Outdoor double/single porcelain pillar type vacuum circuit breaker adopts high reliability vacuum arc extinguishing chamber and operating mechanism of Ming electric house. Vacuum arc extinguishing chamber special high edge strength, high vacuum degree arc extinguishing medium, supporting excellent contact manufacturing process can quickly and frequently break the large current, not only can break the load circuit, and can effectively break the short circuit fault circuit, to protect other power transmission and transformation equipment from damage. Over the years, the vacuum circuit breaker of Ming Electric House has been widely used in Japan and other areas of electrified railway.