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Default *Five* wire overhead mains cables

Roger Hayter wrote:

You could try wiring this extension with proper twisted pair instead of
ordinary telephone internal wiring which isn't (twisted, that is).


It seems impossible to find an official GPO/BT/Openreach spec for CW1308
internal phone cable, but various manufacturers specify theat they use
different lay-lengths for the individual twisted pairs, e.g.

http://www.caledonian-cables.co.uk/Telephone/Indoor/CW1308.htm
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On 17/04/2021 10:03, ARW wrote:
On 17/04/2021 09:43, charles wrote:
In article ,
*** ARW wrote:
On 17/04/2021 08:15, Andy Burns wrote:
ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77

WTF?

insulating spacers to stop the phases getting too close in the wind?


Yep. I see it when I look further down.


And a customer sent me this last week


https://www.youtube.com/watch?v=uUow...tishPath%C3%A9


before the days of H&S. No hard hats, no harnesses, even the club hammer
had to safety chain* ----- mmmm


This one has a bloke in a suit going up the pylon

https://www.youtube.com/watch?v=MGiT...tishPath%C3%A9


The man's got no bloody tie on! Shoddy dress leads to shoddy work.


--
Robin
(approved by HRH Prince Philip & sent in his absence)
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On 16/04/2021 22:26, Rod Speed wrote:
"Scott" wrote in message
...
On Fri, 16 Apr 2021 20:36:02 +0100, charles
wrote:
In article , NY wrote:


What are the circumstances when overhead mains wiring has an extra
earth
wire, rather than the earthing being done at each house? I've never
seen
it before. Come to think of it, why do some installations have a
neutral
wire and some don't - are there cases where the nett load is
expected to
be unbalanced on the three phases, requiring an extra neutral?

Are you saying that telephone wires in the UK always require separate
poles and can't be carried on electricity poles?

that certainly used to be the safety requirement.* Nobody wanted 240v on
their telephone.


I would have thought 240V at the exchange would be an even bigger
problem.


Nope, they have to have some protection against lightning strikes
and that works for 240 volts too. In fact many street power lines
have 11KV lines at the top of the poles too and sometimes someone
drives into a pole and brings it down, with the 11KV lines with it.


Is that 11kV between phases?

--
Max Demian
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On 17/04/2021 09:11, Andy Burns wrote:
ARW wrote:

Andy Burns wrote:

ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77
WTF?

insulating spacers to stop the phases getting too close in the wind?


Yep. I see it when I look further down.
And a customer sent me this last week
https://www.youtube.com/watch?v=uUow...tishPath%C3%A9


But those "X" spacers which the commentator says are to stop them
shorting the system, are on wires of the same phase!

they are to stop wires *chafing*,when on the same phase.


--
Socialism is the philosophy of failure, the creed of ignorance and the
gospel of envy.

Its inherent virtue is the equal sharing of misery.

Winston Churchill

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On 17/04/2021 10:06, Peter Able wrote:
If all of your extensions are simply connected across the incoming pair,
then induced hum won't just affect one extension.


I thought about that, and then decided as a statement of fact it was
********.

Consider a set of telephone wires all starred from a single point where
they are all shorted together. Telephones are oin te end of each pair.

One of the wires goes through a transformer that is designed to induce
current in it. The telephone on that wire and that wire alone will see
'hum'.



--
It is dangerous to be right in matters on which the established
authorities are wrong.

Voltaire, The Age of Louis XIV


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"ARW" wrote in message
...
On 17/04/2021 09:43, charles wrote:
In article ,
ARW wrote:
On 17/04/2021 08:15, Andy Burns wrote:
ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77

WTF?

insulating spacers to stop the phases getting too close in the wind?


Yep. I see it when I look further down.


And a customer sent me this last week


https://www.youtube.com/watch?v=uUow...tishPath%C3%A9


before the days of H&S. No hard hats, no harnesses, even the club hammer
had to safety chain ----- mmmm


This one has a bloke in a suit going up the pylon


**** you lot are weird. No tie either.

https://www.youtube.com/watch?v=MGiT...tishPath%C3%A9



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In article ,
Scott wrote:
Are you saying that telephone wires in the UK always require separate poles
and can't be carried on electricity poles?


