Yuanky ZW20A‑12 series outdoor HV vacuum breaker is an improved model of ZW20‑12 pole mounted vacuum circuit breaker, adopting Japan Toshiba VSP5 gas sealing, explosion-proof and insulation structure technology to realize excellent sealing performance and prevent SF6 gas leakage from external environment impact. Its optimized spring operating mechanism uses direct-acting chain primary drive and multi-tripping system to greatly improve working reliability and stability; the inner and outer expansion chain structure for main circuit contact reduces contact resistance and temperature rise, making it maintenance-free. Compared with ZW20-12, it adds over-current protection and spring energy storage indicator, equipped with aviation socket for secondary circuit electrical connection to match intelligent controllers. It can break and close load current and short-circuit current of 10kV power system, suitable for substations, industrial and mining enterprises, and power grid sites requiring frequent operation, it has great recloser function and meets distribution automation requirements, with rated current of 630A and 1000A and mechanical endurance up to 10000 times.