Dimmer Question

[Skaz]

I would be very grateful if you could please help me with an electrical query.

I have a long narrow lounge with 2 ceiling lights, one light at either end of the lounge. As I come into the lounge from the hall there is a single gang on/off switch that controls the ceiling light at the near end of the lounge. At the middle of the lounge there is a double switch, one of the switches controls the ceiling light at the far end of the lounge and other switch is a second on/off switch for the ceiling light at the near end of the lounge.

My wife wanted to be able to control the brightness of both the lounge ceiling lights so I replaced the double light switch half way down the lounge with a double dimmer which works well as I can switch both sets of ceiling lights on and off and control their brightness from the dimmer.

However the single on/off switch that used to control the lights at the near end of the lounge now has no effect ie if the light at the near end of the lounge is on it remains on or if its off it will remain off regardless of what I do with the single switch.

I have read that if I put a dimmer into the circuit then the single gang switch must be a 3 way switch, I am not sure if the single switch that I already have is a 3 way or not, there are 3 connections on the back of the switch connected as follows:

L1 (also marked COM) with a red wire connected to it.
L2 with a black lead with red band and a blue lead with a red band connected to it.
L3 with a red lead and a yellow lead with a red band connected to it.

I would like to be able to switch the ceiling light at the near end of the lounge on and off with the single switch and control the brightness from the dimmer half way down the lounge but I am stuck as to how to achieve this.

Any advice that you can offer would be gratefully appreciated.

 

[EFLImpudence]

Firstly, you have been looking at American sites. They call the switches 3-way because they have three terminals.
We call them 2-way because they have two switching positions. This is what you have.

Anyway, to do what you want you need 2-way dimmers.
Perhaps you have but have wired it incorrectly.

Post a picture of your dimmer connections and wiring.

 

[EFLImpudence]

This is what you have and you have put the dimmer at the left switch.

 

[Skaz]

Thank-you for the information. The single gang switch is wired as described in my original post. The dimmer switch which controls the light also controlled by the single gang switch is connected as follows:

C-Red wire
L1- Blue with red band wire
L2- Yellow with red band wire
This is how the original switch that the dimmer replaced was connected.

The dimmer that controls the ceiling light at the other end of the room is connected as follows:

C-Red wire
L1-Black with red band wire
Again this is how the original double gang switch that the dimmer replaced was connected.

 

[EFLImpudence]

That all looks correct, so I can't say why it is not working properly.

 

[EFLImpudence]

Edit - deleted; I don't think what I wrote was correct.

 

[flameport]

Assuming the information provided so far is correct, the only possible fault is that the single switch is busted.

Any loose wires or wrong connections would result in the dimmer not working properly.

 

[ericmark]

There are a number of ways to wire dimmer switches, one method is to use three core and earth to switch and either use ceiling rose as junction box or fit a junction box. But however it is done non electronic switches need three connections on both switches. Your only listing two wires to second switch this can't work.

EFLImpudence has shown how normally wired.

This is what you have and you have put the dimmer at the left switch.

The red centre wire with standard switches goes to Com and with electronic to S you need a master and slave to use S can't use a standard switch.

There are some specials with electronic switches which will work with two wires, so with electronic you must read the instructions, they are not all the same.

 

[Skaz]

Thank-you all for your help but I have managed to figure it out. The two red wires in the dimmer were cross connected. I swapped them over and all now works fine.