Help please with light wiring

[ccaadse]

Hi all,
I have just bought a new ceiling light from ikea and i went about fitting it , and i first took off my light and celing rose , i had two black wires and two red ones, no earth (house is quite old) i put them in a connector thing (the two blacks together , the two reds together) so i have now one brown wire for my reds and one blue for my blacks, but when i connect them to my light , the light stays on but it wont turn off ! PLEASE HELP !

PS i dont understand any electrical jargon so please keep it simple!

All help appreciated.

 

[ZenStalinist]

What you're doing is you're connecting it at the light... Most lighting uses a loop system, but you're somehow connecting the loop and live together at the light rather than the switch completing the circuit.

See the sticky topic entitled 'For Reference'.

 

[ccaadse]

Thanks for replying but i dont know what your talking about if im honest. Lets simplfy it , i have a two black wires and two red ones , my light wont switch off. How do i wire it ???

 

[ZenStalinist]

I think then I know your situation... These two black wires you speak of... one should be tagged with red. There should be three blocks for you to place the wires in called 'neutral', 'loop' and 'live'

Black wire from switch (often has a red tag) should be wired into 'live', red wires should be wired into 'loop', and other black wires should be wired into 'neutral'. Sometimes other names are used. This diagram should help:

By the sound of it two things differ here:

1. you don't have wires going to the next light, your light is at the end of the circuit

2. There is no Earth, which I believe you already mentioned.

 

[ccaadse]

thanks for your help , ill go a try it.

 

[securespark]

I can see where you're coming from, but if that were the case (end of run) then surely the fuse would blow if the reds and blacks were wired together? Because the two blacks would be switched live and neutral in the same block. UNLESS the switch is OFF, in which case it would not short.


Before you proceed you need to make sure the fitting you are connecting to an unearthed lighting circuit is Double Insulated (requires no earth) with the symbol of a square within a square on it somewhere.

The above is MOST IMPORTANT!

You need to carefully ascertain with a multimeter which cable is which. With the power off, attach the meter to each pair with the setting on continuity, and the switch on.

The pair that buzz are the switch pair. Double check this by switching the switch off, the buzz should cease. Mark this black with red tape or sleeving.

Then, as described by Zen, the reds go together in a terminal but not to anything else, the black marked with red is the switched live goes to L on fitting and the remaining core (black) is neutral to N on fitting.