Re: New questions for rail experts

["Dave Proctor" <daproc@spambait.ozemail.com.au>]

"Greg Cantori" <greg@mpx.com.au> wrote in message
392a7311$0$2628@news01.syd.optusnet.com.au">news:392a7311$0$2628@news01.syd.optusnet.com.au...
> 1. On each platform there is a blue light called the "guards indicator".
>    What is its purpose, and why does it turn on and off?

At some stations, the guard cannot see when the signal is set for the train
to proceed, so this indicator tells the guard when the train can leave. It
is based SOLELY on the signals, not on any time basis.

> 2. On the tracks every 50 metres or so is a metal switch-thing that
>    is up after a train has passed, then flips down when the train is
>    a safe distance ahead. Presuming this causes a following train to
>    brake if it goes over it while up, why doesn't the train that
>    set it up in the first place get caught when its last carraiges
>    go over it? (unless of course it's the last carriage that sets it up!)

I believe these are train stops. Don't know about the every 50 metres part
though.

They are normally adjacent to signals, although they can be situated in
other areas (a lot closer than 50 metres thou gh).

If you have a look at the front of Sydney and Melbourne trains, just below
the drivers cab is a lever, known as a trip. This is positioned at such a
height as to make contact with the train stop, located next to signals (and
elsewhere, as noted).

When the signal is safe to pass, the train stop will lower, so the trip will
not make contact with it. The train will pass without impediment. IF,
however, the signal is at stop (with one exception) the train stop will stay
up, and the trip will make contact, triggering an emergency brake
application.

The exception is low speed signals, where there is some sort of speed
detection (I don't understand how it works). Basically, if the train gets
its average speed down below a certain level, the trip will drop, otherwise
it will stay up and stop the train.

> 3. Why don't guards shut up and let passengers relax/sleep? Do we
>    really need to be constantly told where the train that we deliberately
>    caught is going?  Inter-urban services are usually quite considerate
>    in this respect, but city trips can be a barrage of repititious
>    chatter, and is totally unneccesary.

Ever travelled in an unfamiliar city? Or on a mode of transport you don't
normally use? Or on a train with a different stopping pattern than the one
you normally use?

Announcements serve a useful purpose for all except the regular travellers.
However, the irregular passengers are increasing.

> 4. What's a "V" set that people on this list always talk about?
>    (Another name for a Tangara, taken from the shape of the 4th and 5th
>     carriages in a set of 8 cars?)

The double deck interurbans, that go to Dapto, Lithgow and Newcastle.

Dave