Generally speaking, a circuit breaker is a type of switch that protects us from dangerous electrical situations by automatically turning off the flow of electricity when an overload or other fault occurs.

There are two arrangement of operation of miniature circuit breaker. One due to thermal effect of over current and other due to electromagnetic effect of over current. The thermal operation of miniature circuit breaker is achieved with a bimetallic strip whenever continuous over current flows through MCB, the bimetallic strip is heated and deflects by bending. This deflection of bimetallic strip r...