London Banter - View Single Post

Steve Fitzgerald · September 12th 10, 02:34 PM posted to uk.transport.london

In message ,
writes

I look forward to seeing the full report if the RAIB to find out
what lessons can be learned for future safety.

Thanks for correcting my terminology, Steve. I was exactly meaning to
exclude repeaters which don't have train stops. Does that include fog
repeaters, BTW?

Yes it does. There are no fog repeaters with red aspects (after all,
they wouldn't be a repeater then would they?)

What seems to be rare on LU is three aspect signals. There used to be one
at the entrance to the Southbound platform at East Putney but that might
be BR practice.

On LU They are generally speed controlled signals and work in a subtly
different way although they are still stop signals and have a train
stop.

If they show green, there is a clear route set and no speed checking is
in place.

If they show red, speed checking is in place and the signal will show a
yellow aspect and the train stop will drop when the train's speed has
been proved below a set figure.

They are mainly used to protect reduced overlaps on signals to ensure a
train doesn't go thundering through an area with the potential risk of
collision.

All speed control signals seem to work in slightly different ways
depending on the local requirements and road learning includes these
nuances.

Of course where we share with BR then their signalling practices are in
force.
--
Steve Fitzgerald has now left the building.
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