I thought they picked up hum if they ran parallel to an electricity
cable.


Telephone pairs are balanced and should be relatively immune to picking up
hum.

Unlike the bodge that was the BT three wire house wiring. That is
excellent at picking up induced signals.

--
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Dave Plowman London SW
To e-mail, change noise into sound.
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On Sat, 17 Apr 2021 11:15:53 +0100, The Natural Philosopher
wrote:

On 17/04/2021 10:06, Peter Able wrote:
If all of your extensions are simply connected across the incoming pair,
then induced hum won't just affect one extension.


I thought about that, and then decided as a statement of fact it was
********.

Consider a set of telephone wires all starred from a single point where
they are all shorted together. Telephones are oin te end of each pair.

One of the wires goes through a transformer that is designed to induce
current in it. The telephone on that wire and that wire alone will see
'hum'.


Except that mine are wired as a spur. I am quite surprised the hum
does not go back the way to number 2.
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On 17/04/2021 08:37, The Natural Philosopher wrote:
On 16/04/2021 18:46, NY wrote:


Are you saying that telephone wires in the UK always require separate
poles and can't be carried on electricity poles?


yes.


Only for new installations

Climbing a power pole requires a hugely different safety regime from
skinning up a telephone pole.


Historically, when the suppliers were all nationalised there were
occasions where telephone cables were added onto electric poles,
usually done in the era when a lot fewer people had phones so
installing new poles just for one new subscriber wouldn't be
cost effective.


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On 17/04/2021 10:50, Robin wrote:
On 17/04/2021 10:03, ARW wrote:
On 17/04/2021 09:43, charles wrote:
In article ,
*** ARW wrote:
On 17/04/2021 08:15, Andy Burns wrote:
ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77

WTF?

insulating spacers to stop the phases getting too close in the wind?


Yep. I see it when I look further down.

And a customer sent me this last week

https://www.youtube.com/watch?v=uUow...tishPath%C3%A9


before the days of H&S. No hard hats, no harnesses, even the club hammer
had to safety chain* ----- mmmm


This one has a bloke in a suit going up the pylon

https://www.youtube.com/watch?v=MGiT...tishPath%C3%A9


The man's got no bloody tie on! Shoddy dress leads to shoddy work.


And not smoking.


--
Adam


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On 17/04/2021 10:50, Robin wrote:
On 17/04/2021 10:03, ARW wrote:
On 17/04/2021 09:43, charles wrote:
In article ,
*** ARW wrote:
On 17/04/2021 08:15, Andy Burns wrote:
ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77

WTF?

insulating spacers to stop the phases getting too close in the wind?


Yep. I see it when I look further down.

And a customer sent me this last week

https://www.youtube.com/watch?v=uUow...tishPath%C3%A9


before the days of H&S. No hard hats, no harnesses, even the club hammer
had to safety chain* ----- mmmm


This one has a bloke in a suit going up the pylon

https://www.youtube.com/watch?v=MGiT...tishPath%C3%A9


The man's got no bloody tie on! Shoddy dress leads to shoddy work.


That's early H&S - you wouldn't want him to risk catching the tie and
hanging himself!

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On Sat, 17 Apr 2021 20:33:04 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH the trolling senile asshole's latest troll**** unread
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Andy Burns wrote:
NY wrote:

I'm used to seeing three-wire (three phases) overhead mains wiring from
poles along a street.
But I'm mystified about five-wire mains.


TN-S system (not TN-C-S)

L1, L2, L3, N, PE


What happens with TN-S if you are fed from a pole? Do you get a separate
earth conductor, or are they all TN-C-S or TT?

One possibility in the OP's setup is it's TN-S because it goes to a buried
cable somewhere, and the earth is to earth the cable sheath.

Theo
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"Max Demian" wrote in message
o.uk...
On 16/04/2021 22:26, Rod Speed wrote:
"Scott" wrote in message
...
On Fri, 16 Apr 2021 20:36:02 +0100, charles
wrote:
In article , NY wrote:


What are the circumstances when overhead mains wiring has an extra
earth
wire, rather than the earthing being done at each house? I've never
seen
it before. Come to think of it, why do some installations have a
neutral
wire and some don't - are there cases where the nett load is expected
to
be unbalanced on the three phases, requiring an extra neutral?

