Wall Lights in New House - Wiring question/problem
Wall Lights in New House - Wiring question/problem
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Discussion

TedMaul

Original Poster:

2,092 posts

244 months

Tuesday 19th August 2008
quotequote all
Moved into a new house last week, previous owners took all three wall lights. Not sure why, but hey-ho. Anyway, Mrs Maul chose some new ones and I set about connecting them up - previous owner just left connector blocks sticking out of wall with wires connected in.

Fitted first light and tested it which worked fine, fitted second which worked fine. When I went to fit the third light, I noticed that the old connector block had two live wires twisted together and two neutrals twisted together and both connected in to the block. There were also two earths twisted together, neither of which were connected into the old block.

I connected the third light up, including the earth and all three wall lights worked fine....but..... all of the upstairs lights stopped working??? None of the breakers refused to go back on, master didn't trip, nothing else at all. Disconnected third light and all upstairs lights work again. Last night, all the bulbs in the remaining two new fitting blew at once when I switched them on???

Previous owner says 2nd circuit on light fitting is to do with the wiring for an alarm, but he didnt understand as he always pays for an electrician to do everything?

Any idea why one light would have two lives, neutrals and earths and why it would stop the upstairs circuit working (I assume they are linked in some way, but no idea why or what to do about it)

Ta

Ted

PS I did flick the breakers each time I fitted/tested a light!

williamp

20,456 posts

304 months

Tuesday 19th August 2008
quotequote all
TedMaul said:
Moved into a new house last week, previous owners took all three wall lights. Not sure why, but hey-ho. Anyway, Mrs Maul chose some new ones and I set about connecting them up - previous owner just left connector blocks sticking out of wall with wires connected in.

Fitted first light and tested it which worked fine, fitted second which worked fine. When I went to fit the third light, I noticed that the old connector block had two live wires twisted together and two neutrals twisted together and both connected in to the block. There were also two earths twisted together, neither of which were connected into the old block.

I connected the third light up, including the earth and all three wall lights worked fine....but..... all of the upstairs lights stopped working??? None of the breakers refused to go back on, master didn't trip, nothing else at all. Disconnected third light and all upstairs lights work again. Last night, all the bulbs in the remaining two new fitting blew at once when I switched them on???

Previous owner says 2nd circuit on light fitting is to do with the wiring for an alarm, but he didnt understand as he always pays for an electrician to do everything?

Any idea why one light would have two lives, neutrals and earths and why it would stop the upstairs circuit working (I assume they are linked in some way, but no idea why or what to do about it)

Ta

Ted

PS I did flick the breakers each time I fitted/tested a light!
#

Its not unknown for people to use colourd wire for other uses- so the earth might not be an earth, eve though it is coulured like an earth. If the other two lights you fitted just needed two wires, these are what I would use. If they had three, then I would use a multimeter and measure the resistance on the wires between light 2 and 3. What i'm getting at is one of those wires you connected up is sending power straight to earth, so no upstairs light gets power. If you dont connect it up, and protect it with insulating tape, you'll be fine.

TedMaul

Original Poster:

2,092 posts

244 months

Tuesday 19th August 2008
quotequote all
williamp said:
TedMaul said:
Moved into a new house last week, previous owners took all three wall lights. Not sure why, but hey-ho. Anyway, Mrs Maul chose some new ones and I set about connecting them up - previous owner just left connector blocks sticking out of wall with wires connected in.

Fitted first light and tested it which worked fine, fitted second which worked fine. When I went to fit the third light, I noticed that the old connector block had two live wires twisted together and two neutrals twisted together and both connected in to the block. There were also two earths twisted together, neither of which were connected into the old block.

I connected the third light up, including the earth and all three wall lights worked fine....but..... all of the upstairs lights stopped working??? None of the breakers refused to go back on, master didn't trip, nothing else at all. Disconnected third light and all upstairs lights work again. Last night, all the bulbs in the remaining two new fitting blew at once when I switched them on???

