2-way Switches confusing

[kazza24]

I have a problem with my hall and landing light switches.
(The old wiring system had a small red wire but I'm not sure what it was for). Downstairs is a two switch light fitting and upstairs landing is a one switch fitting. The downstairs light has two sets of wires supplying power to the switches, each wire carries one red and one black wire. The light fitting has two gangs labelled "Com" at the top and "L1" bottom left "L2" bottom right. I have tried to wire the switches as per the lighting diagram which came with the switches but I'm very confused. The downstairs is working using the right switch (for the hallway), red wire in "com" and black wire in "L1", as for the left switch (landing light) I can't get it working however I wire it. I need to wire it so that it can be switched on and off using the left switch (downstairs) and the upstairs switch. Can somebody please let me know how to wire these switches so both lights work.

 

[XtraRaptor]

Have you tried connecting up as they were originally?

 

[John D v2.0]

I have a problem with my hall and landing light switches.
(The old wiring system had a small red wire but I'm not sure what it was for). Downstairs is a two switch light fitting and upstairs landing is a one switch fitting. The downstairs light has two sets of wires supplying power to the switches, each wire carries one red and one black wire. The light fitting has two gangs labelled "Com" at the top and "L1" bottom left "L2" bottom right. I have tried to wire the switches as per the lighting diagram which came with the switches but I'm very confused. The downstairs is working using the right switch (for the hallway), red wire in "com" and black wire in "L1", as for the left switch (landing light) I can't get it working however I wire it. I need to wire it so that it can be switched on and off using the left switch (downstairs) and the upstairs switch. Can somebody please let me know how to wire these switches so both lights work.

For the downstairs light, you have one input connected to the mains and one output connected to the light. So that's simple enough.

For the upstairs, at one switch you have one input connected to the mains, and two outputs connected to the other switch. At the other switch, you have two inputs from the other switch, and one output to the light.

So you have to work out which two wires are connected to the upstairs switch L1 and L2, and connect them to the L1 and L2 on the downstairs switch, and then connect the remaining wire to the Com terminal.

don't forget to switch off the circuit... and good luck!

 

[securespark]

You need a multimeter to sort out which wire is which.

My guess is one will be the live feed and switch wire for the hall. The live feed goes to the C for the hall side of the switch plate, along with the "small red wire" and the other end of the small red wire goes to the
other C terminal. The other wire in this pair goes to the L1.

The other pair will probably be the strappers for the upstairs landing light.

These go in the L1 and L2 belonging to the Common terminal with one wire in.

However, you will need to confirm this using the multimeter.

 

[kazza24]

Hi, thanks for your advice. I've wired it up like you've both said (John & Securespark). I'm now able to turn the landing light on and off at the same point but unable to use it as a 2 way switch. I.e. I cannot turn it on downstairs and off upstairs. (I'm very grateful as at least I have light) I have an old switch upstairs tho so unsure if that has anything to do with it not working. Have uploaded this switch for you. Many thanks for your advice xx

 

[kazza24]

I think I can see where I've gone wrong after re-reading this. I will take another look after work tomorrow and get back to you if successful.