Is it illegal to park in front of a substation?

[James Wilkinson]

There's a substation near here with a short access driveway to it (room for one car). I often see a car parked in it. Is this illegal? Would the police tow it if I informed them? Or would they attempt to contact the owner at the registered address? What trouble would he get into?

[F Murtz]

Is he working in it?

[James Wilkinson]

No, he lives next door to it and sometimes has more cars than fit in his driveway.

[James Wilkinson]

On Sun, 31 Jul 2016 15:48:34 +0100, Jeff <je...@ukra.com> wrote:

> As it is almost certainly private property it would be a trespass, but
> the police would not be interested or have any power to do anything.

Wouldn't it be the same as parking in front of someone's drive and blocking them in? He's restricting access to the substation. If you called the police because someone had boxed you in, they would tow the car to allow you out of your drive wouldn't they?

--
Why is the front of an aeroplane called a cockpit?
If you have female pilots do you call it a pussypit?

[James Wilkinson]

On Sun, 31 Jul 2016 16:06:28 +0100, Jeff <je...@ukra.com> wrote:

> On 31/07/2016 15:57, James Wilkinson wrote:
>> On Sun, 31 Jul 2016 15:48:34 +0100, Jeff <je...@ukra.com> wrote:
>>
>>> On 31/07/2016 14:54, James Wilkinson wrote:
>>>> There's a substation near here with a short access driveway to it (room
>>>> for one car). I often see a car parked in it. Is this illegal? Would
>>>> the police tow it if I informed them? Or would they attempt to contact
>>>> the owner at the registered address? What trouble would he get into?
>>>
>>> As it is almost certainly private property it would be a trespass, but
>>> the police would not be interested or have any power to do anything.
>>
>> Wouldn't it be the same as parking in front of someone's drive and
>> blocking them in? He's restricting access to the substation. If you
>> called the police because someone had boxed you in, they would tow the
>> car to allow you out of your drive wouldn't they?
>

> They might if parked on the public highway but this is a different
> situation. it is like someone parking on your drive and blocking your
> garage.

So the police wouldn't respond if someone parked in my drive?! What do we pay these people for?

--
To determine how tightly to do up a nut, continue until you hear a crack, then back off half a turn.

[James Wilkinson]

On Sun, 31 Jul 2016 16:06:28 +0100, Jeff <je...@ukra.com> wrote:

> On 31/07/2016 15:57, James Wilkinson wrote:

>> On Sun, 31 Jul 2016 15:48:34 +0100, Jeff <je...@ukra.com> wrote:
>>
>>> On 31/07/2016 14:54, James Wilkinson wrote:
>>>> There's a substation near here with a short access driveway to it (room
>>>> for one car). I often see a car parked in it. Is this illegal? Would
>>>> the police tow it if I informed them? Or would they attempt to contact
>>>> the owner at the registered address? What trouble would he get into?
>>>
>>> As it is almost certainly private property it would be a trespass, but
>>> the police would not be interested or have any power to do anything.
>>
>> Wouldn't it be the same as parking in front of someone's drive and
>> blocking them in? He's restricting access to the substation. If you
>> called the police because someone had boxed you in, they would tow the
>> car to allow you out of your drive wouldn't they?
>>
>

> They might if parked on the public highway but this is a different
> situation. it is like someone parking on your drive and blocking your
> garage.

According to my title deeds, I own the road in front of my house but must allow the council to maintain it and let people drive along it. Parking ON my drive instead of in front of it is surely a worse offence?

--
Collectively, humans have spent almost 13,261 years watching the Gangnam Style video.

[Nightjar]

The chances are that the land the access road lies on is part of the
adjacent property and the electricity supply company has access rights
over it. Otherwise I would expect it to be fenced and gated right up to
the road, as many are. Where the electricity supply company has access
rights over land, they will, except in the case of an emergency,
normally be required to give advance notice of when they will need
access and the land owner can use the land at other times.

--
--

Colin Bignell

[damdu...@yahoo.co.uk]

>James Wilkinson wrote:
>> There's a substation near here with a short access driveway to it (room
>> for one car). I often see a car parked in it.

Thinks he is Elwood.
https://www.youtube.com/watch?v=6IUNgDG-T9A

G.harman

[James Wilkinson]

Oh. I take it any emergency access is probably just needing a bloke to be able to open the fence and turn off a breaker.

[James Wilkinson]

I notice the fat one didn't try it.

