Hi,

I was about to replace a what I imagined was a simple light fitting (done it
many times before) obviously expected L N E wiring, instead on undoing the
old fitting I found a total of 3 cables each with a red and black (live and
neutral?)

all three red wires go into a connection on the old light fitting, 2 black
cables go into a connection and a single black cable goes into a connection.

Unfortunately the fitting does not mark LNE so I find myself completely
lost. I obviously assume that red is live but unsure of what is neutral and
what is earth. Is this a standard arrangement (it is wiring from a 1980's
extension) and can anyone give me an explanation of what to do now and how
to identify the cables!

Many Thanks

Chris
Essex

On Tue, 8 Mar 2005 20:28:06 UTC, "news"
wrote:

I was about to replace a what I imagined was a simple light fitting (done it
many times before) obviously expected L N E wiring, instead on undoing the
old fitting I found a total of 3 cables each with a red and black (live and
neutral?)

This is a very common (and normal) situation.

What you have is a power feed coming (ultimately) from the consumer
unit. One of the cables will be this (line and neutral from consumer
unit). The power feed then continues to the next ceiling rose, the next,
and so on, until the whole of the lighting circuit is finished. The last
rose will thus have only two cables. This is obviously not the last one!

So, the third cable goes to the switch. Beware - both wires (red and
black) are really live, but the black one will be live only when the
switch is on. So the third red will be line to the switch, and the third
black will be line back from the switch, to the actual bulb. Technically
the ends of this black should be sleeved or whatever in a red colour.

all three red wires go into a connection on the old light fitting

One in, one out, one to the switch. All line.

2 black
cables go into a connection

That is to (a) connect the incoming feed to the outgoing (to next
fitting) feed, neutral. It also provides neutral, via that terminal, to
the bulb itself.

and a single black cable goes into a connection.

That's the return cable from the switch and will be live when the switch
is on.

In addition, all the earth wires should be bare (but sleeved
green/yellow) and connected together. This terminal also gives an
opportunity to earth the fitting, if it requires it.

Is this a standard arrangement

Very standard.

You can deduce which is the switch cable, from the above. It doesn't
actually matter about the other two; no need to differentiate them.

Now you know what they all do, you should hopefully understand how to
replace it. If not, get a sparky in!

NOTE 1: This all assumes it's correctly wired.
NOTE 2: For 'bulb' read 'whatever the light emitting device actually is'

--
Bob Eager
begin a new life...dump Windows!

On Tue, 08 Mar 2005 20:28:06 GMT, "news"
wrote:

Hi,

I was about to replace a what I imagined was a simple light fitting (done it
many times before) obviously expected L N E wiring,

Why did you "obviously" expect this?

That said, it's what you've got.

instead on undoing the
old fitting I found a total of 3 cables each with a red and black (live and
neutral?)

That's more normal, yes.

It is called three plate wiring, and is by far the most common type of
wiring in UK lighting circuits.

all three red wires go into a connection on the old light fitting, 2 black
cables go into a connection and a single black cable goes into a connection.

Yep. There'd probably be a bang if they didn't.

That'd be Live feed IN, Live feed OUT, and Switched Live.

The two black wires are Neutral Feed IN and Neutral feed OUT.

The single black wire is Switched LIVE and should be sheathed RED at
both the fitting AND the switch.

Unfortunately the fitting does not mark LNE so I find myself completely
lost.

Standard ceiling roses generally don't.

But then, they weren't designed with people with no idea of the work
involved in mind. They were designed to be fitted by electricians.

I obviously assume that red is live but

have lived to tell the tale.

One simple rule where electricity is concerned -

- never assume. It is idiotic in the extreme.

You'll be telling us next that all black wires are neutral, by
assumption. By that reckoning, you just got a belt off the fitting,
since you also assumed it was switched off, and was, in fact, not, and
felt it safe to play with all the black wires you mentioned.

You see why electricians go to college to learn about these things?

unsure of what is neutral and
what is earth.

Earth would be all the (no doubt) missing or bare wires connected to
the big terminal opposite the three plate arrangement you described
above. There should be three wires.

