It’s a common application for a wireless security system, but it sounds like you want to use BLE instead. I’m not aware of a ready-made BLE contact sensor, but you could get a ready-made BLE 9-axis IMU sensor, set it for a slow data rate to conserve battery, and just monitor the magnetic field sensor value. Should change a lot when the gate magnet is nearby! You could also start with a BLE click-button, then hack in to connect your gate sensor to the button contacts. Finally, you could build your own, which will be the most work and the most fun.
Hi @gusgonnet , here’s something you might consider. I’ve been using some of their sensors, such as leak detection, PIR, outdoor PIR, etc. with great success. They’re based on LoRa which means the range is crazy long and the price point is great. The devices are inexpensive, but will also require a base station, which is also relatively inexpensive. In any case, it’s food for thought. You can integrate with Particle via IFTTT if desired.
Also, netvox makes a Wireless Dry Contact Interface R718J that’s also LoRa and could likely be used to send data directly to a Particle device with a LoRa Featherwing. FWIW…