Were they hiding the car? A comment suggests it was a deleted scene.

--
Prostration - the act of exposing your genitalia to your god.

[Nightjar]

More likely to turn one on that has tripped and cannot be reset remotely.

However, when I worked for an Electricity Board, one emergency involved
making the whole substation area safe, so that the remains of a couple
of chaps who had tried to steal live 11kV cables could be removed.

--
--

Colin Bignell

[burfordTjustice]

On Sun, 31 Jul 2016 14:54:32 +0100
"James Wilkinson" <inv...@something.com> wrote:

> There's a substation

WTF?? Get your sub and go one about your business
leave other the fuck alone, damn busybodies.
Seems Hitler want you kind to report on friends/family/neighbors

[James Wilkinson]

Is that really an emergency? You can't save the two guys.

--
I went to buy some camoflage trousers the other day but I couldn't find any.

[pensive hamster]

On Monday, 1 August 2016 22:38:30 UTC+1, James Wilkinson wrote:

> On Mon, 01 Aug 2016 19:22:13 +0100, Nightjar wrote:
> > On 01-Aug-16 11:18 AM, James Wilkinson wrote:

[...]

> >> Oh. I take it any emergency access is probably just needing a bloke to
> >> be able to open the fence and turn off a breaker.
> >
> > More likely to turn one on that has tripped and cannot be reset remotely.
> >
> > However, when I worked for an Electricity Board, one emergency involved
> > making the whole substation area safe, so that the remains of a couple
> > of chaps who had tried to steal live 11kV cables could be removed.
>
> Is that really an emergency? You can't save the two guys.

Maybe if it interrupted the power supply in the area? Or
if members of the public might be upset seeing two dead
bodies?

[pensive hamster]

On Monday, 1 August 2016 22:38:30 UTC+1, James Wilkinson wrote:

> I went to buy some camoflage trousers the other day but I couldn't find any.

That's also a problem with the new stealth aircraft carriers.
They sometimes collide with each other. Several have been
sunk without trace.

[James Wilkinson]

They're mating.

--
Two men were talking.
"My son asked me what I did during the Sexual Revolution," said one.
"I told him I was captured early and spent the duration doing the dishes.

[James Wilkinson]

Reset the breaker, shove the dead body off with a big stick first if necessary.

> Or
> if members of the public might be upset seeing two dead
> bodies?

That's not an emergency.

[pensive hamster]

On Monday, 1 August 2016 23:15:14 UTC+1, James Wilkinson wrote:

> On Mon, 01 Aug 2016 22:45:07 +0100, pensive hamster wrote:
> > On Monday, 1 August 2016 22:38:30 UTC+1, James Wilkinson wrote:
> >> On Mon, 01 Aug 2016 19:22:13 +0100, Nightjar wrote:
> >> > On 01-Aug-16 11:18 AM, James Wilkinson wrote:
> > [...]
> >> >> Oh. I take it any emergency access is probably just needing a bloke to
> >> >> be able to open the fence and turn off a breaker.
> >> >
> >> > More likely to turn one on that has tripped and cannot be reset remotely.
> >> >
> >> > However, when I worked for an Electricity Board, one emergency involved
> >> > making the whole substation area safe, so that the remains of a couple
> >> > of chaps who had tried to steal live 11kV cables could be removed.
> >>
> >> Is that really an emergency? You can't save the two guys.
> >
> > Maybe if it interrupted the power supply in the area?
>
> Reset the breaker, shove the dead body off with a big stick first if necessary.
>
> > Or
> > if members of the public might be upset seeing two dead
> > bodies?
>
> That's not an emergency.

Oh yes it is, if they are middle-class parents who own shares
in the energy company.

[James Wilkinson]

That's a very unlikely scenario.

--
Does a pope shit in the woods? And if a pope shits in the woods and no-one is around, does he pebbledash?

