SM-226L-3Q Seco-Larm Overhead Door Mount N.C. Magnetic Contact w/ 3 Wires for N.O./N.C. Applications (One Pack)

Item as listed Worked great.

This was needed to replace a failed magnet switch which Id bought about a month earlier to make an indicator light for my garage door. I wish Id gone this route the first time. This item is very high quality and was easy to install as it is made for this application.

Has three wires black is Colin plus one for normally open and one for normally closed . Even without instructions . Hook up black plus one other and see if it signals it closed with the door closed .

Good quality unit

Installed and works perfectly. Mounting bracket for the magnet leaves lots of options. I moved the magnet on all three and trimmed the bracket on two. East to make work for my doors. I installed them on the top of the door with the contact on the overhead door opening.

Perfect switch to be used in a basic DC electronic circuit that detects if the garage door is opened or closed. Provides a visual piece-of-mind that the door is closed,

So, 5 stars for quality, but yikes, $20 for a magnet sensor, so 4 stars for value. Anyway, I bought a Nexx garage door wifi control which is just a repurposed $5 Sonoff control with a very cheap magnetic sensor for reporting door position, but it also has a fairly good app (so you pay for the app I guess). Read the reviews on the Nexx, a large number talk about it working and then not, becaue the position sensor stops reporting correctly. and thats because It needs an 1/8 gap on a garage door. On my wobbly old door youre never going to get that consistency; so Sentrol to the rescue with their 2 inch gap. This sensor is industrial quality. Buy a LeMotech ABS Plastic Dustproof Waterproof IP55 Junction Box, cut the cord on the cheap magnet, and splice it into the Sentrol inside this box. Two day shipping, problem solved. Oh, and use the black and green wires from the Sentrol for this application.

Using as a sensor with a Raspberry Pi. Working perfectly so far. Straightforward install.

I used these switches to put indicator lights in the house so I would know if the garage doors are open or closed. I have used a wireless type of system before, but many times got error message. These wired sensors were installed on top of wall above garage door with magnetic on the door. I wired them to a green light for close and red light for open for each door, using the N/C and N/O contact to turn on the correct light. They worked great and now have a wired system to make sure garage doors are closed.

Very well built. I used this to trigger indicator lights on our driveway gate. Both parts mounted to post and gate with no modifications necessary. The included bracket has plenty of mounting options. I was concerned at first that with the gate being steel if it would affect the magnet, it doesnt. Also, the switch does not have to be mounted as close as possible to the magnet, it will work when the components are about 2 inches apart. Had to mount them farther apart than expected and it still worked fine. The only recommendation I would make to the manufacturer is that the recessed areas to mount the switch be enlarged slightly. The recess is too small to get a socket on a hex head screw making it necessary to use Phillips screws.