ZN12 series of indoor high voltage vacuum circuit breaker is with rated voltage of 40.5kV,three-three phase A.C.50(60) Hz indoor high voltage switch equipment.The structure of this kind of circuit breaker is simple but with strong breaking capability;it is suitable for application in the mining industry,substations and power transmission and distribution systems for controlling and protecting the switch.Especially suitable foe the industry which requires frequently operations like metallurgy fields,electric arc steel plant to control and protect the equipment.This kind of vacuum circuit breaker can be assembled with truck which can be suitable for many kinds of switchgear such as JYN1,GBC etc 1.The operating mechanism is introduced the technique of operating mechanism from Siemens 3AF vacuum circuit breaker,the operating mechanism is integrated with vacuum circuit breaker,with characteristics of short transmission routes,less chains and high transmission efficiency. 2.This operating mechanism adopts spring type,it can be operated by AC or DC,also can be operated by manual.1. Ambient air temperature: -5~+40 and the average temperature should not exceed +35 in 24h. 2. Install and use indoors. Altitude above sea level for operation site should not exceed 2000M. 3. Relative humidity should not exceed 50% at max temperature +40. Higher relative humidity is allowed at lower temperature. Ex. 90% at +20. But in view of the temperature change, it is possible that moderate dews will produce casually. 4. Installation gradient not exceed 5. 5. Install in the places without fierce vibration and shock and the sites insufficient to erode the electrical components. 6. Any specific requirement, consult with manufactory.