The principle and function of vacuum circuit breakers

Vacuum circuit breakers are indoor distribution devices in a 3~10kV, 50Hz three-phase AC system. Its main function is to control and protect current and voltage in medium and high voltage transmission lines. It can be used for the protection and control of electrical equipment in industrial and mining enterprises, power plants, and substations. It is particularly suitable for drying requirements. In places with maintenance and frequent operation, circuit breakers can be installed in intermediate cabinets, double-layer cabinets, and fixed cabinets to control and protect high-voltage electrical equipment. The following will provide a detailed introduction to the working principle and function of the device.

1. Working principle

Under normal circumstances, a low-voltage area is formed between the two contacts of a vacuum circuit breaker, resulting in low conductivity. When overcurrent or overvoltage occurs, the low-pressure area will be instantly ionized, forming an arc and absorbing energy. At the same time, as the current gradually decreases, the low-pressure area will also be formed again, leaving a small hole on the metal surface next to it. Due to the almost absence of gas molecules in a vacuum environment, both the temperature of the arc and the fluctuation of voltage have minimal impact, enabling it to better support transient currents in high power systems.

2. Function

The main function of vacuum circuit breakers is to disconnect or switch the current in transmission lines to protect the normal operation and safety of the power system. It can also be used to maintain the interconnection and traversal of load power sources in the power system.

3. Characteristics

Vacuum circuit breakers have many characteristics that other types of circuit breakers do not have, such as being able to restart quickly after a fault; Do not produce toxic, corrosive gases or other pollutants; Misoperation is also less likely to occur when environmental parameters such as temperature changes and voltage fluctuations change.

The ZC-313 vacuum tester abandons the traditional withstand voltage method and uses the magnetic discharge method for measurement, which eliminates the need to disassemble the arc extinguishing chamber. The use of a single chip microcomputer for synchronous control and data acquisition processing improves the on-site testing sensitivity of the vacuum degree of the arc extinguishing chamber. This product has a compact structure, a lightweight and compact model, shorter testing time, higher measurement reliability, stability, accuracy, and more complete functions.

Kvtester Electronics Technology Co.,Ltd. is a high-tech enterprise specializing in power testing, testing, research and development, production, and sales of testing equipment. It has been engaged in the electrical testing industry for many years, and its products are of high quality. We welcome customers to come and purchase.