Re: Signalling in Victoria

[David Langley <del@ancc.com.au>]

Tony Gatt wrote:

> Christopher_Martin GORDON wrote:
>
> > Eltham has two homes (on for each road) and a dawf/disc for the sidings, this
> > is a little like the Showgrounds (ie it has a 'siding' sign and it normally
> > off, but shows yellow for moves into the sidings), I spose in the days of
> > semaphore signals this would have been a disc.
>
> yes, it was.. two arms and a disc. On the down Home arrival, the left arm applied
> for the platform road #1, the right arm applied to the back platform, the disc was
> for the sidings.
>
> In some cases like Eltham there would normally be more than one disc where the
> points for the siding are controlled from the frame. thus, if there were 3 sidings
> then there would be 3 discs.

Not necessarily. Many stations had one disc leading to a number of sidings.

>
>
> Castlemaine Post 10 is a good example of this.
> http://homepages.tig.com.au/~baulko/signals/castlemaine_post_10.jpg
>
> > Now three position signalling.  Where you have a signal that shows red/red,
> > yellow/red & green/red it is three aspect signalling?
>
> Yes, 3 aspect Speed Signalling.

No 3 position signalling with 3 aspects.

>
>
> > Where you have red/red, red/yellow, yellow/green & green/red it is four aspect
> > signalling?
> >
>
> Correct again.

No 3 position signalling with 4 aspects.

>
>
> > Where you have say a junction and the signal shows red/red, yellow/red &
> > green/red for one route or red/red, red/yellow & red/green apart from the
> > being a home signal would you say the signal has 5 aspects?
>
> No, this is just speed signalling. In most circumstances, the Normal speed ( ?/r)
> would be shown for the "straight" line.

Victorian 3 position is all speed signalling.

>
>
> Any diverging line would be given the medium speed aspect. ( r/?).
>
> On your theory, a signal as stated with a low speed (r/r/y) would be a 6 aspect
> signal....
>
> > Signals the clear in the following order: red/red, red/yellow, yellow/red,
> > yellow/green, & green/red (I think that is right) it has the yellow/red aspect
> > because a full overlap is provided after the train has past some point, but
> > the next signal is still red/red.

We do not go any further than saying that it is 3 aspect or 4 aspect signalling. It is
immaterial how many aspects a particular home signal can display.

>

snip

>
>
> > All dawf signals are three position (in three position signalling area) but
> > some only show two aspects.  The signals at either end of the centre road of
> > Clifton Hill are three aspect with trip levers.  Are these dawfs, or home
> > signals, or something else?
>
> Dwarf signals:
>
> Red= stop
> Yellow = proceed at low speed, expect to find line obstructed / occupied.
> Green = proceed at low speed, line clear to next fixed signal.

Box Hill, Camberwell & Dandenong, to name just three, had dwarf signals which
displayed all three aspects.

>
>
> These signals have been in use at some time at other locations.
> The beauty is at the Down end of Somerton Loop from 3 & 4 roads, on the Std
> Gauge...
> It displays yellow for moves to Blue Circle cement sidings (controlled from
> Somerton Box) and
> Green for moves to the main line (controlled from Centrol).

The rule about these signals was that although you proceeded at low speed onto the
main line with a green aspect the train could accelerate to line (or train) speed when
the train was clear of the turnouts for which the signal was provided.

>
>
> I do think the "local" rules applying to these types of signals are based on the
> needs of the location.

See above.

DEL.