"Tim Watts" wrote in message
...
Roger Traviss wrote:

Then there's the rather creative method of theft intended to avoid
detection
which was employed recently (for obvious reasons I will not go into
details). Suffice to say the use of that method on the wrong cables
could result in a decidely non fail-safe situation.

Doesn't the absence of a signal indication where expected indicate "Stop"
or the most restricting indication possible?

That alone is fail safe.



In the dark, in the fog on a bend with lots of lines???

This is what can happen when a signal is unlit
http://www.railwaysarchive.co.uk/doc...ssocks1978.pdf

The train which followed the collided train also passed the unlit signal,
but stopped short of the collision.

Peter