Re: Signalling in Victoria

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

Christopher_Martin GORDON wrote:

> Ok, just a couple more questions about 2 position signalling.  The numbers on
> the signal posts are usually the lever number, and where there are many levers
> the first lever number is on the post.  Is this correct?  If so then in places
> like Sunbury the lever (switch) number has no relationship with the post
> number.

No it's not. 2 pos sigs are numbered in a sequence. 3 pos sigs are generally
numbered with the lowest lever working it.
Sunbury is 2 pos hence posts are numbered sequentially.

>
>
> Disc and dawf signals. Most sidings and wrong line moves have/had disc
> signals, if you have a colour light signal is it called a disc, or a two
> position dawf?

a dwarf signal, the number of aspects need not be referred to. It will be 2 pos in
a 2 pos area etc.

>
>
> 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. The Showgrounds signal is labelled siding because drivers are maybe confusing
it with the main line signal, they are identical in looks but mean quite different
things.

>
>
> Now three position signalling.  Where you have a signal that shows red/red,
> yellow/red & green/red it is three aspect signalling?

If the signal has an "A" arm and a "B" arm but not necessarily a "C" light it is a
3 pos signal. Notice I said A/B arm but C light. In Victoria the top two aspects
can be displayed by arms (Kensington/Newmarket etc) or lights (many places) but
the low speed signal has always been a light hence the term "C" light.

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

Yes. But it is still 3 pos signalling displaying 4 aspects. Confusing?

>
>
> 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?

Yes but it still referred to as a 3 pos home 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.

A signal that cleared from R/Y to Y/R would have had its overlap improved and it
would have little to do with the next signal except indicating that it is a stop.
Overlap improvement in most cases is where a signalman alters the road ahead not
the train moving further on. In the case of a train moving along the aspects would
be R/R, R/Y, Y/G, G/R. i.e. 4 aspects.

>
>
> 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 with train stops. (or trip arms)

>
>
> Transition from Two position signalling to three position, sometimes it is
> like Greensbourgh where there is a home to post X and then post X is a three
> position signal.

> Or like St Albans where you have a home signal, repeating, then a threeposition
> home.  I think the repeating signal is like a distant (but with ayellow
> marker).  Is that right?

There is no home in advance of the St. Albans repeater. On the up into St. Albans
you have a repeater leading onto an 3 pos automatic signal leading onto a 3 pos
home signal. The repeater displays Y/Y or G/Y only. There were repeaters at 2 pos
stations which displayed the same indications but this time the repeater only gave
advance warning of the distant signal. Ballan had an up repeater which had nothing
to do with the CTC because it was there before the CTC. It repeated the
mechanically operated distant which couldn't be moved any further out without
providing a motor. G/Y on the repeater meant that the distant was off which of
course meant that all the signals at Ballan were off and the train had (as they
say in New South Wales) "the full road".

>

>
> What colour are the arms on a semaphore repeating signal?  I know of only one
> semaphore repeating that was at Maldon Junction any I have no idea what colour
> the arms were.  The top arm was fixed at yellow, and the bottom yellow or
> green.

You mean the up repeater from the Maldon line which was the only 2 arm repeater.
The up repeater from the Maryborough line was a single arm repeater. The colour of
the arms was yellow in later years but it is believed that they were red when
first installed but to date I have not seen any documentation to support this.

>
>
> Well that's all I need to know for now (until I am totally confused again)

You are quite welcome to email me directly if you wish any further information. I
am a member of the Signalling Record Society which is a group of people whose
specialty is railway signalling.

>
>
> Regards,
>
> --
> Chris Gordon
> http://www.ecr.mu.oz.au/~cmgord