Vacuum circuit breakers use vacuum as the arc extinguishing and insulating medium. The parts are sealed in a shell made of insulating glass and other materials, and the sealing of the movable contact rod and the movable contact is realized by a metal bellows.

The empty circuit breaker has the following characteristics:

1. Lightweight structure, small contact distance (10 kV, only 10 mm), rapid action, light operation, small size and light weight.
2. The arcing time is short. Because the contact is in a vacuum, basically no arc occurs. Very small arcs generally only need half a cycle (0.01 seconds) to extinguish, so it is called a half cycle circuit breaker, and it is related to current The size is irrelevant.
3. The recovery speed of contact gap medium is fast.
4. Long service life.
5. The maintenance workload is small, and it is fireproof and explosion-proof.

At present, vacuum circuit breakers have been more and more widely used, especially 10 kV circuit breakers are used more and more vacuum circuit breakers. But pay special attention to the quality of the vacuum circuit breaker when selecting.