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

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

Was actually a NC contactor for an old school buzzer using 12v. Many others come NO without the three wires.

It looks very well made, it was easy to install, and works great so far!

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.

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,

Todo bien

Well made. Fast Delivery. I mounted it over my garage door on the wall and the Magnet bracket to the door. Will last forever up there. It has a strong magnet and activates when the Garage door opens an inch. Hooked to to a low volt LED light inside the hall leading to/from garage. Lites the way! And warns if garage is ope.

Buy this one instead of the Honeywell Contacts because this one have contacts for both Normally Open (NO) and Normally Closed (NC) circuits so I use one for my alarm and another circuit for indicator for the garage doors are open or closed. There are no label the wires so you need to test it with test meter. Need to connect to a relay if pull more amperage or volts. The distances apart can be up to 2 inches.

I purchased this to replace a cheap unit on a NexxGarage controller. The magnetic range and quality of this unit is great. It can be configured as NO or NC.

It works on my garage door. Now I can tell when it is open. Good Product.