Fitting new light fitting

[davemccall]

just moved into new house and trying to fit lights. Changed many lights but this one has me stumped.
Light is controlled by two switches and cables in the ceiling are as below.
Cable 1-1 brown wire, 1 blue wire and earth
cable 2-2 red wires and earth
cable 3-1 red wire and earth

 

[ban-all-sheds]

What happens when you take the conductors from the L/N/E terminals of the old light and put them in the L/N/E terminals of the new light?

 

[davemccall]

Wires left hanging from ceiling so not able to compare with the old light.

 

[ban-all-sheds]

That is an unfortunate situation to be in. Because of it you now basically have to choose between Plan A and Plan B.

PLAN A:

• Learn how lighting circuits are wired.
  • //www.diynot.com/wiki/Electrics:Lighting
  • http://wiki.diyfaq.org.uk/index.php/House_Wiring_for_Beginners#Lighting
    
  • http://www.google.co.uk/search?q=uk+lighting+wiring+(basics+OR+101)
  • //www.diynot.com/wiki/Electrics:books
  • //www.diynot.com/wiki/Electrics:index
• Get a multimeter and learn how to use it.
• Identify which conductors are which at the switches and the light positions.
• Work out what should go where and connect everything up properly.

PLAN B:

• Get an electrician.

There are some irresponsible people here who will tell you that there is a Plan C, which is to start trying different things without really knowing what's going on, hoping to get it working by luck, or by blindly following instructions to put-this-wire-in-that-hole without any idea as to why. Please don't listen to them - you must know what, and truly understand what, you are doing.

Electrical-installation-by-guesswork is a foolish idea.

There is no Plan C for anybody sensible

 

[JohnW2]

The OP may have inherited the 'wires hanging from ceiling', rather than have created that situation himself.

 

[ban-all-sheds]

Indeed, he may have done. I should reword my reply.

If that is what happened he should make a formal complaint to the vendor, unless he bought it like that, as they were not supposed to remove the lights, and could probably be held liable for the costs of replacing them.

 

[JohnW2]

Depends on contract.

 

[flameport]

Depends on contract.

Doubtful that any contract which permitted persons to leave bare wires hanging from a ceiling would be considered valid.

 

[JohnW2]

Doubtful that any contract which permitted persons to leave bare wires hanging from a ceiling would be considered valid.

That is probably true. The standard conveyancing forms certainly have provision for light fittings to be excluded from the house sale, but (as you can see here), also require that removed light fittings "should be made good" - which I presume probably includes making things electrically safe! ....

Kind Regards, John

 

[ericmark]

As said some testing will be required. There are a number of methods and options used to wire lighting, it could have loop to switches, or loop to lamps, and lamp could be mid way or end of run, but what ever method used we expect to see between 1 and 4 cables each with three wires line, neutral and earth.

Since you have a cable with just red and earth clearly the normal standard has not been used, BAS is correct, no one should try and guess what you have. The only option is to test the cables.

 

[securespark]

Using singles was "normal" in at least the 60's, 70's and 80's. I have seen many installs done this way.

But it doesn't help me to diagnose how they connect together.
The twin red looks like a switch wire (but if the spark ran out of red/ black, it could be line/ neutral) , the single red could be anything (live loop (L or N) or switched line, and the brown/ blue is either a newer addition or is flex.

As people say, you need a multimeter to find out what is what.

Looking in the switch may help.

 

[JohnW2]

Using singles was "normal" in at least the 60's, 70's and 80's. I have seen many installs done this way.

... but what about 'single and earth' such as the OP described - how common was that (I've personally never seen/handled the stuff, although I know it exists)?

I suppose it's possible that what he's got is actually T+E with the black core cut back and not visible.

As for the rest, we can all speculate in all sorts of ways, but, as has been said, only someone on site will be able to work out what the cables/conductors all are.

Kind Regards, John

 

[ban-all-sheds]

TBF, John, secure has probably fiddled around in many orders of magnitude more different properties than you.

 

[JohnW2]

Hence my question

 

[securespark]

Single and earth too, yes. I helped on a rewire in 1982 when it was used and have seen it on younger installs, although by around the mid-late 80's, it was dying out.