The characteristics of vacuum circuit breakers are as follows:

① The contact opening distance is small. For a 10KV vacuum circuit breaker, the contact opening distance is only about 10mm. With such a small opening distance, the operating force of the operating mechanism is low, the mechanical part’s stroke is short, and thus the mechanical life is long.

② The arc ignition time is short and is independent of the magnitude of the switching current. Generally, it is only half a cycle.

③ After arc extinction, the medium in the contact gap recovers quickly, and it performs well in interrupting faults in the near zone.

④ Due to the relatively small wear of the contacts during the process of breaking the current, the electrical lifespan of the contacts is long. They can withstand 30 to 50 full-capacity breaking operations and more than 5,000 breaking operations at rated current. The noise is low and they are suitable for frequent operation.

⑤ Compact in size and light in weight.

⑥ Applicable for breaking through capacitive load current.