What is the function of a fuse in an electrical circuit?

The function of a fuse in an electrical circuit is to protect against excessive current. A fuse is designed to allow a specific amount of current to pass through it under normal operating conditions. However, when the current exceeds this predetermined level—due to short circuits, overloads, or malfunctions—the fuse will heat up and eventually melt. This interruption in the flow of current prevents potential damage to other components in the circuit, such as wiring, devices, or equipment, which could occur if excessive current continued to flow.

Understanding the role of a fuse is crucial for safe electrical design and usage. While other functions such as regulating voltage levels or measuring power consumption are vital in electrical systems, they are not tasks performed by a fuse. Similarly, increasing resistance is unrelated to a fuse's purpose, as fuses do not function to adjust resistance in the circuit. Their sole purpose is to act as a safety device to prevent overcurrent conditions.