How are fuses typically sized?

Fuses are typically sized by both the voltage and the current rating to ensure proper protection of electrical circuits. The current rating is critical because it determines the maximum current a fuse can handle before it blows, protecting wiring and devices from overcurrent conditions which can cause overheating and damage. The voltage rating is equally important, as it ensures that the fuse can safely interrupt the circuit without failing to properly extinguish an arc when it operates. If a fuse is rated for a voltage that is too low for the application, it could potentially fail to function correctly in an overcurrent scenario, leading to unsafe conditions.

By considering both the current and voltage ratings, fuses can be accurately matched to the specific requirements of the electrical load they are protecting. This ensures not only the safety of the electrical system but also maintains the proper operational integrity of connected devices.