... for protection and controlling, as well as inter-connection circuit breaker. It is also available in places for frequent operations. ... point,phase-t phase,phase-to-earth)kV 95*levelfrequency withstand voltageWet test (phase to earth, external insulation )kV 80*Lightning ... , filled with dry air and high pure nitrogen15Annual gas leakage rate%≤116Vacuum arc extinguish room vacuum degreeNew ex-work vacuum ...