'Sparkys' help required!!!

[Rolyan]

I am replacing a three gang rocker, with a three gang dimmer. Should be easy, because.......

The first is 2 way, so has 3 wires, a common, an L1 and an L2.
The second is 1 way, so has 2 wires, a common, and an L2.
the third is 1 way, so has 2 wires, a common and an L2.

Easy so far, BUT.....

There is also another wire. Its a short piece, that links from the first common, into the second common, then into the third common!!! Thats all it does! It starts at the first common, goes into the second, then comes out again and ends at the last!!!!

I can't understand what this does. If each switch wire comes down the wire, then through the switch and back up, what on earth is the small wire doing linking all the commons together. Is it needed, and why is it there.

The house is old, and has multiple protective earthing, but I can't see that it should affect this switch. Do I try and remove the piece of wire, and see what happens, or do I just panic, and call in an electrician. All my other replacements have gone fine (with a little help from Breezer) but now I'm stumped.

Any help appreciated.

 

[breezer]

I should assume that the new dimmer switch you have is 3 x 2 way, so i would suggest you connect it the same way as your existing switch, since the one you have is working fine

I would also guess that the link wire is actually a live feed

 

[MANDATE]

If you think about it, when you have already installed a lighting circuit and you want another, the general rule was to take a wire from the live side of a switch, this in the days before ceiling roses became ceiling roses incorporating a junction box.
A live wire will feed one switch, then the link will provide the live to the others.
Today three lights would have three switch cables from three ceilng roses, each switch would have its own live input and switched live output
On a one way circuit the live input would be to the common terminal but not necessarily so on a two way