Time delay fuses are most commonly used in circuits subject to which type of current?

Time delay fuses are specifically designed to handle temporary surges or inrush currents that can occur when electrical equipment starts up. This inrush current can be several times higher than the normal operating current, especially in inductive loads like motors or transformers.

These fuses provide a built-in delay that allows the initial surge to pass without blowing the fuse, preventing unnecessary interruptions in power supply. After the delay period, if the current exceeds the fuse's rating during normal operation or due to a fault, the fuse will then blow to protect the circuit.

While both AC and DC currents can have inrush characteristics, time delay fuses are particularly associated with circuits that experience significant surges whenever motors and similar devices are powered up. This makes them essential for managing inrush currents effectively.