[pensive hamster]

On Monday, 1 August 2016 23:40:47 UTC+1, James Wilkinson wrote:

> On Mon, 01 Aug 2016 23:34:34 +0100, pensive hamster wrote:
>
> > On Monday, 1 August 2016 23:15:14 UTC+1, James Wilkinson wrote:
> >> On Mon, 01 Aug 2016 22:45:07 +0100, pensive hamster wrote:
> >> > On Monday, 1 August 2016 22:38:30 UTC+1, James Wilkinson wrote:
> >> >> On Mon, 01 Aug 2016 19:22:13 +0100, Nightjar wrote:
> >> >> > On 01-Aug-16 11:18 AM, James Wilkinson wrote:
> >> > [...]
> >> >> >> Oh. I take it any emergency access is probably just needing a bloke to
> >> >> >> be able to open the fence and turn off a breaker.
> >> >> >
> >> >> > More likely to turn one on that has tripped and cannot be reset remotely.
> >> >> >
> >> >> > However, when I worked for an Electricity Board, one emergency involved
> >> >> > making the whole substation area safe, so that the remains of a couple
> >> >> > of chaps who had tried to steal live 11kV cables could be removed.
> >> >>
> >> >> Is that really an emergency? You can't save the two guys.
> >> >
> >> > Maybe if it interrupted the power supply in the area?
> >>
> >> Reset the breaker, shove the dead body off with a big stick first if necessary.
> >>
> >> > Or
> >> > if members of the public might be upset seeing two dead
> >> > bodies?
> >>
> >> That's not an emergency.
> >
> > Oh yes it is, if they are middle-class parents who own shares
> > in the energy company.
>
> That's a very unlikely scenario.

Who do you think they sell their shares to?

[F Murtz]

Jeff wrote:
> On 31/07/2016 15:57, James Wilkinson wrote:

>> On Sun, 31 Jul 2016 15:48:34 +0100, Jeff <je...@ukra.com> wrote:
>>
>>> On 31/07/2016 14:54, James Wilkinson wrote:
>>>> There's a substation near here with a short access driveway to it (room
>>>> for one car). I often see a car parked in it. Is this illegal? Would
>>>> the police tow it if I informed them? Or would they attempt to contact
>>>> the owner at the registered address? What trouble would he get into?
>>>
>>> As it is almost certainly private property it would be a trespass, but
>>> the police would not be interested or have any power to do anything.
>>
>> Wouldn't it be the same as parking in front of someone's drive and
>> blocking them in? He's restricting access to the substation. If you
>> called the police because someone had boxed you in, they would tow the
>> car to allow you out of your drive wouldn't they?
>>
>

> They might if parked on the public highway but this is a different
> situation. it is like someone parking on your drive and blocking your
> garage.
>

> Jeff
No it is worse than that,if there is an emergency he may be the cause of
someones death

[Nightjar]

On 01-Aug-16 10:38 PM, James Wilkinson wrote:
> On Mon, 01 Aug 2016 19:22:13 +0100, Nightjar <c...@bignell.me.uk> wrote:

...

>> However, when I worked for an Electricity Board, one emergency involved
>> making the whole substation area safe, so that the remains of a couple
>> of chaps who had tried to steal live 11kV cables could be removed.
>
> Is that really an emergency? You can't save the two guys.

A large area had been blacked out and the power couldn't be reconnected
until the bodies had been removed.


--
--

Colin Bignell

[James Wilkinson]

It wouldn't upset me if I had shares in them. So two stupid idiots killed themselves, I don't care.

--
Five out of four Americans have trouble with fractions.

[James Wilkinson]

Can't you just lever them off with a plank of wood?

--
Arriving home unexpectedly early from a business trip, the tired executive was shocked to discover his wife in bed with his next door neighbour.
"Since you are in bed with my wife," the furious man shouted, "I'm going over to sleep with yours!"
"Go right ahead," was the reply. "The rest will do you good."

[GB]

On 02-Aug-16 1:12 PM, James Wilkinson wrote:
> On Tue, 02 Aug 2016 10:02:38 +0100, Nightjar <c...@bignell.me.uk> wrote:
>
>> On 01-Aug-16 10:38 PM, James Wilkinson wrote:
>>> On Mon, 01 Aug 2016 19:22:13 +0100, Nightjar <c...@bignell.me.uk> wrote:
>> ...
>>>> However, when I worked for an Electricity Board, one emergency involved
>>>> making the whole substation area safe, so that the remains of a couple
>>>> of chaps who had tried to steal live 11kV cables could be removed.
>>>
>>> Is that really an emergency? You can't save the two guys.
>>
>> A large area had been blacked out and the power couldn't be reconnected
>> until the bodies had been removed.
>
> Can't you just lever them off with a plank of wood?
>

I can't quite believe that I am replying to this inanity, but here goes.

It would be necessary to check whether the 2 guys were actually dead. Of
course they'll turn the electricity off. Don't be such a ninny.

