Two way lighting

Shaun007 · Joined: 14 Nov 2002 Posts: 2 Location: United Kingdom

Help please:

I've a single two way switch downstairs and a double two way upstairs. To operate the light, i have to switch the light on downstairs to operate it upstairs But if i dont switch on at the bottom it won't work at the top.
help it's driving me crackers.........

[Edited by Shaun007 on 14-11-2002 at 22:19 PM GMT]

Guest · Posted: Fri Nov 15, 2002 10:00 am

Two way switching requires two paths between the switches (I've tried to show this in a diagram)
If one of the paths fails, it means that one switch will only work if the other has been switched to the good path.
Fault could be the switch or the wiring between switches.
              DIAGRAM (sort of!)

  from                                         to
live feed     inter switch wire 1     lamp
             /--------------------------
----------/   inter switch wire 2 ----------
              --------------------------
        downtairs               upstairs
         switch                    switch

Hope this helps.

DEANO · Joined: 09 Nov 2002 Posts: 9 Location: United Kingdom

IF YOUVE DEFINATELY GOT A TWO WAY LIGHTING CIRCUIT AND BOTH SWITCHES ARE DEFINATELY TWO-WAY SWITCHES THEN IT SOUNDS LIKE THE BOTTOM SWITCH IS U/S. IT SOUNDS LIKE ONE LEG OF THE SWITCH IS NOT CONNECTING THROUGH. ITS ALSO WORTH CHECKING THAT ALL THREE WIRES IN THE BOTTOM SWITCH ARE MAKING GOOD CONTACT. TRY HAVING A LOOK AND IF YOUR STILL HAVING PROBLEMS GET BACK TO ME..........

Shaun007 · Joined: 14 Nov 2002 Posts: 2 Location: United Kingdom

I've checked the switch and connections both are fine.
I've noted the connections for both switches.
(both light-switches are the right way up)
downstairs :
Black at the top
Fat red core L1(pardon the description)
red.......... L2

upstairs :
Black: common
fat red core L1
red..........L2

just moved in property

I feel there isn't enough cable fed to both switches

Help anyone...........

DEANO · Joined: 09 Nov 2002 Posts: 9 Location: United Kingdom

IT SOUNDS TO ME THAT THE BOTTOM SWITCH IS THE PROBLEM. I THINK EITHER THE RED IN L1 OR THE RED IN L2 SHOULD BE THE COMMON. I SUSPECT ONE OF THESE IS THE LIVE SUPPLY IN OR THE LIVE SUPPLY OUT TO THE LAMP. THE TWO CORES THAT ARE IN THE SAME CABLE, I/E ONE BLACK AND A RED SHOULD BE THE TWO CORES OF THE TWO WAY CIRCUIT. THE OTHER RED SHOULD BE THE ONLY CORE IN ANOTHER CABLE USED AND THAT SHOULD GO TO THE COMMON CONNECTION. TRY ROTATING THE THREE CONNECTIONS IN THE BOTTOM SWITCH. AFTER A COUPLE OF TRYS YOU SHOULD OF CRACKED IT. DONT DISTURB THE UPSTAIRS SWITCH AT THIS POINT. LET ME KNOW HOW THINGS TURN OUT.

Guest · Posted: Tue Nov 19, 2002 2:33 pm

I've tried all combinations possible on the downstairs switch, still no joy.

I think I'll accept defeat on this one.

thanks for the information Deano

probably after xmas i'll call a sparky out

amtodd · Posted: Tue Nov 19, 2002 4:05 pm

I concur with Deano's first suggestion that the switch at the bottom may have failed. If it only outputs on one of the contacts, it will act as a one way switch and would give the same symptoms as you have.
Switches do fail.
I know you said the connections are fine, but do you mean you have checked the wires are secure in the terminals or did you test the internal workings of the switch via a meter (or both)?

If that is not the problem, I'd check the wires are not broken between the top and the bottom switches and the rose / junction box and the fitting.

Can check cables and switch with a multimeter (use some spare cable to extend the meter probes between the upstairs and downstairs). Don't forget to turn the power off!

kendor · Joined: 16 Mar 2004 Posts: 5066 Location: United Kingdom

To Convert from One way Lighting to Two Way the easiest and most common way is to use the Conversion Method.

Firstly Isolate the lighting circuit from the supply(goes without saying really)

Run a Three Core and Earth Flat cable from the existing switch to where you want the second switch

Remove existing switch and look at back of it if it has only two terminals then discard it if you are lucky and it has three marked C, L1 and L2 then you have one two way switch already

you need to obtain another two way switch

in the original switchbox you now have a two core (commonly a red and a black core, see below)

and the new three core cable ( red, yellow and blue cores)

connect the red from the three core to terminal C

As normal if the two core cable has red and black cores:

connect the red from the two core cable and the yellow from the three core cable together into terminal L1

connect the black core from the two core cable and the blue cable from the three core cable together into L2

If the two core cable cores are both red:

connect one to the yellow in L1 and the other to the blue in L2

at the other switchbox connect the red again to C

the yellow again to L1

and the blue again to L2

and that is it! you don't need to touch the wiring at the ceiling rose at all!

ban-all-sheds · Posted: Tue Mar 16, 2004 9:20 pm

Kendor -

1) Why did you beat yourself up trying to describe in words what is much easier explained with a picture? Like this one -

2) Why did you reply to a problem that is 17 months old?

breezer · Posted: Tue Mar 16, 2004 9:40 pm

i asked that too, but it has been "lost"

kendor · Joined: 16 Mar 2004 Posts: 5066 Location: United Kingdom

Just trying to help, why did you reply to a problem 17 months old then??

I thought i did a good job describing what to do step by step some people cant follow diagrams

and thirdly whats it to you if i decide to help someone Jealous??

breezer · Posted: Wed Mar 17, 2004 5:53 am

kendor wrote:

and thirdly whats it to you if i decide to help someone Jealous??

I shall explain.

if you look at origonal post it shows

Shaun007

Joined: 14 Nov 2002
Posts: 2

so that means not only is the post very old, Shaun007 only ever made 2 posts (both in same thread) which means he wont be back, which in turn means you had to find the post in order for you to reply to it,which was a total waste of time, but hopefully you will have learnt from this post to always read how old a post is before you reply.

jealous us, no.

kendor · Joined: 16 Mar 2004 Posts: 5066 Location: United Kingdom

sorry what i meant to say was mind your own business!

Big_Spark · Joined: 20 Feb 2004 Posts: 3434 Location: United Kingdom

kendor wrote:

sorry what i meant to say was mind your own business!

The voice of reason speaks, Kendor, with your charm, wit and obvious intelligence you should join the Diplomatic Service.....of some tin pot, third world dictator..

ban-all-sheds · Posted: Wed Mar 17, 2004 9:28 am

kendor wrote:

Just trying to help, why did you reply to a problem 17 months old then??

When did I do that? I was replying to you, and your post was less than 4 hours old...

Quote:

I thought i did a good job describing what to do step by step some people cant follow diagrams

You did do a good job describing it, but I would submit that if someone really can't follow diagrams (particularly that one, which I think is extremely clear) then they have no business doing wiring jobs.

Quote:

and thirdly whats it to you if i decide to help someone Jealous??

No - why on earth should I be jealous? It was mainly curiousity that prompted my second question, but it does also have something to do with me, and every other reader of the forum, in that it pointlessly dragged that old dead topic back into the current ones.

And if you're going to react like this when someone just asks you a question, I dread to think what you'll do when someone says "no, you're completely wrong"...