What is the purpose of fuses in an aircraft electrical system?

Fuses play a critical role in enhancing the safety and reliability of an aircraft's electrical system by preventing overcurrent conditions. When the current flowing through a circuit exceeds the rated capacity of the fuse, the fuse element melts due to the increased heat generated by the excessive current. This melting effectively breaks the circuit, stopping the flow of electricity and preventing potential damage to electrical components, wiring, and even the risk of fire.

Fuses are not designed to regulate voltage or act as a power amplifier, nor do they serve to improve energy efficiency. Instead, their primary function is to provide a safety mechanism that protects the entire electrical system from the dangers associated with overcurrent, ensuring that everything from control systems to onboard equipment operates safely within their intended electrical limits.