The humidity sensor module is sensitive to environmental humidity, generally used to detect ambient humidity by adjusting the potentiometer, for detecting the humidity can change the threshold ( i.e. the humidity control), such as the need to control the ambient humidity of 60%, then the corresponding module is transferred to the green light and humidity environment, DO high power output when flat, humidity values below this setting, high output, the green light does not shine DO output can be directly connected to the microcontroller through the microcontroller to detect high and low, thereby detecting the humidity changes in the environment. DO output of the relay module can directly drive the shop, which can form a humidity switch, control-related equipment to work in the right environment. Small plates AO analog output modules can be connected OUR AD through the AD converter, you can get a more accurate numerical ambient humidity With the screw holes of 3mm, easy fixed installation.