Are you saying that telephone wires in the UK always require separate
poles and can't be carried on electricity poles?

that certainly used to be the safety requirement. Nobody wanted 240v
on
their telephone.

I would have thought 240V at the exchange would be an even bigger
problem.


Nope, they have to have some protection against lightning strikes
and that works for 240 volts too. In fact many street power lines
have 11KV lines at the top of the poles too and sometimes someone
drives into a pole and brings it down, with the 11KV lines with it.


Is that 11kV between phases?


Nope, from ground.

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On Sun, 18 Apr 2021 06:21:59 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH the trolling senile asshole's troll****

--
Keema Nam addressing nym-shifting senile Rodent:
"You are now exposed as a liar, as well as an ignorant troll."
"MID: .com"


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Andrew wrote:
On 17/04/2021 08:37, The Natural Philosopher wrote:
On 16/04/2021 18:46, NY wrote:


Are you saying that telephone wires in the UK always require separate
poles and can't be carried on electricity poles?


yes.


Only for new installations

Climbing a power pole requires a hugely different safety regime from
skinning up a telephone pole.


Historically, when the suppliers were all nationalised there were
occasions where telephone cables were added onto electric poles,
usually done in the era when a lot fewer people had phones so
installing new poles just for one new subscriber wouldn't be
cost effective.




The introduction of fibre has caused some scenarios where the present
distribution companies
have created a fuss because they say it is new technology not covered by
the long standing agreements that allowed the Post Office and its
successors to affix a copper phone line on suitable power poles so
Openreach if it wants to run a fibre has to make its own arrangements.

GH


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On 17/04/2021 12:01, Scott wrote:
On Sat, 17 Apr 2021 11:15:53 +0100, The Natural Philosopher
wrote:

On 17/04/2021 10:06, Peter Able wrote:
If all of your extensions are simply connected across the incoming pair,
then induced hum won't just affect one extension.


I thought about that, and then decided as a statement of fact it was
********.

Consider a set of telephone wires all starred from a single point where
they are all shorted together. Telephones are oin te end of each pair.

One of the wires goes through a transformer that is designed to induce
current in it. The telephone on that wire and that wire alone will see
'hum'.


Except that mine are wired as a spur. I am quite surprised the hum
does not go back the way to number 2.


Philosopher, starting with a false assumption is always a bad start, but
star, daisy-chain or hybrid. Would you describe the path(s) of the
induced currents for no handsets lifted and for each handset in turn lifted?

Scott, have you tried swapping around the handsets? Just a bit more
evidence.

PA

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On 17/04/2021 12:36, Andrew wrote:
On 17/04/2021 08:37, The Natural Philosopher wrote:
On 16/04/2021 18:46, NY wrote:


Are you saying that telephone wires in the UK always require
separate poles and can't be carried on electricity poles?


yes.


Only for new installations

Climbing a power pole requires a hugely different safety regime from
skinning up a telephone pole.


Historically, when the suppliers were all nationalised there were
occasions where telephone cables were added onto electric poles,
usually done in the era when a lot fewer people had phones so
installing new poles just for one new subscriber wouldn't be
cost effective.


There are loads of telephone cables sharing electricity poles near me



Our own telephone cable also comes via an electricity pole too, though
it starts life on a BT pole the other side of the road.

If/when that gets replaced by FTTP, are you saying it'll have to run
either directly from BT's own pole (and not involve the electricity pole)?


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On Mon, 19 Apr 2021 13:45:37 +0100, Mark Carver wrote:

If/when that gets replaced by FTTP, are you saying it'll have to run
either directly from BT's own pole (and not involve the electricity
pole)?


Not the case here when FTTP was put in. They used the same poles for the
fibre as did the copper and the electricity. Pole sharing is not
unusual, certainly in rural areas.
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In article ,
Mark Carver wrote:
On 17/04/2021 12:36, Andrew wrote:
On 17/04/2021 08:37, The Natural Philosopher wrote:
On 16/04/2021 18:46, NY wrote:


Are you saying that telephone wires in the UK always require
separate poles and can't be carried on electricity poles?

yes.


