Re: Head on in the Western district

[Eddie Oliver <eoliver@efs.mq.edu.au>]

Dave Malcolm wrote:
 
> In article <3841EBAB.D27C422E@ozemail.com.au> David Johnson <trainman@ozemail.com.au> writes:

> >Maurie Daly wrote:

> >> Anyone know how SRA handles unattended points on mainlines under train orders?
> 
> >Point Indicators.  A 4 square foot black square with a white line at 45 degrees
> >for
> >straight ahead, or horizontal for turnout.
> 
> Not Quite right. The're Main Line Indicators (MLIs) and are interlocked with
> the facing point lock and indicate if the points are set and locked for the
> main line, they do not indicate the way the points lie.

Hold hard. 

MLIs are the pseudo-signals provided at some locations to certify the
state of a sequence of points, level crossing status, or something other
than the position of just an individual set of points. They display red
if the points (or whatever) are not set for the main line route, or
pulsating white if the main line route is set (or in a few cases yellow
if the route is clear past the present MLI but there is a subsequent MLI
not cleared).

The point indicators display the status of individual points (or I think
there are a few cases where they may deal with two sets of points in
close proximity).

Eddie Oliver