An indoor high-voltage vacuum circuit breaker is a power switchgear that utilizes a high vacuum environment to extinguish electric arcs. It is primarily used in indoor power distribution systems ranging from 3kV to 35kV. Operating environment of vacuum circuit breaker: A Ambient air temperature: upper limit +40℃, lower limit -15℃; b Altitude: ≤100m (if higher altitude is required, the rated insulation level should be correspondingly increased); c Amplitude: Seismic intensity not exceeding 8 on the scale; The daily average relative humidity of the air is not greater than 95%, and the monthly average is not greater than 90% e. Locations free from fire and explosion hazards, severe pollution, chemical corrosion, and intense vibration.