[James Wilkinson]

You can check that later, the most important thing is to remove them from the current. Levering them off is the quickest way.

--
U2's on-tour sound system weighs 30 tons.

[GB]

But not the safest for the people doing the levering.

[James Wilkinson]

Dry wood doesn't conduct.

--
Hard work pays off in the future. Laziness pays off now.

[Mr Pounder Esquire]

Why have lowered yourself in feeding the troll Hucker?
I've always thought that you had more brain cells.

[James Wilkinson]

PKB. Twice.

--
Paper clips are the larval stage of coat hangers.

[Fredxxx]

There is no such thing as dry wood.

It's also made of carbon, it conducts and chars very nicely for form a
very low resistance path.

Making suggestions like this, you don't come across as being very bright.

[Mr Pounder Esquire]

52457025
Dark days are coming your way Hucker.
Best you top yourself.

[James Wilkinson]

Dunno where you got that from, but you could only have obtained it illegally. What now, do I post your wife's bra size?

--
An ostrich’s eye is bigger than its brain.

[James Wilkinson]

On second thoughts, that number can be obtained by anyone from their website. So what's your point?

--
Nagry: the state of emotion a woman is in when yelling at her husband

[James Wilkinson]

Actually wood has quite a high resistance. Unless you're stupid enough to soak it first.
https://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity#Resistivity_and_conductivity_of_various_materials

--
Never raise your hands to your kids.
It leaves your groin unprotected.

[James Wilkinson]

On Tue, 02 Aug 2016 21:07:15 +0100, Fredxxx <fre...@nospam.com> wrote:

[AndyW]

You really do not have a clue about electricity do you?

There is no such thing as a universal insulator. What we call an
insulator is actually a material that has a dielectric breakdown point
above that of the voltage in the particular case.

A sheet of paper will save you from a 12V battery but I would never use
it to save me from mains voltage. Rubber gloves will work from domestic
or industrial mains but use it to grip a car HT lead and you could get a
shock.

Dry wood (which is never dry as it is a naturally hygroscopic material
and will draw moisture from the air) will probably be safe from domestic
and usually industrial mains but a smallish substation will have about
11,000Volts and a grid substation up to 400,000Volts. That is enough to
arc/flash through damp air in the right circumstances so it sees wood
and a person as a nice path to earth.

I suspect that you are applying old fashioned first aid electrocution
rules to an industrial scale.
Asking someone to use 'dry wood' in a damp British autumn (or even a
summer) on a substation is asking for a death.

Shutdown. Make safe. Then pull the smoking corpses away. It is less to
do with saving the barbecue charcoal that use to be people and more to
do with saving the equipment from permanent damage. A meat sack is a
short circuit to earth than could overload and blow a unit.

Andy

[AndyW]

On 02/08/2016 22:43, James Wilkinson wrote:

> Actually wood has quite a high resistance. Unless you're stupid enough
> to soak it first.
> https://en.wikipedia.org/wiki/Electrical_resistivity_and_conductivity#Resistivity_and_conductivity_of_various_materials

Try reading your own link:

"Wood is widely regarded as an extremely good insulator, but its
resistivity is sensitively dependent on moisture content, with damp wood
being a factor of at least 1010 worse insulator than oven-dry.[33] In
any case, a sufficiently high voltage – such as that in lightning
strikes or some high-tension powerlines** – can lead to insulation
breakdown and electrocution risk even with apparently dry wood."

** like.... say you would find in a substation?

Andy

[GB]

On 02-Aug-16 9:50 PM, Mr Pounder Esquire wrote:

> ********

> Dark days are coming your way Hucker.

If that's Hucker's phone number, you're taking this a bit too far. It
could amount to harassment.

If it's his waste measurement, that's fine.

[GB]

I mean waist.

[AndyW]

I was wondering just how much waste he produced.
52 million... cubic meters, liters...?

Andy

[James Wilkinson]

On Wed, 03 Aug 2016 10:07:41 +0100, GB <NOTso...@microsoft.com> wrote:

> On 02-Aug-16 9:50 PM, Mr Pounder Esquire wrote:
>
>> ********
>> Dark days are coming your way Hucker.
>
> If that's Hucker's phone number,

It's an account number. He seems to think he can do something with it.

> you're taking this a bit too far. It
> could amount to harassment.
>
> If it's his waste measurement, that's fine.

Mr Pounder is a sad old man who has too much spare time since retirement. He's never had any hobbies and his wife spends all her time playing Angry Birds so he has nothing better to do than annoy everybody on newsgroups.

