"Matthew Durkin" wrote in message
...
My Sister has just bought an old house pre-20th century house. We've found
a
couple of mains cables running from the fusebox that have a lead sheath
(they looked just like the modern plastic ones until I scratched the paint
off and they revealed shiny lead.
Not sure yet where they run, but my hunch is the lighting circuits.
Getting them out will be very difficult (especially for my sister!)
What current would these be normally rated at?
Could they be dangerous - how can I tell?
Is there any way of safety testing them?
Any other comments?
Thanks,
Matthew



If they are still live, turn the mains off at the fuse box and the
instalation is not to be turned back on untill inspected by a qualified
electrician.....

Lead went out with the ark, is is the rubber at the ends that degrades.

Matthew Durkin wrote:
My Sister has just bought an old house pre-20th century house. We've found a
couple of mains cables running from the fusebox that have a lead sheath
(they looked just like the modern plastic ones until I scratched the paint
off and they revealed shiny lead.
Not sure yet where they run, but my hunch is the lighting circuits.
Getting them out will be very difficult (especially for my sister!)
What current would these be normally rated at?
Could they be dangerous - how can I tell?
Is there any way of safety testing them?


My biggest concern would be for the insulation within the cable - it
can't be in very good condition after all that time. I would replace the
cable runs. It is rarely as difficult as it looks, and anyone who is
competent at wiring should have no trouble doing so.

--
Grunff

My Sister has just bought an old house pre-20th century house. We've found a
couple of mains cables running from the fusebox that have a lead sheath
(they looked just like the modern plastic ones until I scratched the paint
off and they revealed shiny lead.
Not sure yet where they run, but my hunch is the lighting circuits.
Getting them out will be very difficult (especially for my sister!)
What current would these be normally rated at?
Could they be dangerous - how can I tell?
Is there any way of safety testing them?
Any other comments?
Thanks,
Matthew

In message , James
Salisbury writes

"Matthew Durkin" wrote in message
...
My Sister has just bought an old house pre-20th century house. We've found
a
couple of mains cables running from the fusebox that have a lead sheath
(they looked just like the modern plastic ones until I scratched the paint
off and they revealed shiny lead.
Not sure yet where they run, but my hunch is the lighting circuits.
Getting them out will be very difficult (especially for my sister!)
What current would these be normally rated at?
Could they be dangerous - how can I tell?
Is there any way of safety testing them?
Any other comments?


If they are still live, turn the mains off at the fuse box and the
instalation is not to be turned back on untill inspected by a qualified
electrician.....

Lead went out with the ark, is is the rubber at the ends that degrades.


Well, yes that is the 'correct' thing to do probably.

However, turning off the mains fore the whole house may not be very
practicable.

Yes, it would be worried about the insulation inside this cable which is
likely to be rubber - or rather I'd be worried about the insulation at
the ends of the cable where it terminates.


But my experience of a house that had a fir bit of original 1930's
rubber insulated cable (and I had a bit of this lead sheathed cable as
well) is that it's mostly ok until you start fiddling with it, when of
course the insulation drops off and then becomes rather dangerous.

To the OP, yes I'd assume this is unsafe and leave it alone and I'd want
to replace it ASAP, either myself or getting an electrician in. I'd also
want to check the rest of the installation. And don't be taken in by
first appearances. Our house had had a lot of work done in the 60's
sockets and new light circuits had been wired in PVC cable, but the new
light switches had just been connected to the old rubber 1930's wiring.
--
Chris French, Leeds

In article ,
Matthew Durkin wrote:
My Sister has just bought an old house pre-20th century house. We've
found a couple of mains cables running from the fusebox that have a
lead sheath (they looked just like the modern plastic ones until I
scratched the paint off and they revealed shiny lead. Not sure yet
where they run, but my hunch is the lighting circuits. Getting them out
will be very difficult (especially for my sister!) What current would
these be normally rated at? Could they be dangerous - how can I tell? Is
there any way of safety testing them? Any other comments?

Most of the lighting wiring in my house was lead when I bought it, and it
was old then - about 30 years ago.

However, I was surprised to find that only the rubber insulation exposed
to the air had failed - cut it back a couple of inches and it was perfect.
Of course, that rubber might have perished quickly when exposed to air - I
didn't find out.

It needs replacing, no matter how difficult. It's almost certainly a fire
risk.

--
*Stable Relationships Are For Horses.

