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

The primary purpose of a circuit breaker in an electrical system is to automatically shut off electrical flow in the event of overload or short circuit conditions. This safety device acts as a protective measure, preventing excessive current from flowing through electrical circuits which can lead to overheating, potential fires, and severe electrical hazards. By interrupting the circuit, the circuit breaker minimizes the risk of damage to appliances and wiring and ensures the overall safety of the electrical system.

When an overload or a short circuit occurs, the circuit breaker detects the abnormal increase in current and quickly opens the circuit, effectively stopping the flow of electricity. This interruption not only protects the electrical devices connected to the circuit but also safeguards individuals from electrocution and other electrical-related injuries.

The other options do not accurately describe the fundamental role of a circuit breaker, which is inherently focused on safety and fault protection rather than enhancing flow, manual control, or monitoring output levels.