> > Are there a variety of ways to trigger level crossing lights and signals?
>
> What about those little yellow boxes in the middle of the tracks on
> Adelaide suburban lines? They appear to detect the train as it passes over
> them and turn the signals to red. How do they operate? Metal detectors like
> at traffic lights, perhaps?
Those little yellow boxes work with the later generation railcars' vigilance
system. As I understand it as the railcar passes over one of those, a beeper
is sounded in the cab. The driver must reset the vigilance alarm within a
certain time, otherwise the cars' brakes are applied. I stand corrected if
someone has more accurate information.
Cheers,
Peter.
-- This is not an opinion of the Pichi Richi Railway, just the personal comments of the author. E-mail: loco@prrps.com.au