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

On Sun, 22 Aug 2004 22:19:25 +0000, Matthew Durkin wrote:

My Sister has just bought an old house pre-20th century house. We've found a
couple of mains cables running from the fusebox that have a lead sheath
(they looked just like the modern plastic ones until I scratched the paint
off and they revealed shiny lead.
Not sure yet where they run, but my hunch is the lighting circuits.
Getting them out will be very difficult (especially for my sister!)
What current would these be normally rated at?
Could they be dangerous - how can I tell?
Is there any way of safety testing them?
Any other comments?
Thanks,
Matthew

Wow - I saw some lead wiring 25 years ago and it was totally knackered
then. As someone else said, it's rubber insulated and the rubber perishes.
In theory it shouldn't be a shock risk as the sheath should be earthed
(but who can be sure) - but could definately be a fire risk (and a shock
risk if the earthing has failed).

Whilst it's *possibly* not going to blow up tomorrow or if it does,
it *should* just blow a fuse, do you want to take a known risk that
could have dire consequences?

Best get it looked at asap and definately turn the circuit off at the
fuseboard now. At the very least, do kill the circuit while people are
asleep or out of the house.

I'm not a qualified electrician, but I have some experience of diy wiring
(which I do by the book) and I've seen and occasionally replaced some
historical stuff.

Let's put it this way - I would *not* leave it on unsupervised with my
baby daughter in the house (ie, I might turn it on to prove what it
feeds, but only after getting everyone away from the area and taking
precautions myself). Sounds parnoid, but fire can start unseen and spread
fast, esp. if the wiring is under the floor or in the loft with lots of
dry flammable dust etc.

It would be safe to assume that the rubber has perished by now and what
you will probably have is hard brittle rubber tubes (or worse, crumbs)
being the only thing that is insulating anything from anything else.

WHATEVER YOU DO, DO NOT POKE IT, MOVE IT OR DISTURB IT IN ANY WAY - If it
has deteriorated, then it's likely to break down further and you'll get
a short (or electrocuted if the earth on the sheath has failed).

Mind you, if it does pass out as safe after inspection, you'll probably
have a world record!

The current rating - bit outside my limited experience, but IIRC 5A was
common at this sort of era for lighting circuits. Any seasoned
sparkies care to comment?

Best check the fuseboard too - does it look like an antique too? If so,
replace it at the same time.

Well - that's what I would do anyway, (I did say I'm not qualified :-o )


Best wishes,

Timbo

In article , Dave Plowman (News)
writes
In article ,
Matthew Durkin wrote:
My Sister has just bought an old house pre-20th century house. We've
found a couple of mains cables running from the fusebox that have a
lead sheath (they looked just like the modern plastic ones until I
scratched the paint off and they revealed shiny lead. Not sure yet
where they run, but my hunch is the lighting circuits. Getting them out
will be very difficult (especially for my sister!) What current would
these be normally rated at? Could they be dangerous - how can I tell? Is
there any way of safety testing them? Any other comments?

Most of the lighting wiring in my house was lead when I bought it, and it
was old then - about 30 years ago.

However, I was surprised to find that only the rubber insulation exposed
to the air had failed - cut it back a couple of inches and it was perfect.
Of course, that rubber might have perished quickly when exposed to air - I
didn't find out.

It needs replacing, no matter how difficult. It's almost certainly a fire
risk.


--
Frank Erskine

On Sun, 22 Aug 2004 23:53:45 +0100, Tim S wrote:

Wow - I saw some lead wiring 25 years ago and it was totally knackered
then.

Lead wiring is nothing..

I have seen junction boxes made from Oxo tins..the wires were brought
into the tins via holes punched in the sides, the wires twisted
together and the tin filled with bitumen or tar to act as an
insulator. (The wire had fabric over rubber insulation)

Scary, but rather ingenious!

sPoNiX

"Matthew Durkin" wrote in message ...
My Sister has just bought an old house pre-20th century house. We've found a
couple of mains cables running from the fusebox that have a lead sheath
(they looked just like the modern plastic ones until I scratched the paint
off and they revealed shiny lead.

Is there any way of safety testing them?

Pointless, they wont pass any tests.

Lead was generally earthed, but lead is soft so it is hard to grip
with much pressure, so the earthing joints may not be gas tight. And
as youve seen, lead corrodes in air. So it may not be earthed.

You wont need to worry about the exposed rubber insulation causing a
fire as it will probably all have fallen off decades ago. So dont move
the wire at all, not a bit.

The wiring will all be filthy by now: add the 2 above factors and its
very possible the lead may be sitting at something around 120v with
continuous leakage. Ditto everything connected to it.

Leakage degrades insulation, causing more leakage, causing more
degradation, causing hotspots causing charcoal that conducts fairly
well and causes fire.

