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?

On 16/04/2021 15:57, 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?

Telephones - well it is around here.

PA

"Peter Able" wrote in message
...
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

With the phone wires on (as far as I could see) the same brown porcelain
insulators as the 240 V mains wires?


This is the wiring https://goo.gl/maps/7TY9tJ2LNZfzEGE46 and
https://goo.gl/maps/YRgYsyz7K75p3KUZ6: the latter shows a separate phone
wire swapping from below the five mains wires on the nearest post to the
above them on the next post, which looks as if it could cause if the
insulated phone cable was repeatedly blown against the un-insulated mains
wires, eventually taking the phone insulation off and shorting the mains
wires.

On Friday, April 16, 2021 at 4:25:24 PM UTC+1, NY wrote:
"Peter Able" wrote in message
...
On 16/04/2021 15:57, 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?

Telephones - well it is around here.
With the phone wires on (as far as I could see) the same brown porcelain
insulators as the 240 V mains wires?


This is the wiring https://goo.gl/maps/7TY9tJ2LNZfzEGE46 and
https://goo.gl/maps/YRgYsyz7K75p3KUZ6: the latter shows a separate phone
wire swapping from below the five mains wires on the nearest post to the
above them on the next post, which looks as if it could cause if the
insulated phone cable was repeatedly blown against the un-insulated mains
wires, eventually taking the phone insulation off and shorting the mains
wires.
Only four wires coming from the pole mounted transformer, the fifth wire just seems to go from pole to pole down the street

On 16/04/2021 16:25, NY wrote:
....
This is the wiring https://goo.gl/maps/7TY9tJ2LNZfzEGE46 ...

The top three are the three phases. The bottom one is neutral and the
one between, which, if you look carefully is not insulated, is earth.

It was a common arrangement in some areas.

--
Colin Bignell

In article , nightjar
writes
On 16/04/2021 16:25, NY wrote:
...
This is the wiring https://goo.gl/maps/7TY9tJ2LNZfzEGE46 ...

The top three are the three phases. The bottom one is neutral and the
one between, which, if you look carefully is not insulated, is earth.

It was a common arrangement in some areas.

We have an extra cable, not insulated around here which is a low
voltage data signal carrier.
--
bert

On 16/04/2021 19:28, bert wrote:
In article , nightjar
writes
On 16/04/2021 16:25, NY wrote:
...
This is the wiring https://goo.gl/maps/7TY9tJ2LNZfzEGE46 ...

The top three are the three phases. The bottom one is neutral and the
one between, which, if you look carefully is not insulated, is earth.

It was a common arrangement in some areas.

We have an extra cable, not insulatedÂ* around here which is a low
voltage data signal carrier.

The setup shown is typical of pre-war rural area electricity
distribution systems, which are as I describe.


--
Colin Bignell

On 16/04/2021 16:25, NY wrote:
"Peter Able" wrote in message
...
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

With the phone wires on (as far as I could see) the same brown porcelain
insulators as the 240 V mains wires?


This is the wiring https://goo.gl/maps/7TY9tJ2LNZfzEGE46 and
https://goo.gl/maps/YRgYsyz7K75p3KUZ6: the latter shows a separate phone
wire swapping from below the five mains wires on the nearest post to the
above them on the next post, which looks as if it could cause if the
insulated phone cable was repeatedly blown against the un-insulated
mains wires, eventually taking the phone insulation off and shorting the
mains wires.

Now, with an image, there's something to go on.

Looking at the second link, the fourth cable from the top terminates at
a house further on to right, and at a pole further to the left. It
looks to be thinner, and is not obviously driven from 3-phase drives?

So who knows?

And wouldn't you - even if was only meant for for this or that, use an
cable insulator/anti-rubbing item of the same kind as already in use in
that area?

PA

On 16/04/2021 16:25, NY wrote:
"Peter Able" wrote in message
...
On 16/04/2021 15:57, 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?

P1, P2, P3, N, E

Telephones - well it is around here.

With the phone wires on (as far as I could see) the same brown porcelain
insulators as the 240 V mains wires?

This is the wiring https://goo.gl/maps/7TY9tJ2LNZfzEGE46 and
https://goo.gl/maps/YRgYsyz7K75p3KUZ6: the latter shows a separate phone
wire swapping from below the five mains wires on the nearest post to the
above them on the next post, which looks as if it could cause if the
insulated phone cable was repeatedly blown against the un-insulated
mains wires, eventually taking the phone insulation off and shorting the
mains wires.

