ZW7-40.5Series outdoor high voltage vacuum circuit breakers are main switchgear of AC 50Hz, 40.5KV. which is assembied with spring operating or electromagnetic operating mechanism. lt can be operated to switch on/off by remote control, and it is also charged and switched on/off by hand. The design function of breaker complies with the requirements of GB1984-89 and IEC-56 AC high voltage circuit breaker, it is mainly used outdoor 35KV distribution system to control and protect, also for normal operating and protecting short circuit of urban, rural network, enterprises. Its overall structure is supported by porcelain insulator, vacuum interrupter built in upper insulator, downside insulator used for supporting. The breaker applies to frequent operating places, with the advantages of good sealing, anti-aging. high voltage withstand, non flame. non explosion long working life, easy installation and maintenance and etc.