To ensure the safety of onboard electrical appliances and passengers, and to prevent the occurrence of short circuits and overloads, fuses are generally used for protection. The following is a high-voltage fuse manufacturer to tell you about the basic structure, symbols, main functions, and protection devices of high-voltage fuses.
The basic structure of high voltage fuse
The high-voltage fuse is mainly composed of three parts: the melt, the melting tube for installing the melt, and the melting seat.
1. Melt
Melts are often filamentous, sheet-like, and grid-like, and are the main components of fuses. According to the thermal inertia of the melt, they can be divided into melts without thermal inertia, melts with large thermal inertia, and melts with small thermal inertia. melt.
2. Melting tube
The melting tube is the outer shell of the melt, which is made of heat-resistant insulating material, and has the function of arc extinguishing when the melt is fused. The rated current value of the fuse tube. The so-called rated current of the melting pipe refers to the current value determined by the allowable temperature rise of the melting pipe for long-term operation.
3. Fusion seat
The function of the fusion seat is to fix the fusion tube and the external lead wire. When the fuse is connected to the circuit, the melt is connected in series in the circuit, and the load current flows through the melt. When a short circuit or overcurrent occurs in the circuit, the current through the melt makes it heat up; when it reaches the melting temperature of the molten metal, it will fuse itself, and the fault circuit will be cut off along with the arc burning and arc extinguishing process to play a protective role.
What is the symbol for a fuse?
The text symbol of the fuse is FU, and the text symbol of the old fuse is represented by RD.
What is the main function of a high voltage fuse?
The function of the high-voltage fuse is short-circuited protection. When the circuit or the equipment in the circuit is overloaded or fails, the current of the circuit in which it is located exceeds the specified value and after a certain period, the fuse of the high-voltage fuse heats up and melts, thereby cutting off the circuit and breaking the current. , to achieve the purpose of protecting the circuit or equipment.
High-voltage fuses are connected in series in protected circuits and equipment (for example, high-voltage transmission lines, power transformers, voltage transformers, etc.), and are mainly used for short-circuit protection, but some also have overload protection functions.
What are fuses mainly used for protection?
After the fuse is opened, it acts as an overcurrent protection. Its principle is that the heat generated when the current is too large will melt the fuse so that it can play a certain protective role. The fuse is to protect the normal operation of the circuit and can protect the equipment from damage.