I've got an old style lighting cable in a wall, with a metal sleeving around it, which acts as the earth. There is no earth cable on the inside. My question is, how do I connect to this?! The only ways I can think of to get an earth connection would be to solder or clamp something onto the sleeve. does anyone know of any parts/methods that are suitable.

Thanks.

 

[ban-all-sheds]

Where/why/what for do you need an "earth connection"?

If the conduit is properly installed, i.e. bushed into the back boxes, continuity back to to the CU maintained etc, you can connect the earth terminal of an appliance or accessory etc to the screws in the boxes.

If it's not been properly installed, or if numpty modifications over the years have damaged its integrity, then you're hosed.

It's been many years since conduit systems like that were common, and I doubt you have the equipment needed to check that you have cpc continuity. Also, it's quite possible that the conduit never was an earth - lighting circuits didn't always have them. All in all I strongly advise getting an electrician to do a full inspection of your entire installation.

 

[beinerts]

Thanks. As you say, it may be OK. There is a bracket holiding it down, which is connected to the mounting box. I'll get a pro in who can properly test the integrity, though.

 

[ban-all-sheds]

Good idea, because if it's not OK and you proceed as if it were there could be a fatality.

Is the conduit round or oval?

Could you post a few photos of the insides of some back boxes (switches and ceiling roses)?

 

[beinerts]

I'm at work, so can't post any pics now. It's actually the cable that has an earth sheath, it doesn't have a seperate conduit. It's round.

 

[beinerts]

OK, there's a new topic on rewires Sounds drastic, but there are so many things that "might" be dodgy, due to age that I'm biting the bullet. Any input on that thread is much appreciated...

 

[timtheenchanter]

I still have the old metal conduit in my walls, new cabling though, get it checked out, there may be no-need for a re-wire, just some stuff added to bring it up to par.

for example, my house was checked, and fine 18 months ago, there ARE earths on the lighting loop, but NOT at the switches (just the switch wire coming down/bk) apparently this is fine, unless I want to add metal faceplates

 

[ColJack]

are we talking pyro here then? copper "sleeve" to the cable? or is it lead?

 

[RF Lighting]

I can only think of pyro or lead which fits the bill.

I think it's time for a picture...

 

[flameport]

Pyro seems likely, given that:

There is a bracket holiding it down, which is connected to the mounting box.

Lead covered cable would be 60+ years old.

 

[Paul_C]

Lead-sheathed cables were also used with clamps at boxes to provide the earth connection.

 

[sparkwright]

I'm at work, so can't post any pics now. It's actually the cable that has an earth sheath, it doesn't have a seperate conduit. It's round.

he says it's round, suggests probably pyro.