... performance, Strong isolation, Anti-Vibration.Performance CharacteristicsHigh-precision measure three-phase voltage,three-phase current,active power,reactive power ,apparent power,power factor ,frequency ... degreePower factor0.5 degreeFrequecy±0.02Hz Signal InputMode of connectionsingle-phase ,three-phase three-wire,three-phase four-wireRated voltageAC57.7V ,AC 100V,AC220V,AC380VRated currentAC1A ...