What is the function of a circuit breaker?

The function of a circuit breaker is to automatically interrupt the flow of electricity in case of a fault. This is crucial for electrical safety, as circuit breakers are designed to protect electrical circuits and prevent damage that could be caused by overloads, short circuits, or other disruptions. When a fault occurs, the circuit breaker senses the abnormal electrical conditions and disconnects the circuit, stopping the flow of electricity. This helps to prevent potential hazards, such as electrical fires or equipment damage, ensuring that the electrical system remains safe and operational.

Given the other options, increasing electrical flow when demand exceeds supply is not a function of a circuit breaker; rather, this would typically require a different type of device such as a transformer or load management system. Measuring voltage is a task usually performed by a voltmeter, not a circuit breaker. Finally, converting alternating current to direct current is the role of a rectifier, which is unrelated to the protective function of a circuit breaker.