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

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

"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.

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 , 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

"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

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

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

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

"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

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 ,
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.

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

"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.

"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.

"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.

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

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

"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!

This discussion has been about lead wiring.

Another type of cable sometimes used c. 50 years ago for ring mains
consisted of a copper sheath, a ceramic insulator and then the live and
neutral leads inside that, cased I thinkk in rubber. The whole about
1/3 inch in diameter.
while lead cable was used for lighting in our house, this copper/ceramic
cable was used for the ringmain power crcuits in our old house. I think
it was installed in the late 50s for my parents.

What we saw by 2000 was increasing incidents of short circuits (via the
copper exterior) and blown fuses. Eventually whole circuits became
unusable. Regular slight movements, duw to floor boards & joists
flexing as people moved about, had caused the ceramic to crumble. then
maybe some damp penetrated and shorts were the result.

This was eventually one of the final things that led us to persuade
widowed mother in her late 80s that the house was no longer safe for
her, poor lady.
The week after a major furniture moving exercise which obiously
disturbed floor boards even more, the entire kitchen circuit packed up.

So in 2000 we took over and had to replace the lot immediately.

Of course if you have to live with it for a short while, the advice
about not disturbing it applies to this just as for the lead cables.

So, Matt, do you have any cable like that in your ring mains?

David H-S

"David H-S" wrote in message
...
This discussion has been about lead wiring.

Another type of cable sometimes used c. 50 years ago for ring mains
consisted of a copper sheath, a ceramic insulator and then the live and
neutral leads inside that, cased I thinkk in rubber. The whole about
1/3 inch in diameter.
snip

MICC cable ?

In article ,
David H-S writes:
This discussion has been about lead wiring.

Another type of cable sometimes used c. 50 years ago for ring mains
consisted of a copper sheath, a ceramic insulator and then the live and
neutral leads inside that, cased I thinkk in rubber. The whole about
1/3 inch in diameter.

I think you are describing MICC (Mineral Insulated Copper Covered)
cable, or Pyro to use one of the trade names.

while lead cable was used for lighting in our house, this copper/ceramic
cable was used for the ringmain power crcuits in our old house. I think
it was installed in the late 50s for my parents.

What we saw by 2000 was increasing incidents of short circuits (via the
copper exterior) and blown fuses. Eventually whole circuits became
unusable. Regular slight movements, duw to floor boards & joists
flexing as people moved about, had caused the ceramic to crumble. then
maybe some damp penetrated and shorts were the result.

It lasts forever providing the ends are sealed against any
moisture ingress and the copper sheath doesn't get punctured.
I guess frequent movement could cause work-hardening and eventual
fracture of the copper sheath.

The insulation is magnesium oxide, which is hygroscopic (will
absorb water from the air given the chance), hence the need to
make sure the cable ends are well made.

MICC will survive being heated up to just short of copper's
melting point, and you can hammer a piece almost flat and it
will still be fine (providing you don't puncture the sheath),
as the conductors and compressed magnesium oxide all deform
in exactly the same proportion. Indeed, the stuff is all
initially made much thicker, and taken down to the required
final thickness by running it through pressure rollers.
It is still used today in situations where any of its outstanding
physical properties are required, but it is expensive and
installing it is a rather more specialist task. This and its
tendancy to absorb water into the insulation are its weak
points. Also, it doesn't handle voltage spikes from inductive
load switching well -- this isn't an issue today, but it was a
problem when fluorescent lamps first started appearing and
fast-break switches were still around (which were required
for earlier DC circuits).

--
Andrew Gabriel

In article ,
David H-S wrote:
Another type of cable sometimes used c. 50 years ago for ring mains
consisted of a copper sheath, a ceramic insulator and then the live and
neutral leads inside that, cased I thinkk in rubber. The whole about
1/3 inch in diameter.
while lead cable was used for lighting in our house, this copper/ceramic
cable was used for the ringmain power crcuits in our old house. I think
it was installed in the late 50s for my parents.

What we saw by 2000 was increasing incidents of short circuits (via the
copper exterior) and blown fuses. Eventually whole circuits became
unusable. Regular slight movements, duw to floor boards & joists
flexing as people moved about, had caused the ceramic to crumble. then
maybe some damp penetrated and shorts were the result.

You've not understood MICC cable. The insulator is already a powder so
can't crumble.

If it was properly installed, it must have been damaged in some way and
let moisture in - that's the only thing that eventually kills it.

A totally different and longer lasting product than lead sheathed - and
indeed one which is still very much in use for hazardous applications.

--
*If at first you don't succeed, avoid skydiving.*

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

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

"wanderer" wrote in message
...

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.

I'd guess that at least third to a half of all the houses in the country
still have lead-sheathed paper or PBJ insulated service cables. The supply
industry doesn't seem to be in any hurry to replace them.

--
Andy

"Andy Wade" wrote in message
...
"wanderer" wrote in message
...

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.

I'd guess that at least third to a half of all the houses in the country
still have lead-sheathed paper or PBJ insulated service cables. The
supply
industry doesn't seem to be in any hurry to replace them.

--
Andy



someone else commented on such cables being replaced on the Sutton
streetlights last year. I guess the difference is if they blow up
underground they don't really do much damage, whereas in a house they can be
a real fire hazard. So no real drive (other than presumably leakage) to
replace those underground.
It is sounding like they are more common that I'd have thought given some of
the postings on this thread! not that this is a good thing of course!!
amazing they actually keep going this long, despite the obvious dangers.
Matt

In article ,
Andy Wade wrote:
I'd guess that at least third to a half of all the houses in the country
still have lead-sheathed paper or PBJ insulated service cables. The
supply industry doesn't seem to be in any hurry to replace them.

But the ends of these tend to be sealed?

--
*Real men don't waste their hormones growing hair

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

"Dave Plowman (News)" wrote in message
...

But the ends of these tend to be sealed?

Yes (hopefully). For street cables I think most failures are the result of
water getting in due to faulty sealing of joints or mechanical damage.

--
Andy