Only for new installations

Climbing a power pole requires a hugely different safety regime from
skinning up a telephone pole.


Historically, when the suppliers were all nationalised there were
occasions where telephone cables were added onto electric poles,
usually done in the era when a lot fewer people had phones so
installing new poles just for one new subscriber wouldn't be
cost effective.


There are loads of telephone cables sharing electricity poles near me




Our own telephone cable also comes via an electricity pole too, though
it starts life on a BT pole the other side of the road.


If/when that gets replaced by FTTP, are you saying it'll have to run
either directly from BT's own pole (and not involve the electricity pole)?



Less needed with fibre. It's not a good conductor of eletricity

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle


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On 19/04/2021 14:32, charles wrote:
If/when that gets replaced by FTTP, are you saying it'll have to run
either directly from BT's own pole (and not involve the electricity pole)?


Less needed with fibre. It's not a good conductor of eletricity

Indeed it's not, but I think the concern here is BT Openreach personnel
are !
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On 17/04/2021 11:11, The Natural Philosopher wrote:
On 17/04/2021 09:11, Andy Burns wrote:
ARW wrote:

Andy Burns wrote:

ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77
WTF?

insulating spacers to stop the phases getting too close in the wind?

Yep. I see it when I look further down.
And a customer sent me this last week
https://www.youtube.com/watch?v=uUow...tishPath%C3%A9


But those "X" spacers which the commentator says are to stop them
shorting the system, are on wires of the same phase!

they are to stop wires *chafing*,when on the same phase.


No, the X spacers for the four conductors on each phase of supergrid
lines give the overall conductor an electric field distribution more
like a larger diameter conductor, reducing the corona losses. I guess
they also reduce the conductor temperature at a given current from the
level if all the aluminium conductor was wrapped around a single steel
(load carrying) core.
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On 17/04/2021 09:11, Andy Burns wrote:
ARW wrote:

Andy Burns wrote:

ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77
WTF?

insulating spacers to stop the phases getting too close in the wind?


Yep. I see it when I look further down.
And a customer sent me this last week
https://www.youtube.com/watch?v=uUow...tishPath%C3%A9


But those "X" spacers which the commentator says are to stop them
shorting the system, are on wires of the same phase!

See my resp to TNP below
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On 19 Apr 2021 at 13:45:37 BST, "Mark Carver"
wrote:

On 17/04/2021 12:36, Andrew wrote:
On 17/04/2021 08:37, The Natural Philosopher wrote:
On 16/04/2021 18:46, NY wrote:


Are you saying that telephone wires in the UK always require
separate poles and can't be carried on electricity poles?

yes.


Only for new installations

Climbing a power pole requires a hugely different safety regime from
skinning up a telephone pole.


Historically, when the suppliers were all nationalised there were
occasions where telephone cables were added onto electric poles,
usually done in the era when a lot fewer people had phones so
installing new poles just for one new subscriber wouldn't be
cost effective.


There are loads of telephone cables sharing electricity poles near me




Our own telephone cable also comes via an electricity pole too, though
it starts life on a BT pole the other side of the road.

If/when that gets replaced by FTTP, are you saying it'll have to run
either directly from BT's own pole (and not involve the electricity pole)?


As a data point, our FTTP cable was run from the same pole outside our house
that carries our electricity supply and old copper telephone drop wire. And
those of several neighbours. So perhaps the rules about fibre cables only
applies to long runs rather than final connections, if it applies to all
electricity distributors.


--
Roger Hayter


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On 19 Apr 2021 at 14:51:32 BST, "Mark Carver"
wrote:

On 19/04/2021 14:32, charles wrote:
If/when that gets replaced by FTTP, are you saying it'll have to run
either directly from BT's own pole (and not involve the electricity pole)?


Less needed with fibre. It's not a good conductor of eletricity

Indeed it's not, but I think the concern here is BT Openreach personnel
are !


And don't the fibre cables include a steel rope to take the tension?

