... you high quality DC current 2.suitable ... advantages:1. We are 53 years 100% state-owned company, rich experience, ... /current constant (could be manually switched)AC inputvoltage rangeAC 220C, 380V, 400V, ... to userReliabilityHigh, running 24 hours a day, for sapphire crystal growth ... very lowProtectionsComplete, Phase loss, input under voltage, overvoltage, output under-voltage, overcurrent, overheat, ...