London Banter

London Banter (https://www.londonbanter.co.uk/forum.php)
-   London Transport (https://www.londonbanter.co.uk/london-transport/)
-   -   Shielding 750 volt 3rd rail ? (https://www.londonbanter.co.uk/london-transport/513-shielding-750-volt-3rd-rail.html)

Arthur Figgis August 13th 03 09:13 PM

Shielding 750 volt 3rd rail ?
 
As 12 Aug 2003 01:19:59 -0700 appeared fresh and rosy-fingered,
(Boltar) wrote:

[third rail]

Thats only because currently (no pun intended) high speed lines use overhead
because they use high voltage, they're not intrinsically required like they
are on a tramway (to keep the electricity well out of the way of people and
vehicles).


FWIW, you don't have to have overhead lines for electric trams -
London had its conduit, and various places have had stud contact,
including parts of the brand new tramway in Bordeaux.

If a high power 3rd rail design could be devised (which I'm sure
would look substaintially different to "traditional" 3rd rail) then there is
no reason they couldn't use that and perhaps it might have avoided the problem
that the Eurostar had last year where freezing sea spray got onto the overhead
lines and stopped all the trains.


There is the problem of picking up the power at high speeds. Once you
start getting over 160km/h-ish the collector shoes can bounce around
too much. I suppose you could try some sort of pantograph running on a
low level wire, but I'm not sure that would achieve anything.

I can't help thinking if third rail was such a good idea someone else
would have installed it by now (add the Berlin and Hamburg S-bahns to
my list in the other post. They are metro-like, but pretty extensive.)

Why re-invent the wheel, and introduce an incompatible new system at
huge expense? Internationally 25kV 50 Hz is effectively standard
nowadays, the equipment is available off the shelf (and once we shoot
all the Daily Mail readers, sorry, I mean sort out the important
political issues, we might even be able to get standard foreign trains
running through to Britain on it).

--
Arthur Figgis

Andrew August 13th 03 10:16 PM

Shielding 750 volt 3rd rail ?
 
On the subject of conductor rail on the same side of platforms, its no
different really to people climbing on station roofs and coming into
contact with the OHLE,



except people shouldn't be climbing on the roof (by people I'm assuming you
mean passengers, correct me if I'm wrong). People shouldn't be trespassing
on railway lines, but passengers do have a legitimate reason to be on
platforms, and can accidentally slip, be pushed/bumped into etc, and fall
onto the track. I have actually seen this happen once, although thankfully
at a non electrified location without any trains in the area.

Andrew



Boltar August 14th 03 08:23 AM

Shielding 750 volt 3rd rail ?
 
] (Arthur Figgis) wrote in message ...
Why re-invent the wheel, and introduce an incompatible new system at
huge expense? Internationally 25kV 50 Hz is effectively standard
nowadays, the equipment is available off the shelf (and once we shoot
all the Daily Mail readers, sorry, I mean sort out the important
political issues, we might even be able to get standard foreign trains
running through to Britain on it).


They'll only be able to run on the CTRL, they'd be too big for other lines.
I can't understand why we have such a restricted loading gauge in this
country, I mean we had broad gauge on the GWR for heavens sake, surely the
loading gauge of that line if nothing else must have been built big enough for
european trains?

B2003

Richard J. August 14th 03 08:43 AM

Shielding 750 volt 3rd rail ?
 
Boltar wrote:
] (Arthur Figgis) wrote in message
...
Why re-invent the wheel, and introduce an incompatible new system at
huge expense? Internationally 25kV 50 Hz is effectively standard
nowadays, the equipment is available off the shelf (and once we shoot
all the Daily Mail readers, sorry, I mean sort out the important
political issues, we might even be able to get standard foreign
trains running through to Britain on it).


They'll only be able to run on the CTRL, they'd be too big for other
lines. I can't understand why we have such a restricted loading gauge
in this country, I mean we had broad gauge on the GWR for heavens sake,
surely the loading gauge of that line if nothing else must have been
built big enough for european trains?


Perhaps the height restriction is less? Also, when the main line through
Ealing and Southall was quadrupled in the 1870's, the new tracks were
standard gauge only. I guess that many changes to layouts since then have
eliminated any capability of running wider trains.
--
Richard J.
(to e-mail me, swap uk and yon in address)


Steve Dulieu August 14th 03 04:48 PM

Shielding 750 volt 3rd rail ?
 

"Mike Bristow" wrote in message
...
In article ,
Boltar wrote:
OTOH hand , when was the last time that you heard of trains being stuck

or
cancelled because the 3rd rail fell over?