It is an optical illusion the phone line is below the mains wiring (and
in prehistory the mains was probably insulated but not any more). Ours
failed by having strips of the rubber insulation fall off and short
adjacent phases in bad wet weather with much arcing and sparking.

The phone line goes from low position on an electric pole to a higher
phone pole set back from the electricity lines so there is no danger of
them rubbing together. Phone is below mains wiring on our poles.

My own village was wired about like this until the insulation fallign
off kept bring the entire network down. It was replaced by three core
aluminium conductors platted around a steel hawser down the middle.

The new wiring proved strong enough to resist a tree falling across it
although the supporting poles ended up like bananas and one side of the
street was disconnected from supply. I have a picture of it somewhere.
My hedge has still not quite recovered from the damage.

The poles now have little plaques on "unsafe: do not climb".

--
Regards,
Martin Brown

In article , Peter Able wrote:
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

PA

In the Uk you can't mix mains and telephone. % wire 3 pases, neutral &
earth.

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

"charles" wrote in message
...
In article , Peter Able
wrote:
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

PA

In the UK you can't mix mains and telephone. 5 wire 3 phases, neutral &
earth.


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?

On Fri, 16 Apr 2021 18:46:38 +0100, "NY" wrote:

"charles" wrote in message
...
In article , Peter Able
wrote:
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

PA

In the UK you can't mix mains and telephone. 5 wire 3 phases, neutral &
earth.

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?

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

On 16/04/2021 19:27, Scott wrote:
On Fri, 16 Apr 2021 18:46:38 +0100, "NY" wrote:

"charles" wrote in message
...
In article , Peter Able
wrote:
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

PA

In the UK you can't mix mains and telephone. 5 wire 3 phases, neutral &
earth.


Depends what you mean by mix. Both around here - and in NY's links -
you can see telephone lines sharing the poles.


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?

There'll always be some imbalance. Different loads, and not every third
house on the same phase.


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.

They do, but in both wires - so that's ok (theoretically)

PA

"Scott" wrote in message
...
On Fri, 16 Apr 2021 18:46:38 +0100, "NY" wrote:

"charles" wrote in message
...
In article , Peter Able
wrote:
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

PA

In the UK you can't mix mains and telephone. 5 wire 3 phases, neutral &
earth.

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?

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

Nope, because they are twisted pairs.

On 16 Apr 2021 at 19:27:27 BST, "Scott"
wrote:

On Fri, 16 Apr 2021 18:46:38 +0100, "NY" wrote:

"charles" wrote in message
...
In article , Peter Able
wrote:
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

PA

In the UK you can't mix mains and telephone. 5 wire 3 phases, neutral &
earth.

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?

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

Our electricity and telephone come from the same pole outside our house.
Openreach technicians say it is undesirable, but there is really nowhere else
to put a pole without the mains and telephone drop wires interfering with each
other. I've never seen a telephone cable on an 11kV pole though!

--
Roger Hayter

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.

--
*It ain't the size, it's... er... no, it IS ..the size.

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

In article , NY wrote:
"charles" wrote in message
...
In article , Peter Able
wrote:
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

PA

In the UK you can't mix mains and telephone. 5 wire 3 phases, neutral &
earth.


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.

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

On Fri, 16 Apr 2021 20:36:02 +0100, charles
wrote:

In article , NY wrote:
"charles" wrote in message
...
In article , Peter Able
wrote:
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

PA

In the UK you can't mix mains and telephone. 5 wire 3 phases, neutral &
earth.

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.

On Fri, 16 Apr 2021 18:46:38 +0100, 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?

A neutral is required - the houses will have a single phase supply, so
will connect to one phase and neutral. Where you won't see a neutral is
on the HV lines - the neutral is created at the transformer.
A separate earth cable on overhead cabling is unusual - most often it's
PME (so combined N/E) or TT (an earth rod at the house).

It doesn't look like the earth cable in this example actually goes to
most of the houses. https://goo.gl/maps/QGxRssmS2mkMJuKV8 and https://
goo.gl/maps/YEC7HKgHGvnC1Qy57 shows only two wires over the road to the
house.

