When houses have their 240V mains supply delivered by overhead wires (eg on
wooden poles) in the street, rather than being fed underground to each
house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

I'm talking about the older wiring where there are three separate wires,
rather than the upgraded wiring where there is a twisted bundle of three
wires (or four if there is also a neutral). Obviously in the latter case the
wires in the bundle will need to be insulated.

NY wrote:

When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to
each house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

I think they're uninsulated. Based on a) their general green verdigris
tinge and b) the fact that when building works takes place, the DNO will
install temporary sleeving over them.

Some were some not. Its all a bit debatable but I'd have thought the ones
into the house were insulated from memory of such a building we rented for a
holiday .

Why do you ask?
Brian

--
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This newsgroup posting comes to you directly from...
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Blind user, so no pictures please
Note this Signature is meaningless.!
"NY" wrote in message
.. .
When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to each
house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

I'm talking about the older wiring where there are three separate wires,
rather than the upgraded wiring where there is a twisted bundle of three
wires (or four if there is also a neutral). Obviously in the latter case
the wires in the bundle will need to be insulated.

On Monday, July 9, 2018 at 9:20:27 AM UTC+1, NY wrote:
When houses have their 240V mains supply delivered by overhead wires (eg on
wooden poles) in the street, rather than being fed underground to each
house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

I'm talking about the older wiring where there are three separate wires,
rather than the upgraded wiring where there is a twisted bundle of three
wires (or four if there is also a neutral). Obviously in the latter case the
wires in the bundle will need to be insulated.

Usually not insulated. Even as far as the insulators on the side of the house sometimes (mums bungalow was wired this way). Five wires so presumably N, L1, L2, L3 and street lighting?

Philip

On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to
each house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

I'm talking about the older wiring where there are three separate wires,
rather than the upgraded wiring where there is a twisted bundle of three
wires (or four if there is also a neutral). Obviously in the latter case
the wires in the bundle will need to be insulated.

Usually uninsulated.

NY wrote

When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to each
house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

With mine, the wires down the street on the poles arent insulated,
but the 4 wires from the pole to the mains fuses on the bargeboard
of my house are insulated and twisted together. I have a two phase
supply to the house because I have an off peak storage heater that
I no longer use, and they use a single 4 wire cable to the houses
when more than one phase is supplied to the house and just don’t
use the spare 4th wire.

I'm talking about the older wiring where there are three separate wires,
rather than the upgraded wiring where there is a twisted bundle of three
wires (or four if there is also a neutral). Obviously in the latter case
the wires in the bundle will need to be insulated.

"Huge" wrote in message
...
Our last house was supplied overhead through fields. 240V from a pole
pig several hundred yards away. Originally the wires were uninsulated
and about a foot apart.

I first suspected that they were uninsulated when a lad at school threw a
metal coathanger at the overhead wires that ran along the road outside the
school. There was a bright flash and the coathanger fell down with a huge
nick melted out of the metal. Up until then I'd always assumed that "all"
wires were insulated. It was the first time I'd seen overhead 240V cables:
all the houses I've lived in apart from the most recent had underground
mains.

I wonder how many people would work close to the point where the wires
attach to the insulators on the house (eg when painting the house) if they
knew that the wires were uninsulated and therefore liable to give you a
nasty shock if you touch the live one.

Our last house was one of several terraces each of three houses. All of them
were fed from a single feed from the road, with a single multi-core cable
stapled all along the back of the house and then a short length of three
separate (uninsulated?) wires over the driveway between one terrace and the
next. Since there were three wires from the road, I presume different houses
were fed from different phases, rather than all of them from the same phase.

We had to have several poles replaced because
The most impressive thing was the UniMog 6x6 pole handling machine - one
guy just "drilled" a hole in the ground and pushed the pole into it. Took
about 2 minutes per pole. They just chainsawed the old ones off (and I
kept them - one subsequently made a very good gatepost). Despite being
over 40 years old, they still smelled of creosote when cut.

Back in the days when creosote was *real* creosote before the H&S brigade
"watered it down". I'm not sure what the modern replacement is for creosote,
when treating wood to make it non-rotting.


