The Natural Philosopher wrote:
On 09/07/18 20:44, John Rumm wrote:


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.

That last is a bit ambiguous. I take it you you mean a two wire 2 phase
11Kv line like we had to supply us and a neighbour a field or two along
the road, from the transformer it was two wire 240V pole mounted along the
field boundarys to each property. That was single phase live and neutral
with neutral grounded to earth at each pole using an uninsulated stranded
cable into the ground and presumably a buried earth rod. Not sure if that
is pure copper or something else but it has gathered a greenish tinge in
the 54 years since I watched the SWEB workers dig holes by hand for the
poles.
No fancy augers back then. Each pole then had a red enabled plate with the
legend PME affixed to it .

GH

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.

Aren't anglers warned to be aware of the danger of accidentally touching
them with their fishing lines while casting? I think I've seen such
signs around here.

"Tufnell Park" wrote in message
news
Any 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.

Only if it's somehow rotated on your screen. The image I posted is
landscape, wider that it is tall, with a vertical wooden post, three
horizontal electricity wires, one below another, and one horizontal BT cable
some distance below it. The pole really *is* multi-purpose because it also
has a street light on

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

That's what I would expect. Here's a photo of the house end of those cables:

https://s22.postimg.cc/zaem5elyp/20180710_111448.jpg (yes I know the thick
cable running down the wall from the insulators needs another staple to
fasten it to the wall near where it bends from vertical to horizontal)

https://s22.postimg.cc/keg2xvfpt/20180710_111504.jpg is the overall view of
house and pole, showing the street light at the bottom left of picture.

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.

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

They replaced the transformer nearby and overhead wires to a few houses
on the pole outside our house five years ago, and it still also carries
the phone wires to the same houses. But then it is rather hard to see
where they could put another pole.


--

Roger Hayter

On Mon, 09 Jul 2018 22:49:34 +0100, Graham. wrote:

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

I bet that wiped out TMS.

B-) Broken connection from line to the wire taking the power over
the top of the pole. Bet who ever was on that phase was having some
interesting supply variations. Looks to be 33 kV as well not 11 kV.

--
Cheers
Dave.

On Mon, 9 Jul 2018 09:20:32 +0100, "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.

I don't think 400KV is insulated so why on earth (excuse the pun)
would 230 or 240V be insulated?

On 10/07/2018 08:28, The Natural Philosopher wrote:
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.

True, for a proper 3ph load. However if its a domestic supply, then
individual properties would typically only receive one phase and a
neutral (derived at the transformer).

(I am assuming we are looking at the LV side of the supply between
transformer and house here. If that is the case you would normally
expect 4 wires if all the phases are present with a neutral).

I have never seen a two
phase plus neutral overhead feed and can't see any technical reason for it

If you have more potential load than would be supported on one phase,
and its close enough to do the run at LV, then it might make sense.

All this is only conjecture based on what we can see in the photo
obviously.

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

Yup same here... about a dozen properties fed from one (twin) pole
mounted transformer. A while back they re-cabled the LV side and went
from 4 air spaced uninsulated conductors, to a twisted bundle of
insulated ones.

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




--
Cheers,

John.

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

"Scott" wrote in message
...
On Mon, 9 Jul 2018 09:20:32 +0100, "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.

I don't think 400KV is insulated so why on earth (excuse the pun)
would 230 or 240V be insulated?

I suppose it makes more sense to insulate 240 V overhead wiring because
there is a greater chance of a high vehicle striking it, a tree falling on
it (without breaking the wire and therefore the circuit) or a builder coming
into contact with it as it approaches a house. Higher voltage lines are
higher off the ground (especially pylon wiring) and so is almost impossible
for a tall vehicle or a tree to come into contact with it. 11 kV and 33 kV
are borderline: higher than 240 V, but still just about low enough for long
fishing rods to come into contact with it (or more likely, for arcing to
occur) - hence the warning signs on river and canal banks where these wires
cross.


I presume that when the electricity company put temporary sleeving around
the wires where they approach the insulators on a house when building work
is being done, the sleeving has a slit along it (like the foam insulation
that is put around water pipes) so it can be put onto the wires without
having to disconnect them from the house insulators and insert the wire into
the sleeve.

On 10/07/2018 14:26, Scott wrote:
On Mon, 9 Jul 2018 09:20:32 +0100, "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.

I don't think 400KV is insulated so why on earth (excuse the pun)
would 230 or 240V be insulated?

Because its lower and more easily accessible, and also connects directly
to a customer's property.


--
Cheers,

John.

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

Scott wrote:
On Mon, 9 Jul 2018 09:20:32 +0100, "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.