With such old wiring I expect the only protection is wire fuses, which
would not stop any of the above in most cases.

Now you understand the problems. If only the lighting is on lead you
could disconnect it and use sockets for lights until its rewired. But
an installation like that in has to be thoroughly suspect in all
areas, and almost certainly long overdue for complete rewiring.

I dont know what your insurance co would do in the event of a fire,
whether theyd pay out, someone else may know.


Regards, NT

"N. Thornton" wrote in message
om...
"Matthew Durkin" wrote in message
...
My Sister has just bought an old house pre-20th century house. We've
found a
couple of mains cables running from the fusebox that have a lead sheath
snip

I dont know what your insurance co would do in the event of a fire,
whether theyd pay out, someone else may know.


WTF was the surveyor doing, or don't they look for this sort of problem
(considering that these wires are surface) ?

In article ,
:::Jerry:::: wrote:
WTF was the surveyor doing, or don't they look for this sort of problem
(considering that these wires are surface) ?

All the surveys I've ever seen say to get the wiring checked by a
specialist regardless. They tend to cover themselves...

--
*Virtual reality is its own reward *

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

"Matthew Durkin" wrote in message
...
My Sister has just bought an old house pre-20th century house. We've found
a
couple of mains cables running from the fusebox that have a lead sheath
(they looked just like the modern plastic ones until I scratched the paint
off and they revealed shiny lead.
Not sure yet where they run, but my hunch is the lighting circuits.
Getting them out will be very difficult (especially for my sister!)
What current would these be normally rated at?
Could they be dangerous - how can I tell?
Is there any way of safety testing them?
Any other comments?
Thanks,
Matthew



You should get some cash for the old cable if there's a fair bit of it. Try
your local friendly scrap metal dealer. Might help to pay for the new stuff.

Peter Scott

In article ,
Peter Scott wrote:
You should get some cash for the old cable if there's a fair bit of it.
Try your local friendly scrap metal dealer. Might help to pay for the
new stuff.

Not much, I'm afraid. Might cost more in petrol to get it there.

--
*If horrific means to make horrible, does terrific mean to make terrible?

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

"Dave Plowman (News)" wrote in message
...
In article ,
:::Jerry:::: wrote:
WTF was the surveyor doing, or don't they look for this sort of problem
(considering that these wires are surface) ?

All the surveys I've ever seen say to get the wiring checked by a
specialist regardless.

Agreed. They (the surveyors) usually state the above sentance in the (very)
small print.

I wonder if the lead cables running from the fuse box are connected to
anything. It is not uncommon to see the old cables, lead or otherwise still
present without them serving any purpose. Electricians can be too lazy to
remove the old stuff.

Adam

In article ,
ARWadsworth wrote:
I wonder if the lead cables running from the fuse box are connected to
anything. It is not uncommon to see the old cables, lead or otherwise still
present without them serving any purpose. Electricians can be too lazy to
remove the old stuff.

Heh heh - not just electricians. I'm in the process of replacing my
consumer unit which is at the top of the stairs going to the cellar, and
taking the opportunity to remove dead gas and water pipes and electrical
conduit. The gas iron barrel appears to be armour plated. ;-(

--
*Corduroy pillows are making headlines.

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

In article ,
Dave Plowman (News) wrote:
In article ,
ARWadsworth wrote:
I wonder if the lead cables running from the fuse box are connected to
anything. It is not uncommon to see the old cables, lead or otherwise still
present without them serving any purpose. Electricians can be too lazy to
remove the old stuff.

Heh heh - not just electricians. I'm in the process of replacing my
consumer unit which is at the top of the stairs going to the cellar, and
taking the opportunity to remove dead gas and water pipes and electrical
conduit. The gas iron barrel appears to be armour plated. ;-(

I fitted a new light in the living room a while back and when in the
bedroom above, noticed an old gas pipe! I've since lifted more floor
boards and see more of these little pipes. The attic is full of old
wiring and bakelite junction boxes. Fortunately none of it is in use as
the house was rewired in the last 15 years. (Quite creatively in places,
too)

The worrying thing was the scorch marks in the lath ceiling above the
ceiling rose ... I guess 100 years ago there was gas lighting and
perhaps it got a bit too hot on occasion...

Gordon

"sPoNiX" wrote in message
...
On Sun, 22 Aug 2004 23:53:45 +0100, Tim S wrote:

Wow - I saw some lead wiring 25 years ago and it was totally knackered
then.

Lead wiring is nothing..