I watched the electricity company replacing the wooden poles and 11 kV to
240V pole-mounted transformer opposite our house. The old transformer was
mounted on a single pole, but they replaced it with a new, smaller on,
though mounted on two poles a foot apart. The power was only off for about
half an hour, so they worked quickly. I always wondered how often they used
those pole-mounted switches, operated with the sort of rod that is used to
open high windows in a school hall. I imagine that was a prime example: to
be able to isolate the 11 kV feed somewhere upstream while they replaced the
transformer.

Now I bet if you threw a coathanger at the 11 kV wires that cross the field,
you'd get more than a little flash. Mind you, I'm sure the wires are spaced
a bit more widely than the length of a coathanger.

On 09/07/2018 10:12, Tufnell Park wrote:
On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires
(eg on wooden poles) in the street, rather than being fed underground
to each house, are the three phase wires (and the two wires to each
house) insulated, or are they simply prevented from shorting by the
spacing of them?

I'm talking about the older wiring where there are three separate
wires, rather than the upgraded wiring where there is a twisted bundle
of three wires (or four if there is also a neutral). Obviously in the
latter case the wires in the bundle will need to be insulated.

Usually uninsulated.

I thought the more modern ones were usually insulated. They still
(wisely) put canvas sleeves on them if scaffolding goes up nearby.

On 09/07/18 11:14, NY wrote:

Now I bet if you threw a coathanger at the 11 kV wires that cross the
field, you'd get more than a little flash. Mind you, I'm sure the wires
are spaced a bit more widely than the length of a coathanger.

Not totally a given - the trips on 11kV (I was told by my dad with was
an LEB engineer) wer eusually more sensitive than low voltage, the
latter being set to try to blow a fault clear rather than trip if possible.

On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to
each house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

I'm talking about the older wiring where there are three separate wires,
rather than the upgraded wiring where there is a twisted bundle of three
wires (or four if there is also a neutral). Obviously in the latter case
the wires in the bundle will need to be insulated.

Between the poles, usually uninsulated IME. However the pole to house
drop can be either - but often has at least the live insulated.



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 09/07/2018 11:16, newshound wrote:
On 09/07/2018 10:12, Tufnell Park wrote:
On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires
(eg on wooden poles) in the street, rather than being fed underground
to each house, are the three phase wires (and the two wires to each
house) insulated, or are they simply prevented from shorting by the
spacing of them?

I'm talking about the older wiring where there are three separate
wires, rather than the upgraded wiring where there is a twisted
bundle of three wires (or four if there is also a neutral). Obviously
in the latter case the wires in the bundle will need to be insulated.

Usually uninsulated.

I thought the more modern ones were usually insulated. They still
(wisely) put canvas sleeves on them if scaffolding goes up nearby.

The wires described by the OP will be uninsulated (vertically separated).

The modern method is to use aerial bundled insulated cables which are in
twisted formation but many of the former type are still in the majority.

On 09/07/2018 11:14, NY wrote:
....
I wonder how many people would work close to the point where the wires
attach to the insulators on the house (eg when painting the house) if
they knew that the wires were uninsulated and therefore liable to give
you a nasty shock if you touch the live one.

You should, of course, contact the supplier and have the wires sleeved
before working near them. IME it takes them about four weeks to get
around to doing it. However, as they don't bother to take it away
afterwards, the wires to my house now have yellow sleeves around them


--
--

Colin Bignell

On 09/07/2018 11:16, newshound wrote:
....
I thought the more modern ones were usually insulated. They still
(wisely) put canvas sleeves on them if scaffolding goes up nearby.

Which my supplier put up using scaffolding as they couldn't get their
cherry picker in close enough to the house.

--
--

Colin Bignell

On Mon, 9 Jul 2018 01:55:35 -0700 (PDT), wrote:

When houses have their 240V mains supply delivered by overhead
wires
(eg on wooden poles) in the street,

Or field... our supply from pole to house was two wires spaced about
6" apart vertically. The top, live, was insulated, the bottom,
combined neutral/earth wasn't. This has since been replaced with a
length of 35 mm^2 coaxial which is inulated.

