Re: Concord West Derailment

[krel4203@netconnect.com.au (Krel )]

>> EG in Vic automatic signals that can only display three indications
>> (clear, warning and stop) have a fixed lower red light.
>
>Incorrect. All speed signalling aspects are available on an Automatic Signal in
>Victoria.
>It is very possible to get Medium speed aspects.
>
Please read again. I said "Vic automatic signals that can only display
three indications". IE Some autos display the whole range, some only
display three indications. Not every auto can display every possible
aspect. As a general rule autos out in the section only display three
aspects (G/R, Y/R, R/R.) Autos approaching loops, etc can show medium
speed and reduce to medium speed aspects. Those autos that can only
display three indications have a fixed lower red light.

I was asking why you need two lights to do what one can do; signal
clear, caution or stop?

>> and why red?
>
>Red is used as one of the colors for Victorian speed signalling. In some areas, the
>top aspect is a fixed red, showing only medium speed aspects on that signal.
>
Granted; where an auto is used for Medium speed aspects it makes sense
to use an upper red light. But where they don't it doesn't.

>> If the top light is obscured or out the lower red light tells you nothing.
>
>Route knowledge should tell you when you are in a 3 position speed signalling area.
>
Yes, But you still have no idea what the signal is displaying. In NSW
the lower red light is only illuminated if the top light is red or
out. If the top light is yellow or green there is no lower red light -
less risk of confusion.

>If the top light is extinguished, then you would assume the signal to be at the most
>restrictive aspect ie: RED

same everywhere.

>the red light on the bottom tells you that there is a signal there and it is
>defective.
>
That is my point. If the signal is one that only shows G/R, Y/R or
R/R, the bottom light being out should not stop trains. Green over
black on this signal is obviously clear but the rules state that I
must stop, contact control and then proceed with extreme caution
expecting to find a broken rail, defective points or another train.
All this after seeing a top Green!!! Sounds like a waste of time,
brakes and fuel to me but rules is rules.

Cheers

Krel

Just another eccentric crank.