I have seen junction boxes made from Oxo tins..the wires were brought
into the tins via holes punched in the sides, the wires twisted
together and the tin filled with bitumen or tar to act as an
insulator. (The wire had fabric over rubber insulation)

Scary, but rather ingenious!

sPoNiX

But were the wires 70 years old? That's really the problem here I think. I'm
sure they were good new, and the fact they're still here is testimony (one
assumes) to the original quality; but the materials are perishable!
Thanks for the advice all. I'm going to give my Dad a call and advise he
gets he arse round there pronto to sort something out! I'll get him to save
whatever he pulls out so I can have a look and see if there really was
anything to worry about after all!
Matt

"Dave Plowman (News)" wrote in message
...
In article ,
ARWadsworth wrote:
I wonder if the lead cables running from the fuse box are connected to
anything. It is not uncommon to see the old cables, lead or otherwise
still
present without them serving any purpose. Electricians can be too lazy
to
remove the old stuff.

Heh heh - not just electricians. I'm in the process of replacing my
consumer unit which is at the top of the stairs going to the cellar, and
taking the opportunity to remove dead gas and water pipes and electrical
conduit. The gas iron barrel appears to be armour plated. ;-(


Heh, I remember when we re-wired our (old family) 1901 house back in the
late 1960's, on lifting floor boards it was obvious that the house had been
plumbed for gas lighting (but was never used), there were 3 generations of
electric light and power [1] plus 2 generations of servant call bells [2] -
all still in place although very much not ready for use anymore, if ever it
had been by the then current standards !

The house was built for and by an architect for his own use and thus he
incorporated many up and coming novelties, it was the only house in the road
that didn't have a caller and a central stair well for the 3 floors and it
had electric power from the outset (one of the first in the town IIRC) but
was plumbed for gas in case that new thing called 'electric-light' didn't
catch on...

The biggest surprise was finding letters and (lets call it) other stuff
relating to the family of a former Chaplin to the Bows-Lyon family, as the
'guilty' and or any off-spring might have still been living at the time my
father thought the best policy was to burn the evidence !

It really is amazing what can be found under floor boards and in the eves of
older property....

[1] the first was bare wire and insulation block...

[2] this included such things like pulley wheels and bell cranks.

On Mon, 23 Aug 2004 19:14:36 GMT, "Matthew Durkin"
wrote:

But were the wires 70 years old? That's really the problem here I think. I'm
sure they were good new, and the fact they're still here is testimony (one
assumes) to the original quality; but the materials are perishable!
Thanks for the advice all. I'm going to give my Dad a call and advise he
gets he arse round there pronto to sort something out! I'll get him to save
whatever he pulls out so I can have a look and see if there really was
anything to worry about after all!
Matt

Hi,

Might be worth checking for continuity between the sheath and earth at
both ends then testing them with a Megger. If an RCD is then added
that would give _some_ protection.

cheers,
Pete.

In article , chris French
writes

Yes, it would be worried about the insulation inside this cable which is
likely to be rubber - or rather I'd be worried about the insulation at
the ends of the cable where it terminates.

In our old house the cores were wrapped in waxed paper, not rubber,
inside the lead sheath. Joints were made by soldering the wires
together, insulating them with tape, and then wrapping a sheet of lead
around the joint and soldering it to the sheath of the wires entering
the joint. (for example, joints with three wires resulted in a
triangular lead "blob" soldered to the three incoming wires.) Quite a
work of art, but bloody frightening to still see used in this day and
age. And people used to run irons and things off the light sockets
using this wiring...

--
..sigmonster on vacation

In article ,
Matthew Durkin wrote:
As for the sheath being at 120V - doubt it. I didn't get any kind of
shock, mild tingle etc when I scratched a bit of paint off the surface
to reveal the metal last week. The metal was also very shiny and not in
any way corroded. The cable was also stone cold, so not running warm at
all.

It'll probably be fine until disturbed. But in a 'new' house, people tend
to want to fit new lights, switches dimmers etc. That's when the fun
starts.

--
*If you try to fail, and succeed, which have you done?

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

"Dave Plowman (News)" wrote in message
...
In article ,
ARWadsworth wrote:
I wonder if the lead cables running from the fuse box are connected to
anything. It is not uncommon to see the old cables, lead or otherwise
still
present without them serving any purpose. Electricians can be too lazy to
remove the old stuff.

Heh heh - not just electricians. I'm in the process of replacing my
consumer unit which is at the top of the stairs going to the cellar, and
taking the opportunity to remove dead gas and water pipes and electrical
conduit. The gas iron barrel appears to be armour plated. ;-(

--
*Corduroy pillows are making headlines.

