2-Gang Swtich 2 Lights Wiring Problem

[mp1london]

Can anyone help??

I have two light fittings in a bedroom, the wires come down to a single light switch. I have a Red, White, Black and Blue coloured wires.

The Red and White wires into Switch 1 control one of the lights fine. But I can't work out how to connect the Black and Blue wires to control the 2nd light.

The swtich is 2 gang so L1, N and 2-Way (twice).

When I touch the Black wire to the other switch the 2nd light works so I know its working, just not sure how to do it properly.

 

[holmslaw]

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[electronicsuk]

One set of wires to L1 and common (or 'N' as you call it, but it's not neutral) one one switch, the other set to L1 and common on the opposite switch. Exactly how these terminals are laid out depends on the manufacturer of the switch, but often one set is upside down relative to the switch next to it.

 

[mp1london]

Thanks for the quick repsonses:

A picture has been uploaded.

at: //www.diynot.com/network/mp1london/albums/5251

 

[electronicsuk]

Are you sure that black isn't a neutral? Did there used to be a short piece of wire linking the two common terminals on the old switch? I suspect the answer is yes.

 

[mp1london]

If I touch the Black Wire to the White Wire with the swtich on, the 2nd light comes on as well. But I want to control the 2nd light independately.

 

[electronicsuk]

If I touch the Black Wire to the White Wire with the swtich on, the 2nd light comes on as well. But I want to control the 2nd light independately.

But did there used to be a short link wire on the old switch?

I suspect you need to remove the red wire completely and put it into a spare piece of terminal block, and use a short length of wire to link the terminal with the black wire in it to the common next to it (in place of the red).

 

[mp1london]

The old switch was a double dimmer switch with a L1/L2 and C X 2.

No short wire was there. The 3-core wire is Red, Blue, White and the Black wire comes in seperately.

Thanks for your help.

 

[electronicsuk]

The old switch was a double dimmer switch with a L1/L2 and C X 2.

No short wire was there. The 3-core wire is Red, Blue, White and the Black wire comes in seperately.

Thanks for your help.

Well, unless linking the red and white together causes the light to come on, I can't see how it could have ever worked before without the link.

 

[mp1london]

At the moment. The switch which controls the red/white wires, works i.e. it controls one light when in the on position.

So do I need to get a small loop and link the white to the blue or black wire?

 

[ban-all-sheds]

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

 

[electronicsuk]

Sorry, I thought the red/white switch was the one not working.

In that case, if attaching black and blue together does not work, isolate blue in a terminal block and push it away to the rear of the backbox where it wont get caught by the accessory screws. Use a short piece of wire to link the terminal with the white wire to the terminal where the blue was previously.

 

[mp1london]

OK, got it that works, I got a short loop from the white to old blue and isolated the blue and both lights work now.

Many thanks for your time today.

Mike.

 

[Paul_C]

All seems a bit strange, red, white and blue cable has not been made for over 50 years.

Not quite that old - Red/white/blue was replaced with red/yellow/blue circa 1963/1964 (but even then, flexibles continued to use white for a few more years).

The presence of black as well poses a question in my mind of how that's run though. I have a feeling that if you look at where it disappears through the box that it might just be a single which somebody has pulled in later to provide the second light.

 

[holmslaw]

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