--
Roger Hayter




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On 19/04/2021 14:32, charles wrote:


Less needed with fibre. It's not a good conductor of eletricity


Is there a steel catenary wire inside that hollow tubing used
to support overhead fibre ?.
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On 19/04/2021 13:45, Mark Carver wrote:
On 17/04/2021 12:36, Andrew wrote:
On 17/04/2021 08:37, The Natural Philosopher wrote:
On 16/04/2021 18:46, NY wrote:


Are you saying that telephone wires in the UK always require
separate poles and can't be carried on electricity poles?

yes.


Only for new installations

Climbing a power pole requires a hugely different safety regime from
skinning up a telephone pole.


Historically, when the suppliers were all nationalised there were
occasions where telephone cables were added onto electric poles,
usually done in the era when a lot fewer people had phones so
installing new poles just for one new subscriber wouldn't be
cost effective.


There are loads of telephone cables sharing electricity poles near me



what a bodge

Our own telephone cable also comes via an electricity pole too, though
it starts life on a BT pole the other side of the road.

If/when that gets replaced by FTTP, are you saying it'll have to run
either directly from BT's own pole (and not involve the electricity pole)?


If its 'always been done that way' my guess is it will still be done
that way!


--
it should be clear by now to everyone that activist environmentalism
(or environmental activism) is becoming a general ideology about humans,
about their freedom, about the relationship between the individual and
the state, and about the manipulation of people under the guise of a
'noble' idea. It is not an honest pursuit of 'sustainable development,'
a matter of elementary environmental protection, or a search for
rational mechanisms designed to achieve a healthy environment. Yet
things do occur that make you shake your head and remind yourself that
you live neither in Joseph Stalins Communist era, nor in the Orwellian
utopia of 1984.

Vaclav Klaus
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On 20/04/2021 12:09, Roger Hayter wrote:
On 19 Apr 2021 at 14:51:32 BST, "Mark Carver"
wrote:

On 19/04/2021 14:32, charles wrote:
If/when that gets replaced by FTTP, are you saying it'll have to run
either directly from BT's own pole (and not involve the electricity pole)?

Less needed with fibre. It's not a good conductor of eletricity

Indeed it's not, but I think the concern here is BT Openreach personnel
are !


And don't the fibre cables include a steel rope to take the tension?

yes. and a copper pair, too.

--
it should be clear by now to everyone that activist environmentalism
(or environmental activism) is becoming a general ideology about humans,
about their freedom, about the relationship between the individual and
the state, and about the manipulation of people under the guise of a
'noble' idea. It is not an honest pursuit of 'sustainable development,'
a matter of elementary environmental protection, or a search for
rational mechanisms designed to achieve a healthy environment. Yet
things do occur that make you shake your head and remind yourself that
you live neither in Joseph Stalins Communist era, nor in the Orwellian
utopia of 1984.

Vaclav Klaus
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On 19/04/2021 16:09, newshound wrote:
On 17/04/2021 11:11, The Natural Philosopher wrote:
On 17/04/2021 09:11, Andy Burns wrote:
ARW wrote:

Andy Burns wrote:

ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77
WTF?

insulating spacers to stop the phases getting too close in the wind?

Yep. I see it when I look further down.
And a customer sent me this last week
https://www.youtube.com/watch?v=uUow...tishPath%C3%A9


But those "X" spacers which the commentator says are to stop them
shorting the system, are on wires of the same phase!

they are to stop wires *chafing*,when on the same phase.


No, the X spacers for the four conductors on each phase of supergrid
lines give the overall conductor an electric field distribution more
like a larger diameter conductor, reducing the corona losses.


No, that's what 4 wires instead of 1 does... the spacers are to *keep*
them 4 wires...:-) imagine 4 wires that close in a gust of wind...


I guess
they also reduce the conductor temperature at a given current from the
level if all the aluminium conductor was wrapped around a single steel
(load carrying) core.


Mmm. greater surface to volume? nah. I think that works the other way
cross section goes up as radius squared but area only goes up as radius.

Have I got that right - the cross section of 4 wires is the same as a
single wire twice the diameter so surface area of single wire is 2 pi D
whereas its 4 x pi x D for 4 wires...-oh ok, you are right. All other
things being equal that should run cooler - although from memory they
don't mind them getting hot, its the resistance they don't like.

Also factor in the mundane. Nice to stock just one kind of overhead
cable and get 4 x current carrying capacity with a few spacers and
different insulators.


