so the rays of the motion detector when placed correctly shoot mostly down. by turning it upside down the rays shoot mostly upward thus making a pet curtain (no rays) at a lower elevation but this doesnt seen to work when the cat jumps on the top of the couch.
in other words you can taylor the rays of the motion detector by turning upside down and also raising the detector on the wall so that it doesnt detect motion 2-3 ft above the floor. it is trial by error
set the motion detector wait 2 min for it to adjust, put the system on test mode, then send the dog out to see if it detects it if it does raise it up on the wall.
but have to then make sure it still detects a human walking./