Soil Moisture Controller Module Board Kit Automatic Watering Device Automatic Watering DIY Electronic Production Parts Diy Kit

product manual:The soil moisture controller detects the soil moisture through the soil moisture sensor (fork-shaped circuit board). The soil moisture sensor is not conductive in the air. After inserting the soil, the more moisture in the soil, the resistance on the two terminals of the humidity sensor. The lower, the greater the resistance. The sensor's signal is connected to the control circuit through the J2 probe interface. The resistor R2 is connected in series on the humidity probe. The change in humidity is reflected as the change in the voltage at the inverting input of the voltage comparator U1A. If it is lower than the voltage at the same input terminal of U1A, the comparator outputs a high level, otherwise the output is low. Flat, capacitor C2 is a stable output signal to prevent the relay frequency from operating when the humidity is detected. The self-locking switch J3 is used to control the action mode of the relay (whether the high-level pull-in relay is outputted in th