How are electrical circuits in an aircraft typically protected?

Electrical circuits in an aircraft are typically protected using both circuit breakers and fuses, which provide layers of safety and redundancy in the system.

Circuit breakers are resettable devices that automatically cut off electrical flow if a fault or overload occurs. This ability to reset allows for easier troubleshooting and can reduce downtime during flight operations. They come in various ratings to accommodate different circuits' current limits, ensuring that if an overload happens, only the specific circuit is affected while protecting the overall integrity of the electrical system.

Fuses, on the other hand, are one-time use protective devices that melt under excessive current, thus breaking the circuit and preventing further electrical flow. They serve a similar purpose as circuit breakers but require replacement once they have operated.

Using both devices in tandem enhances the overall electrical safety within the aircraft. Circuit breakers can be more efficient for systems that may need to be reset frequently, while fuses are typically used in lower-powered or critical circuits where a quick, definitive action is needed. This comprehensive approach to protecting electrical circuits helps prevent electrical fires and equipment damage, ensuring the safety and reliability of the aircraft.