Help needed desperately with 3 gang light switch wiring

[Sam447]

This morning I have tried to replace a 3 gang 2 way switch. Before starting I drew a diagram of which wire went where and then disconnected everything. Then before I could connect the new switch, my darling husband has tidied up around me and disposed of my drawing!

I now have lots of wires and no idea where to put them.

The other problem I have is that when I had a new kitchen fitted, the incompetent fitter covered the alternative light switch with a cupboard so I am not able to identify which cable feeding in to the switch is the mains cable etc.

Below is a drawing of what I have to work with.

I can recall that the cable to the left if connected as shown powers one set of the lights (even though the blue wire is not connected). The two thick black wires are both live (checked already) everything else isn't.

Any help in how to do this would be really appreciated, especially as this is for my kitchen lights and I have a little one who will need feeding again soon!

lights

• Sam447
• 12 Apr 2014
• 1

 

[AndyPRK]

So the switch that is covered, was that a 3 gang or 1 gang ?

I assume none of these were joined at the back? Otherwise you wouldn't have disconnected them?

We're there more than 1 wire per terminal ?

 

[Sam447]

The switch that was covered was a 1 gang 2 way switch.

I think there were two terminals with more than one wire in, one in each of the sink and doors and a separate wire was used to connect that (sorry, may have been helpful to have put that in the first post!).

 

[AndyPRK]

Better try and find the paper then or get an electrician. Sorry.

Have lights stopped working in other downstairs rooms?

 

[Sam447]

OK, thanks for taking a look

 

[AndyPRK]

You could try taking a look at the lights and see what cables you have there

 

[viewer]

Andy is right; best approach is to use the light fittings as the starting point. Check continuity with all power off (i.e. which wire is which using multimeter and fastening each pair of wires in turn until you have a new diagram. A bit slow but will work; little one will enjoy adventure of dinner by torch light, but terminate all those ends before turning power on for the night.

 

[securespark]

Then before I could connect the new switch, my darling husband has tidied up around me and disposed of my drawing!

Note to self: dispose of husband if he does that again!

So, this three gang switch operated three separate groups of lights?

U/C lights, sink lights and door lights?

And the inaccessible switch?

You can remember which light this used to operate?

It looks like the spark/ kitchen fitter/ builder used three core cable for all the switch drops even if it was not required.

So, as you say, it appears from your initial work that the left hand cable uses red as a feed and yellow as a switch wire for the undercupboard lights.

Were there any link wires between the terminals?

The right hand cable is much newer, so it must be a later addition. That might give you a clue as to where this cable goes.

We have a good idea the left hand cable is not a two way (unless there is another switch for the U/C lights elsewhere?). If that is the case (that it is NOT two-way), the possibility is the other non-harmonised cable (ie red/blue/yellow cable) could be one way also. Are there any other switches for the other lights elsewhere?

When you say "the two thick black wires", you mean the ones you have shaded in black on your drawing?

IE, the red on the left hand cable and the brown on the right hand cable?

That there is no voltage showing at the middle cable suggests it is disconnected. Could this go to the concealed switch?

Assuming the lighting circuit is complete and the only disruption to the circuit is the removal of this one switch, have you tried connecting up the right hand cable's L1 and L2 (are both L1 and L2 conductors stripped back for connection to a terminal?) in turn to the live feeding the light fittings via a meter on the continuity setting to see if there is continuity?

 

[securespark]

Just another thought....how have you confirmed the two conductors you have shaded black in the drawing as "live"?