Rain Sensor used to detect the presence of rain and used as a switch. This is helpful for farmers, automatic car wiping systems.
This is available in both wired and wireless format. This contains a Hygroscopic disk which says about the presence of water by swelling in the presence of water and shrinks in the absence of water. The wired and wireless sensor works on the same principle. They act as Switch in the Irrigation purpose. There are two parts namely Sensing and Controller part. They provided along with a valve in order to open or close the switch which in turn says about the moisture content in the soil. This sensor detects the beam intensity change and raindrop size falling on the sensor. If the sensor is subjected to Digital processing and some circuitry means even small droplets of rain is easily found.
They also have a freeze sensor in order to work them in freezing temperatures, where farmers do irrigation even in Winter season.
Working of Rain Sensor:
The sensor infrared light into the windshield at a 45-degree angle. If the glass is dry, most of this light reflected back into the sensor by the front of the windshield. The water droplets are on the glass, they reflect the light in different directions, the wetter the glass, the less light makes it back into the sensor.
If there is a presence of water, the light will reflect in different directions. The sensor receives less light and this detects the presence of water. If there are no water droplets, the light will directly reflect in the sensor and this decreases the resistance which in turn increases the voltage.
The presence of water decreases the voltage i.e) resistance is increased.
- A0- Analog Data Output
- D0- Digital Data Output
- Automatic Gardening System
- Car Wiping system
- Irrigation Purpose
- Satellite communication