What does a circuit breaker primarily protect against?

A circuit breaker primarily protects against excess current, which occurs when the current flowing through the electrical circuit exceeds the designated limit for that circuit. This situation can lead to overheating, potential fires, and damage to electrical devices if not addressed quickly. The circuit breaker serves as an automatic switch that interrupts the flow of electricity when it detects excessive current, preventing damage and ensuring safety.

While overvoltage, short circuits, and voltage spikes can also be concerns in electrical systems, the primary function of a circuit breaker is to respond to excess current. Overvoltage and voltage spikes are typically managed by other protective devices, such as surge protectors or voltage regulators, while short circuits often trigger the circuit breaker due to the sudden surge in current they create. Thus, the emphasis on excess current as the main protective measure highlights the circuit breaker’s essential role in maintaining electrical system safety.