Is this a standard arrangement (it is wiring from a 1980's
extension)

Yes.

and can anyone give me an explanation of what to do now and how
to identify the cables!


See above, and at the least, buy a book on electricity.

news wrote:
Hi,

I was about to replace a what I imagined was a simple light fitting
(done it many times before) obviously expected L N E wiring, instead
on undoing the old fitting I found a total of 3 cables each with a
red and black (live and neutral?)

all three red wires go into a connection on the old light fitting, 2
black cables go into a connection and a single black cable goes into
a connection.


http://www.userview.net/loop1.html

Si

news wrote:
Hi,

I was about to replace a what I imagined was a simple light fitting (done it
many times before) obviously expected L N E wiring, instead on undoing the
old fitting I found a total of 3 cables each with a red and black (live and
neutral?)

all three red wires go into a connection on the old light fitting, 2 black
cables go into a connection and a single black cable goes into a connection.

Unfortunately the fitting does not mark LNE so I find myself completely
lost. I obviously assume that red is live but unsure of what is neutral and
what is earth. Is this a standard arrangement (it is wiring from a 1980's
extension) and can anyone give me an explanation of what to do now and how
to identify the cables!

Many Thanks

Chris
Essex


As others have said, this is standard in modern UK houses for at least
30 years. Its a very common mistake for a newbie to remove all the wires
from the fitting and then expect someone else to sort it out remotely. :-)
Keeps happening to me with my relatives.

see http://www.diydoctor.org.uk/projects...ghtfitting.htm

Thanks for your advice I will get in a electrician rather than kill myself,
child, wife, etc (yes in that order). As despite the rather details
explanations offered so graciously I still can't translate it into simple L
N E on my simple wickes fitting! It is interesting to note that despite the
fact that this arrangement is normal, fitments still come with overly
simplfied instructions. Why can't the wires that decend from my ceiling
match the f***ing diagram!

As a end note I know that as a complete amateur/dangerous electrician I
sound completely thick but honestly if you ever need life
support/haemodialysis/intropes I am your man!

Best Wishes

Chris



"news" wrote in message
k...
Hi,

I was about to replace a what I imagined was a simple light fitting (done
it many times before) obviously expected L N E wiring, instead on undoing
the old fitting I found a total of 3 cables each with a red and black
(live and neutral?)

all three red wires go into a connection on the old light fitting, 2 black
cables go into a connection and a single black cable goes into a
connection.

Unfortunately the fitting does not mark LNE so I find myself completely
lost. I obviously assume that red is live but unsure of what is neutral
and what is earth. Is this a standard arrangement (it is wiring from a
1980's extension) and can anyone give me an explanation of what to do now
and how to identify the cables!

Many Thanks

Chris
Essex

Dear Sugar Free

Your post made the most sense to me so I wondered if you could offer further
info... Firstly all your comment are correct regarding stupidity etc.
However having some previous disasters I am now extremely careful when it
comes to 240v! Therefore looked at the instructions that came with the light
fitting (yes it only talks about three cables LNE! it is a stupid assumption
that Wickes would bother to full inform me about real wiring).

You mentioned that the cables came in three groups to three connections for
a reason.

First group 3 all red and all live (Live feed IN, Live feed OUT, and
Switched Live)

Second Group 2 all black and neutral (Neutral Feed IN and Neutral feed OUT)

Third Group 1 cable black and live (Switched LIVE) this should really be
sheathed with red

How do I relate this to my L N E connections on my light fitting?

Many Thanks

Chris
Essex (obviously)











"Sugar Free" wrote in message
...
On Tue, 08 Mar 2005 20:28:06 GMT, "news"
wrote:

Hi,

I was about to replace a what I imagined was a simple light fitting (done
it
many times before) obviously expected L N E wiring,

Why did you "obviously" expect this?

That said, it's what you've got.

instead on undoing the
old fitting I found a total of 3 cables each with a red and black (live
and
neutral?)

That's more normal, yes.

It is called three plate wiring, and is by far the most common type of
wiring in UK lighting circuits.

all three red wires go into a connection on the old light fitting, 2 black
cables go into a connection and a single black cable goes into a
connection.

Yep. There'd probably be a bang if they didn't.

