Changing a 2 way light switch

[MelEMck]

Hello,

I’m in desperate need of some help. I went to change a 2 way light switch but the back of the two switches are so different.

When I’ve put the new one in, one switch is giving light to two lights, turning off one, or switching over to give light to living room or just kitchen.

Can any help help me in where to place the wires in the new switch?

I have added pics of the old switch (blue) and new one (grey). The picture of the new one is wired incorrectly!

Thank you

 

[blup]

Hello,

I’m in desperate need of some help. I went to change a 2 way light switch but the back of the two switches are so different.

When I’ve put the new one in, one switch is giving light to two lights, turning off one, or switching over to give light to living room or just kitchen.

Can any help help me in where to place the wires in the new switch?

I have added pics of the old switch (blue) and new one (grey). The picture of the new one is wired incorrectly!

Thank you

Did it work properly before you changed the switch?

 

[MelEMck]

Hi, yes it did.

I’ve moved the wires round and I have one side working fine. However the other side is now just permanently on!

 

[blup]

That short link wire takes power from one gang to the other. Have you worked out which wires link to the other switches?

 

[MelEMck]

At the moment, looking at the pictures, the right hand side is working as normal. However the left switch, is just permanently on.

 

[blup]

The right switch seems to be wired one way so presumably operates the living room switch?

 

[boringoldcodger]

the right hand side is working as normal. However the left switch, is just permanently on

I take it you mean the light controlled by terminals COM1 and L11 is working correctly. If so, I'd suggest swapping the long brown that's in COM2 with the one that's in L22.
Also, it looks to me that it's a metal faceplate so you must earth it using the earth terminal to the right.

 

[RandomGrinch]

It may be difficult to visualise, but your new switch is layed out in the same way as your old switch!
Your old switch however is 1 way, when your new one is 2 way.
Just imagine another couple of holes drilled out, and you get the same set of triangles, with common at the apex...

 

[MelEMck]

Would this mean that the com wire would be in on its own with no other wire?

 

[ericmark]

Except with electronic switches for two way switching you need at least three connections, and on/off two connections minimum in both cases one wire is permanent line so by borrowing the line from other switch you can get away with four wires, the old blue switch seems to link two wires, so in essence only three wires so can't get two way switching with only three wires.

This is the basic diagram for two way switching, there are other methods, but that method does not need a connector in the switch back box so is the preferred method.

 

[ericmark]

Would this mean that the com wire would be in on its own with no other wire?

In the two way switch yes, in the on/off switch no.

 

[MelEMck]

I’ve got this, and now it’s only the left hand side working as normal, and the right switch will switch that off too

 

[MelEMck]

Now I only have the left hand switch working…with the other set of lights permanent on still.

I have matched the old switch and cables but still not working for individual switches

 

[ericmark]

If one side is two way and the other side on/off then the link wire will only link terminals not to wires. And one would expect to see it in com with one switch of pair (the on/off) and L1 or L2 with other switch of pair.

I would if I was trying to sort it out start by marking each brown wire, then I can record my findings, I would likely put at least two into a block connector so I can test without danger, and job one is find the permanent line wire, so meter out and test, the permanent line can then go into the com on one switch with link to L1 on other switch, so now only left with 3 unknown wires.

So in turn put them in the L1 of the com switch, and find the one which switches the one wall lamp, then other two go in the L1 and L2 of two way lamp, does not matter which way around.

Also you need an earth link to the switch.

 

[EFLImpudence]