What is the main purpose of a circuit breaker in an electrical system?

The main purpose of a circuit breaker in an electrical system is to protect circuits from overload and faults. Circuit breakers serve as safety devices designed to prevent excessive current flow, which can lead to overheating, equipment damage, or even electrical fires. When a fault occurs, such as a short circuit or an overload situation, the circuit breaker automatically interrupts the electrical flow, effectively isolating the affected circuit and preventing further damage. This automatic disconnection is crucial for maintaining safe operation within electrical systems.

While circuit breakers can have roles related to controlling voltage levels, improving efficiency, or even functioning as a manual switch to enable or disable circuits, these features are secondary to their primary function of providing protection. The ability to trip and isolate a circuit during dangerous conditions is what fundamentally defines their importance in electrical safety.