James wrote:
Hi,

I am no electrician but I thought I had a average understanding of circuits
until now!

When I moved into my house I had two outside lights, on the same circuit,
controlled by two switches, that turned both lights on or off. I got an
electrician to add another outside light, the supply was taken from one of
the existing lights.

Now I decided to add a fourth light myself. I took the supply from the same
light as the electrician did for the other, and now three of the four lights
don't work.

The garage light is the only one that works now.

My understanding of the evolvment of my outside lights can be seen here.
Sorry about the bad diagrams and web site, I did it in 2 minutes.

http://www.geocities.com/thunder_tan...idelights.html


The back door light had some terminal thing in it, with two black neutral
wires, two earths and one red live. When I opened this up, there was an
orange wire loose, it could have come out when I opened it, not knowing what
it was I did not reconnect it. The red live and one black neutral go to the
electrician fitted light.
It may seem obvious that the orange wire is the main's live wire and that is
why the 3 lights don't work. However I am confused by the fact that it is
orange and am not sure if I should connect it.

a) I *think* this work falls under Part P. If you don't know what that
is, just google.

b) Did you connect the orange wire to a spare terminal, or did you just
leave it loose? If the latter, you've got a potentially live wire waving
around in the breeze. Which is a Bad Thing.

c) Sounds like you have two twin core+earth cables connecting to
backdoor light, yet your diagram shows three connections. So I'm
guessing that the TC+E with orange connects to either the garage switch
or the back door switch, and then there's another cable running between
the two switches forming a 2-way setup.

You need to find out exactly how your circuit is setup and understand
how it works. A voltmeter can help you here [1] You can't rely on
guesses from this newsgroup (though they might help you understand what
you've got) because there's no guarantee that whoever put the original
wiring in did it in a standard way.

You might want to get someone competent to take a look at what you're
doing, as there are other things you can get wrong here. For example, if
those three outside lights are halogen lights with a 500W bulb in each,
and they're powered off a standard 5A circuit (which is what it looks
like from your diagram), then you're overloading the circuit.

Ben