The rain sensor detects water that completes the circuits on its sensor boards’ printed leads.
The sensor board acts as a variable resistor that will change from 100k ohms when wet to 2M ohms when dry.
In short, the wetter the board the more current that will be conducted.
This module allows the measurement of moisture through analog output pins and it provides a digital output when a threshold of moisture is exceeded.
The module is based on the LM393 op amp.
Working voltage: 3.3V-5V
Low power consumption
On-board indicator LED to show the results
Digital output and Analog output
Dimension of the board: 3.2cm x 1.4cm