I don't think 400KV is insulated so why on earth (excuse the pun)
would 230 or 240V be insulated?


400KV cables tend to be well above the height that window cleaners with
ladders,aerial riggers, roofers and house painters ,gardeners trimming
Wisteria or Ivy and various other tasks that take place around a building
which the low voltage services are also located around at similar height to
the gutters.

GH

On 09/07/2018 22:40, Tufnell Park wrote:
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.

You can't 'balance' out a single 240 volt phase and neutral feeding
several houses by using different phases because there aren't any
spare !.

Only larger premises like businesses ever had 3-phase so your
suggestion that houses with storage heaters would 'have an
extra phase' is just plain wrong. In the states maybe, but their
system is different.

On 10/07/2018 10:27, Martin Brown wrote:
Resistive electric heating is about the most expensive possible form of
space heating that there is.

Well in about 30 years times people with poorly insulated houses
and without a means to burn logs or similar, are going to have start
getting used to living like their ancestors did, and huddle round
one source of heat in one room.

On 10/07/2018 15:16, NY wrote:
Higher voltage lines are higher off the ground (especially pylon wiring)
and so is almost impossible for a tall vehicle or a tree to come into
contact with it. 11 kV and 33 kV are borderline:

err, during the recent hot spell I saw plenty of 11 and 33 KV lines here
in Sussex sagging ominously across farmland. Wouldn't want to be on top
of a load hay or straw bales going under them.

On 09/07/2018 22:51, Steve Walker wrote:
Creosote is still the preferred option for telegraph and power poles AFAIK.

BT and farmers have exemption from the EU nanny state rules that
stop me from buying, storing or using it.

"Andrew" wrote in message
news
Only larger premises like businesses ever had 3-phase so your
suggestion that houses with storage heaters would 'have an
extra phase' is just plain wrong. In the states maybe, but their
system is different.

That's why I queried it. I know that US houses often have a 220 V feed as
well as a 110 V feed, to drive power-hungry appliances like tumble driers,
cookers and air-conditioning units, in order to avoid needing extra-thick
wires to allow 2x current to compensate for 1/2 voltage, compared with
European 220/240V systems. I think it is one phase fed from a transformer
with a centre tap, rather than a true two-phase supply (where there is a 120
degree phase difference between each of the phases and neutral). I believe
the 220 V connection is always hard-wired rather than via a plug and socket,
though I could be wrong on that.

But in the UK, I'd be very surprised if an ordinary house (not a business or
a farm, now or in the past) ever had more than one phase.

On 10/07/18 15:11, John Rumm wrote:
On 10/07/2018 08:28, The Natural Philosopher wrote:
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.

True, for a proper 3ph load. However if its a domestic supply, then
individual properties would typically only receive one phase and a
neutral (derived at the transformer).

Depoends . Her often its one traanformer per house and taht is slung as
a part delta across two 11kv phases.

One side of the secondary is then earthed

Hres a fun one for you. 11KV 3ph underground, and 240V oveheads to the
houses




(I am assuming we are looking at the LV side of the supply between
transformer and house here. If that is the case you would normally
expect 4 wires if all the phases are present with a neutral).

I have never seen a two phase plus neutral overhead feed and can't see
any technical reason for it

If you have more potential load than would be supported on one phase,
and its close enough to do the run at LV, then it might make sense.


I guess.


All this is only conjecture based on what we can see in the photo
obviously.

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

Yup same here... about a dozen properties fed from one (twin) pole
mounted transformer. A while back they re-cabled the LV side and went
from 4 air spaced uninsulated conductors, to a twisted bundle of
insulated ones.

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






--
Outside of a dog, a book is a man's best friend. Inside of a dog it's
too dark to read.

Groucho Marx

On 10/07/18 16:21, NY wrote:
"Andrew" wrote in message
news
Only larger premises like businesses ever had 3-phase so your
suggestion that houses with storage heaters would 'have an
extra phase' is just plain wrong. In the states maybe, but their
system is different.

That's why I queried it. I know that US houses often have a 220 V feed
as well as a 110 V feed, to drive power-hungry appliances like tumble
driers, cookers and air-conditioning units, in order to avoid needing
extra-thick wires to allow 2x current to compensate for 1/2 voltage,
compared with European 220/240V systems. I think it is one phase fed
from a transformer with a centre tap, rather than a true two-phase
supply (where there is a 120 degree phase difference between each of the
phases and neutral). I believe the 220 V connection is always hard-wired
rather than via a plug and socket, though I could be wrong on that.

But in the UK, I'd be very surprised if an ordinary house (not a
business or a farm, now or in the past) ever had more than one phase.

