Fuse is a safety component that needs to be able to safely blow without damaging the surrounding circuit. Breaking capacity is one of the indicators to ensure that a fuse can safely break a circuit.

Breaking capacity is the maximum current value at rated voltage at which a fuse can safely break a circuit without rupture. The breaking capacity of a fuse must be equal to or greater than the maximum fault current that may occur in the circuit. If the current in the circuit exceeds the fuse’s melting current and falls below the breaking capacity, the fuse will safely open without damaging the circuit. If the current in the circuit exceeds the breaking capacity, although the fuse will also break, there is a possibility that it will shatter or explode, which will cause damage to the circuit.

The breaking capacity of a fuse depends on the construction of the fuse and the material used. Generally, most low breaking capacity fuses are glass housed; high breaking capacity fuses usually have ceramic housings, many of which are also filled with pure granular quartz material. Breaking capacity is also related to the fuse’s current rating and load voltage. The higher the current rating, the greater the breaking capacity; as the load voltage increases, the breaking capacity will decrease.

In order to ensure the safety of the fuse, we need to consider the current capacity, melting characteristics, pulse resistance and aging speed, impedance and power consumption, temperature discount and other necessary performance parameters in addition to the selection of fuses, but also need to take into account the breaking capacity, rated voltage and safety certification and other safety indicators.