ECN Forum Forums General Topics of the Trade Non-US Electrical Systems & Trades U.K. Electric rail

Just a few quick shots of the typical overhead electrification used on some U.K. rail lines.



The single-legged pantograph is common here:


Feeder to this section. Notice the rod-operated isolator switch:

Paul,
What sort of voltage are we talking about,
here?.
Are we talking low voltage DC, or High
Voltage DC, or an AC supply?.
Also, how does the Pantograph make contact,
with the overhead wires, is this automated
from the Drivers cab?.

These lines use 25 kV AC at 50 Hz. I think compressed air is used to raise and lower the pantograph. In the UK, only the Eurostar passenger trains between London and Paris/Brussels via the Channel Tunnel raise and lower the pantograph in motion. This action occurs at the UK side of the tunnel where the traction supply changes from the overhead 25 kV AC to the third rail 750 V DC used between the tunnel mouth and London Waterloo. When the new Channel Tunnel Rail Link is fully commisioned in a few years time, the high voltage overhead will continue all the way into London (St Pancras).

The shoes that contact the third rail (which is situated on the outside of the running rails) are also raised and lowered as required on the Eurostars. This is because lineside equipment in France (point {switch} motors I think) would be fouled by the lowered shoes. At the French end of the tunnel, there is a simple safety device designed to protect their point motors. A large concrete block is posisiond in such a way as to physically and traumatically remove any contact shoe left lowered.

This may sound a bit dramatic but in the UK in the 1970's a fatal rail accident was caused by a battery cover on a locomotive being left open. This struck a point motor and caused the blades to move under the train. The train overturned with tragic consequences.

Interesting details Hutch -- Thanks. I've ridden through the Channel Tunnel and have to say that it's a wonderful piece of engineering.

Thanks for that explanation,Hutch.
Since you posted your reply, there was an
incident in Wellington, our capital city,
where a couple of kids were "train-surfing"
and fell between the rods of the panto-graph, killing and burning them instantly.
I found out, that the trains in Wellington
use a system of 33kV AC 50Hz.
There was a large investigation over this
and it found that the rail company was at
fault, for "allowing non-paying passengers
to ride the train", you are probably as
confused as what I am.

I'm afraid that blaming someone else for somebody's stupidity seems to be a rapidly growing attitude throughout the English-speaking world.

Still train-related, I remember reading recently about some guy who tried to commit suicide by jumping in front of a subway train in NYC. He survived, but his lawyers then tried to sue the New York City Transit Authority for his injuries, saying that they hadn't done enough to make him aware of the dangers of jumping in front of a train!

What next? Maybe signs above the track, something like "Danger: Jumping in front of trains may be hazardous to your health." ???

Re your "train surfing" incident, apparently there was a similar craze on the Underground (subway) in London a few years ago. The idiots would hang on to the grab handles between cars as the train sped out of the station and play a game of chicken as who would be the last to jump off before the train plunged into the tunnel.

I know there have also been several incidents of members of grafitti gangs in London either being hit by a train while going about their vandalism or tripping in the dark and getting electrocuted on the tracks.

Two words: Darwin Award.




[This message has been edited by pauluk (edited 09-14-2002).]

Paul, just a short note, last night a guy in Auckland, was train-surfing and fell over the panto-graph, he is now in Auckland hospital, in a drug induced coma, as he recieved burns to 90% of his body when he fell, maybe now, the authorities might do something, but I would not hold my breath.
A lot of pain for a few minutes fun, eh.

I'm assuming from this that your NZ "train surfers" are riding on the top of the cars. Right?

Yes, can't think why.