The fifth wire terminates here https://goo.gl/maps/DqQoYJcoJCVptT2E7 -
you can see that only four wires continue to the last pole, with the
second from bottom missing.

Where the line branches at Chapel Lane, there are again only four wires,
and there's another four-wire branch just past at https://goo.gl/maps/
DqQoYJcoJCVptT2E7 . And the line ends here https://goo.gl/maps/
zovrrTaZbFnAePZP7 - where you can clearly see that the underground cable
does not connect to the earth wire, only the phases and neutral.

So I think there's a good chance this earth wire is mostly, or even
completely, redundant. It's possible that it's been converted to PME but
the separate earth wire not been removed. .

Mike

On 16/04/2021 23:02, Mike Humphrey wrote:
On Fri, 16 Apr 2021 18:46:38 +0100, 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?

A neutral is required - the houses will have a single phase supply, so
will connect to one phase and neutral. Where you won't see a neutral is
on the HV lines - the neutral is created at the transformer.
A separate earth cable on overhead cabling is unusual - most often it's
PME (so combined N/E) or TT (an earth rod at the house).

Are you saying that overhead mains wiring is *always* 4-wire (or 5-wire
if there's a PE), with every house connected to one phase and neutral?
And not houses connected to two of the phases? I *thought* I'd seen
three wires rather than 4 in some cases. But I may well be
mis-remembering it.

On 16/04/2021 18:46, NY wrote:
"charles" wrote in message
...
In article , Peter Able
wrote:
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

PA

In the UK you can't mix mains and telephone. 5 wire 3 phases, neutral &
earth.


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?

yes.

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

it aint no silly 110v either. its 230v.,


--
No Apple devices were knowingly used in the preparation of this post.

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.

That sounds like a recipe for disaster to me. Hum induced voltages and
damage putting dangerous voltages up a phone line.
Brian

--

This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Peter Able" wrote in message
...
On 16/04/2021 15:57, 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?

Telephones - well it is around here.

PA

On 17/04/2021 08:29, Brian Gaff (Sofa) wrote:
That sounds like a recipe for disaster to me. Hum induced voltages and
damage putting dangerous voltages up a phone line.
Brian


Not at all. Induction makes little difference to our, notionally
balanced, telephone network and the anchor points are well below the
power cabling. There are several examples of this practice in the
Google Map views the OP offered us.

It is instructive to connect a phone line to a spectrum analyser and
oscilloscope. When looking at either wire there is masses of pickup -
predominantly of the Medium Wave - but some 50Hz, too.
If you then couple both lines via a balun to the spectrum
analyser/oscilloscope, you - thankfully - see way, way, way less
unwanted stuff.

PA

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

On 16/04/2021 16:47, 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

See photo here (it's not good, and you'll have to zoom in a bit)
https://ibb.co/7Cs99M2

A temporary 500kW generator was required recently to cover for some work
on a nearby substation. It was connected up to the overhead lines
nearby. There were five cables from the generator to the lines. The
upper three were connected to, I expect, the three live phases (they are
the upper three cables with the yellow insulated connectors). There were
two further connectors (uninsulated?). They are the lower two in the
photo, and both appear to be connected to the fourth line( below the
three live phases), which I assume is the neutral. Would those two
connections be neutral and earth from the generator to make a common
neutral/earth connection?

--

Jeff

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

On 16/04/2021 15:57, 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?

Jump a couple of meters down the road and then you see this

https://goo.gl/maps/WQQhtqdtJCyLf6c77

WTF?

--
Adam

ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77

WTF?

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

Many moons ago down a country lane in Cornwall, I was young kid and we all
were stopped in our tracks by a team with a cherry picker doing something on
the wooden pole at the side of the road. I think my dad got out to stretch
his legs while we waited, and asked one of the blokes there why there were
so many wires and apparently all bundled together every so often. They told
him one of them was a steel wire to help stop the others stretching and did
nothing else.
Brian

--

This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Andy Burns" wrote in message
...
ARW wrote:

https://goo.gl/maps/WQQhtqdtJCyLf6c77

WTF?

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

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

--
Adam

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!

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!



https://www.youtube.com/watch?v=QLl9...l=User_Unknown

--
Adam

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

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

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

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

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

--
Adam

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