> Wiring switch back into lighting circuit!?

Wiring switch back into lighting circuit!?

Posted at: 2015-01-07 
I imagine you have in the 3 grey cables, live loop, switched live and neutral loop.

Also imagine the unsheathed yellow cable is your earth.

The diagram "Don" has supplied is for each light to be separately controlled by it's own switch.

If you have 4 lights controlled by 1 single switch, the switch wire will be looped light to light along with the live and neutral loops. The yellow will probably be the earth

The fittings only use the switched live and neutral, + earth if required.

Establish at the switch which is live and switchwire. If colour coded you can follow the colours light to light.

If not you will need to "Bell" them out. Disconnect ALL wires and check them end to end with ohm meter or battery and lamp, marking each as you go.

(You can use the earth wire as your return in testing).

ON the good side, at least it doesn't appear to be 2 way switching, then you would have BIG problems.

I'm only sorry I can't help much more.

As an electrician, I know trying to explain a circuit in words is very difficult.

I assume that you want to control all the lights from a single switch, in which case my first suspicion is that the original wiring was a bodge. Possibly the original idea was to control the set of 3 fittings from one or more switches separate from the switch for the original light. In any case you now have far too many conductors for your purpose (I am assuming that your cables each have 3 or even 4 conductors).

To get this back in order, you need to trace the beginning and end of each cable:

1. Turn off the electricity at the fuse box.

2. Get pencil and paper ready to keep notes.

3. Disconnect all light fittings and attach terminal blocks to all the loose wires. Detach the switch from the wall.

4. Find another cable of suitable length, attach the conductors to each exposed cable in turn and bring the other end back to the vicinity of the switch, where you can use a multimeter set to ohms to find out where the switch lines actually go. One of them should, of course, have gone back to the fuseboard, but from your description that does not appear to be the case.

5. Repeat the process for the other cable ends, and you should eventually determine that one cable (3 or 4 conductors) has no match in the room, implying that that is the supply from the fuseboard. By now each of the other cables should be identifiable by a label at each end.

6. Confirm the fuseboard connection by switching on at the board and testing the exposed conductor with an electrical screwdriver. Switch OFF again.

7. Working from your notes, link the live supply from the fuseboard to one side of the switch via a post in each rose. You may not need to pass though all the roses. At the same time link the neutral supply and the earth by the same route. You now have 3 of the 4 posts in each rose occupied.

8. The other side of the switch is now connected to the spare post of each rose. This is then the switched post. If one rose is not in the path of the live line, remember to make return and earth connections to that rose as well.

9. There will be unused conductors, including the yellow ones. Protect the ends (e.g. cut the exposed copper off and tape the ends). Reconnect the lighting fixtures to the switched and neutral posts, possibly to the earth post as well.

10. Test. Good luck.

thanks for your help so far, ive had no success but ill try and elaborate on the system a bit more. Of the 3 additional fittings, one was previously taped up and tidied away with no (intentional) connections made, whilst the switch was still functional, the fitting only had 1 supply cable, as does the main working light which is not turning off with the switch.

does this suggest their are two lights on the main circuit and two on the rose? If so was the circuit maintained by the additional loop, as the 2nd main circuit light had been disconnected?

thanks again

You've fuscked that up good & proper.

You also described it dreadfully.

The wall lights each have 3 grey wires each containing 3 wires and earth?

(which ain't live,neutral,yellow & earth It's red,blue,yellow, earth)

is there just one switch on the wall for the whole room or can it be switched from 2 positions?

How many rockers are at the wall switch(es)?

Three cables on the ceiling rose:

= supply to rose + switched live + loop to next rose.

Two cables on ceiling rose either:

(a) supply to last rose on "spur" + switched live

(i.e. no loop required because nothing else left to feed); or

(b) supply to rose + loop to next rose.

(i.e. no switched live e.g if rose and switch "redundant" and original switched live has been removed, or rose intended for permanently on lamp e.g. security lamp / night light / fire exit lamp )

If switch does not turn off a particular lamp, pay particular attention to the live and switched connections in that particular rose.

Hope this diagram helps you sort it out.



sounds to me like you took the two lights that stay hot and added the switch light to their system. I would undo my setup and let all wires hang and fine the wire to the switch and mark it with tape.

Hi there, I believe this will have a simple solution, I am as of yet unable to identify it :) I aplogise for the long winded explanation! Will try to include as much information as necessary

Basically in tidying disconnecting the extra sockets up into the ceiling I have stopped the switch from working.

In the room there are 4 light sockets, the 1 main is(was) functional on the light switch. The other three fittings were assumed additional being closely together on the opposite side of the room and each with 3 supply cables, where the main fitting has 2 supply cables.

the 3 additional fittings are each supplied with 3 (grey) cables containing live earth neutral and a yellow cable (switch?)

Having removed the wiring from the fittings (and of course not taking note of how it was wired ;) ) reconnected the lives together (one red from each of three supplies) and neutrals (2 of the 3 which were exposed). This made the main fitting work again however the switch appears to have been removed from the circuit and will not turn off at the wall. Currently it can only be turned off at the fusebox and the switch does not turn it off.

Only one of the yellow wires appears to be unsheathed at each connection so I am at a loss as to reconnect it! Any help would be appreciated and can provide pics if helpful :P

Thanks for reading