Replacing MultiWay Installation with Dimmer

[stinkymarshall]

Hi,

I'm new here so please tell me if i am asking really basic questions!

I have a 2 switch light switch downstairs. one switch turns the lounge light on and off, the other switch controls the landing light upstairs.
i have a switch upstairs which also controls the landing light.

i have tried to replace the downstairs switch with a set of 2 dimmers.
the old switch had three connections - live, neutral and common. when i disconnected it there were two wires for each (red and black) going into the wall and one 'loose' wire which was connecting live to common (i think!)

the new 2 gang 2 way dimmer switch i've bought also has 3 - live neutral and SW. i'm not sure what SW means and the instructions are really confusing.

I've managed to connect the downstairs light and that works fine. the switch which controls the landing light i just cannot get to work. live and neutral are connected up, i just don't know how to connect the SW bit up.
i tried connecting live to sw with the 'loose' wire but it made no difference.

someone please help! have i bought the wrong type of switch or do i just connect ?

thanks

 

[ELZ4742]

SW = switch wire
COM tends to mean permenant live

are u sure its neutral? dont see how that could be.

 

[stinkymarshall]

no i;m not sure it's neutral. i just assumed it was cos it's black.
apologies, i'm a complete novice

;;;;;;;;;;;;;; ;;;;;;;;;;;;;;;
; ; ; ;
; L SW X ; ; L SW X ;
; ; ; ;
; ; ; ;
;;;;;;;;;;;;;; ;;;;;;;;;;;;;;;

This is what my 2 gang 2 way switch looks like. The 'x's are funny sybols which i believe are used to show dimming.
I have a total of 2 red and 2 black wires coming in from the wall and one connecting wire which is red.
i have connected the normal switch up by using one of the red and black wires but cannot work out which way to connect the other two - i have two wires left and three connection points!

 

[ELZ4742]

its a real pain init

weird labelling, however, the
IMO
L will be the common,
SW - switch
X 2way

could u upload a pic of the wirrin? its a job to see what u have.

 

[stinkymarshall]

don't think you can upload pictures here can you?

it's basically 4 wires coming out of the wall, 2 of which are used and two of which aren't.
someone was telling me i need a retractive switch or something!?[/img]

 

[Steve]

don't think you can upload pictures here can you?

it's basically 4 wires coming out of the wall, 2 of which are used and two of which aren't.
someone was telling me i need a retractive switch or something!?[/img]

Go to www.imageshack.us and upload your pictures, copy the links here. Post a scan/high res picture of the instructions too. Do the instructions mention anything about a slave dimmer?


However, after a quick think, I reckon one red/black is the switch drop from the downstairs light. This would connect (i presume) to the L and SW terminals of one switch, or whatever the instructions say for standard 1-way switching.

The red link wire you have would be to carry the red live from that switch to the red live for the other switch. Then the other red and black are the strappers carrying the switched live feed to the upstairs switch. This would only work with one lighting circuit (or else borrowing neutrals from the upstairs circuit)

 

[ELZ4742]

but that wouldnt work though, if the perm feed is used from the other switch to feed the com, the landing will switch on and off from down stirs but wont from upstairs.

the common upstairs needs to be perment and i cant see how it could be........

my brain hurts......

 

[Steve]

No, carry the live feed for the downstairs light over to the second switch downstairs, on the COM. Then L1 and L2 used for strappers to the upstairs switch, and single red from upstairs switch to the upstairs light.

 

[ELZ4742]

but i cant see how that would work.

unless both commons up and down are connected to each other i cant see how it would wrk?

 

[ELZ4742]

sorry dude, got my wires crossed

 

[Steve]

Edited - while i was typing ELZ... posted that picture clearing up his misunderstanding

 

[ELZ4742]

phew, got there just in time

 

[Steve]

so the OP has wiring like this:



But he just needs to find out what his terminal markings mean.