Advice on bathroom light fitting on old house wiring

[Gregmonilola]

Hi there, I'm a first time poster so apologies if this question has been posted or talked about before. 

My problem is I want to change my old light fitting in the bathroom, it's currently just a plastic and metal light bulb holder directly onto the ceiling, with a new chrome LED light fitting. 

My house which was built in 1979 has metal conduit style earthing so as such doesnt have earth wires. The new light is a Class 1 product and must be earthed and is suitable for use in zone 2 and outside zones of a bathroom.

How do I connect earth wire of the light to the black box inside the celing?

Thanks for any help given.

 

[ProDave]

A ring terminal and a screw to connect to the conduit box.

 

[Sharpend]

Take pics before you disconnect so that you can refer when reconnecting. 

 

[Bruspark]

I think the question was how to deal with new light fittings where they require an earth via CPC  but in older lighting installations one doesn't exist

Comment:  Not all old  'earthed' conduit turns out to be very well earthed - this will need testing

Easiest solution:  Get a double insulated fitting instead.
Worst solution:   Run CPC from nearest 13A socket (seriously you have no idea how much trouble this might cause later . . )

Most expensive Solution :  Electrician to  run new CPC from consumer unit (and test) to all lighting on the circuit 

 

[Spoon]

Worst solution:   Run CPC from nearest 13A socket (seriously you have no idea how much trouble this might cause later . . )

Most expensive Solution :  Electrician to  run new CPC from consumer unit (and test) to all lighting on the circuit 

If running a separate CPC then this will have to be 2.5mm, if mechanically protected or 4mm if not.

 

[ProDave]

I think the question was how to deal with new light fittings where they require an earth via CPC  but in older lighting installations one doesn't exist

Comment:  Not all old  'earthed' conduit turns out to be very well earthed - this will need testing

Agreed it needs testing.

Proper threaded conduit rarely gives any issues. but I have seen a lot or carp lighting conduit that just has a basic metal clamp to join the boxes to the conduit and I have seen those where the conduit has pulled out.

 

[Rob.]

The conduit box will have a threaded hole in the bottom, use this to connect your earth (CPC).

Dependent on age the thread could be BA rather than MM. 

It does need checking that the conduit earth is still intact. 

For the cost of a a call out an electrician would install the light and prove the earthing is safe. If it's not, then you know about a problem that could be potentially fatal in the future and they can advise on a suitable solution. 

 

[Gregmonilola]

The conduit box will have a threaded hole in the bottom, use this to connect your earth (CPC).

Dependent on age the thread could be BA rather than MM. 

It does need checking that the conduit earth is still intact. 

For the cost of a a call out an electrician would install the light and prove the earthing is safe. If it's not, then you know about a problem that could be potentially fatal in the future and they can advise on a suitable solution. 

View attachment 10166

Yes we have this inside the box in the ceiling, it has  scree inside it, but it does not have anything connecting to it from the old light fitting. We had an electrician from my work come and upgrade the fuse box to a new box last year, as we were fitting a new kitchen, he also was moving wall sockets and adding more sockets and also upgrading the shower cable to a 10mm t and e whilst we were doing the kitchdn work, he did say it was an old system but it was in good health. 

 

[kerching]

Did you receive any paperwork when the board was upgraded?( by the way, unless you are in Scotland, this work is notifiable to Building Control)paperwork should tell you/us , in the Test Reaults section , IF your earthing is adequate....post a pic of the schedule and test results on here for us to look at. A pic of your new fuseboard might be handy ( just lift lid up and snap a pic, don't go unscrewing any lids or anything as it could end in tears)

 

[Gregmonilola]

We are in Scotland, so we didnt get any paperwork, if a knew how to post a photo in here I would. How do i upload a photo, i just get the options for inserting an url or insert an exisying attachment.

 

[ProDave]

We are in Scotland, so we didnt get any paperwork, if a knew how to post a photo in here I would. How do i upload a photo, i just get the options for inserting an url or insert an exisying attachment.

So no need to notify building control, but he still should have given you an EIC with a Schedule of Test Results.

You can't upload photos until you have made 10 posts unles an admin comes along to enable it. It's an anti spam measure I believe.  But if you can upload them to a photo hosting service you should be able to post a link.

 

[Evans Electric]

Just an extra point ,  save the  two screws that fit the conduit box for use with the new fitting.