Usually not insulated. Even as far as the insulators on the side of the
house sometimes (mums bungalow was wired this way). Five wires so
presumably N, L1, L2, L3 and street lighting?

More likely earth. Can't see why you'd need a seperate street
lighting supply, each lamp has it's own timeswitch or more likely
photocell to turn 'em on/off. At least for ordinary streets, major
roads and motoroways have switched circuits.

--
Cheers
Dave.

On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to
each house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

Some rural places may never have been insulated others did have
insulation but all that remains now are a few remnants here and there.

Typically in that configuration the 240v mains on vertical layout starts
out insulated but after a while the elements and UV take its toll. Then
strips of old insulation come free and swing about in the breeze. In a
good storm we used to get lots of arcing and sparking as adjacent wires
were shorted together with wet slightly carbonised "insulation".

The failing cables were eventually replaced with a single steel cored
tri-phase aluminium conductor which is very insulated and amazingly can
almost support the weight of a tree across it.

The poles failed before the cable did.

HT horizontal configuration and EHT is not usually not insulated.

I'm talking about the older wiring where there are three separate wires,
rather than the upgraded wiring where there is a twisted bundle of three
wires (or four if there is also a neutral). Obviously in the latter case
the wires in the bundle will need to be insulated.

They start out insulated but after a while all bets are off. They will
still work OK without insulation unless you happen to touch one.

--
Regards,
Martin Brown

On Mon, 9 Jul 2018 20:14:04 +1000, cantankerous geezer Rot Speed blabbered,
again:

When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to each
house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

With mine, the wires down the street on the poles arent insulated,
but the 4 wires from the pole to the mains fuses on the bargeboard
of my house are insulated and twisted together. I have a two phase
supply to the house because I have an off peak storage heater that
I no longer use, and they use a single 4 wire cable to the houses
when more than one phase is supplied to the house and just don¢t
use the spare 4th wire.

Thanks! snicker

--
Richard addressing Rot Speed:
"**** you're thick/pathetic excuse for a troll."
MID:

On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to
each house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

I'm talking about the older wiring where there are three separate wires,
rather than the upgraded wiring where there is a twisted bundle of three
wires (or four if there is also a neutral). Obviously in the latter case
the wires in the bundle will need to be insulated.

Ant chance of a photo?

--
Adam

"Peeler" wrote in message
news
On Mon, 9 Jul 2018 20:14:04 +1000, cantankerous geezer Rot Speed
blabbered,
again:

When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to
each
house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

With mine, the wires down the street on the poles arent insulated,
but the 4 wires from the pole to the mains fuses on the bargeboard
of my house are insulated and twisted together. I have a two phase
supply to the house because I have an off peak storage heater that
I no longer use, and they use a single 4 wire cable to the houses
when more than one phase is supplied to the house and just don¢t
use the spare 4th wire.

How common is it for storage heaters to be fed off a different phase to the
rest of the house? The only house I owned was new enough to have underground
electricity cabling to the estate. It only had one meter (albeit a
dual-tariff one) and one fuse box (and they *were* fuses, rather than MCBs
and an RCD).

"ARW" wrote in message
news
On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to each
house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

I'm talking about the older wiring where there are three separate wires,
rather than the upgraded wiring where there is a twisted bundle of three
wires (or four if there is also a neutral). Obviously in the latter case
the wires in the bundle will need to be insulated.

Ant chance of a photo?

https://s22.postimg.cc/rnnern93l/20180709_182615.jpg

Three phase wires running horizontally, with two wires from two of the three
phase wires going to our house. Ignore the phone wires lower down the pole.

On 09/07/2018 18:25, NY wrote:
"Peeler" wrote in message
news
On Mon, 9 Jul 2018 20:14:04 +1000, cantankerous geezer Rot Speed
blabbered,
again:

When houses have their 240V mains supply delivered by overhead wires
(eg
on wooden poles) in the street, rather than being fed underground to
each
house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

With mine, the wires down the street on the poles arent insulated,
but the 4 wires from the pole to the mains fuses on the bargeboard
of my house are insulated and twisted together. I have a two phase
supply to the house because I have an off peak storage heater that
I no longer use, and they use a single 4 wire cable to the houses
when more than one phase is supplied to the house and just don¢t
use the spare 4th wire.

