1.Once Seal-Exhaust Technique 2.Free maintenance and low cost 3.favourable price and selected quality 4.short dilivery time 1mmMain Technical Data Please see the attachment. Rated voltage 12KVRated current 630ARated frequency 50HZRated short-time power frequency withstand voltage (1min) 42KVRated lightring impulse withstand voltage (1 min) 75KVRate short-circuit breaking current16/20KARate short- ...