Bathroom pull-cord switch (yet again)

[MRH]

Hi,

Apologies for asking a question very similar to several already on here - but I can't find one that matches my query exactly as I seem to have additional wires.
I am replacing a bathroom pull-cord switch - unfortunately I don't have a record of how the wires were connected previously (I've learnt that lesson now).
I have 5 wires - 2xred, 2xblack and a green-yellow earth wire. There are 2 lights but they are on the same switch (i.e. both go on/off together).
The new switch has three ports - L1,L2 and COMMON - please advice where I should connect each wire - many thanks.

Mike

 

[Spark123]

Are you sure there is only one earth wire, there should be two as it sounds like there are two cables, possibly two earth wires in the same sleeve? Were the two blacks jointed together in a piece of terminal block? If so, joint both blacks back together, one red to Common and the other to L1, and earths to the earth terminal.

 

[MRH]

95% sure there is only one earth wire.

The two blacks were joined together.

So, one red to Common, one red to L1, nothing to L2, and the two blacks together but not through any terminal on the switch? Is that right?

Thanks - your help is MUCH appreciated.

Mike

 

[Qedelec]

That's right.
If you are right in only one earth, then it needs investigating.
A lost earth is as bad as no earth at all. In fact its a lot worse, as someone could fit a class I fitting thinking the earth is intact.

 

[MRH]

OK - many thanks - will investigate the missing earth.
Mike

 

[MRH]

Many thanks - all working fine now. I found the missing second earth wire with a bit of poking around.
Mike

 

[Qedelec]

Mike for safety's sake, it is best to check the continuity of Circuit Protective Conductors (earth) after all work is carried out. This is also a requirment of BS7671.
If I had a pound for every time I have found broken earth paths, I would be a very rich bunny.