--
it should be clear by now to everyone that activist environmentalism
(or environmental activism) is becoming a general ideology about humans,
about their freedom, about the relationship between the individual and
the state, and about the manipulation of people under the guise of a
'noble' idea. It is not an honest pursuit of 'sustainable development,'
a matter of elementary environmental protection, or a search for
rational mechanisms designed to achieve a healthy environment. Yet
things do occur that make you shake your head and remind yourself that
you live neither in Joseph Stalins Communist era, nor in the Orwellian
utopia of 1984.

Vaclav Klaus
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On 19/04/2021 16:10, newshound wrote:
On 17/04/2021 09:11, Andy Burns wrote:
ARW wrote:

Andy Burns wrote:

ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77
WTF?

insulating spacers to stop the phases getting too close in the wind?

Yep. I see it when I look further down.
And a customer sent me this last week
https://www.youtube.com/watch?v=uUow...tishPath%C3%A9


But those "X" spacers which the commentator says are to stop them
shorting the system, are on wires of the same phase!

See my resp to TNP below

And my reply.
They are there to make 4 wires stay as 4 wires.

--
When plunder becomes a way of life for a group of men in a society, over
the course of time they create for themselves a legal system that
authorizes it and a moral code that glorifies it.

Frédéric Bastiat


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Default *Five* wire overhead mains cables

On 20/04/2021 13:32, Andrew wrote:
On 19/04/2021 14:32, charles wrote:


Less needed with fibre. It's not a good conductor of eletricity


Is there a steel catenary wire inside that hollow tubing used
to support overhead fibre ?.


If so, then using kevlar would ensure that there was nothing conductive.
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On Sun, 18 Apr 2021 09:03:28 +0100, Peter Able wrote:

On 17/04/2021 12:01, Scott wrote:
On Sat, 17 Apr 2021 11:15:53 +0100, The Natural Philosopher
wrote:

On 17/04/2021 10:06, Peter Able wrote:
If all of your extensions are simply connected across the incoming pair,
then induced hum won't just affect one extension.

I thought about that, and then decided as a statement of fact it was
********.

Consider a set of telephone wires all starred from a single point where
they are all shorted together. Telephones are oin te end of each pair.

One of the wires goes through a transformer that is designed to induce
current in it. The telephone on that wire and that wire alone will see
'hum'.


Except that mine are wired as a spur. I am quite surprised the hum
does not go back the way to number 2.


Philosopher, starting with a false assumption is always a bad start, but
star, daisy-chain or hybrid. Would you describe the path(s) of the
induced currents for no handsets lifted and for each handset in turn lifted?

Scott, have you tried swapping around the handsets? Just a bit more
evidence.

No, but I thought of that as I was watching Netflix. I also found out
if I hold the line the buzzing increases !!! Maybe I am acting as an
aerial.
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Default *Five* wire overhead mains cables

On 20/04/2021 16:26, Scott wrote:
On Sun, 18 Apr 2021 09:03:28 +0100, Peter Able wrote:

On 17/04/2021 12:01, Scott wrote:
On Sat, 17 Apr 2021 11:15:53 +0100, The Natural Philosopher
wrote:

On 17/04/2021 10:06, Peter Able wrote:
If all of your extensions are simply connected across the incoming pair,
then induced hum won't just affect one extension.

I thought about that, and then decided as a statement of fact it was
********.

Consider a set of telephone wires all starred from a single point where
they are all shorted together. Telephones are oin te end of each pair.

One of the wires goes through a transformer that is designed to induce
current in it. The telephone on that wire and that wire alone will see
'hum'.

Except that mine are wired as a spur. I am quite surprised the hum
does not go back the way to number 2.


Philosopher, starting with a false assumption is always a bad start, but
star, daisy-chain or hybrid. Would you describe the path(s) of the
induced currents for no handsets lifted and for each handset in turn lifted?

Scott, have you tried swapping around the handsets? Just a bit more
evidence.

No, but I thought of that as I was watching Netflix. I also found out
if I hold the line the buzzing increases !!! Maybe I am acting as an
aerial.


OK - are you going to try swapping? Is that you holding the 'phone or
the power cable? It'd be interesting to see a sketch of the network of
phones - showing any broadband filters. Is each extension used for
phone only, broadband only, or both? Does any of the network still
include a third, "bell" wire?

