Ceiling rose/switch problem

[Goat74]

Hello,

first post on here ! I have just removed a ceiling rose as I removed the old light which had its own ceiling attachment. I've followed the wiring diagram and my new rose will not work, so I trawled through some post and tried some differant combinations as I was unsure which wire is the switch wire (Not marked). Eventually I figured that I could run my light with a working switch with only two wires but I can't see how that is possible ? I have now added the two non working wires into the middle block but it all works without them attached. Can anyone explain how it is working and is it dangerous ? Picture attached.

Coming from the ceiling I had one wire with a red and black and one with red/black/neutral. The switch it runs off is a 1 way switch with a red black and neutral and if I try a continuiity test with a multimeter then non of the wires make my multimeter beep when the switch is on.

 

[Johnmelad502]

//www.diynot.com/wiki/electrics:lighting:single_way_lighting

 

[Goat74]

I had a look at this earlier, I just can't figure out what the two spare wires are for ?

 

[Spark123]

Does the switch work?
Is there another light on the same switch which no longer works?
I can also only see one earth wire too

Ceiling rose

• Goat74
• 13 Dec 2009
• 1

 

[AndyPRK]

check to see if the light is other room are still working.

 

[Goat74]

Yep, all other lights appear to be unaffected. I put my multimeter on the two that seem to power the light and I get 240v when the switch is on and nothing off any wires when off, I would have thought that one of the wires would have given a permanent 240v ?

 

[Johnmelad502]

Looks like this is the last light on the circuit. You need first to establish which wires go to the switch. For this you will need a multimeter. Do you have one?

 

[Goat74]

Yep, I've tried attaching the multimeter to each set of wires in turn and flicking the switch to see it they would make the buzzer sounds but alas no (checked the switch on the wall and this test worked)

 

[Johnmelad502]

Do you have a picture of the back of the switch?

 

[Goat74]

No but I do remember it has two light switches on it and the one for this light has a COM with a red wire in and an L1 with a black wire if that helps ?

 

[333rocky333]

I have now added the two non working wires into the middle block but it all works without them attached.

Including switching on/off

If connected like the drawing and the light is constantly on
Then the red and black in the centre terminal are your switch pair.
they are in the wrong place.

Unless there is a second light, parelleled off that light.

 

[Goat74]

The switch works fine with just two wires I expected it to be on permanently ?

 

[333rocky333]

it may have been altered or 3 plated in a j/b somewhere, leaving just switchline and N at the light.

The other pair may have once been a second light or even a previous switch at some time.