What is the main function of a circuit breaker?

A circuit breaker is designed primarily to enhance electrical safety within a system by automatically shutting off electricity during an overload or short circuit condition. This function is crucial because excessive current can lead to overheating, which poses a significant fire risk and can damage electrical devices. When the circuit detects an unsafe level of current flow, the breaker opens the circuit, stopping the current and mitigating potential hazards.

The ability to reset a circuit breaker after it has tripped is another key feature, allowing it to be used repeatedly without needing to replace any components, unlike fuses, which must be replaced once blown. This characteristic makes circuit breakers reliable and efficient safety devices in residential and commercial electrical systems.

Other options focus on functions that either do not align with the purpose of a circuit breaker or represent irrelevant tasks such as increasing electrical flow or providing additional voltage, which are functions more suited to transformers and power supplies. Managing device connections is also not an essential function of a circuit breaker; that role is typically managed by switches and other devices within an electrical system.