Change Light Switch Configuration


Postby danphillips1977 » Tue Apr 01, 2008 12:25 pm

Hi All,

Wonder if someone could help me.

I have two switches controlling one light (ceiling rose) in my living room.

I have just installed a set of low voltage down lights from B & Q and now need to wire these up. What I want to do is use one of the existing light switches to connect to the new down lights, whilst leaving the other remaining light switch operating the main light - as it does now

Under my floorboards, there appear to be two junction boxes connected to each light switch - with cable for the mains feed and what appears to be another cable running imbetween each junction box. Can anyone help me on how I go about doing this? If possible, I dont really want to replace any cables from the switches to the junction boxes or to the ceiling rose for the main light

Many Thanks,
Dan
danphillips1977
Rank: Labourer
Progress to next rank:
50%
Posts: 3
Joined: Tue Apr 01, 2008 12:18 pm

Sponsor

Simply Build It

Postby ericmark » Tue Apr 01, 2008 3:09 pm

I can only answer in general terms.
1. Normally the two way wiring goes from switch to switch and does not go to the light fitting.
2. Normally the ceiling rose acts as a junction box and no other junction boxes are used for the lights.
3. Where as original fitting extra low voltage lighting is used instead of using the ceiling roses as junction boxes the backing box for the switch is used instead.
4. Other electricians use junction boxes under floor boards where extra low voltage lighting is used. (There are objections in both cases but I will not expand now).
5. Two way switches normally use three core and earth instead of two core and earth.
6. Lighting cable is normally thiner than power cable.
Normally what you want can not be done, but since you say you have junction boxes maybe you don't have standard wiring and number 4 method has been used. If so than with power off if you look at cables if you find a red,yellow,blue or brown,black,grey cores i.e. three core and earth then you may be able to do as you wish but if red,black or brown,blue then most likely you can't. There is a project area and this will give you some idea as to normal methods of wiring.
Hope at least that gives some pointers?
ericmark

Postby danphillips1977 » Tue Apr 01, 2008 4:25 pm

Hi there. Thanks for the response. I think the link wire does go from switch to switch - so I could well be wrong re: the junction boxes

I have removed one switch (the second I beleive on the circuit) which contains one input cable with a Red, Black, Blue(or Brown cant remember which as at work at the mo) and an earth (4 all together - using old wiring colours as installed quite a few years ago) - the other switch now doesnt work which I guess confirms the switches are linked?

Can I disconnect the link cable from main switch (Im expecting to see two cables into that - being a mains and the other end of the link cable to the second switch) to the second switch whilst enabling that main switch to still function? If so, I think I can just come off one of the Junction boxes above to get power for the second switch connected to the down light transformer (using the cable described above)?

For the down light cable, I have 0.5mm Two core with no earth (instructions say the lights dont need to be earthed - just the transformer itself)
Thanks for your help,
Dan
danphillips1977
Rank: Labourer
Progress to next rank:
50%
Posts: 3
Joined: Tue Apr 01, 2008 12:18 pm

Postby ericmark » Tue Apr 01, 2008 7:35 pm

I am sorry I can't see what your question is.
ericmark

Postby danphillips1977 » Tue Apr 01, 2008 9:14 pm

Sorry - just re read what I put - completely confusing - any how, no matter as I've now managed to sort all this evening

What I've done - Removed link cable from main switch and re-wired that switch so the main living room light works now on that main switch only

Used cable from second switch to now run into a new junction box which I've installed that is all hooked up to the down lights

Thanks for your help and advice
danphillips1977
Rank: Labourer
Progress to next rank:
50%
Posts: 3
Joined: Tue Apr 01, 2008 12:18 pm

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