PA

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Default *Five* wire overhead mains cables

On 20/04/2021 14:08, The Natural Philosopher wrote:
On 19/04/2021 16:09, newshound wrote:
On 17/04/2021 11:11, The Natural Philosopher wrote:
On 17/04/2021 09:11, Andy Burns wrote:
ARW wrote:

Andy Burns wrote:

ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77
WTF?

insulating spacers to stop the phases getting too close in the wind?

Yep. I see it when I look further down.
And a customer sent me this last week
https://www.youtube.com/watch?v=uUow...tishPath%C3%A9


But those "X" spacers which the commentator says are to stop them
shorting the system, are on wires of the same phase!

they are to stop wires *chafing*,when on the same phase.


No, the X spacers for the four conductors on each phase of supergrid
lines give the overall conductor an electric field distribution more
like a larger diameter conductor, reducing the corona losses.


No, that's what 4 wires instead of 1 does... the spacers are to *keep*
them 4 wires...:-) imagine 4 wires that close in a gust of wind...


I guess
they also reduce the conductor temperature at a given current from the
level if all the aluminium conductor was wrapped around a single steel
(load carrying) core.


Mmm. greater surface to volume? nah. I think that works the other way
cross section goes up as radius squared but area only goes up as radius.

Have I got that right - the cross section of 4 wires is the same as a
single wire twice the diameter so surface area of single wire is 2 pi D
whereas its 4 x pi x D for 4 wires...-oh ok, you are right. All other
things being equal that should run cooler - although from memory they
don't mind them getting hot, its the resistance they don't like.


Conductor temperature has other significance. They can (and do) carry
more current in the winter than the summer while staying within the
"sag" allowance from thermal expansion. A rare example of Sod getting it
wrong.


Also factor in the mundane. Nice to stock just one kind of overhead
cable and get 4 x current carrying capacity with a few spacers and
different insulators.


You could be right although I suspect that each supergrid voltage has
its own optimised cable. I'm pretty sure the individual insulator
elements in 275kV and 400kV are different (as well as the stringers
being longer for 400).
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On Friday, April 16, 2021 at 3:57:31 PM UTC+1, NY wrote:
I'm used to seeing three-wire (three phases) overhead mains wiring from
poles along a street. Sometimes you get four-wire (three phases plus
neutral). Modern wiring is a single larger cable which is the three (or
four) wires twisted together. In each case, two wires (between two phases,
or one phase and neutral) go to each house, with a different phase for each
house or group of houses.

But I'm mystified about five-wire mains. As far as I could see, all five
wires were the same thickness and were each fastened to the same type of
insulator on the wooden poles - so probably not three-wire mains and
telephone.

What would the fifth wire be used for?


L1, L2, L3, Street Lighting, N


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The Natural Philosopher wrote:

Roger Hayter wrote:

And don't the fibre cables include a steel rope to take the tension?


yes. and a copper pair, too.


Yes, drop wires that they've already installed contain a copper pair,
but will they continue with that now they're going fibre-only and using
voip? I'd have thought they'd want to remove all temptation for the
thieves.

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On Wednesday, 21 April 2021 at 08:07:26 UTC+1, Andy Burns wrote:
The Natural Philosopher wrote:
Roger Hayter wrote:

And don't the fibre cables include a steel rope to take the tension?


yes. and a copper pair, too.

Yes, drop wires that they've already installed contain a copper pair,
but will they continue with that now they're going fibre-only and using
voip? I'd have thought they'd want to remove all temptation for the
thieves.


I have seen two different types of drop cable being installed recently. One has
a copper pair alongside the fibre cable. The main strength element appears
to be kevlar or something similar. The other drop cable has nothing metallic.
My sister in law has the type with a copper pair and was recently told by BT
that she would be moved to VoIP and the copper service discontinued. This
is a rural location with long unreliable copper lines.

I don't know how the multi-fibre cables used for long overhead runs are
strengthened, but whatever it is works well at holding up fallen trees.

