YDK1 is designed for using in the infrequency supply electricity fields and is capableof meeting more demands of reliable power-driven equipment under city power-drivenincreasing condition. It has the features of reliable performance, smallvolume, and simple operation.Features:1) Provided with such protective functions as checking two sources of voltage at the same time, protection when any one phase or one phase above experiences under- or over-voltage, guide phase2) When two sources have abnormal or faulty tripping (overload, short circuit), the controller won't send out the order to realize the protective function of reopening and closing3) Four working modes: automatic control, common source (power supply I), standby power supply (power supply II), breaking electricity (re-tripping)4) When the working mode is in the automatic control state, it has two self-throw no self-recover, self-throw, and self-recover functions: a) Self-throw non-self recover: when the device enters the working state, power supply I automatically throws into supplying electricity; when power supply I has an abnormity, it will automatically transfer to power supply II; when power supply I recovers, it doesn't transfer until power supply II has an abnormity, then it will automatically transfer to power supply I b) Self-throw and self-recover: when the device enters the working state, the common source throws into supplying electricity; when power supply has an abnormity, it will automatically transfer to standby power supply; when common power supply recovers, it will automatically recover common power supply; but when the standby power supply has an abnormity, the controller will emit an alarm sound.Specifications: 1) Rated current: 2,000 - 3,200A2) Rated working voltage: 690V3) Selection function: self-throw self-recovery, self-throw non-self-recovery, provided controller outside4) Connection voltage: 230 - 400V5) Product features: integrated transferring, reliable performance producing area:China payment:L/C, T/T