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Overview：
A permanent magnet vacuum circuit breaker (short name VCB) is an outdoor high-voltage switchgear used in a three-phase AC 50Hz power grid with a rated voltage of 7.2~12kV. The VCB adopts a permanent magnet operating mechanism, compound with the control terminal and PT (power transformer) to form an intelligent circuit breaker, which is widely applicable to substation feeder terminals, distribution lines of industrial and mining enterprises, and urban and rural power grid transmission and distribution systems for protection and control, especially suitable for places with frequent operations and urban and rural power grid automatic distribution networks.