What is the function of a circuit breaker?

The function of a circuit breaker is to protect electrical circuits from overloads or short circuits, which is why the correct answer is focused on this key role. Circuit breakers are safety devices designed to automatically interrupt the current flow in a circuit when it detects a fault, such as an overload or a short circuit. This action helps to prevent damage to wiring, appliances, or equipment, and reduces the risk of electrical fires or other hazards.

By monitoring the electrical flow, when the current exceeds a safe level, the circuit breaker trips, effectively shutting off the circuit. This protective mechanism is critical in ensuring safe operation of electrical systems.

The other choices, while related to electrical systems, do not accurately describe the primary role of a circuit breaker. For instance, converting AC to DC refers to the function of power supplies or converters, regulating voltage is typically handled by voltage regulators, and measuring electrical signals falls under the domain of measuring instruments like multimeters or oscilloscopes. Each of these functions serves its own purpose in electrical systems, but they do not encompass the protective function of a circuit breaker.