Yangzhou new concept electric co., ltd. Has independently developed 72.5kv intelligent phase selection (synchronous) hv permanent-magnetic vacuum circuit breaker (hereinafter referred to as "intelligent circuit breaker") at world advanced level by integrating domestic and foreign advanced technologies, adopting the new design concept and applying hi-tech means. With permanent-magnetic mechanism, vacuum arc extinction, integrated sensor and arm+dsp processor, this intelligent circuit breaker self-adapts to own parameters and the impact of environment, thus being the first choice for the realization of power grid intelligentization. This product conforms to iec60298, gb3906-2006, gb/t 11022-1999, dl/t 593-2006, gb 1984-2003 standards, etc.  major technical parameters are shown below: Rated voltage 72.5kv Rated current 1600/2000/2500a Rated frequency 50hz Rated short-duration (1 min) power frequency withstand voltage 160kv Rated short-circuit breaking current 31.5ka Thermal stability current(4s) 31.5ka Rated lightning impluse withstand voltage(to earth/break) 350kv Dynamic stability current(peak value) 80ka Rated short-circuit current breaking times 20 times Operating time 40-60ms Operating voltage Ac/dc220v Mechanical service life >10000 times Main circuit resistance