It never ceases to amaze me how much effort people put in doing something wrong!
These optical sensors for the garage door are meant to be mounted down low (no more than 5 – 6 inches off the floor) on each side of the garage door to reverse the door if the beam is interrupted by kids, cats, dogs, etc.
However, the kids, cats, dogs, etc are going to have a hard
time interrupting the beam on these sensors, mounted on the ceiling of the garage behind the garage door opener