That'd be Live feed IN, Live feed OUT, and Switched Live.

The two black wires are Neutral Feed IN and Neutral feed OUT.

The single black wire is Switched LIVE and should be sheathed RED at
both the fitting AND the switch.

Unfortunately the fitting does not mark LNE so I find myself completely
lost.

Standard ceiling roses generally don't.

But then, they weren't designed with people with no idea of the work
involved in mind. They were designed to be fitted by electricians.

I obviously assume that red is live but

have lived to tell the tale.

One simple rule where electricity is concerned -

- never assume. It is idiotic in the extreme.

You'll be telling us next that all black wires are neutral, by
assumption. By that reckoning, you just got a belt off the fitting,
since you also assumed it was switched off, and was, in fact, not, and
felt it safe to play with all the black wires you mentioned.

You see why electricians go to college to learn about these things?

unsure of what is neutral and
what is earth.

Earth would be all the (no doubt) missing or bare wires connected to
the big terminal opposite the three plate arrangement you described
above. There should be three wires.

Is this a standard arrangement (it is wiring from a 1980's
extension)

Yes.

and can anyone give me an explanation of what to do now and how
to identify the cables!


See above, and at the least, buy a book on electricity.

news wrote:

Dear Sugar Free

Your post made the most sense to me so I wondered if you could offer further
info... Firstly all your comment are correct regarding stupidity etc.
However having some previous disasters I am now extremely careful when it
comes to 240v! Therefore looked at the instructions that came with the light
fitting (yes it only talks about three cables LNE! it is a stupid assumption
that Wickes would bother to full inform me about real wiring).

You mentioned that the cables came in three groups to three connections for
a reason.

First group 3 all red and all live (Live feed IN, Live feed OUT, and
Switched Live)

Ignore this group.
It is not needed for your light fitting.
You will find a live else where. See below.

Second Group 2 all black and neutral (Neutral Feed IN and Neutral feed OUT)

This is the neutral you need to feed to your new light fitting.

Third Group 1 cable black and live (Switched LIVE) this should really be
sheathed with red

????

Are you saying that as a group you have a live and a black, or are you
saying that you have a single core that is black and that it is a
switched live?
If the latter, then this is your live (switched) to your new light fitting.
Connect this to the live on your new light fitting, but before you do,
stick a bit of red tape on it.

How do I relate this to my L N E connections on my light fitting?

To sum up....
Light fitting live is connected to the single black that should have a
red sleeve on it.
Light fitting neutral is wired to the 3 black cables.
Earth is connected to the, presumably green and yellow sheathed cables
that you have.


HTH

Dave

Many Thanks

Chris
Essex (obviously)
^^^^^^^

Why?

Do you wear white high heels and have blonde hair ;-)

On Tue, 8 Mar 2005 22:37:00 UTC, Dave wrote:

Chris
Essex (obviously)
^^^^^^^

Why?

Do you wear white high heels and have blonde hair ;-)

pedant
Hair coloured blonde...
/pedant

--
Bob Eager
begin a new life...dump Windows!

Bob Eager wrote:
On Tue, 8 Mar 2005 22:37:00 UTC, Dave wrote:


Chris
Essex (obviously)

^^^^^^^

Why?

Do you wear white high heels and have blonde hair ;-)


pedant
Hair coloured blonde...
/pedant

Sorry, I forgot ;-)

Dave

news wrote:
Thanks for your advice I will get in a electrician rather than kill myself,
child, wife, etc (yes in that order). As despite the rather details
explanations offered so graciously I still can't translate it into simple L
N E on my simple wickes fitting! It is interesting to note that despite the
fact that this arrangement is normal, fitments still come with overly
simplfied instructions. Why can't the wires that decend from my ceiling
match the f***ing diagram!

By way of explanation, the trouble is there are different ways of wiring
lights; the first way is what you've got, using ceiling roses which have
two or three stiff cables entering and leaving, plus usually a thin flex
leading down to the actual bulb fitting.

