2 gang 1 way lighting query

[pinotnoir]

I have a dining room with a (working) ceiling light. Recent decorating has exposed wiring for a couple of wall lights previously hidden behind the wallpaper and I'd to get these working as well. There appears to be standard 2 core + earth cable coming down to both of the wall lights. There's only 1 switch in the room which has a dimmer on it. There are 4 cables coming to this switch - 1 earth, 1 red and 1 black - which are attached to the existing dimmer. There's also a second red cable which is currently doing nothing. If I want to replace the existing 1 way 1 gang dimmer with a 2 gang dimmer how should it be wired up? Am I missing a cable as I've only got 1 red cable spare Thanks in advance.

 

[fireman22]

well as long as the cables havent been removed elsewhere, you change to a two gang dimmer wiring centre light switch as before C & L1, put a small link of cable between C & C terminals and single red on to the L1 terminal of the second wall light switch. the only problem you might have is the cable that goes into the first C terminal must be the permenant live feed so if it doesnt work first time you may have to swap wires in C & L1 in centre light switch

 

[securespark]

The feeds to the wall lights, if they are not switched from the wall, may well be permanent live intended for fittings with integral switches.

 

[pinotnoir]

Thanks to you both for the suggestions.

I've wired things up as fireman suggested i.e.:

red and black cables from previous working ceiling light to L1 and C respectively of dimmer 1

jumper cable between dimmer 1 C and dimmer 2 C

2nd red cable (previously unused) to dimmer 2 L1

Now when I switch on dimmer 1 BOTH the ceiling and wall lights come on
Dimmer 2 does nothing

Does this mean I have to follow fireman's suggestion of swapping L1 and C on dimmer 1 (ceiling light)??

Thanks.

 

[fireman22]

hi if you take out the cables in dimmer 2 when you switch on dimmer 1 do they all still light together?

 

[pinotnoir]

Hi fireman

If I've understood you correctly you're asking me to disconnect L1 and C on dimmer 2 and check dimmer 1 - in this case only the ceiling light comes on and not the wall lights.

 

[fireman22]

have you done it, taken the wires out i mean

 

[pinotnoir]

Hi, yep, with no wires going into dimmer 2 then only the ceiling light comes on when I switch on dimmer 1 (no wall lights)

cheers

 

[fireman22]

right then if you connect it as before it should work, but if dimmer 1 needs to be on for dimmer 2 to work you will have to swap C & L1 wires in dimmer 1, must leave the link in between C terminals, (nearly there)

 

[pinotnoir]

bingo!

all sorted

you're a star!

 

[fireman22]

happy to help, just noticed nearly 100 views but no help, oh well.