1. What is a fuse?

A fuse is a replaceable circuit protection device that provides protection to both the equipment and the equipment operator in the event of a circuit overload. It is commonly connected with a circuit in series, and when fault current increases to a certain value, the fuse blows out to cut off the circuit so as to fulfill an aim of protecting other equipment in the circuit. The fuse is the most commonly used component in an overcurrent protection circuit. The traditional fuse mainly consists of two parts of a tube body, of which both ends have metal connecting terminals, and metal melts in the tube body. The majority of fuses are cylinder-shaped, namely cartridge construction.

2. Fuse's function

The fuse can bear overload in a certain range when current fluctuation occurs because of power supply or external interference;

When bigger overload current appears in the circuit, the fuse should cut off the circuit in the set time so as to protect other electric parts in the circuit;

When very big current appears because of short circuit, the fuse can safely cut off the circuit so as to avoid damage by overload current.