How common is it for storage heaters to be fed off a different phase to
the rest of the house? The only house I owned was new enough to have
underground electricity cabling to the estate. It only had one meter
(albeit a dual-tariff one) and one fuse box (and they *were* fuses,
rather than MCBs and an RCD).

It's quite common for storage heaters to be fed off a different phase to
the rest of the house in overhead networks to balance the load on the
network evenly.

Usually the storage heater circuits would be on a separate fuse box
which would be fed from a timeswitch or contactor.

On 09/07/2018 18:34, NY wrote:
"ARW" wrote in message
news
On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires
(eg on wooden poles) in the street, rather than being fed underground
to each house, are the three phase wires (and the two wires to each
house) insulated, or are they simply prevented from shorting by the
spacing of them?

I'm talking about the older wiring where there are three separate
wires, rather than the upgraded wiring where there is a twisted
bundle of three wires (or four if there is also a neutral). Obviously
in the latter case the wires in the bundle will need to be insulated.

Ant chance of a photo?

https://s22.postimg.cc/rnnern93l/20180709_182615.jpg

Three phase wires running horizontally, with two wires from two of the
three phase wires going to our house. Ignore the phone wires lower down
the pole.

Did you mean to say three wires running *vertically*? That is what the
image shows.

The 2 wires to your house are likely to be phase and nuetral.

On 09/07/18 18:13, ARW wrote:
On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires
(eg on wooden poles) in the street, rather than being fed underground
to each house, are the three phase wires (and the two wires to each
house) insulated, or are they simply prevented from shorting by the
spacing of them?

I'm talking about the older wiring where there are three separate
wires, rather than the upgraded wiring where there is a twisted bundle
of three wires (or four if there is also a neutral). Obviously in the
latter case the wires in the bundle will need to be insulated.

Ant chance of a photo?

NO overhead rings are insulated.

And the wires to the house - the last two phasers - seldom are



--
Gun Control: The law that ensures that only criminals have guns.

On 09/07/2018 18:34, NY wrote:
"ARW" wrote in message
news
On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires
(eg on wooden poles) in the street, rather than being fed underground
to each house, are the three phase wires (and the two wires to each
house) insulated, or are they simply prevented from shorting by the
spacing of them?

I'm talking about the older wiring where there are three separate
wires, rather than the upgraded wiring where there is a twisted
bundle of three wires (or four if there is also a neutral). Obviously
in the latter case the wires in the bundle will need to be insulated.

Ant chance of a photo?

https://s22.postimg.cc/rnnern93l/20180709_182615.jpg

Three phase wires running horizontally, with two wires from two of the
three phase wires going to our house. Ignore the phone wires lower down
the pole.


And one where it meets your house please.


But I would say that they are uninsulated.


--
Adam

On 09/07/2018 18:34, NY wrote:
"ARW" wrote in message
news
On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires
(eg on wooden poles) in the street, rather than being fed underground
to each house, are the three phase wires (and the two wires to each
house) insulated, or are they simply prevented from shorting by the
spacing of them?

I'm talking about the older wiring where there are three separate
wires, rather than the upgraded wiring where there is a twisted
bundle of three wires (or four if there is also a neutral). Obviously
in the latter case the wires in the bundle will need to be insulated.

Ant chance of a photo?

https://s22.postimg.cc/rnnern93l/20180709_182615.jpg

Three phase wires running horizontally, with two wires from two of the
three phase wires going to our house. Ignore the phone wires lower down
the pole.

You would likely find that pole only has two phases and neutral rather
than three phase - they may choose not to run the third if its only a
"dead leg" run of poles to a relatively low estimated total load.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 09/07/2018 11:14, NY wrote:
"Huge" wrote in message
...
Our last house was supplied overhead through fields. 240V from a pole
pig several hundred yards away. Originally the wires were uninsulated
and about a foot apart.

I first suspected that they were uninsulated when a lad at school threw
a metal coathanger at the overhead wires that ran along the road outside
the school. There was a bright flash and the coathanger fell down with a
huge nick melted out of the metal. Up until then I'd always assumed that
"all" wires were insulated. It was the first time I'd seen overhead 240V
cables: all the houses I've lived in apart from the most recent had
underground mains.

