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Old August 12th 03, 04:12 PM posted to uk.transport.london
Nathan Whitington Nathan Whitington is offline
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First recorded activity at LondonBanter: Jul 2003
Posts: 11
Default Shielding 750 volt 3rd rail ?

(Boltar) wrote in message . com...
] (Arthur Figgis) wrote in message ...
That says more about particular implementations than anything
intrinsic to overhead lines. The ECML wires were put up very cheaply,
as the only way the treasury would allow it to be electrified at all,
and so fall over. The WCML ones are much better built, and don't tend
to fall over.


They might not fall over on their own but if something hits them or falls on
them its a pretty major task to reinstate them. If a 3rd rail gets damaged
its a far simpler job to fix.


plus it looks bloody
awful too. The only place its really needed is street based tramways.


High speed lines?


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). 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.

B2003


However collecting the juice at high speeds is a problem....