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

I forgot to mention something. In 2003 an electrician added 4 downlighters
to the circuit when the bathroom was re-done, and has left his safety tested
sticker on the fusebox. My Dad reckons that the original 5 Amp round pin
wall sockets would have been connected to it, and that the 13A modern
sockets may well all be on it. He could only see the one obvious cable
running upstairs.
As for the sheath being at 120V - doubt it. I didn't get any kind of shock,
mild tingle etc when I scratched a bit of paint off the surface to reveal
the metal last week. The metal was also very shiny and not in any way
corroded. The cable was also stone cold, so not running warm at all.
Anyway, I think my Dad's going round there next week to test the cables and
see if there is an imminent problem. I think we might tackle a re-wire over
Christmas unless the results of the cable test indicate a more pressing
need. In the meantime, we'll be advising my sister to not use a hairdryer,
kettle etc upstairs.

In message , Peter Scott
writes

"Matthew Durkin" wrote in message
...
My Sister has just bought an old house pre-20th century house. We've found
a
couple of mains cables running from the fusebox that have a lead sheath
(they looked just like the modern plastic ones until I scratched the paint
off and they revealed shiny lead.
Not sure yet where they run, but my hunch is the lighting circuits.
Getting them out will be very difficult (especially for my sister!)
What current would these be normally rated at?
Could they be dangerous - how can I tell?
Is there any way of safety testing them?
Any other comments?
Thanks,
Matthew



You should get some cash for the old cable if there's a fair bit of it. Try
your local friendly scrap metal dealer. Might help to pay for the new stuff.

Prolly enough for a pint of beer (or two)
--
geoff

"Mike Tomlinson" wrote in message
...
In article , chris French
writes

Yes, it would be worried about the insulation inside this cable which is
likely to be rubber - or rather I'd be worried about the insulation at
the ends of the cable where it terminates.

In our old house the cores were wrapped in waxed paper, not rubber,
inside the lead sheath. Joints were made by soldering the wires
together, insulating them with tape, and then wrapping a sheet of lead
around the joint and soldering it to the sheath of the wires entering
the joint. (for example, joints with three wires resulted in a
triangular lead "blob" soldered to the three incoming wires.) Quite a
work of art, but bloody frightening to still see used in this day and
age. And people used to run irons and things off the light sockets
using this wiring...

--
.sigmonster on vacation



My Dad seemed to think it would be paper insulated, not rubber. Apparently
it lasts a long time so long as it is never allowed to get damp. Not seen
any lead blobs though! There are definitely lead junction boxes in this
installation...

On Mon, 23 Aug 2004 22:44:16 +0000, Matthew Durkin wrote:


My Dad seemed to think it would be paper insulated, not rubber. Apparently
it lasts a long time so long as it is never allowed to get damp. Not seen
any lead blobs though! There are definitely lead junction boxes in this
installation...

Pretty sure I've seen rubber - but it was a looong time ago. I suppose if
there were a rubber version, the sheath would have to have been wrapped
around cold and an unjoined seam left. Was there such a thing or have I
smoked too many mushrooms? - not much chance of seam welding lead in
contact with rubber I would have thought. Or was there a magical way of
cold drawing a lead sheath tight around the cores during manufacture?

The paper variety would make sense - a larger version was the standard for
supply cables underground. Still plenty of it in service in London - saw a
lump being replaced 2 years in Sutton just outside the station. Obviously
wasn't very serviceable at the end due to the number of times the lights
went out in the upper High Street(!).

Cheers

Timbo

On Mon, 23 Aug 2004 21:59:39 GMT, "Matthew Durkin"
strung together this:

I forgot to mention something. In 2003 an electrician added 4 downlighters
to the circuit when the bathroom was re-done, and has left his safety tested
sticker on the fusebox.

Somewhere there'll be a long list of failures if it really has been
tested properly.
--

SJW
A.C.S. Ltd

In article , Mike Tomlinson
writes

In our old house the cores were wrapped in waxed paper, not rubber,
inside the lead sheath. Joints were made by soldering the wires
together, insulating them with tape, and then wrapping a sheet of lead
around the joint and soldering it to the sheath of the wires entering
the joint. (for example, joints with three wires resulted in a
triangular lead "blob" soldered to the three incoming wires.) Quite a
work of art, but bloody frightening to still see used in this day and
age.

Why's that? Is electricity any more dangerous now than it was then?