I wonder how many people would work close to the point where the wires
attach to the insulators on the house (eg when painting the house) if
they knew that the wires were uninsulated and therefore liable to give
you a nasty shock if you touch the live one.

Our last house was one of several terraces each of three houses. All of
them were fed from a single feed from the road, with a single multi-core
cable stapled all along the back of the house and then a short length of
three separate (uninsulated?) wires over the driveway between one
terrace and the next. Since there were three wires from the road, I
presume different houses were fed from different phases, rather than all
of them from the same phase.

We had to have several poles replaced because
The most impressive thing was the UniMog 6x6 pole handling machine - one
guy just "drilled" a hole in the ground and pushed the pole into it. Took
about 2 minutes per pole. They just chainsawed the old ones off (and I
kept them - one subsequently made a very good gatepost). Despite being
over 40 years old, they still smelled of creosote when cut.

Back in the days when creosote was *real* creosote before the H&S brigade
"watered it down". I'm not sure what the modern replacement is for
creosote,
when treating wood to make it non-rotting.


I watched the electricity company replacing the wooden poles and 11 kV
to 240V pole-mounted transformer opposite our house. The old transformer
was mounted on a single pole, but they replaced it with a new, smaller
on, though mounted on two poles a foot apart. The power was only off for
about half an hour, so they worked quickly. I always wondered how often
they used those pole-mounted switches, operated with the sort of rod
that is used to open high windows in a school hall. I imagine that was a
prime example: to be able to isolate the 11 kV feed somewhere upstream
while they replaced the transformer.

Now I bet if you threw a coathanger at the 11 kV wires that cross the
field, you'd get more than a little flash. Mind you, I'm sure the wires
are spaced a bit more widely than the length of a coathanger.

You can sometimes see the green copper 'corrosion' on older wires that
are sheltered from rain.

On 09/07/2018 18:34, NY wrote:
"ARW" wrote in message
news
On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires
(eg on wooden poles) in the street, rather than being fed underground
to each house, are the three phase wires (and the two wires to each
house) insulated, or are they simply prevented from shorting by the
spacing of them?

I'm talking about the older wiring where there are three separate
wires, rather than the upgraded wiring where there is a twisted
bundle of three wires (or four if there is also a neutral). Obviously
in the latter case the wires in the bundle will need to be insulated.

Ant chance of a photo?

https://s22.postimg.cc/rnnern93l/20180709_182615.jpg

Three phase wires running horizontally, with two wires from two of the
three phase wires going to our house. Ignore the phone wires lower down
the pole.

That's an old pole because it still has a BT phone wire sharing the
pole, something they avoid with upgraded installations.

On 09/07/2018 19:16, Tufnell Park wrote:
It's quite common for storage heaters to be fed off a different phase to
the rest of the house in overhead networks to balance the load on the
network evenly.

that would be difficult with just a live and neutral supply, especially
in rural area weere it is common to see just a pair of HV lines feeding
a rural transformer that then supplies live and neutral to a small
hamlet of houses.

The three phases are normally used to feed each third house
so that is how they are balanced. If each of the three
houses had storage heaters (as many houses did in the 50's
and 60's) how on earth would they manage with only three
phases ?.

Saw this last month.
https://www.dropbox.com/s/u4a7bhfas7...c%201.jpg?dl=0
https://www.dropbox.com/s/odxzvdnr68...c%202.jpg?dl=0

Bill

NY wrote
Rod Speed wrote
NY wrote

When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to
each house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

With mine, the wires down the street on the poles arent insulated,
but the 4 wires from the pole to the mains fuses on the bargeboard
of my house are insulated and twisted together. I have a two phase
supply to the house because I have an off peak storage heater that
I no longer use, and they use a single 4 wire cable to the houses
when more than one phase is supplied to the house and just don¢t
use the spare 4th wire.

How common is it for storage heaters to be fed off a different phase to
the rest of the house?

