S
Spehro Pefhany
Garage Door Safety Sensors... anyone know how they work.
I'm surfing my ass off, even perusing patents, but I can't find how
they work.
Each end has two wires, black and white.
They are connected black-to-black and white-to-white, then connected
to two terminals on the motor controller.
I can't find a schematic for any portion of it.
(I'd like to simply buy a set, provide my own equivalent to that in
the door controller and use for a different purpose.)
Anyone know how they work?
...Jim Thompson
--
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I love to cook with wine. Sometimes I even put it in the food.
Some clues here
"Under U.S. federal law (UL 325), garage door openers manufactured for
the U.S. since 1993 must include a safety reversing system, such as
photoelectric eyes mounted no higher than six inches above the ground,
with a light beam spanning the door opening. The garage door opener is
required to reverse the door to the open position if the beam is
broken.[9] Other examples of safety reversing systems, allowed within
the guideline of UL 325, include electric safety edges, which reverse
with approximately 15 pounds of downward pressure, and a garage door
and opener system without photo eyes, tested together, which reverses
upon approximately 15 pounds of pressure.[10]" This is from
Wikipedia. See:
<http://en.wikipedia.org/wiki/Garage_door_opener#Safety>
What mechanism is used in automatic reversing power windows in cars to
reverse direction when there is an obstruction?
Howard
I think they're just simple modulated IR beams with integrated IR
demodulators (similar to IR remote control receivers), such as this
one:
http://www.biltek.tubitak.gov.tr/gelisim/elektronik/dosyalar/3/IR_sfh506.pdf
All the rest of the smarts resides in a microcontroller.
Best regards,
Spehro Pefhany