Electrical question

[plasticpigeon]

Hello. I'd be very grateful for suggestions on how to fit an earth to old ceramic ceiling roses. I wish to use these roses to hang some simple pendant lights, which will be just a flex with and bulb holder and shade on the end. However these old ceiling roses only have 2 connections for the live and neutral wires and have no provision for an earth cable to go through. There are 2 screw holes for fixing but I wouldn't want to use one for threading the earth through as I don't think one lop sided fixing would be sufficient. As I would like to use metal bulb holders, I'd have thought an earth would be essential. Is there a way round this. Are metal bulb holders ok without an earth or alternatively can anyone think of a way of attaching an earth. I cant see a way unless i drill a hole in the ceramic rose!!! I can post a picture if that would help. I suppose I could use bakelite, but it's not what I wanted

 

[Feltwell]

As it happens, I've just fitted some ceiling roses and metal bulb holders pretty much as you describe, that I bought as a pre-wired set.

My ceiling roses were metal so had an earth terminal on the back of them - however I see no reason why you'd need one on a ceramic rose as it's an insulator.

A metal bulb holder definitely requires an earth, so your twisted cable that drops down to it needs to be 3 core. The bulb holder itself should have an earth terminal on it. That earth will run straight back to the junction box in the circuit, I presume you're not "looping in" at the rose.

For a much more qualified opinion ask Zebra!

 

[88v8]

Some of these ceramic roses have three terminals. I have some, somewhere.

An earth is desirable, although I used metal holders for 30 years without. The old holders have no earth provision anyway.
You can just run the earth wire from the holder into the rose and attach it to a 1-way junction block (wrap in insulation tape) that sits in the screw-on ceramic cover.

Alternatively, electricians nowadays also use crimp terminals similar to those used on the car.

And if you can access the space above, you can hook it in with the Ashley J501 J-box.

http://www.ebay.co.uk/itm/Ashley-J501-Low-Profile-Torpedo-Shaped-Downlighter-Junction-Box-16A-/261153447306?pt=UK_BOI_Materials_Supplies_Electrical_ET&hash=item3ccdf55d8a

Ivor

 

[plasticpigeon]

Thanks Feltwell, but the problem is not earthing the rose, but getting the earth wire through the rose to earth the bulb holder!!!! I have 2 different types of wiring in my house. Upstairs I think is what is termed loop in where the twin and earth goes to the roses and the switch cable is just a live and switched live. Downstairs is stranger, with lives running through the switches and neutrals round the roses, so the switch wire is just a single core switched live. In a way this is neater as there are fewer connections at the rose. Here is a picture of the rose I'm hoping to use.

 

[plasticpigeon]

Hello Ivor, to have enough space to put chocolate box type connectors under the screw on cap did you remove one of the brass terminals from the ceramic base and put two of the wires (in my case it would be the neutral and earth) through the hole and make the live connection on the terminal on the other side?

 

[Feltwell]

I see what you mean now!

If you take the terminals out of the ceiling rose completely, does that give you enough holes to run a 3 core cable direct from the bulbholder, through the ceiling rose to a junction box in the void above the ceiling? You can always untwist a braided cable

You'd obviously need to make sure the cable was well secured in the rose to stop any possible strain on the connections at the junction box.

Are you using twisted cable to your bulbholder, similar to the link below?

http://www.lampsandlights.co.uk/flex.php

 

[Lime]

Unfortunately the simple answer is that you can't do what you want to do, not without dismantling the brass connections within the rose.
The exposed brass connections do not comply with the regulations.
The "two plate" ceiling roses you show do not allow an earth to enter them so the only alternative for you is to have an external earth wire.. but that would neither look good nor comply with the average electrician's interpretation of the regulations.
If you remove the internal brass connections completely and are able to run the cable with sheath into the rose you could use a terminal block (of the chocolate kind).
If you are not able to run the cable in with its sheath then you could use single sheathed wire connected via a junction box but, once again, electricians may call it into question.

The "three plate" ceiling roses mentioned by 88v8 were used where the live wire was brought into the rose together with a second switch wire (neutral being the third).
As I stated earlier, the brass connections are able to be touched when the rose cover is unscrewed and do not comply with the regulations.

In my early days of electrical work I encountered more ceramic two plate roses used as house fuses than for suspending lights from.
Sometimes 4 or more would be mounted on a large wooden board with two ordinary brass light switches as the main switch sometimes ganged together sometimes not.

 

[Owain]

The connections on the ceiling side of the rose must be enclosed in a non-combustible enclosure, so you must flush in a BESA box into the ceiling and mount the rose on that.

eg. http://www.tlc-direct.co.uk/Products/CO20BX1.html
or http://www.tlc-direct.co.uk/Products/MT20BX1.html

If you use the metal one it must be tapped and have an earth terminal fitted.

If you can dismantle the terminals out of the existing rose and use 3 holes for wires you can run to a terminal strip in the BESA box and connect there.

It is possible to get modern double-insulated metal lampholders, but I can't find one online right now. You might clarify if this one is double insulated as it doesn't say earthed
http://www.lampsandlights.co.uk/moredetails.php?ref=lhantique12

 

[Penners]

If you can dismantle the terminals out of the existing rose and use 3 holes for wires you can run to a terminal strip in the BESA box and connect there.

