Electronic Circuit Breaker with Automatic Fault Detection

The purpose of this project is to protect home appliances and industrial appliances and also to provide an indication about the type of fault that has occurred in the system. Hence a microcontroller based protective scheme is proposed which provides protection against faults like Line to Neutral fault and Line to Ground fault. It also provides protection against Earth leakage thus protecting human beings from heavy electrical shocks. In this scheme there is a Voltage sensing circuit which senses the supply voltage and protects the device from over voltage with the help of a triac which acts as an AC switch. The triac is controlled by a firing circuit that produces firing pulses for the triac. A protective relay is added to provide superlative protection in the failure of triac. There is a current sensing circuit which senses the leakage current and also the load current. The output of the current sensors helps in providing protection against earth leakage and short circuit fault or overloading of the supply. There is also a fuse sensing circuit to find the blown fuse and helps in indicating it.