YL-83 Rain Sensor (FC-37, MH-RD), Water and Humidity Detection Module for Arduino

The YL-83 rain sensor (also known as FC-37 or MH-RD) is an electronic module for detecting water, raindrops or elevated humidity on the surface of its sensing board. The module is widely used in automation projects and environmental monitoring systems. The device consists of two parts: the sensing panel with nickel-plated conductive tracks, the control board with a comparator and a sensitivity potentiometer. When water lands on the sensing plate, its electrical resistance changes. The control board detects this change and generates a corresponding signal at the output. The module provides an analog output (AO) for measuring moisture level and a digital output (DO) that triggers when a set threshold is reached. The detection threshold is easily adjusted with the built-in potentiometer. The YL-83 is ideal for educational projects, smart home systems, automatic irrigation, weather stations and other DIY developments. Product specifications Model: YL-83 Alternative names: FC-37, MH-RD Device type: rain / water sensor Purpose: detection of rain, moisture and water Operating principle: change in resistance of the sensing plate when water is present Outputs: analog (AO) digital (DO) Sensitivity adjustment: potentiometer Operating voltage: 3.3–5 V Compatibility: Arduino, ESP8266, ESP32 and other microcontrollers Package contents: sensing plate control module Applications: automatic irrigation systems weather stations smart home systems water leak monitoring educational and DIY projects