Replacing old 3 gang light switch Ask questions and find answers to many subjects relating to electrics and electrical work

[HowardG]

Hello.

I want to replace an old 3 gang light switch with a new one, and can't seem to work out the wiring positions as the two don't look alike.

Each of the switches operates a single light. There is no 2-way functionality required.

The old one has four terminals on the top row and five on the bottom.
They are as follows:

Four along top:

1. Labelled Common with brown wire
2. Labelled 1 way with grey wire
3. Labelled 2 Way with nothing
4. Labelled Common with brown wire

Five along bottom

1. Labelled 1 Way with black wire
2. Labelled 2 Way with nothing
3. Labelled Common with brown wire linked from top row #1.
4. Labelled 1 Way with blue sleeved with brown
5. Labelled 2 Way with nothing

The new one is nothing like this. It has three blocks, one for each switch.

Each of them have three terminals, 1 at the bottom, 2 and 3 at the top. 4th terminal position is blanked off in each block.

There is an earth terminal on the plate of the new switch.

Can you advise me as to the correct positioning of the wiring on the new switch? Thanks for any help you may be able to give.

[sparx]

Hi, basically you have 3 pairs of wires, the 3 lines in are in the terms marked Com. on old switch and equate to the 3 marked L1 on new one.
so you end up with the 3 brown cores along top row of new switch, keeping the link between the 2 as before (but now side by side.)
the 3 remaining cores go 1 in each of the L2 terms. in line with their original partners.
If you look at original swith you will see it's exactly the same set up except the centre 3 terms are upside down, or put another way,first switch and 3rd switch terms form triangles, middle switch is triangle standing on its apex.its just done to save space.
Sorry can't draw it but just take top & bottom wires from each switch in turn and fit to top and bottom of new one, plus link 2 browns as before,
get right two!!
regards SPARX

[HowardG]

Sparx,

You are da man!

Now all I need to do is decide how to repair the big hole in the Lath and Plaster wall I made when I tried to replace the single box with the double.

I am really not cut out for this!

[sparx]

HowardG ,
glad to help, nothin to this sparkin lark as a local builder assures me!!

[moggy1968]

grip fill and plaster mate!!

[Arandora]

Similar problem as the above so I hope someone can modify the answer for me.
I want to replace an existing 3 gang switch in my hall with a new one but the innards of the new one are different from the existing. The 3 switches control the hall light only; the landing light (from upstairs as well - so 2 way?); and the outside porch light.
Existing as follows:
At top
Common
Blue Yellow Blue Yellow

At bottom
L1 L3 L2 L1
Red Red Unwired |
+ -----------------| red wire plus short red wire link from L3 to right hand L1

New switch has three blocks, one for each switch.

Each of them has three terminals, 1 Common at the top, L1 and L2 at the bottom.

First, I presume this is the correct replacement switch, and if so, how do I rewire it please? :?:

Cheers :)

[Robpl1]

Similar wiring problem. See the image

. its a 3-gang front plate. Planning on replacing it with a touch switch on the 433 MHz spectrum to link in to my home automation system. New Switch has 4 connectors labelled L, L1, L2, L3 (

). Help on how to convert would be appreciated.

Best regards

Rob

[Mr White]

I can guess, but what do the manufacturer's instructions say?

[chriscba]

On the old switch, you have a feed wire going in to the first one.(the one with 2 reds in) then going into the second & then a yellow one into the third(should have had red sleeve on) get rid of the short yellow & red ones, all these are live feeds in.

now, the feed red cable that I mentioned above is to go into L.
the other three cables are to go into L1,L2,L3.

that's basically it, you may have to swap cables L1,L2,L3 around a bit to get the correct switching order.

If you look at the old switch, break it down into 3 parts, each with one terminal at the top & 2 at the bottom.