I recently picked up two of these:
http://www.staples.com/Ecolink-Wireless-Garage-Door-Tilt-Sensor-White/product_278640
haven’t seen this one mentioned on here so i figured some might be interested in my experience.
i was going to use one of my schlage nexia sensors wired up to an external reed switch but settled on these after finding them; $35 and possibly of working right out of the box with smartthings was too much of a temptation.
they show up as standard z-wave contact sensors and work no problem; they’re from taiwan like the schlage sensors so i suspect they might have the same heritage (yet to investigate the pcb in detail etc). just like the schlage sensors, they sport a 2 wire header.
they appear to work with a simple mechanical tilt sensor like this:
it’s mounted at an angle (see pic below) and gets triggered on a ~45deg angle. I bent mine outwards a little so they get triggered a little sooner (~30deg)…this way once my topmost garage door panel is coming up halfway, the sensor triggers. not as direct as a reed switch but works well enough for my purpose.
inside the box:
