Re: Australian rail network notation

[billboltonREMOVE-TO-EMAIL@computer.org (Bill Bolton)]

David Johnson <trainman@ozemail.com.au> wrote:

> However, just to confuse things, the signals on the City Outer are
> all numbered with odd numbers, and the signals on the City Inner are all numbered
> wth even numbers.  This indicates to me that the entire City Outer line from
> Central all the way back to Central is the down line, while the City Inner is the
> up line.

A signalling electrician told me about 25 years ago that this came
about in the mid 1950s when they were linking up the two disconnected
ends of the Circle.  Previously both stubs of the City Railway had
been treated as "Up and Down" as far as signalling numbering went but
when it came time to link them a standard had to be adopted.  As the
Circle and North Shore trains share the route alignment between
Central and Wynyard, the signal electricians needed a consistent way
of identifying all the signals on that section (which in some cases
are virtually side by side on their respective routes), so the signal
numbering for the whole Circle was changed to the present scheme.

Cheers,

Bill
  
Bill Bolton
Sydney, Australia