I've seen single phase and I've seen 3 phase but I have NEVER seen a 2
phase installation.

I dont think its on offer.


--
"In our post-modern world, climate science is not powerful because it is
true: it is true because it is powerful."

Lucas Bergkamp

On 10/07/18 16:23, The Natural Philosopher wrote:
Hres a fun one for you. 11KV 3ph underground, and 240V oveheads to the
houses

https://vps.templar.co.uk/Odds%20and%20Ends/leccy.jpg

--
"In our post-modern world, climate science is not powerful because it is
true: it is true because it is powerful."

Lucas Bergkamp

On 10/07/18 16:21, NY wrote:
"Andrew" wrote in message
news
Only larger premises like businesses ever had 3-phase so your
suggestion that houses with storage heaters would 'have an
extra phase' is just plain wrong. In the states maybe, but their
system is different.

That's why I queried it. I know that US houses often have a 220 V feed
as well as a 110 V feed, to drive power-hungry appliances like tumble
driers, cookers and air-conditioning units, in order to avoid needing
extra-thick wires to allow 2x current to compensate for 1/2 voltage,
compared with European 220/240V systems. I think it is one phase fed
from a transformer with a centre tap, rather than a true two-phase
supply (where there is a 120 degree phase difference between each of the
phases and neutral). I believe the 220 V connection is always hard-wired
rather than via a plug and socket, though I could be wrong on that.

A 2 phase supply does not have to be 120 degrees. It could be 180 (which
is basically centre tapped). It could be 90 degrees - a system used in
London in the early 1900s which persisted for quite a part of that
century (my Dad met it).

You can even get special transformers to interface 90 degree systems to
120 3ph systems ("Scott connection" and "LeBlanc Connection"
transformers IIRC).

In some of my readings, very occasionally, the "240V" socket in a US
house might be derived from 2 120-degree phases, so actually around 207V
(120V x sqrt(3)). Not sure how reliable my info was...


But in the UK, I'd be very surprised if an ordinary house (not a
business or a farm, now or in the past) ever had more than one phase.

Andrew wrote:
On 10/07/2018 15:16, NY wrote:
Higher voltage lines are higher off the ground (especially pylon wiring)
and so is almost impossible for a tall vehicle or a tree to come into
contact with it. 11 kV and 33 kV are borderline:

err, during the recent hot spell I saw plenty of 11 and 33 KV lines here
in Sussex sagging ominously across farmland. Wouldn't want to be on top
of a load hay or straw bales going under them.

There has been a rolling programme of installing taller poles to raise the
heights of such lines for some years now as it was recognised that what was
a safe clearance for a Grey Fergie towing a 1950s style trailer was no
longer adequate now tractors and Combines are the size of a small Bungalow.

Saw some in place the other day. Usual method is to install new poles
close to the existing ones with the part closest to the conductors wrapped
in polyethylene. Later they come back raise the cables on temporary
supports add the new cross arm and insulators and lower the cables back
onto them then remove the old pole.
In some cases they may do this with the cables live.

GH

"Marland" wrote in message
...
Andrew wrote:
err, during the recent hot spell I saw plenty of 11 and 33 KV lines here
in Sussex sagging ominously across farmland. Wouldn't want to be on top
of a load hay or straw bales going under them.

Saw some in place the other day. Usual method is to install new poles
close to the existing ones with the part closest to the conductors
wrapped
in polyethylene. Later they come back raise the cables on temporary
supports add the new cross arm and insulators and lower the cables back
onto them then remove the old pole.
In some cases they may do this with the cables live.

I'm not sure you'd get me working on wires that are live at 33 kV, even with
parts wrapped in polythene.

And you *certainly* wouldn't get me working on live 400 kV lines, a long way
up in the air, having to be delivered to the line in an insulated cage
suspended from a helicopter or cherry-picker, with arcing and fizzing as the
cage gets close to the lines. Those guys deserve every penny they earn.

In article ,
The Natural Philosopher wrote:
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

eh?

Once the supply is taken down to 240v (approx) it is distributed as 3
phases AND neutral which comes from the star point on tehntransmoform.

Roadside on-pole local distribution is 3 phases and neutral.

Feed into this house (from an undergound supply) is 2 phases and neutral.

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

In article , NY
wrote:
"Andrew" wrote in message
news
Only larger premises like businesses ever had 3-phase so your
suggestion that houses with storage heaters would 'have an extra phase'
is just plain wrong. In the states maybe, but their system is different.