They weren't with mine. The whole house is on two phases
with both lights and GPOs and the big stuff like ovens and
cook tops distributed over the two phases too.

Don't forget that this is australia, not britain.

The only house I owned was new enough to have underground electricity
cabling to the estate. It only had one meter (albeit a dual-tariff one)
and one fuse box (and they *were* fuses, rather than MCBs and an RCD).

On 09/07/2018 20:53, Andrew wrote:
On 09/07/2018 19:16, Tufnell Park wrote:
It's quite common for storage heaters to be fed off a different phase
to the rest of the house in overhead networks to balance the load on
the network evenly.

that would be difficult with just a live and neutral supply, especially
in rural area weere it is common to see just a pair of HV lines feeding
a rural transformer that then supplies live and neutral to a small
hamlet of houses.

The three phases are normally used to feed each third house
so that is how they are balanced. If each of the three
houses had storage heaters (as many houses did in the 50's
and 60's) how on earth would they manage with only three
phases ?.

It could still be balanced but would just require a larger supply
tramsformer.

Saw this last month.
https://www.dropbox.com/s/u4a7bhfas7...c%201.jpg?dl=0
https://www.dropbox.com/s/odxzvdnr68...c%202.jpg?dl=0

Bill

I bet that wiped out TMS.

--

Graham.
%Profound_observation%

On 09/07/2018 11:14, NY wrote:
"Huge" wrote in message
...
Our last house was supplied overhead through fields. 240V from a pole
pig several hundred yards away. Originally the wires were uninsulated
and about a foot apart.

I first suspected that they were uninsulated when a lad at school threw
a metal coathanger at the overhead wires that ran along the road outside
the school. There was a bright flash and the coathanger fell down with a
huge nick melted out of the metal. Up until then I'd always assumed that
"all" wires were insulated. It was the first time I'd seen overhead 240V
cables: all the houses I've lived in apart from the most recent had
underground mains.

I wonder how many people would work close to the point where the wires
attach to the insulators on the house (eg when painting the house) if
they knew that the wires were uninsulated and therefore liable to give
you a nasty shock if you touch the live one.

Our last house was one of several terraces each of three houses. All of
them were fed from a single feed from the road, with a single multi-core
cable stapled all along the back of the house and then a short length of
three separate (uninsulated?) wires over the driveway between one
terrace and the next. Since there were three wires from the road, I
presume different houses were fed from different phases, rather than all
of them from the same phase.

We had to have several poles replaced because
The most impressive thing was the UniMog 6x6 pole handling machine - one
guy just "drilled" a hole in the ground and pushed the pole into it. Took
about 2 minutes per pole. They just chainsawed the old ones off (and I
kept them - one subsequently made a very good gatepost). Despite being
over 40 years old, they still smelled of creosote when cut.

Back in the days when creosote was *real* creosote before the H&S brigade
"watered it down". I'm not sure what the modern replacement is for
creosote,
when treating wood to make it non-rotting.

Creosote is still the preferred option for telegraph and power poles AFAIK.

SteveW

NY wrote
Rod Speed wrote
NY wrote

When houses have their 240V mains supply delivered by overhead wires (eg
on wooden poles) in the street, rather than being fed underground to
each house, are the three phase wires (and the two wires to each house)
insulated, or are they simply prevented from shorting by the spacing of
them?

With mine, the wires down the street on the poles arent insulated,
but the 4 wires from the pole to the mains fuses on the bargeboard
of my house are insulated and twisted together. I have a two phase
supply to the house because I have an off peak storage heater that
I no longer use, and they use a single 4 wire cable to the houses
when more than one phase is supplied to the house and just don¢t
use the spare 4th wire.

How common is it for storage heaters to be fed off a different phase to
the rest of the house?

They weren't with mine. The whole house is on two phases
with both lights and GPOs and the big stuff like ovens and
cook tops distributed over the two phases too.

Don't forget that this is australia, not britain.

I don't think it is 2 phase although it may be called that
colloqually.
Isn't it single phase 3 wire AKA split phase ie your local transformer
has a centre tap neutral.

Do you get to use the full 460v in your house?