:-)
--
Frank Erskine

"Matthew Durkin" wrote in message ...
"Dave Plowman (News)" wrote in message
...
In article ,

I forgot to mention something. In 2003 an electrician added 4 downlighters
to the circuit when the bathroom was re-done, and has left his safety tested
sticker on the fusebox. My Dad reckons that the original 5 Amp round pin
wall sockets would have been connected to it, and that the 13A modern
sockets may well all be on it. He could only see the one obvious cable
running upstairs.
As for the sheath being at 120V - doubt it. I didn't get any kind of shock,
mild tingle etc when I scratched a bit of paint off the surface to reveal
the metal last week. The metal was also very shiny and not in any way
corroded.

Lead does not stay bright in air. When you took the paint off you took
the corrosion off with it.

The cable was also stone cold, so not running warm at all.

sounds like you didnt understand what was said on that point.


Anyway, I think my Dad's going round there next week to test the cables and
see if there is an imminent problem. I think we might tackle a re-wire over
Christmas unless the results of the cable test indicate a more pressing
need. In the meantime, we'll be advising my sister to not use a hairdryer,
kettle etc upstairs.

Your Darwin Award has been reserved for you.


NT

"N. Thornton" wrote in message
om...
snip

Lead does not stay bright in air. When you took the paint off you took
the corrosion off with it.

Err. so there was air under the paint and thus corrosion, what is the point
of paint then ? There was not corrosion because the paint had kept the air
from the surface of the lead, as it's designed to do !...

Matthew Durkin wrote:
My Sister has just bought an old house pre-20th century house. We've found a
couple of mains cables running from the fusebox that have a lead sheath
(they looked just like the modern plastic ones until I scratched the paint
off and they revealed shiny lead.
Not sure yet where they run, but my hunch is the lighting circuits.
Getting them out will be very difficult (especially for my sister!)
What current would these be normally rated at?
Could they be dangerous - how can I tell?
Is there any way of safety testing them?
Any other comments?
Thanks,
Matthew



This wiring may have been installed in the 50s or earlier. I remember
watching it being installed in my grandparents house. We had to
completely rewire when we took over the house in 2000.
Typically the outer case is soft lead and the inner insulation is rubber.
When air gets at it the rubber is liable to perish. It then becomes
hard, brittle and prone to crumble, reducing its effectiveness as an
insulator.

What could you do with it?
1. Do not disturb. Ie. do not touch, move, change any light fittings or
switches etc ... and hope it lasts until you can replace it.
Clearly, not a long term solution! But any disturbance will aggrevate
the problem.
2. Get it tested. You are almost certain to be told its had it. But
you really want to know is if any of the circuits have lowered
resistance when all switches are off. Any small current leakage would be
a sign of trouble building up and will only get worse.
3. Rewire - to meet today's needs, which are likely to be different from
those of 50 years ago.. Leave the old stuff in place - just disconnect
it all.

Is it just the lighting circuits that are lead coated?
What is the the state of the power socket wire? They might be a
different type of cable - with itsa own problems.


David H-S

On Mon, 23 Aug 2004 23:53:42 +0100, Tim S wrote:

On Mon, 23 Aug 2004 22:44:16 +0000, Matthew Durkin wrote:


My Dad seemed to think it would be paper insulated, not rubber. Apparently
it lasts a long time so long as it is never allowed to get damp. Not seen
any lead blobs though! There are definitely lead junction boxes in this
installation...

Pretty sure I've seen rubber - but it was a looong time ago. I suppose if
there were a rubber version, the sheath would have to have been wrapped
around cold and an unjoined seam left. Was there such a thing or have I
smoked too many mushrooms? - not much chance of seam welding lead in
contact with rubber I would have thought. Or was there a magical way of
cold drawing a lead sheath tight around the cores during manufacture?

I have a piece here, that I had kicking around and have just disected it
out of interest.
The inner insulation is definitely rubber, still in good condition and
flexible. This piece was not connected anything when I found it and was cut
back so other than the cut end, the rubber wasn't exposed.
No sign of any visible seam on the lead sheath, inside or out.
After pulling the wires out of the sheath, the following is printed on the
insulation of the live:
"... 250 VOLT CMA (REGD) BRITISH INSULATED CALLENDERS CABLES LIMITED LEIGH
AND HELSBY ENGLAND..."
The conducters have 3 strands of copper each, not sure about size.

":::Jerry::::" wrote in message ...
"N. Thornton" wrote in message
om...
snip

Lead does not stay bright in air. When you took the paint off you took
the corrosion off with it.

Err. so there was air under the paint and thus corrosion, what is the point
of paint then ? There was not corrosion because the paint had kept the air
from the surface of the lead, as it's designed to do !...

Possibly, though we cant simply assume that option. Any case, the
earth bond can not be assumed to be gas tight.

what is the point of paint then ?