John

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Default *Five* wire overhead mains cables

On 20/04/2021 21:40, newshound wrote:
On 20/04/2021 14:08, The Natural Philosopher wrote:
On 19/04/2021 16:09, newshound wrote:
On 17/04/2021 11:11, The Natural Philosopher wrote:
On 17/04/2021 09:11, Andy Burns wrote:
ARW wrote:

Andy Burns wrote:

ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77
WTF?

insulating spacers to stop the phases getting too close in the wind?

Yep. I see it when I look further down.
And a customer sent me this last week
https://www.youtube.com/watch?v=uUow...tishPath%C3%A9


But those "X" spacers which the commentator says are to stop them
shorting the system, are on wires of the same phase!

they are to stop wires *chafing*,when on the same phase.


No, the X spacers for the four conductors on each phase of supergrid
lines give the overall conductor an electric field distribution more
like a larger diameter conductor, reducing the corona losses.


No, that's what 4 wires instead of 1 does... the spacers are to *keep*
them 4 wires...:-) imagine 4 wires that close in a gust of wind...


I guess
they also reduce the conductor temperature at a given current from
the level if all the aluminium conductor was wrapped around a single
steel (load carrying) core.


Mmm. greater surface to volume? nah. I think that works the other way
cross section goes up as radius squared but area only goes up as radius.

Have I got that right - the cross section of 4 wires is the same as a
single wire twice the diameter so surface area of single wire is 2 pi
D whereas its 4 x pi x D for 4 wires...-oh ok, you are right. All
other things being equal that should run cooler - although from memory
they don't mind them getting hot, its the resistance they don't like.


Conductor temperature has other significance. They can (and do) carry
more current in the winter than the summer while staying within the
"sag" allowance from thermal expansion. A rare example of Sod getting it
wrong.


Also factor in the mundane. Nice to stock just one kind of overhead
cable and get 4 x current carrying capacity with a few spacers and
different insulators.


You could be right although I suspect that each supergrid voltage has
its own optimised cable. I'm pretty sure the individual insulator
elements in 275kV and 400kV are different (as well as the stringers
being longer for 400).


That is a straw man. times 4 conductors increase powwer capacity *at the
same voltage*

Its a neat way to up the power without having to increase voltages which
would probably in the end cost more


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

Marshall McLuhan

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On 21/04/2021 08:07, Andy Burns wrote:
The Natural Philosopher wrote:

Roger Hayter wrote:

And don't the fibre cables include a steel rope to take the tension?


yes. and a copper pair, too.


Yes, drop wires that they've already installed contain a copper pair,
but will they continue with that now they're going fibre-only and using
voip?* I'd have thought they'd want to remove all temptation for the
thieves.

i expect they will in time drop them, yes


--
it should be clear by now to everyone that activist environmentalism
(or environmental activism) is becoming a general ideology about humans,
about their freedom, about the relationship between the individual and
the state, and about the manipulation of people under the guise of a
'noble' idea. It is not an honest pursuit of 'sustainable development,'
a matter of elementary environmental protection, or a search for
rational mechanisms designed to achieve a healthy environment. Yet
things do occur that make you shake your head and remind yourself that
you live neither in Joseph Stalins Communist era, nor in the Orwellian
utopia of 1984.

Vaclav Klaus
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Default *Five* wire overhead mains cables

In article , John
Walliker wrote:
On Wednesday, 21 April 2021 at 08:07:26 UTC+1, Andy Burns wrote:
The Natural Philosopher wrote:
Roger Hayter wrote:

And don't the fibre cables include a steel rope to take the tension?

yes. and a copper pair, too.

Yes, drop wires that they've already installed contain a copper pair,
but will they continue with that now they're going fibre-only and using
voip? I'd have thought they'd want to remove all temptation for the
thieves.


I have seen two different types of drop cable being installed recently.
One has a copper pair alongside the fibre cable. The main strength
element appears to be kevlar or something similar. The other drop cable
has nothing metallic. My sister in law has the type with a copper pair
and was recently told by BT that she would be moved to VoIP and the
copper service discontinued. This is a rural location with long
unreliable copper lines.



our 'copper' exchange is due to be closed in 2016.

I don't know how the multi-fibre cables used for long overhead runs are
strengthened, but whatever it is works well at holding up fallen trees.


John


--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle
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