its one of them jobs im afraid
there is no chance of getting a cable to the other side
a pir system might work if i can find a sensor wich will not pick up a large dog or false alarm on badgers or foxes like in the past
do you have any thing in mind
can any body advise i need a sensor to cover a gateway to either make or break a contact when somthing or some one breaks the beam
the problem is its a 30m gap and i can only get a cable to one side so it has to be reflective or single beam i can get plenty that do 10 meters but cant find any the do 30meters and fed from one side only
does any one have any idea makes model
cheers nick