I am in the UK (240v system).
I have a two gang light switch in my new house. Each switch controls a separate light, and it is the only switch which controls each light (one way switches). I want to replace the switch, so I unscrewed it from the wall and I don't understand how it is currently wired.
I expected each switch to be wired individually: the hot (brown) wire to the live (common) terminal, the neutral (blue) wire to the L1 terminal, and no ground (the switch is plastic). This is how the equivalent single switch is wired in the house.
What I found is that the the back box contains two neutral wires connected together with a terminal block, but not attached to the switch, and four brown wires. The first brown wire enters the live terminal on switch 1 and the second brown wire enters the live terminal on switch 2. The third brown wire is connected to L1 on switch 1, and the fourth brown wire is connected to L1 on switch 2. There is a bridge wire connecting the third and fourth brown wires, so they are always on the same circuit and the L1s are connected on both switches.
How does this work, and why are the neutral (blue) wires not attached to the switch at all?