lightingwiring
I am replacing the light switches in my house. This one has thrown me a bit, as it is labelled differently to the others.
The new switch (a BG Electrical Nexus 812-01) is on the left and the old one (of unknown manufacture) is on the right.
How do I wire the new switch? Do I just put both 1 wires into L1 and both 2 wires into L2? Should I also put the brown wires into common?
1 white which is hot, and 2 greys which are hot...the switch is on 2 seperate breakers.
This means that:
new switch it only has 1 common hook up, then 3 other connectors on the otherside.
The new switch will NOT work here.
You cannot feed from "2 separate breakers" to "1 common hookup" - you need a different switch that more closely matches the old switches (which look to be 3 separate switches, each with its own connections.)
Managed to solve this myself with a live wire detector:
I believe the red/black on the far right of the diagram are wired incorrectly, as the black is live and the red neutral.
I believe this set up is described here, which states that it's not recommended for new installations for many reasons, but can be found in old homes.
Best Answer
Since there are 3 switches involved, you have a ...
You know, I don't know what to call it in the UK. In the US we call it 4-way, but the UK has different names for these things. Regardless, the schematic looks like this:
Switch designations are USA naming. Diagram's 3-way is your 2-way.
As you can see, the operating principle of multi-way switching is that one traveler is live, and the other is not. Each of the switches exchanges the travelers - which is pretty easy to do on the ends.
You have the pictured new switch. And I imagine you've been using that all day in 1-way (plain) and 2-way (US: 3-way) switches on the ends.
But the middle is special. Here, exchanging the travelers requires 4 terminals - 2 travelers in, and 2 travelers out. Obviously the 2-way switch you have is simply not up to the task.
You will need to obtain the correct switch for that position.