I assumed decorative, do you think there is a different purpose?

NT

In article , John Armstrong
writes

"... 250 VOLT CMA (REGD) BRITISH INSULATED CALLENDERS CABLES LIMITED LEIGH
AND HELSBY ENGLAND..."

The BICC plant at Helsby is still going.

--
..sigmonster on vacation

On Tue, 24 Aug 2004 18:42:54 +0100, John Armstrong wrote:

"... 250 VOLT CMA (REGD) BRITISH INSULATED CALLENDERS CABLES LIMITED LEIGH
AND HELSBY ENGLAND..."
The conducters have 3 strands of copper each, not sure about size.

Hmm - I should ask my Dad - he did a stint with Callenders (before BI
merged I think). They had a most cool 1 MV test rig for insulation testing
- on big insulators right up in the air apparantly.

"N. Thornton" wrote in message
om...
":::Jerry::::" wrote in message
...
"N. Thornton" wrote in message
om...
snip

Lead does not stay bright in air. When you took the paint off you took
the corrosion off with it.

Err. so there was air under the paint and thus corrosion, what is the
point
of paint then ? There was not corrosion because the paint had kept the
air
from the surface of the lead, as it's designed to do !...

Possibly, though we cant simply assume that option. Any case, the
earth bond can not be assumed to be gas tight.

No argument there, I was just questioning your reasoning behind the paint
remark.


what is the point of paint then ?

I assumed decorative, do you think there is a different purpose?


Decorative is a secondary function, protection is the prime function, even
though it's not always used as such IYSWIM.

":::Jerry::::" wrote in message
...

"N. Thornton" wrote in message
om...
":::Jerry::::" wrote in message
...
"N. Thornton" wrote in message
om...
snip

Lead does not stay bright in air. When you took the paint off you
took
the corrosion off with it.

Err. so there was air under the paint and thus corrosion, what is the
point
of paint then ? There was not corrosion because the paint had kept the
air
from the surface of the lead, as it's designed to do !...

Possibly, though we cant simply assume that option. Any case, the
earth bond can not be assumed to be gas tight.

No argument there, I was just questioning your reasoning behind the paint
remark.


what is the point of paint then ?

I assumed decorative, do you think there is a different purpose?


Decorative is a secondary function, protection is the prime function, even
though it's not always used as such IYSWIM.



In an unused cellar I don't think the paint was there for decorative
purposes.

Also - I understand fully all the points that have been made on this forum,
especially the ones regarding carbon build up around where insulation is
breaking down etc. My point about the cable being cold was merely
observational!

point taken about the darwin award. I hope it doesn't come to that. I live
250 miles from my sister, and my dad works 12 hour shifts plus 2 hours
travelling. He's also got his floor up at the moment treating woodworm.
There's only so much we can do!

I think one of the most interesting things to come out of this long
discussion is that those who actually have some of this cable have it in
good condition. There are no sings of any decomposition of the cable at all
in this installation. I'm not saying it's good. But it has been running
fault free for maybe 70 years.
My Dad will be over at my sisters with a megger asap to see if there's any
imminent danger, and he'll also be ripping out the lead cellar lighting.
There will still be the laed feed into the house itself though, but at least
then we'll be in a better position to know how bad it is!

"David H-S" wrote in message
...
Matthew Durkin wrote:
My Sister has just bought an old house pre-20th century house. We've
found a couple of mains cables running from the fusebox that have a lead
sheath (they looked just like the modern plastic ones until I scratched
the paint off and they revealed shiny lead.
Not sure yet where they run, but my hunch is the lighting circuits.
Getting them out will be very difficult (especially for my sister!)
What current would these be normally rated at?
Could they be dangerous - how can I tell?
Is there any way of safety testing them?
Any other comments?
Thanks,
Matthew



This wiring may have been installed in the 50s or earlier. I remember
watching it being installed in my grandparents house. We had to
completely rewire when we took over the house in 2000.
Typically the outer case is soft lead and the inner insulation is rubber.
When air gets at it the rubber is liable to perish. It then becomes hard,
brittle and prone to crumble, reducing its effectiveness as an insulator.

What could you do with it?
1. Do not disturb. Ie. do not touch, move, change any light fittings or
switches etc ... and hope it lasts until you can replace it.
Clearly, not a long term solution! But any disturbance will aggrevate the
problem.
2. Get it tested. You are almost certain to be told its had it. But you
really want to know is if any of the circuits have lowered resistance when
all switches are off. Any small current leakage would be a sign of trouble
building up and will only get worse.
3. Rewire - to meet today's needs, which are likely to be different from
those of 50 years ago.. Leave the old stuff in place - just disconnect it
all.

