Vacuum circuit breaker works with other circuit breakers different compared to the arc medium Bale breaker factory direct, conductive medium vacuum does not exist, so that the arc quickly extinguished, so few moving contacts of the circuit breaker spacing between. The circuit breaker is generally used for relatively low voltage auxiliary power configuration! With the rapid development of power system vacuum circuit breaker factory outlets, 10KV vacuum circuit breakers have been produced and used in large quantities in China. For maintenance personnel, to improve understanding of the vacuum circuit breaker, strengthen maintenance, making it safe to run, it has become a pressing issue. In this paper, ZW27 - 12 as an example, a brief description of the principles and maintenance of vacuum circuit breakers. Within ZN28A-12 series indoor high voltage vacuum circuit breaker (within ZN28-12 integrated indoor high voltage vacuum circuit breaker) ◆ use of environmental conditions Ambient temperature:. -10 ℃ ~ + 40 ℃ (allow storage at -30 ℃ when);. Relative humidity: daily average of not more than 95%; on average less than 90%; daily average saturated vapor pressure of not more than 2.2kPa; Altitude: not exceed 2000m (2500 to plateau); monthly average saturated vapor pressure of not more than 1.8kPa; seismic intensity: less than 8 degrees; no fire, explosion, severe contamination, chemical corrosion and severe vibration. Welcome to inquire! Breaker factory outlets | Huayi Electric Power (certified) | Haikou breaker provided by Xian Huayi power plant. Xian Huayi Electric Power Equipment Factory (www.xahy.com) is a leader in Xi'an high-voltage circuit breakers, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. In Huayi Electric Power leadership with the staff warmly welcome all inquiries negotiations to create Huayi electricity better future.