--
Why does the law society prohibit sex between lawyers and their clients?
To prevent clients from being billed twice for essentially the same service.

[Dan S. MacAbre]

Nightjar wrote:
> On 01-Aug-16 11:18 AM, James Wilkinson wrote:
>> On Mon, 01 Aug 2016 09:33:17 +0100, Nightjar <c...@bignell.me.uk> wrote:

>>
>>> On 31-Jul-16 2:54 PM, James Wilkinson wrote:
>>>> There's a substation near here with a short access driveway to it (room
>>>> for one car). I often see a car parked in it. Is this illegal? Would
>>>> the police tow it if I informed them? Or would they attempt to contact
>>>> the owner at the registered address? What trouble would he get into?
>>>

>>> The chances are that the land the access road lies on is part of the
>>> adjacent property and the electricity supply company has access rights
>>> over it. Otherwise I would expect it to be fenced and gated right up to
>>> the road, as many are. Where the electricity supply company has access
>>> rights over land, they will, except in the case of an emergency,
>>> normally be required to give advance notice of when they will need
>>> access and the land owner can use the land at other times.

>>
>> Oh. I take it any emergency access is probably just needing a bloke to
>> be able to open the fence and turn off a breaker.
>
> More likely to turn one on that has tripped and cannot be reset remotely.
>

> However, when I worked for an Electricity Board, one emergency involved
> making the whole substation area safe, so that the remains of a couple
> of chaps who had tried to steal live 11kV cables could be removed.
>

Some photos here, for the non-squeamish.

https://ashlianne.wordpress.com/2010/03/21/dallas-copper-bandits/

[James Wilkinson]

Damp wood has a resistivity of 1x10^3 to 1x10^4 ohm metres.
Oven dried wood has a resistivity of 1x10^14 to 1x10^16 ohm metres.

Lets assume there's a plank of wood for this purpose kept in the back of the electrician's van. It won't be damp, but it won't be oven dried either. Let's say it has a resistivity of 1x10^9 ohm metres. If it's a 2x4, and you hold it about a metre from the HV, R = resistivity x length/x-sectional area = 1x10^9 x 1/0.00516128 = 194,000 Mohms. Even with the whole 11kV across it, you'd get a current of 0.056 microamps. That won't even tickle.

Even the dampest wood at 1x10^4 ohm metres would be 2MOhms. The current would be 5.6mA. AFAIK 30mA is deemed to be enough to stop your heart.

Going back to the being prepared and having wood in the van. If he's going to have something for pushing stuff off, he could have something even less conductive. So no need to turn anything off.

--
Marriage changes passion. Suddenly you're in bed with a relative.

[James Wilkinson]

Cool!

Oh look, there's a suggestion to hit them with a stick. Like I said earlier.

--
Murphy says to Paddy, "What ya talkin into an envelope for?" "I'm sending a voicemail ya thick sod!"

[AndyW]

I know about resistance, I have a degree in Electrical and electronic
engineering and I work on marine engines at 11KV including power
generation, distribution and client systems.

Ohm's law does not apply in these cases, this is about electromagnetics.
The mechanism that will kill you ignored Ohm's law, you basically git
hit by lightning lasting from under a second to however long it takes
them to shut off the power. You are trying to apply static equations to
dynamic situations, this is not about Ohms and V=IR this is Volt-Amps,
vectors, field equations and impedances.

It is not about resistance it is about electric field strength,
dielectric breakdown and arc flash.
It does not need actual physical contact to kill, if you get close
enough the increase in potential field strength can overcome the
dielectric strength and cause a flash. Basically you get hit by
lightning, usually it acts for a few cycles but you can get a persistent
arc like that created by an arc welder; once the arc has initiated it
can self-sustain by incrementally reducing the arc-path impedance though
its own plasma.

The bottom line is this.... if you go into a sub station with a plank of
wood then Ohm's law means nothing, you are nothing more than a big
reduction in dielectric strength carrying another reduction in
dielectric strength. Arc flash can occur from about 440V upwards and
some substations carry 11Kv up to about half a mega-volt. My 11KV
systems have a prohibited arc-flash range of a metre and that is inside
in a warm, dry and controlled environment. An outside substation
carrying over 11KV in damp conditions with rain, accumulated dirt,
clouds of insects (there is an interesting case of a substation near a
river arc-flash frying a cloud of mayfies) and wet ground this can
extend to several metres.

