Best Garage Door Sensors in 2020

1 X Liftmaster 85LM Power Adapter Review:

Needed to add Homelink remotes for my old garage door opener, decided to add the Liftmaster 850lm but when I wired it up to my Genie's power it didn't work as planned(voltage was within range). Since I wasn't confident in the power output of my 30 yo Genie unit, I got this AC adapter hoping it just needed a cleaner power source and voila, everything worked perfectly and now I can add all my Homelink transmitters with much improved range.

xin-sheng 3 Sets of MC-38B NC & NO Embedded Magnetic Gap Switch for Door and Window Sensor for Home Security Review:

Needed to put my gate due Z-Wave magnetic sensor out of the way of the rain (which ruined my last sensor). Bought these because they already had wires. They worked perfectly. The magnet worked well, though I ended up using a more powerful magnet due to the gap in my fence. The wires are not marked, but I ended up getting it correct the first time, so no biggie.

Liftmaster 41C4398A RPM Sensor Assembly Review:

When our garage door went wacko, so did my husband. He figured the whole thing was shot and shouted that we were looking at a $300 replacement. I quickly realized that was a lot of shoe money. I climbed my blonde, 5'5" self up a ladder and saw the cutest lavender button on my opener, blinking. A quick Google search diagnosed the problem and I landed here. I was worried about little ole me being able to replace this doohickey, but it was easier than I thought. Like another person said, the hardest part was getting the screws out. It was hot in my garage and I started to sweat, and I don't like that. Anyway, the new part didn't work at first, causing Captain Caveman to wig out again. I finally figured out the the little thingamajig with the prongs on the back wasn't pushed in all the way. Now it worked!!! I bought myself a new pair of shoes a a reward for all the money I saved. Do not pay someone your hard earned shoe money to replace this part. Even I can do it, so can you.

GoodChief Universal Garage Laser Line Parking Assist – an Innovative Way to Easily Park and Guide with Dual Laser Lines Projected on Your Vehicle. Find The Difference on Our Video Review:

The product works, is very small, and looks good (in case you care about how a tiny laser in your garage looks). I like that its black.

- The case is 3D printed. I love supporting small businesses and kudos to Allen for making and selling these. It feels a bit home brew prototype-ish and I was a little bit afraid if it would break when tightening the screws. But it's strong enough and while it might feel rough upon close inspection, it looks good on the ceiling. Moving the laser heads around a bit will smooth the movement.
- You have to connect the power adapter to lasers with open ended cables. The instructions say 'connect with same color' but one cable has a red lead the other a gray print. The set included two tiny wire nuts. I don't like wire nuts, so I soldered it together.
- I installed the lasers under the cover where the light bulb on the garage door opener usually resides. I don't use the internal lights, since we have a motion detector switching the ceiling light on. I took my time, I drilled holes, cut the cables to length, checked if it works before installing it. YOU NEED TO TEST if the laser marks the spot as desired, because in some positions they simply don't line up because of the mechanical limitations of the two pivoting lasers.

Bottom line: It's a good product, and I wish the owner good luck with his business (I don't know him, he just left a friendly note on the box). I purchased the product in August 2019 for $28.

Update: I contacted the owner and he is very friendly.

Sengled Smart Window & Door Sensor, Hub Required, Compatible with Alexa, Google Assistant and SmartThings, 2 Pack Review:

Ohm’s Law says: P=IE
Where P = power in watts, I = current in amperes, and E = voltage in volts.

When looking for a smart plug, that can handle a “heavy duty” appliance (first picture); it is important that you choose a plug that has an OUTPUT CAPACITY of 1,800 watts. The Sengled smart plug meets that requirement.
Ohm’s Law: 1,800 watts = 15 amperes * 120 volts

ALL smart plugs are rated ON THE WALL OUTLET SIDE for 15 amperes at 120 volts, but not many are rated for the full 1,800 watts on the controlled outlet side.

Not only is this smart plug compact; so is the packaging it comes in (second picture). All six sides of the box have printed information! And for the most part, setup is literally a “plug and play” experience (it’s SmartThings certified); so long as you don’t get excited, and just “plug it in,” before being prompted to by your Zigbee hub integration procedure. If you need to reinitialize the plug, simply hold the power button for 10 seconds, while the unit is plugged in. Also, DO NOT plug any appliances into the smart plug, until AFTER it has been paired to your Zigbee hub.

SABRE Wireless Motion Sensor Home Security Burglar Alarm with LOUD 120 dB Siren and 120 Degree Wide Angle Detection - DIY EASY Installation Review:

UPDATE : To whom it may concern....I bought this unit in 2015 as a security feature for an outdoor medical cannabis garden. I was thinking twice when I saw the low price of this unit but 2 years, and 3 crops later this is STILL my "go to" for security in the garden. It'll wake me out of a dead sleep inside my house 100ft away and is very sensitive. I am woken by the raccoons foraging in the berry patch regularly but better safe than sorry right ? You can use them outdoors as long as you build little "birdhouses" for them, but the point is they can save you BIG bucks, and are obviously worth the price if I can get through 3 crops with it ! GREAT little unit !!! Going to buy more myself !

UPDATE 2018 ; This little bugger just keeps working ! Best 20 bucks I ever spent. It's been through just about everything but just keeps going, and going, and going......LOVE IT !

10 Pair RC-33 NC Recessed Wired Security Window Door Contact Sensor Alarm Magnetic Reed Switch White Review:

My alarm sub-contractor did a bad job on the install for my client. Used electrical tape to make the contacts grip the hole he drilled in door frame. And...they popped out and got crushed by the door. I bought these and retrofitted the 3/4" hole in frame with a plug that I drilled a 3/8" hole into in order to install these smaller sized contacts. Worked perfectly!

Wasserstein Smart Door Sensor - Door and Window Movement Detection and Home Automation Review:

This review is for the aesthetics not the functionality.When I opened the box I was amazed at the feel of the device.
Rubbery feel to it. Smaller than the ones I am using right now.
I thought I could connect it to my Hubitat E.
My mistake. It is a WiFi enabled device. Since I am going the ZWave route, integration is not supported at this time to the best of my knowledge.
I am sure you can use it with Echo.
I did very limited research on this product before purchasing.

Leviton ODC0S-I1W Self-Contained Ceiling-Mount Occupancy Sensor and Switching Relay, 1000-Watt, 120-Volt Review:

I bought this sensor thinking 'you get what you pay for'. This sensor works extremely well. A little too good! As other reviewers have mentioned, this senor will activate, even, if no movement is present. A small vibration in the house will set this sensor off (= slamming a door, knocking on the wall, etc...). So I sent it to Leviton in Oregon to check it out. They were extremely friendly and helpful. Especially the last phone call I received was very informative. The unit I sent in was working as intended. However, come to find out, this unit is made for areas of 300 square feet or larger with 12+ feet ceilings. Large garages, barns, etc... (This was NOT in the description!) They have to be sensitive to work well under those circumstances. This sensor is not made for small areas such as bathrooms, closets, etc.... They sent back the original unit AND a unit that WILL work in my situation: a 9 by 9 feet bathroom with 9 foot ceiling. So even though this unit works extremely well, it is not suited for home owner usage, but for large commercial usage. The latter I have not been able to test.