That sounds like a sensible and safe solution. The ceramic ceiling rose becomes simply cosmetic.

 

[plasticpigeon]

Thanks for the replies, I'm getting the picture now that if I want to use these then I need to take out the original terminals and then I will be left with 4 holes. What do people think of the idea of mounting the rose on a pattress with a large circular cut out in it. it would then be possible to put the braided wire from the bulbholder through the ceiling rose and join the wires to the lighting circuit with chocolate box connectors within the void in the wooden pattress on the room side of the ceiling rather than in the ceiling void. I've just disposed of a load of old ceramic switches as I wasn't happy with the terminals being exposed when the top was spun off and I'd really like to be able to use these!!!!

P. S. does anyone know approximately what era these ceramic roses are from. My guess is 20s or 30 but I'm not sure.

 

[Penners]

The connections on the ceiling side of the rose must be enclosed in a non-combustible enclosure, so you must flush in a BESA box into the ceiling and mount the rose on that.

Note what Owain says above.

 

[88v8]

Depends how bothered you are about t'Regulations, or whether you just want something that's safe.
I'm happy to use brass/ceramic switches, although in my latest installation I have for the first time earthed them. The fact that they're live when the tops are spun off, I don't care a hoot. Don't spin the tops off, then they're perfectly safe....
I also mounted them on an elm patress, and I've used elm and oak patresses for power points, I suppose they also don't conform huh.

I care even fewer hoots that the terminals on a ceramic ceiling rose are live... it's on the ceiling for heaven's sake, mutter mutter.

However, I take your point that one can't actually get an earth wire into the rose, sorry, hadn't thought of that. So, If one uses a plastic bulb holder, it doesn't need an earth. Not the ugly modern white ones, but one like this
http://www.ebay.co.uk/itm/1-OFF-SLEEK-BLACK-BC-BULB-HOLDER-SOCKET-BRAND-NEW-UK-FIT-B22-BC22-BC22d-/200782857611?pt=UK_Antiques_Architecural_RL&hash=item2ebf97458b

The same chap also sells new brown bakelite ceiling roses.

Ivor

 

[Owain]

If you can dismantle the terminals out of the existing rose and use 3 holes for wires you can run to a terminal strip in the BESA box and connect there.

That sounds like a sensible and safe solution. The ceramic ceiling rose becomes simply cosmetic.

You still hook the wires over the hooks though, to give strain relief and support

 

[chuckey]

A suggestion :- replace one fixing screw with a length of BRASS studding, which goes right through the lathes/plasterboard. nut on underneath, washer and nut on top. lock your earth wires to the studding top and bottom with a pair of nuts and washers. It is important that the earth wires locking to the stud does not rely on the resilience of the ceiling material, as this may crumble, so leaving no pressure on the wire's fixings.
Frank

 

[Flyfisher]

Depends how bothered you are about t'Regulations, or whether you just want something that's safe.
I'm happy to use brass/ceramic switches, although in my latest installation I have for the first time earthed them. The fact that they're live when the tops are spun off, I don't care a hoot. Don't spin the tops off, then they're perfectly safe....

I wouldn't care a hoot either, in terms of my own safety, because I know not to spin off the tops of old switches and put my fingers on the exposed live terminals. I'm not so sure I'd be quite so unconcerned if there were inquisitive toddlers in the house though.

It could be argued that consumer unit RCDs should protect against fatal electric shocks in such circumstances, but I'd bet few of us would be prepared to use a youngster to test that assumption.

Still, I suppose it depends on their upbringing. FF junior was about 4 years old when he was 'helping' daddy fix some curtains tie-back hooks into the wall. This involved an electric drill and junior was keen to pay close attention to the operation, so he was close by when the drill went through a cable in the wall and made a huge flash-bang which made me jump and had junior in tears. No actual harm done, but we never had any problems with junior subsequently 'playing' with the switches and sockets around the house.
Could have been a coincidence of course. :wink: :lol:

 

[Penners]

FF junior was about 4 years old when he was 'helping' daddy fix some curtains tie-back hooks into the wall.

I applaud that, FF. It's always a good idea to ease the offspring gently into the idea of earning their place in the world. It reduces the shock of starting chimney interior work at the age of 8.

 

[Zebra]

No actual harm done, but we never had any problems with junior subsequently 'playing' with the switches and sockets around the house.

My Mum says I used to play with the sockets all the time when I was small. Now, finally, I'm officially allowed and she can't say anything about it so there!
I think all suggestions so far are sensible, although Chuckey's idea of using a nut and washer to secure the thing to the ceiling means you can't take it down easily when it's time for your 5 year test which of course everybody has done! Either solution suggested so far would do, I would think - drilling it out to run an earth wire through, or getting rid of the terminals and running the flex into a junction in the ceiling. I rather prefer the latter because it doesn't involve running unsheathed earth conductor into the fitting.

 

[Flyfisher]

FF junior was about 4 years old when he was 'helping' daddy fix some curtains tie-back hooks into the wall.

I applaud that, FF. It's always a good idea to ease the offspring gently into the idea of earning their place in the world. It reduces the shock of starting chimney interior work at the age of 8.

Eight? Are you going soft? :wink:

 

[Penners]

It's the damned Human Rights thing. Next thing you know, we'll be legally obliged to feed them. :evil: