My shocking lack of knowledge! Ask questions and find answers to many subjects relating to electrics and electrical work

[tonyade]

Hello guys.

Just trying to update a old light fitting. The only thing is, there are two red wires and one black. Any idea what I connect the extra red wire to? Or does it just need to be insulated?

You see, my lack of electrical knowledge is really shocking.

Thanks for any replies (even the abusive ones...)

[kbrownie]

tonyade,
Need a bit more detail!
Firstly, are you sure there is not another black stuck up in ceiling.
Have a look at cables in switch and identify colours and do you know the difference between singles and twin core if so, what are your's and is there and earth cable(could be yellow/green, green or bare copper)?
KB

[TOPSPARK]

Tony you have not said wether there is an earth wire to this old light fitting you are changing and there should be 3 reds and a black .what you could have is single wires and 1 has broken and gone back up in the ceiling but with so little knowledge to go on i would hesitate to advise you
but if you could give more info i will galdly try and help
regards
Topspark

[tonyade]

Hello chaps. Looks like there are three red wires and one black.

[url]http://www.flickr.com/photos/29332773@N06/2738583530[/url]

Thanks.

[ericmark]

I would think you will find more wires as you enlarge the hole. Unless end of line and I see no earth cables? May be very old as years ago we did not use earth on lights. I have tried to enhance photo to see into hole but can't see anything. I know with my own house I had to remove the plaster then make good to get at the cables. If no earth then you are limited to non metallic lamps until you re-wire. What is at the switch are there any earths? And what colours I think maybe two reds? In which case seems you have wired correct just need a connection block on twisted cables.
Eric

[tonyade]

Hi Eric. Thanks for taking the time out to respond to my post. It's a 50s property, so they're probably the original connections. And you're right, I think it could be the end of the line. It's in the last bedroom upstairs. (I'll check the other connections in the other rooms just to make sure). Last question: if I put a block on it, it's it OK to tuck it up in the hole? Or should I just leave it hanging down, hidden by the plastic covering?

Cheers again.

FYI: there are no more wires. Just three reds (two tied together) and one black. Haven't taken the switch off, but it looks fairly new.

[ericmark]

What is common and what one should are different. And it is common to shove cables up the hole. The problem arises if someone then removes a floor board and accesses them from above to touches a live cable. But I am sure now you know they are there you will not do anything silly. Do consider lack of earth and take precautions like no metal fitting and consider getting checked to ensure there are no further problems. If rubber cable may need a re-wire and if not with no earths you may consider a part re-wire when funds allow.
All best Eric

[tonyade]

Hello again, chaps. Well, I messed that one up.

Stuck the two red wires into a terminal connector, then wrapped it in some red insulating tape. Then wired black to blue, and red to brown. Then I slipped the plastic fitting over the wires, with the two insulated red wires hanging inside this - not touching any metal. I then put the power back on and clicked the switch. Nothing happened. Then I tried to touch the bulb and there was a slight bang and the bulb (energy-saver) cracked.

Now a couple of sockets in the next room aren't working. Any ideas what can be wrong?

Thanks in advance.

[ericmark]

I would say time to get someone in. To continue is far too dangerous as something to which we are unaware is going on. Seem to remember I did query the type of wiring and age before.
May be just disturbing old cables is causing the problem and only being on site can really these faults be seen.
Eric

[tonyade]

Yeah, you're right. Thanks for all the useful advice though. I'm sure I'll be back!

Cheers