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Boltar · August 11th 03, 11:24 AM posted to uk.transport.london

are (Acrosticus) wrote in message ...
From: Michael Bell
Date: 08/08/2003 23:43 GMT Daylight Time

It has always seemed to me that the 750 volt 3rd rail is a bad
idea.

Too right! Massive amperages, high resistances, huge numbers of substations in
relation to the length of a line. It's an idea that's really past its sell by
date. If you want to electrify, do it properly with 25Kv at 50 Hertz in a wire
up on some sticks. Tinkering about with 750v DC is about as much good as
rearranging the deckchairs on the deck of the "Titanic".

OTOH hand , when was the last time that you heard of trains being stuck or
cancelled because the 3rd rail fell over? There doesn't seem to be a winter
that goes by without some AC line being screwed by snapped overhead wires.
Catenary is fragile and flakey and is a terrible design plus it looks bloody
awful too. The only place its really needed is street based tramways.

What is needed is some sort of mid voltage (maybe 3000-6000V) sturdy ground
based 3rd rail system which isn't as fragile as overhead wires but doesn't
have the power losses of standard 750V 3rd rail. I'm sure isn't beyond the wit
of man to devise it.

B2003