--

Graham.
%Profound_observation%

On Tue, 10 Jul 2018 07:31:27 +1000, cantankerous geezer Rot Speed blabbered,
again:

They weren't with mine. The whole house is on two phases
with both lights and GPOs and the big stuff like ovens and
cook tops distributed over the two phases too.

Don't forget that this is australia, not britain.

Don't forget, oh senile one: this is a UK ng, NOT an Ozzie ng! tsk

--
Cursitor Doom about Rot Speed:
"The man is a conspicuous and unashamed ignoramus."
MID:

"Graham." wrote in message
...
NY wrote
Rod Speed wrote
NY wrote

When houses have their 240V mains supply delivered by overhead wires
(eg
on wooden poles) in the street, rather than being fed underground to
each house, are the three phase wires (and the two wires to each
house)
insulated, or are they simply prevented from shorting by the spacing
of
them?

With mine, the wires down the street on the poles arent insulated,
but the 4 wires from the pole to the mains fuses on the bargeboard
of my house are insulated and twisted together. I have a two phase
supply to the house because I have an off peak storage heater that
I no longer use, and they use a single 4 wire cable to the houses
when more than one phase is supplied to the house and just don¢t
use the spare 4th wire.

How common is it for storage heaters to be fed off a different phase to
the rest of the house?

They weren't with mine. The whole house is on two phases
with both lights and GPOs and the big stuff like ovens and
cook tops distributed over the two phases too.

Don't forget that this is australia, not britain.

I don't think it is 2 phase although it may be called that colloqually.

It is in fact 2 phase. There are 3 phases down the street on 4 wires,
one extra for the neutral. Most houses get just one phase, those
that can show that they need it get a 3 phase supply and those that
have off peak storage heaters get a 2 phase supply and the heater
gets both phases because the power loading is too high for one.

Isn't it single phase 3 wire AKA split phase ie
your local transformer has a centre tap neutral.

Nope, the 11KV supply on the top of the poles is 3 wires.

Do you get to use the full 460v in your house?

That isnt what you get with a 2 phase supply.

On Tue, 10 Jul 2018 08:44:49 +1000, cantankerous geezer Rot Speed blabbered,
again:


I don't think it is 2 phase although it may be called that colloqually.

It is in fact 2 phase. There are 3 phases down the street on 4 wires,
one extra for the neutral. Most houses get

Darn, did you find some rare simpleton who took your latest troll again,
Rot?

--
Richard addressing Rot Speed:
"**** you're thick/pathetic excuse for a troll."
MID:

On 09/07/18 20:44, John Rumm wrote:
On 09/07/2018 18:34, NY wrote:
"ARW" wrote in message
news
On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires
(eg on wooden poles) in the street, rather than being fed
underground to each house, are the three phase wires (and the two
wires to each house) insulated, or are they simply prevented from
shorting by the spacing of them?

I'm talking about the older wiring where there are three separate
wires, rather than the upgraded wiring where there is a twisted
bundle of three wires (or four if there is also a neutral).
Obviously in the latter case the wires in the bundle will need to be
insulated.

Ant chance of a photo?

https://s22.postimg.cc/rnnern93l/20180709_182615.jpg

Three phase wires running horizontally, with two wires from two of the
three phase wires going to our house. Ignore the phone wires lower
down the pole.

You would likely find that pole only has two phases and neutral rather
than three phase - they may choose not to run the third if its only a
"dead leg" run of poles to a relatively low estimated total load.

Neutral does not really exist for three phases. I have never seen a two
phase plus neutral overhead feed and can't see any technical reason for it

Out here its all three phase 11 KV overhead stepping down to three phase
240v stuff with the neutral 'reconstituted' at the transformer

Or occasionally a two wire only feed to a single remote property that is
just two phases and no neutral.




--
"A point of view can be a dangerous luxury when substituted for insight
and understanding".

Marshall McLuhan

On 09/07/2018 20:48, Andrew wrote:
On 09/07/2018 18:34, NY wrote:
"ARW" wrote in message
news
On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires
(eg on wooden poles) in the street, rather than being fed
underground to each house, are the three phase wires (and the two
wires to each house) insulated, or are they simply prevented from
shorting by the spacing of them?