I suggest you study some Electromagnetics. I think that
"Electromagnetism and its Applications" by Bolton is still regarded as
the standard text.

Andy

[GB]

On 04-Aug-16 7:42 AM, AndyW wrote:
>
> The bottom line is this.... if you go into a sub station with a plank of
> wood then Ohm's law means nothing, you are nothing more than a big
> reduction in dielectric strength carrying another reduction in
> dielectric strength. Arc flash can occur from about 440V upwards and
> some substations carry 11Kv up to about half a mega-volt. My 11KV
> systems have a prohibited arc-flash range of a metre and that is inside
> in a warm, dry and controlled environment. An outside substation
> carrying over 11KV in damp conditions with rain, accumulated dirt,
> clouds of insects (there is an interesting case of a substation near a
> river arc-flash frying a cloud of mayfies) and wet ground this can
> extend to several metres.

I understand exactly the mechanism you are describing, but I am really
surprised at the numbers you are giving.

https://en.wikipedia.org/wiki/Dielectric_strength

This gives the dielectric strength of air as 3MV/m. This means (if I
have understood correctly) that you wouldn't expect 11Kv to arc over
until the gap got down to around 3.67mm.

That's of course in ideal conditions - dry air, no dust, etc. I can
certainly understand why you would create a safety zone of 1m, but if my
3.67mm calculation is correct 1m seems like quite a big safety margin.

Once the arc occurs, the ionisation would reduce the resistance, and
hence my initial reaction was surprise at your comment that the arc
often dies down after a few cycles. I suppose the ionised air heats up
and rises upwards, creating a longer path?

[AndyW]

On 04/08/2016 09:37, GB wrote:
> On 04-Aug-16 7:42 AM, AndyW wrote:
>>
>> The bottom line is this.... if you go into a sub station with a plank of
>> wood then Ohm's law means nothing, you are nothing more than a big
>> reduction in dielectric strength carrying another reduction in
>> dielectric strength. Arc flash can occur from about 440V upwards and
>> some substations carry 11Kv up to about half a mega-volt. My 11KV
>> systems have a prohibited arc-flash range of a metre and that is inside
>> in a warm, dry and controlled environment. An outside substation
>> carrying over 11KV in damp conditions with rain, accumulated dirt,
>> clouds of insects (there is an interesting case of a substation near a
>> river arc-flash frying a cloud of mayfies) and wet ground this can
>> extend to several metres.
>
> I understand exactly the mechanism you are describing, but I am really
> surprised at the numbers you are giving.
>
> https://en.wikipedia.org/wiki/Dielectric_strength
>
> This gives the dielectric strength of air as 3MV/m. This means (if I
> have understood correctly) that you wouldn't expect 11Kv to arc over
> until the gap got down to around 3.67mm.
>
> That's of course in ideal conditions - dry air, no dust, etc. I can
> certainly understand why you would create a safety zone of 1m, but if my
> 3.67mm calculation is correct 1m seems like quite a big safety margin.

You are almost certainly correct in your calculation but it is a perfect
static calculation in perfect circumstances and ignores surges,
atmospheric changes, effects of poor ships husbandry* etc that can cause
a flash.
* I was involved in the aftermath of one of these after an HVAC filter
was removed from a system and allowed crud and dust to build up causing
a flash in an air circuit breaker.

For a fixed conductor in good conditions (eg a cable or terminal) then
you *should* be safe at an inch or so.
For a moving conductor (eg a contactor or circuit breaker) when it moves
you can (but should not due to suppression) get an arc produced that
will usually arc between the terminals until it reaches a critical gap
and then it extinguishes.
If there is a good ground nearby or even as much as a long human hair
floating past that could provide a better path then air it can jump to
that. There are cases of flashes bursting out of cabinets to hit people
nearby.
In addition your static calculation does not take account of the surges
experienced when client equipment shuts down and the generators are
still dumping energy into the system. These surges are usually dumped to
massive resistor banks but there is a delay especially if the offload is
an emergency or failure and not planned and carefully controlled.

Also an arc flash will produce a blast of heat reaching into the tens
of thousands of degrees Celsius that produces an expanding plasma cloud
and lumps of burning metal even if the suppressions systems cut in. PPE
is required just to enter the compartment due to the risk of injury or
death due to secondary effects of the flash. You could actually survive
the electricity and be killed by the gas and metal.
Once the arc is created then it can expand to the arc flash limit which
could be tens of metres away.

