light switch for bathroom problems

[pgtips911]

i have changed over the old cover well we had plastering done
and its been hanging on with one screw
since the plasters got behind it etc

anyway the wires dropped off when i came to replace it
its earthed to the back box
but i am left with 2 red wires and 2 black wires

i have tested the wires and 1 of the red wires is live the other isnt
and the two black ones aint either

i have tried to wire it up
putting the 2 red wires too common
and putting the 2 black wires to l1 says 1 way on it
the rcd tripped
by the way we have an rcd upstairs in the cupboard and that tripped
i guess i am doing something wrong here, dont want to blow up my house lol

so i have at the moment got some wire blocks and put them on the 2 red wires esp the live one for now anyone help thanks

forgot to say the lights in the bathroom are low voltage spot lights the switch in on the landing

 

[EFLImpudence]

Were two of the wires in a connector separate from anything else?

 

[pgtips911]

hard to tell really as the wires at the back of the wall
looks like i have 2 sets of wires here for some reason
i just remember when the wires came off the switch the 2 black ones was joint together, i had to change the back box as it was not attached, and one of the screw holes had snapped ****y plasters who took it off. i say there is 2 cables there coming from where i dont know
i just pulled through what i took out

 

[flameport]

Two black wires joined together in a block.

The red wires to the switch, one in Common, the other in L1.

 

[pgtips911]

so put the live wire in common then
and the other red cable to l1 then(its says 1 way) that right
and like you say a block for the 2 black wires

 

[pgtips911]

is that right then guys??

 

[EFLImpudence]

Yes, that's it.

 

[pgtips911]

ill give it a try prob at weekend cheers