I'm talking about the older wiring where there are three separate
wires, rather than the upgraded wiring where there is a twisted
bundle of three wires (or four if there is also a neutral).
Obviously in the latter case the wires in the bundle will need to be
insulated.

Ant chance of a photo?

https://s22.postimg.cc/rnnern93l/20180709_182615.jpg

Three phase wires running horizontally, with two wires from two of the
three phase wires going to our house. Ignore the phone wires lower
down the pole.

Vertically. Horizontal is typically uninsulated 11kV or higher. Vertical
is domestic supply. Since there are no strips of insulation hanging off
or visible changes in wire diameter I'd say they were completely
uninsulated now even if in the dim and distant past they once had some.

That's an old pole because it still has a BT phone wire sharing the
pole, something they avoid with upgraded installations.

They are still very common in rural areas like mine. BT cables still
share the somewhat bent mains electricity poles even today.

The mains has been upgraded to a modern aluminium full insulated 3 phase
bundle but the cables all share the same poles. Which means we lose both
landline phone and electricity simultaneously when the milk tanker fails
to make it round the corner on a frosty morning.

--
Regards,
Martin Brown

On 09/07/2018 19:16, Tufnell Park wrote:
On 09/07/2018 18:25, NY wrote:

How common is it for storage heaters to be fed off a different phase
to the rest of the house? The only house I owned was new enough to
have underground electricity cabling to the estate. It only had one
meter (albeit a dual-tariff one) and one fuse box (and they *were*
fuses, rather than MCBs and an RCD).

It's quite common for storage heaters to be fed off a different phase to
the rest of the house in overhead networks to balance the load on the
network evenly.

Only on new build or a very large house which already had more than one
phase supply because they exceeded the standard single phase capacity.
(our VH is wired that way to keep the phases in balance)

Usually the storage heater circuits would be on a separate fuse box
which would be fed from a timeswitch or contactor.

The storage heaters from the electricity too cheap to meter era were
just retrofitted onto the existing single phase mains feed through an
economy-7 tariff meter and relied on the house base load being low at night.

I doubt if the 60A ? feed into my parents home could have handled the
electric fires, oven and storage heaters all on at once. My recollection
is that they were utterly useless big ugly things making the house way
too hot overnight and were freezing cold by the time you got home in the
evening. They were better designed into in purpose built modern build.

Modern insulation and draft proofing may tip the balance in their favour
but I remain unconvinced of their merits. Resistive electric heating is
about the most expensive possible form of space heating that there is.

Only burning £20 notes to keep warm would be worse.

--
Regards,
Martin Brown

"The Natural Philosopher" wrote in message
news
On 09/07/18 20:44, John Rumm wrote:
On 09/07/2018 18:34, NY wrote:
"ARW" wrote in message
news On 09/07/2018 09:20, NY wrote:
When houses have their 240V mains supply delivered by overhead wires
(eg on wooden poles) in the street, rather than being fed underground
to each house, are the three phase wires (and the two wires to each
house) insulated, or are they simply prevented from shorting by the
spacing of them?

I'm talking about the older wiring where there are three separate
wires, rather than the upgraded wiring where there is a twisted bundle
of three wires (or four if there is also a neutral). Obviously in the
latter case the wires in the bundle will need to be insulated.

Ant chance of a photo?

https://s22.postimg.cc/rnnern93l/20180709_182615.jpg

Three phase wires running horizontally, with two wires from two of the
three phase wires going to our house. Ignore the phone wires lower down
the pole.

You would likely find that pole only has two phases and neutral rather
than three phase - they may choose not to run the third if its only a
"dead leg" run of poles to a relatively low estimated total load.

Neutral does not really exist for three phases.

It does here. The street cables down the street are 4 wires with the 240/415
supply.

I have never seen a two phase plus neutral overhead feed

Then you need to get out more.

and can't see any technical reason for it

Because most of the houses have a single active and neutral feed.

Out here its all three phase 11 KV overhead stepping down to three phase
240v stuff with the neutral 'reconstituted' at the transformer

Still a neutral.

Or occasionally a two wire only feed to a single remote property that is
just two phases and no neutral.

Doesnt happen here.