> Once the arc occurs, the ionisation would reduce the resistance, and
> hence my initial reaction was surprise at your comment that the arc
> often dies down after a few cycles. I suppose the ionised air heats up
> and rises upwards, creating a longer path?

A lot of HV kit have arc detection and suppression systems that will
prevent it building but I did say "Basically you get hit by lightning,
usually it acts for a few cycles <where the suppression system cuts in>

but you can get a persistent arc like that created by an arc welder;
once the arc has initiated it can self-sustain by incrementally reducing

the arc-path impedance though its own plasma. <if it does not kick in> "
There are multiple cases in the InMarEST proceedings and MCA Guidance
Notes where suppression systems have failed resulting in arcflashes and
resulting death or sever injury.

My main thrust was that going into a substation with a piece of 'dry'
wood to knock away an ex-human charcoal statue is like looking for a gas
leak with a lighter.... you may get just away with it but if it goes
wrong at all it goes wrong big. It is an all or nothing thing really.
James was talking about actually hitting a live conductor which is just
asking for trouble 'dry' wood or not.
James's physics is fine for static ohm's law but what kills people in
these circumstances does not follow Ohm's Law.

I seem to have gone on a bit. Sorry about that.

Andy

[GB]

On 04-Aug-16 2:40 PM, AndyW wrote:

> I seem to have gone on a bit. Sorry about that.

Don't say that. It's really interesting how different practice is from
theory.

[James Wilkinson]

What about using an insulating huge rod of plastic?

--
"VAT is a simple tax..." -- Anthony Barber, Chancellor of the Exchequer on the introduction of VAT on April Fool's Day in 1973.

[GB]

On 04-Aug-16 5:40 PM, James Wilkinson wrote:

> What about using an insulating huge rod of plastic?
>

Please keep your dreams about your penis to yourself.

[James Wilkinson]

Why would someone dream about their OWN penis?

--
To make the train seat next to you remain empty, simply smile at anyone approaching it and pat the seat.

[GB]

On 04-Aug-16 6:18 PM, James Wilkinson wrote:
> On Thu, 04 Aug 2016 18:06:31 +0100, GB <NOTso...@microsoft.com> wrote:
>
>> On 04-Aug-16 5:40 PM, James Wilkinson wrote:
>>
>>> What about using an insulating huge rod of plastic?
>>>
>>
>> Please keep your dreams about your penis to yourself.
>
> Why would someone dream about their OWN penis?
>

Because nobody else will come near yours, perhaps.

[James Wilkinson]

And that would make me dream about it?

--
Sit on my lap, and we'll talk about the first thing that comes up.

[GB]

On 04-Aug-16 7:58 PM, James Wilkinson wrote:
> On Thu, 04 Aug 2016 19:46:46 +0100, GB <NOTso...@microsoft.com> wrote:
>
>> On 04-Aug-16 6:18 PM, James Wilkinson wrote:
>>> On Thu, 04 Aug 2016 18:06:31 +0100, GB <NOTso...@microsoft.com> wrote:
>>>
>>>> On 04-Aug-16 5:40 PM, James Wilkinson wrote:
>>>>
>>>>> What about using an insulating huge rod of plastic?
>>>>>
>>>>
>>>> Please keep your dreams about your penis to yourself.
>>>
>>> Why would someone dream about their OWN penis?
>>>
>> Because nobody else will come near yours, perhaps.
>
> And that would make me dream about it?
>

Apparently, yes.

[AndyW]

If you cannot extrapolate from the given information then it is not for
me to educate you.


Andy

[James Wilkinson]

Well they have insulators on pylons that work, there's no reason you can't have something that can be used to push animals or people off substations without having to shut the thing down.

--
"The problem with defending the purity of the English language is that English is about as pure as a cribhouse whore. We don't just borrow words. On occasion English has pursued other languages down alleyways to beat them unconscious and rifle their pockets for new vocabulary." -- James Nicoll, rasfw

[AndyW]

There are lots of reasons.

Why no go away and learn something about the subject and then come back
and debate it?
Start with some high school physics, then go on to some basic uni level
electotechnology then look at electromagnetic theory.
It is not for me or this NG to give you an education in HV physics.

Alternatively just take a walk into an 11KV substation with your 'dry
wood' and hit a terminal as you seem to think is a safe thing to do and
then come came and report your findings.... or not.

Andy