Automatic control of agricultural pumps based on soil moisture sensing

In this paper, we investigate the design and simulation of an electronic system for automatic controlling of water pumps that are used for agricultural fields or plant watering based on the level of soil moisture sensing. The detected signal from the soil moisture sensor is processed by a conditional comparator circuit corresponding to different levels of actual soil moisture content. A logic circuit follows the conditional circuit with its output signals used to activate a system of relays that control the power circuit of the motors used for water pumping. The speed of the motor is varied according to the level of the soil moisture content; the motor is OFF during maximum wet and is running with HIGH speed during dry soil conditions respectively. The duration of water pumping is controlled by a timer circuit where the timer can be designed according to the desired watering time. The different stages of the overall electronic system are simulated and tested using NI MULTISM simulation software. The technique is useful to save human-power, enhances crop or plant productivity, saves water and provides proper water management to ensure efficient and viable farming industry especially in those places that receive less rain or mostly dry areas.