Final answer:
A circuit breaker serves the same purpose as a fuse by interrupting excessive current in electrical circuits to prevent overheating and potential fire hazards. While a fuse must be replaced after tripping, a circuit breaker is designed to be reset. Advanced circuit breakers use technologies like insulating gas and gas jets to manage high-voltage interruptions.
Step-by-step explanation:
A circuit breaker often serves the same purpose as a fuse. Both devices are crucial for preventing thermal hazards by interrupting excessive currents in electrical circuits. Circuit breakers and fuses act as automatic switches that open when sustained current exceeds desired limits, stopping the flow of electricity to protect against overheating and potential fires.
Circuit breakers, however, are designed to be resettable, while fuses need to be replaced once they melt due to an excessive current. Fuses contain a metal strip with a low melting point, and when the current is too high, this strip melts, permanently breaking the connection. In contrast, a circuit breaker uses a bimetallic strip that bends and triggers a mechanism to break the circuit, which can then be reset manually or automatically.
Large circuit breakers, especially those found in power-distribution systems, employ more advanced technologies to interrupt high-voltage electricity, such as insulating gas and gas jets to prevent sparking that can maintain current flow. It's noted that AC current is typically safer to interrupt than DC since it goes through zero voltage 120 times per second, providing natural moments to extinguish any arcs.