On Mar 24, 2:10*pm, Luke wrote:
Hi,
I'm rewiring at the moment and have come across this system of wiring
up two lights, the first with one-way switching and the second with
two-way switching:

http://i598.photobucket.com/albums/t...es/circuit.jpg

Hopefully you can make out how it works from the circuit diagram!

Essentially the one-way light is fed from three core and earth, with
the third core used as the switched live for the second (two-way)
light. The Live for both lights is shared at the twin switch, by means
of a "jumper cable" whic I hope is clear in the picture. I *think* it
was done this way to save disturbing decoration as it would have
impossible to squeeze 2 twin and earths and 1 three core and earth
down to the twin switch, in the usual fashion. As you can see, the
system illustrated relies on just 2 three core and earths to the twin
switch instead.

My causes for concern a
A: One three core and earth cable is acting as the switched live for
two DIFFERENT luminaires.
B: The switched live for Light A is joined together with a crimp
connector within the ceiling rose for Light B.

Is this setup perfectly acceptable? If so, I will simply ignore,
otherwise I will cut out a new chase to accommodate the more standard
switching practice.

Thanks in advance

Luke

What you have here is the standard method of converting a one way
switched light into a two way.
The one way switch is removed & discarded.
A bit of three-core wire is run from this wsitch postiion to the
additional position.
The commons on the switches are link by one core.
The other two terminals (L1&L2 /"strappers") in the two switches are
linked by the remaining two cores.
The wires that fed te original one way switch are connected toL1&L2
terminals on the switch that replaced the one way switch.
Finish.