Sometime around last year, around Bank. I can't remember the
details, but I think the central conductor rail "fell over", rather
than the outer one.

(OK: so it was trains being stuck/delayed/canceled because the 4th
rail fell over, rather then the 3rd. And it was a rather unusual
incident.)


Happened to the pozzie at Wood Green about 7 years ago, IIRC the LUL jargon
for such an incident is "Turned Juice Rail"
--
Cheers, Steve.
If The Good Lord had meant for us to be fiscally prudent, He would not have
given us the platinum credit card...
Change colour to PC Plod's lights to reply.



Steve Fitzgerald August 14th 03 05:12 PM

Shielding 750 volt 3rd rail ?
 
In message , Arthur Figgis
] writes
FWIW, you don't have to have overhead lines for electric trams - London
had its conduit, and various places have had stud contact, including
parts of the brand new tramway in Bordeaux.


In fairness though, The Bordeaux system isn't open yet and the stud
contact hasn't been proved to work successfully.
--
Steve Fitzgerald has now left the building.
You will find him in London's Docklands, E16, UK
(please use the reply to address for email)

Clive D. W. Feather August 14th 03 07:29 PM

Shielding 750 volt 3rd rail ?
 
In article , Matthew
Malthouse writes
} British Rail, very seriously underinvesting,
} Nowhere near true.
} Read Roger Ford's column in the current (August) Modern Railways.
The gist?


A detailed analysis of this canard. Basically, BR invested lots.

The perception as long as I can remember has been that railways have
suffered from lack of funds.


Yes, as in there's a lot of improvements that could have been done with
more money. But, unlike Railtrack, BR at least invested enough to keep
the network stable.

--
Clive D.W. Feather, writing for himself | Home:
Tel: +44 20 8371 1138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Written on my laptop; please observe the Reply-To address

Clive D. W. Feather August 14th 03 07:31 PM

Shielding 750 volt 3rd rail ?
 
In article , Mike Bristow
writes
OTOH hand , when was the last time that you heard of trains being stuck or
cancelled because the 3rd rail fell over?

Sometime around last year, around Bank. I can't remember the
details, but I think the central conductor rail "fell over", rather
than the outer one.


I've seen various reports at various times along the lines of "65
positive shoes found just outside X station because of a displaced
current rail". You even get the really nasty case where the displaced
rail displaces a shoe, which then displaces another piece of current
rail elsewhere, which ....

--
Clive D.W. Feather, writing for himself | Home:
Tel: +44 20 8371 1138 (work) | Web: http://www.davros.org
Fax: +44 870 051 9937 | Work:
Written on my laptop; please observe the Reply-To address

Matthew Malthouse August 15th 03 01:24 PM

Shielding 750 volt 3rd rail ?
 
On Thu, 14 Aug 2003 20:29:36 +0100 Clive D. W. Feather wrote:
} In article , Matthew
} Malthouse writes
} } British Rail, very seriously underinvesting,
} } Nowhere near true.
} } Read Roger Ford's column in the current (August) Modern Railways.
} The gist?
}
} A detailed analysis of this canard. Basically, BR invested lots.
}
} The perception as long as I can remember has been that railways have
} suffered from lack of funds.
}
} Yes, as in there's a lot of improvements that could have been done with
} more money. But, unlike Railtrack, BR at least invested enough to keep
} the network stable.

Fine, I'll go with that. ;-)

Come back BR! All is forgiven!

Matthew
--
Il est important d'être un homme ou une femme en colère; le jour où nous
quitte la colère, ou le désir, c'est cuit. - Barbara

http://www.calmeilles.co.uk/

Christine August 18th 03 06:46 AM

Shielding 750 volt 3rd rail ?
 
Displaced Conductor rails do happen, but not as often as damaged
overhead wires. And it doesn't take as long to repair.

C



On Wed, 13 Aug 2003 07:07:29 +0000 (UTC), Mike Bristow
wrote:

In article ,
Boltar wrote:
OTOH hand , when was the last time that you heard of trains being stuck or
cancelled because the 3rd rail fell over?


Sometime around last year, around Bank. I can't remember the
details, but I think the central conductor rail "fell over", rather
than the outer one.

(OK: so it was trains being stuck/delayed/canceled because the 4th
rail fell over, rather then the 3rd. And it was a rather unusual
incident.)



Life without sex just isn't life.
Make love not war!


All times are GMT. The time now is 04:28 PM.

Powered by vBulletin®
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2006 LondonBanter.co.uk