What are the advantages and disadvantages of a vacuum circuit breaker

Vacuum circuit breaker refers to a circuit breaker whose contact is opened and broken in vacuum, and USES vacuum as the insulating medium and arc extinguishing medium. It has the following advantages:

Strong arc extinguishing ability, short arc burning time and short total breaking time.

Parliamentary contacts have small opening distance and long mechanical life.

Torque is suitable for frequent operation and quick cut-off, especially for cut-off of capacitive load circuits.

Low volume, light weight, low maintenance workload, no maintenance required for vacuum arc extinguishing chamber and contacts.

There is no inflammable or explosive medium, and there is no danger of explosion or fire.

The vacuum circuit breaker also has some disadvantages due to its structural characteristics:

It is easy to generate operating overvoltage, mainly when switching off small current, interception overvoltage and high frequency multiple ignition overvoltage. Therefore, the vacuum circuit breaker should generally adopt effective measures to suppress operating overvoltage.

The vacuum degree of the extinguishing chamber can not be checked at any time during operation, and it can only be checked by special pressure test or special instrument. When the vacuum degree is reduced or cannot be used, only replace the vacuum arc extinguishing chamber.