The second way is using junction boxes, invisible *above* the ceiling...
in this case, the same two or three cables enter the junction box, and
instead of the thin flex leading to the bulb, you have another stiff
cable leaving the junction box, and passing down through the ceiling
(and which will also connect, indirectly, to the bulb). That is what
you can see in the instructions. Electrically speaking, the connections
inside the ceiling rose are just the same as in the junction box; and
for almost any light fittings you buy in a shop, a junction-box wiring
system is what you need. I think you're right to get an electrician in
to sort it.

David

In article ,
news wrote:
How do I relate this to my L N E connections on my light fitting

Best thing to do is to buy a 3 plate ceiling rose - about 1.50 squids -
and examine it. Far better than any explanation. And if this doesn't help
you understand how they are wired, get a pro in. :-)

--
*Plagiarism saves time *

Dave Plowman London SW
To e-mail, change noise into sound.

news wrote:
Thanks for your advice I will get in a electrician rather than kill myself,
child, wife, etc (yes in that order). As despite the rather details
explanations offered so graciously I still can't translate it into simple L
N E on my simple wickes fitting! It is interesting to note that despite the
fact that this arrangement is normal, fitments still come with overly
simplfied instructions. Why can't the wires that decend from my ceiling
match the f***ing diagram!

As others have said - because there are different ways of wiring
lighting circuits, all of which are legitimate and safe, it's hard to
create comprehensive instructions which deal with all the common(ish)
cases. It's also cheaper to manufacture 'universal' light-fittings which
just accept the basic L,N,E needed to make them work, than to create
national variants which integrate smoothly into the 'typical' ways
lighting circuits are arranged in different countries.

There is, though, a way to keep things simple: but at the expense of it
looking naff. How much the naffness matters is for you to decide. Leave
in place the existing ceiling 'rose' - the thing with the three
terminals you've mentioned (and the fourth one, where all the earth
wires we hope you have meet up, which you haven't mentioned). Choose a
new spot on the ceiling, close by, for your new fitting, and attach it -
direct to the ceiling or to a new ceiling rose, depending on what it
expects. Now run a short piece of 3-core flex from that fitting to the
old rose. At the new fitting, connect the 3 cores to the 'obvious'
terminals - brown to L, blue to N, green/yellow to E. In the old ceiling
rose we're leaving in place - and haven't disconnected any of the fixed
wiring from - connect (a) the green/yellow to the earth terminal, where
all the sleeved-but-naturally-bare earth conductors are squished in; (b)
the blue to the outer terminal where the two black conductors go (and
where the blue wire of the old hanging lampholder flex was - and maybe
still is connected); (c) the brown to the other outer terminal where the
single black conductor is connected (and where the brown wire of the old
lampholder flex was).

If that's either too nafflooking, or in the slightest bit unclear, stick
to saving lives and track down a sparks willing to do a small quick job
in Essex (good luck ;-)! If the naffness is marginal, you could do it
'for now' and get the sparks in once you've a couple more small
electrickle jobs need doing, and get them to tidy this up as part of the
slightly larger job (which it might be easier to get someone interested in).

HTH - Stefek

In message , news
writes
Thanks for your advice I will get in a electrician rather than kill myself,
child, wife, etc (yes in that order).

Fair enough, though it's unlikely you'd kill anyone directly, though you
may trip an MCB/blow a fuse.

As despite the rather details
explanations offered so graciously I still can't translate it into simple L
N E on my simple wickes fitting!

The 'problem' you have come across is common with light fittings rather
than just a ceiling rose. I do think it is a bit unhelpful to produce
fittings without the necessary terminals for loop-in wiring, given that
it is the standard way to wire lights in the UK. Let alone supply
instructions which as you have found aren't going to be helpful, and
possibly dangerous (presumably because they are sold in various
countries)

What I do is either convert to a junction box in the ceiling space, or
use some choc block connectors to take the connections that would go
into the various terminals on a the ceiling rose, then connect the
switched live connections to the 'live' and 'neutral' terminals on the
fitting. If it has an Earth connection (if is metal it should), then
connect that to earth.
--
Chris French, Leeds

Earth is connected to the, presumably green and yellow sheathed cables
that you have.

If there are no green/yellow sheathed conductors, then the circuit has no
earth available. If the light fitting has an earth connection (usually
because it has exposed metal parts), then you can't fit it and should return
it to the shop.

