double light switch wiring problem

27 Jan 2014
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United Kingdom
I have been trying to swap over new light switches for old light switches around the house. Most have been a simple switchover however I have one light switch which feeds two separate light fittings in the same room. I want to replace the single switch with a double switch on there to switch on/off each light fitting independently.

The problem I am having is on the single switch one of the red wires goes to the common, the other red wire goes to L1 and the two black wires are in a choc bloc together.

In trying to put in the double switch, I have tried putting the two red wires into two separate commons and the adjoining black wires into separate L1's as that configuration works on other double light switches in the house but this has blown the fuse.

I have tried other configurations with the red and black wires but can't seem to get it to work.

How should these wires be configured?

Any help would be appreciated.
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you can't just control 2 lights seperatly like that.

Those lights are wired differently to your other lights in your house

The neutral goes into the switch back box.

Leave the two blacks joined in the back as they were.

And the reds to the switch
In doing what you have you have created a short circuit which is what blew the fuse. The blacks were looped at the switch and are neutrals. The only way to operate the lights independently is to run a new cable from the second light in the circuit to the switch which will create a mess i would imagine. In your other switches you have a live supply and a switch live to the lights and the black should have a red/brown sleeve on.
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You second light does not have a direct feed from the switch, the two lights a linked across each other not at the switch.

You likely have this set up
To switch them in separately you will need to bring a single switch cable between the second light and the two gang switch and disconnect the switch live between the two fittings or this could be connected between switch and the first light, disconnecting the switch live at the first fitting and connecting to the new cable but not connected across the first light.

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