Is it just the lighting circuits that are lead coated?
What is the the state of the power socket wire? They might be a different
type of cable - with itsa own problems.


David H-S

Thanks David - nice to have some sensible suggestoins! We'll be doing what
you said and rewiring as soon as we have a chance!

On Sun, 22 Aug 2004 22:19:25 GMT, Matthew Durkin wrote:

My Sister has just bought an old house pre-20th century house. We've found a
couple of mains cables running from the fusebox that have a lead sheath
(they looked just like the modern plastic ones until I scratched the paint
off and they revealed shiny lead.
Not sure yet where they run, but my hunch is the lighting circuits.
Getting them out will be very difficult (especially for my sister!)
What current would these be normally rated at?
Could they be dangerous - how can I tell?
Is there any way of safety testing them?
Any other comments?
Thanks,
Matthew

The insulation will almost certainly be butyl rubber. It has a tendency
to degrade seriously where it is exposed to air, i.e. at all joints,
switches, plugs, etc. and becomes brittle, crumbly, and powdery. Cut a
length in half and you'll probably find the insulation is perfect! There
can also be problems with earth continuity.

Butyl rubber was a common insulant within the electricity supply
industry 60 to 70 years ago, used for lead-in cables to properties. Much
has been replaced, although it still turns up in predominantly rural
locations.

Lead sheathed cable is now considered to be unsafe for electrical
installation work, and should be replaced ASAP.

--
wanderer at tesco dot net

In article ,
Matthew Durkin wrote:
In an unused cellar I don't think the paint was there for decorative
purposes.

Well, lead is commonly used for roof flashings etc and isn't painted, so I
can't see any reason to paint it inside. It sort of oxidises on the
surface and this acts as a protection for the rest anyway.

Also - I understand fully all the points that have been made on this
forum, especially the ones regarding carbon build up around where
insulation is breaking down etc. My point about the cable being cold
was merely observational!

point taken about the darwin award. I hope it doesn't come to that. I
live 250 miles from my sister, and my dad works 12 hour shifts plus 2
hours travelling. He's also got his floor up at the moment treating
woodworm. There's only so much we can do!

Then get in a pro?

I think one of the most interesting things to come out of this long
discussion is that those who actually have some of this cable have it in
good condition. There are no sings of any decomposition of the cable at
all in this installation. I'm not saying it's good. But it has been
running fault free for maybe 70 years. My Dad will be over at my
sisters with a megger asap to see if there's any imminent danger, and
he'll also be ripping out the lead cellar lighting. There will still be
the laed feed into the house itself though, but at least then we'll be
in a better position to know how bad it is!

You need to do a physical inspection of the ends at a switch etc and check
if the rubber insulation is perished - and I'll bet it is. An insulation
test may not show this up, though.

It's probably 50 years old plus.

--
*There are two kinds of pedestrians... the quick and the dead.

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

"Matthew Durkin" wrote in message ...

Also - I understand fully all the points that have been made on this forum,
especially the ones regarding carbon build up around where insulation is
breaking down etc. My point about the cable being cold was merely
observational!

its bound to be cold, once it gets to the stage of heating up there
would likely be a fire within hours.

point taken about the darwin award. I hope it doesn't come to that. I live
250 miles from my sister, and my dad works 12 hour shifts plus 2 hours
travelling. He's also got his floor up at the moment treating woodworm.
There's only so much we can do!

I think one of the most interesting things to come out of this long
discussion is that those who actually have some of this cable have it in
good condition. There are no sings of any decomposition of the cable at all
in this installation. I'm not saying it's good. But it has been running
fault free for maybe 70 years.

You cant assume its fault free, I think its more likely there are
leakage currents running here there and everywhere. On a 5A wire fused
circuit you would have to have more than 1.2kW dissipated by the cable
for a long time (like an hour plus) before the fuses would start to
think about blowing.

My Dad will be over at my sisters with a megger asap to see if there's any
imminent danger, and he'll also be ripping out the lead cellar lighting.
There will still be the laed feed into the house itself though, but at least
then we'll be in a better position to know how bad it is!

Right. If youre truly unable to do the work you could buy a reel of
flex and a few sockets and get yourself electricity to the rooms that
way. Crude, but if it were me I would not want to be running mains
down that old stuff, not for a minute. I think this would be much
better use of a couple of hours than trying to megger the
installation, when it cant have more than 1% chance of passing.

Even by 1930s standards an installation like this would be condemned.


Regards, NT