"SAFETY BEAMS"
A.k.a. photo cells and electronic eyes
Sad but true, some people across the country have had the misfortune of a pet that got injured or squashed by a garage door. For some unknown reason pets like to lie under a moving door or they try to run in/out when the door is in motion. Kids also play in the garage and some times with the opener. No one needs to explain that garage door openers are not toys, but even children have gotten hurt. Garage doors have closed on cars, people and animals.
As of January 1, 1993 all residential garage door openers in the U.S.A. are required by federal law to be installed with infrared sensors (safety beams). It is illegal for any garage door company to install any opener without its safety beam. If you had an opener installed after Jan 93 and the safety beams are not installed, that company could be liable in the event of an accident. A post Jan. 93 opener won't work without its safety beam so some installers cheat by putting the eyes on the power head. If you have a pre Jan. 93 opener and it passes the "safety reverse" test, you’re a okay.
The photocells are 12-volt electronic eyes that look at each other from both sides of the opening. They should be mounted about 6" off the floor inside the opening. If anything passes through the invisible beam, when the garage door is in a down cycle, the opener will automatically reverse. This law was intended to make your garage door and opener a little safer when children and pets are running around. It is also intended to reduce the liability of the manufacturer, because of a sue happy America.
There is a down side to having safety beams. The little heat they emitted is like a tropical vacation spot for insects. Spiders like to web around that area and lay their eggs in the lens area. You might think to spray some repellants around that area. If dirt blows into the lens it can obstruct the beam. Your door will open but then it won't go down. You should try to keep the lenses clean. One of the eyes has a red or green light that either blinks or goes out when the eyes are not aligned. Your safety beams should have a little play so slight vibrations don't make your door reverse. Try to wiggle them slightly to see if the light blinks. Then adjust them slightly so the light won't blink when you wiggle them.
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