DIY Doctor

Main navigation

very confusing ceiling wiring in old house

Postby shellc » Fri Jun 06, 2008 6:44 pm

please HELP :x
I am having problems with fitting a new ceiling light.
The problem is it only has 3 wires from the ceiling and there all grey with red on the inside (exactley the same)
does anyone know why or how i find out what goes where, my husband dismantled it and did not check where he undid them from.
Rank: Labourer
Progress to next rank:
Posts: 1
Joined: Fri Jun 06, 2008 6:35 pm


Simply Build It

Postby ericmark » Fri Jun 06, 2008 9:11 pm

It is common for the DIY enthusiast to make errors when changing light fittings. As a result I have made this standard reply I am tired of saying the same thing over and over again. What seems the problem is they don't expect the light to be feed with two wires the same colour (although one may have a bit of tape or sleeving on) neither do they expect the wires coloured in the Line (Phase) colour not to go to the lamp. Once they realise their mistake connecting earths (Green/yellow or bare) and permanent Lines (Red or Brown) together is not a problem but then they have three wires (Black or Blue) of which two are neutral and one is switched line. With luck the tape or sleeving is still on the switch line but if not there is a problem. Leaving one wire disconnected and trial and error finding the live and neutral pair is not to hard then the remaining wire needs pairing with one of the other two. Again trial and error will work as if connected to wrong on the next light in chain will not work correctly.
So to recap on the black or blue wires first mark each wire so you don't get them mixed up again. Bits of tape or correction fluid lets call them 1, 2, and 3. Connect 1 and 2 to lamp if it works great if not try 1 and 3 if it works great if not try 2 and 3. This leaves one wire over I will call it A and the connected wires B and C. So to get next lamp working try A with B if works great if not try A with C.
If there are any extra wires tough call in an electrician this often happens in bathrooms where there is also a fan connected if only two then great does not matter if the two blacks or blues are wrong way around it will still work.
If it still did not work call an electrician I have covered the common way if it has not been followed then tough sorry. Remember to turn off electric between each test and at the mains the switch on the wall will not isolate the ceiling rose. Also looking at projects can also help and taking photos is a good idea before starting any job so if you do miss marking a wire you do stand some chance of working out where it went.
All best Eric

Display posts from previous
Sort by
Order by

  • DIY How to Project Guides
  • DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!

  • Related Topics