Em 18/07/2013 11:34, Ruben J=F6nsson escreveu:
>> In tunnels near villages, people travel through them. So when the lights=
=20
>> brighten up, they will now that a train is coming and have to move out=20
>> of the tunnel.
>>
>> The lighting are solar based hence they need to be dimmed to conserve po=
wer.
>>
>>
> Who is this for? The railroad company that wants to dim the lights to con=
serve=20
> power or is it a warning system for the people in the villages?
>
> Why not use the same system (whatever that is) as is used for the lights =
and=20
> bars on railroad crossings? Then you get the same safety levels as for a=
=20
> crossing. It too must sense a train from about 2km away, or?
>
> /Ruben


Indeed, laying 2km of cable may be the easiest and most reliable solution.
The OP said the terrain is rough, but of course it is smoothed and
bulldozed along the tracks, so it should be easy to lay the cable along
them, then use the most suitable sensor to detect the train on the spot,
not far away.

Perhaps not the least expensive solution but should be the safest.

Isaac

--=20
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