A Text Book of an Automatic Solar Powered Irrigation Farming System

This project present the design and construction of Automatic solar powered irrigation farming system using NE555 Timer, 7404 HEX inverter, Transistor SK100 and Relay, the system will work when two probes which are connected to the circuit are placed/inserted in to the soil, two probes will conduct only when the soil is wet (resistance is low) and they cannot conduct when the soil is dry due high resistance. The voltage is given from the battery connected to the circuit. When the soil is dry it will produce large voltage drop due to high resistance .This is sensed by 7404 Hex Inverter and makes the first NE555 Timer trigger which is configured as Monostable Multivibrator with the help of an electrical signal. When the first NE555 Timer is triggered at Pin 2, it will generate the output at pin 3 which is given to the input of second NE555 timer. The second NE555 Timer is configured as Astable Multivibrator which got triggered by the first NE555 timer and will generate output and drive the Relay which is connected to the electrically operated value through the Transistor SK100. I can use a heat sink for SK100 transistor if it is dissipating more heat.