Previous owner says 2nd circuit on light fitting is to do with the wiring for an alarm, but he didnt understand as he always pays for an electrician to do everything?

Any idea why one light would have two lives, neutrals and earths and why it would stop the upstairs circuit working (I assume they are linked in some way, but no idea why or what to do about it)

Ta

Ted

PS I did flick the breakers each time I fitted/tested a light!
#

Its not unknown for people to use colourd wire for other uses- so the earth might not be an earth, eve though it is coulured like an earth. If the other two lights you fitted just needed two wires, these are what I would use. If they had three, then I would use a multimeter and measure the resistance on the wires between light 2 and 3. What i'm getting at is one of those wires you connected up is sending power straight to earth, so no upstairs light gets power. If you dont connect it up, and protect it with insulating tape, you'll be fine.
Other two lights did have three wires each and I'm reluctant to leave the third one with no earth. Its a very odd setup indeed.

Brite spark

2,106 posts

232 months

Tuesday 19th August 2008
quotequote all
The red and black (or brown and blue) may not be the conductor that you expect them to be, when working with "twin and earth" lighting but not the earth


DO NOT CONNECT THE EARTH IN SUBSTITUTE FOR ONE OF THE OTHER WIRES UNDER ANY CIRCUMSTANCE, IT'S NOT CALLED THE CIRCUIT PROTECTIVE CONDUCTOR FOR FUN!!

It is possible that one of the wires you are thinking of as a live is in fact the neutral,
however that is assuming that the lighting circuit worked properly before the old lights were removed,
that you have not bought a dodgy fitting
and that the wiring in the connector blocks is the only wiring to of been touched.

Unless you are confident with this (which I assume you are not) get an electrician. If the fittings should of been included in the sale of the house then contact your solicitor to see if the vendor should pay for the cost of electrician/fittings- usually a thread running in sp&l about similar things- one currently about a house with no tv ariel.


Simpo Two

93,036 posts

296 months

Tuesday 19th August 2008
quotequote all
Invest £2 on an elctrical screwdriver (ie has a neon fitted). When it touches a live wire, it lights up orange - which is infinitely better than YOU lighting up orange! £2 could save your life.

AndrewTait

1,849 posts

225 months

Tuesday 19th August 2008
quotequote all
Brite spark said:
If the fittings should of been included in the sale of the house then contact your solicitor to see if the vendor should pay for the cost of electrician/fittings- usually a thread running in sp&l about similar things- one currently about a house with no tv ariel.
What? They were supposed to leave the washing powder behind? smile

Brite spark

2,106 posts

232 months

Tuesday 19th August 2008
quotequote all
Simpo Two said:
Invest £2 on an elctrical screwdriver (ie has a neon fitted). When it touches a live wire, it lights up orange - which is infinitely better than YOU lighting up orange! £2 could save your life.
he's working on a dead circuit so it won't help- I'm not going to suggest working live to him- dangerous and won't really help find the fault unless he knows hat he is doing.

neon screwdrivers do not always light up, so can not be trusted as a definitive guide to wether the wire is dead

Ganglandboss

8,561 posts

234 months

Tuesday 19th August 2008
quotequote all
Brite spark said:
neon screwdrivers do not always light up, so can not be trusted as a definitive guide to wether the wire is dead
yes I'd trust a neon driver to tell me if something is dead about as much as I'd trust Michael Jackson to babysit.


Ganglandboss

8,561 posts

234 months

Tuesday 19th August 2008
quotequote all
The best thing to do here is get a proper spark in. I am a qualified spark and there's no way stuff like this can be diagnosed on an internet forum. Your best bet is to get someone in who knows what they're doing and get them to have a good look around while they're at it.