That's why I queried it. I know that US houses often have a 220 V feed as
well as a 110 V feed, to drive power-hungry appliances like tumble
driers, cookers and air-conditioning units, in order to avoid needing
extra-thick wires to allow 2x current to compensate for 1/2 voltage,
compared with European 220/240V systems. I think it is one phase fed
from a transformer with a centre tap, rather than a true two-phase
supply (where there is a 120 degree phase difference between each of the
phases and neutral). I believe the 220 V connection is always hard-wired
rather than via a plug and socket, though I could be wrong on that.

But in the UK, I'd be very surprised if an ordinary house (not a business
or a farm, now or in the past) ever had more than one phase.

I don't know when electricerry was put in this house (built in 1911) but it
has a two phase supply.

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

On 10/07/2018 15:31, Andrew wrote:
On 09/07/2018 22:40, Tufnell Park wrote:
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.

You can't 'balance' out a single 240 volt phase and neutral feeding
several houses by using different phases because there aren't any
spare !.

I didn't say you could do that. What i said was; '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'.
Some houses had 3 phase supplies if the 'load' demanded it.

This was done routinely when i worked for a UK REC in the 60's/70's



Only larger premises like businesses ever had 3-phase so your
suggestion that houses with storage heaters would 'have an
extra phase' is just plain wrong. In the states maybe, but their
system is different.

If you are referring to the UK you are just plain wrong. See above!

"Scott" wrote in message
...
On Mon, 9 Jul 2018 09:20:32 +0100, "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.

I don't think 400KV is insulated

Correct.

so why on earth (excuse the pun)
would 230 or 240V be insulated?

Because at least at the house end, with the line between
the pole and the house, there can be someone using a
ladder to get to the gutter etc at times or pruning trees.

On 10/07/18 18:39, charles wrote:
In article ,
The Natural Philosopher wrote:
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

eh?

Once the supply is taken down to 240v (approx) it is distributed as 3
phases AND neutral which comes from the star point on tehntransmoform.

Roadside on-pole local distribution is 3 phases and neutral.

Feed into this house (from an undergound supply) is 2 phases and neutral.


Well at the loast 500 yards, yes, its a 4 wire setup.

I was talking about 11kv and up.


--
All political activity makes complete sense once the proposition that
all government is basically a self-legalising protection racket, is
fully understood.

Andrew wrote
NY wrote

Higher voltage lines are higher off the ground (especially pylon wiring)
and so is almost impossible for a tall vehicle or a tree to come into
contact with it. 11 kV and 33 kV are borderline:

err, during the recent hot spell I saw plenty of 11 and 33 KV lines here
in Sussex sagging ominously across farmland. Wouldn't want to be on top of
a load hay or straw bales going under them.

We dont get that here and it gets a hell of a lot hotter here than it does
there.

On Wed, 11 Jul 2018 04:55:10 +1000, cantankerous geezer Rot Speed blabbered,
again:


err, during the recent hot spell I saw plenty of 11 and 33 KV lines here
in Sussex sagging ominously across farmland. Wouldn't want to be on top of
a load hay or straw bales going under them.

We don¢t get that here and it gets a hell of a lot hotter here than it does
there.

You got up at about 4 o'clock in Australia again, you abnormal idiot! So,
how many hours of sleep did you get? Three or four? Are you one of those
pathological idiots whose trolling is more important to them than anything
else? BG
--
Archibald Tarquin Blenkinsopp addressing Rot Speed:
"You really are a clueless pillock."
MID:

On 10/07/2018 19:40, The Natural Philosopher wrote:
On 10/07/18 18:39, charles wrote:
In article ,
Â*Â*Â* The Natural Philosopher wrote:
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

eh?

Once the supply is taken down to 240v (approx) it is distributed as 3
phases AND neutral which comes from the star point on tehntransmoform.

Roadside on-pole local distribution is 3 phases and neutral.

Feed into this house (from an undergound supply) is 2 phases and neutral.


Well at the loast 500 yards, yes, its a 4 wire setup.

I was talking about 11kv and up.

Having seen the later photos that NY posted recently, its pretty clear
this is the LV side. So two of the phases and neutral does actually look
pretty likely.


--
Cheers,

John.

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\================================================= ================/

On 09/07/2018 12:23, Huge wrote:
On 2018-07-09, Nightjar wrote:
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

They do take them away eventually. After a couple of months I called
to ask and they said they don't come out specifically to remove them,
they just do them as and when they happen to be in the area and have
time. It was about 6 months, IIRC.

As their cherry picker couldn't reach and they had to erect scaffolding
to put the sleeving up (to make it safe to erect scaffolding) I don't
expect them any time soon.


--
--

Colin Bignell