What is an electronic fuse?
A fuse is a commonly used safety device in circuits, also known as a current fuse. It is mainly composed of a conductor part and a protective shell. The conductor part is usually made of alloys with lower melting points such as lead and tin, and presented in the form of wires or strips. The following is a detailed explanation about fuses:
1、 Function
The main function of a fuse is to automatically cut off the power supply when the current in the circuit exceeds the set value, preventing circuit overload, short circuit, malfunction, and equipment damage. Specifically, it can cut off the current by melting itself when the current rises abnormally, thereby protecting the safe operation of circuits and electrical equipment.
2、 Working principle
The working principle of fuses is based on thermal effects. When current passes through a fuse, heat is generated due to the inherent resistance of the conductor. Under normal circumstances, the heat generated is not sufficient to blow the fuse. But when the current in the circuit exceeds the rated value of the fuse, the heat generated will rapidly increase, causing the temperature of the fuse to rise. When the temperature reaches the melting point of the fuse, the fuse will melt, thereby cutting off the circuit.
3、 Characteristics
Electrical resistivity: The material of the fuse has a high electrical resistivity, which can generate a large amount of heat in a short period of time, promoting fuse protection.
Melting point: The melting point of a fuse should be lower than the temperature that the protected electrical appliance and circuit can withstand, in order to melt in a timely manner when the current is overloaded.
Disposable: Fuses are usually designed for one-time use because their conductivity cannot be restored after melting.