MonkeyHanger

9,267 posts

273 months

Tuesday 19th August 2008
quotequote all
Ganglandboss said:
The best thing to do here is get a proper spark in. I am a qualified spark and there's no way stuff like this can be diagnosed on an internet forum. Your best bet is to get someone in who knows what they're doing and get them to have a good look around while they're at it.
Far too sensible for PH i'm afraid. What you really need is a bunch I.T types or other desk jockeys to post about how they'd do it.


As for a £2 neon driver saving your life (other post), it could just as easily kill you. They're st.

TedMaul

Original Poster:

2,092 posts

244 months

Thursday 21st August 2008
quotequote all
Thx for all the advice. Fittings were not included, they wanted to take them and a whole load of other things (such as blinds, curtains etc).

Resigned myself to getting a sparky in so will ask neighbours if they use anyone trustworthy as I don;t want the previous owners sparky in, as its likely he did the bodge in the first place!

monthefish

20,467 posts

262 months

Thursday 21st August 2008
quotequote all
williamp said:
Its not unknown for people to use colourd wire for other uses-
yes

I was replacing a light fitting once, spent over an hour trying to work out the wiring (I'm usually pretty good at these things), so eventaully gave up and called in a spark and he told me that most of the wires were the wrong colour, and it looked like the previous installer had just used whatever wire was close to hand at the time.yikes

pdV6

16,442 posts

292 months

Thursday 21st August 2008
quotequote all
TedMaul said:
Thx for all the advice. Fittings were not included, they wanted to take them and a whole load of other things (such as blinds, curtains etc).
Actually, when light fittings are not included in a sale, it is usual practice for the contract to specify that a bog standard lamp be fitted by the vendor to replace the fancy one they're taking. Leaving wires hanging out of the wall is not acceptable.

Check with your solicitor / conveyancer to see what was specified.

Simpo Two

93,036 posts

296 months

Thursday 21st August 2008
quotequote all
Brite spark said:
neon screwdrivers do not always light up, so can not be trusted as a definitive guide to wether the wire is dead
Depends how smart you are. I test mine on the wire live first to make sure it works. Then I turn the power off and try again. Things on the same circuit that all go off when I throw the trip is also handy evidence.

There is more chance that the neon will work than that it will have failed at exactly the same time. Therefore I maintain that it *could* save your life.

So, experts - you have a wire sticking out of a wall that may or may not be live. How do YOU find out?


Edited by Simpo Two on Thursday 21st August 14:09

Ganglandboss

8,561 posts

234 months

Thursday 21st August 2008
quotequote all
Simpo Two said:
Brite spark said:
neon screwdrivers do not always light up, so can not be trusted as a definitive guide to wether the wire is dead
Depends how smart you are. I test mine on the wire live first to make sure it works. Then I turn the power off and try again. Things on the same circuit that all go off when I throw the trip is also handy evidence.

There is more chance that the neon will work than that it will have failed at exactly the same time. Therefore I maintain that it *could* save your life.

So, experts - you have a wire sticking out of a wall that may or may not be live. How do YOU find out?


Edited by Simpo Two on Thursday 21st August 14:09
With a set of GS38 approved test lamps with two test probes. The neon screwdriver uses your body as an earth reference - that is nowhere near as reliable as a proper earth connection.

anonymous-user

85 months

Thursday 21st August 2008
quotequote all
Simpo Two said:
Brite spark said:
neon screwdrivers do not always light up, so can not be trusted as a definitive guide to wether the wire is dead
Depends how smart you are. I test mine on the wire live first to make sure it works. Then I turn the power off and try again. Things on the same circuit that all go off when I throw the trip is also handy evidence.

There is more chance that the neon will work than that it will have failed at exactly the same time. Therefore I maintain that it *could* save your life.

So, experts - you have a wire sticking out of a wall that may or may not be live. How do YOU find out?


Edited by Simpo Two on Thursday 21st August 14:09
With a multi meter rolleyes & if you haven't got one of them then you shouldn't be touching anything.