Electrical Circuits Application

While electrical circuits themselves are used everywhere in our everyday lives, the concepts behind electrical circuits have led to the practical use of safety devices such as circuit breakers. Circuit breakers that are used at the distribution board in houses are called MCB's or miniature circuit breakers. Essentially, breakers limit the current which can flow through a circuit. In a breaker, the heating effect on a bimetallic strip causes it to bend and trip a spring-loaded switch. Typically a single circuit is limited to 20 amperes, although this can vary. When there is a short circuit, which creates a large surge of current, a small electromagnet consisting of wire loops around a piece of iron will pull the strip, separating the contacts and breaking the circuit. After the fault causing the short circuit is repaired, the contacts can be pushed together by lifting a switch on the outside of the circuit breaker.

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