Re: Double Colour Light Signalling

[Tony G <kevytony@hotkey.net.au>]

David Bromage wrote:
*snip David Johnsons article*
> 
> Yet Melbourne can't run high density suburban trains at much more than
> 80km/h. There are very few sections where suburban EMUs are allowed 100 or
> 115km/h. The problem there is usually only one warning between "clear
> normal speed" and "stop".
> 
> G    Y    R
>  R    R    R
> -------------->
> 
> Most trains would have to slow from 80km/h to stop within the length of
> the block.
> 
> By adding some medium speed aspects as standard, speeds could be
> increased. Underneath are the probably speeds when passing each signal
> post.
> 
> G    Y    Y    R    R
>  R    R    G    Y    R
> ------------------------->
> 115  115  80   40   0
> 
> Cheers
> David

The aspects given above could not be provided by Victorian Signalling,
as the Y/R aspect would indicate that the next signal would be at STOP.

Correct sequencing (as used to Werribee) would be 4 aspect:
G	Y	R	R			
 R	 G	 Y	 R
--------------------------->

This only other possible addition would be the inclusion of a R/G after
the Reduce to medium speed (Y/G) which would increase the section by
one, (but still restrict the train to Medium speed)

Express trains from Newport to Werribee every 10 mins at 115km/h and one
stopping every 30 mins are run during the Avalon airshow using these
aspects. The only problems they encounter is Interlocking timeouts at
Werribee, and the occasional Overhead problems.

Besides, I dont think that it is our signalling that restricts the
speed, the only place I know where 115km/h exists is Newport to
Werribee, and it's the straightest line I know.
-- 
                    
Thanks 
Tony G.