Christian.

On Tue, 08 Mar 2005 22:08:06 GMT, "news"
wrote:

Dear Sugar Free

They call me that for a reason :-) Must be the "niceness" all taken
out.

Your post made the most sense to me so I wondered if you could offer further
info... Firstly all your comment are correct regarding stupidity etc.

Those comments are for your safety - not my ego.

When you've done a job like this twenty years and more, you've seen
enough in the way of "DIY" electrical work that comes close to "DIY"
funeral services.

I've nothing at all against anyone having a go, only so long as they
bother to understand what they're doing first.

Patronising

You did the right thing in asking, rather than attempting without
knowlege....

/patronising

You mentioned that the cables came in three groups to three connections for
a reason.

Yep - the wires do different things. If you put 'em all together,
you'd get a bang, and probably, a shock.

First group 3 all red and all live (Live feed IN, Live feed OUT, and
Switched Live)

Yes, the LIVE side of the switch - that is, the voltage going to the
switch, returning to the fitting when the switch is ON.

Second Group 2 all black and neutral (Neutral Feed IN and Neutral feed OUT)

Yep.

Third Group 1 cable black and live (Switched LIVE) this should really be
sheathed with red

Absolutely should be.

How do I relate this to my L N E connections on my light fitting?

The three red wires (L-IN, L-OUT, L-SW) can go into a connector
together, and effectively removed from your equation. A small
junction box which you can "hide" back up in the ceiling would help
here.

The TWO black wires - your neutrals - got to N on your fitting -
again, put them into the little juntion box and run out a tail to
connect into your fitting.

The SINGLE wire, which should be red, but is black, and should be
sheathed red, but isn't, is the return from the switch. When the
switch is turned on, this provides the feed to your fitting, and so it
goes to L on your fitting. Again, put this into your junction box,
sheath it, and run out a red tail into your fitting.

Many Thanks

Chris
Essex (obviously)

Sugar Free,

Understand now, thanks a lot mate!

Chris
Blonde
Essex

"Sugar Free" wrote in message
...
On Tue, 08 Mar 2005 22:08:06 GMT, "news"
wrote:

Dear Sugar Free

They call me that for a reason :-) Must be the "niceness" all taken
out.

Your post made the most sense to me so I wondered if you could offer
further
info... Firstly all your comment are correct regarding stupidity etc.

Those comments are for your safety - not my ego.

When you've done a job like this twenty years and more, you've seen
enough in the way of "DIY" electrical work that comes close to "DIY"
funeral services.

I've nothing at all against anyone having a go, only so long as they
bother to understand what they're doing first.

Patronising

You did the right thing in asking, rather than attempting without
knowlege....

/patronising

You mentioned that the cables came in three groups to three connections
for
a reason.

Yep - the wires do different things. If you put 'em all together,
you'd get a bang, and probably, a shock.

First group 3 all red and all live (Live feed IN, Live feed OUT, and
Switched Live)

Yes, the LIVE side of the switch - that is, the voltage going to the
switch, returning to the fitting when the switch is ON.

Second Group 2 all black and neutral (Neutral Feed IN and Neutral feed
OUT)

Yep.

Third Group 1 cable black and live (Switched LIVE) this should really be
sheathed with red

Absolutely should be.

How do I relate this to my L N E connections on my light fitting?

The three red wires (L-IN, L-OUT, L-SW) can go into a connector
together, and effectively removed from your equation. A small
junction box which you can "hide" back up in the ceiling would help
here.

The TWO black wires - your neutrals - got to N on your fitting -
again, put them into the little juntion box and run out a tail to
connect into your fitting.

The SINGLE wire, which should be red, but is black, and should be
sheathed red, but isn't, is the return from the switch. When the
switch is turned on, this provides the feed to your fitting, and so it
goes to L on your fitting. Again, put this into your junction box,
sheath it, and run out a red tail into your fitting.

Many Thanks

Chris
Essex (obviously)

In message , news
writes
Sugar Free,

Understand now, thanks a lot mate!

Chris
Blonde
Essex

Dear essex blonde - please don't top post

--
geoff