... three-phase voltage,three-phase current,active power,reactive power ,apparent power,power factor ,frequen Description: Intelligent digital instrument be used in ... degreeFrequecy±0.02Hz Signal InputMode of connectionsingle-phase ,three-phase three-wire,three-phase four-wireRated voltageAC57.7V ,AC 100V, ... diagram 96*96 SINGLE-PHASE THREE ROW AC VOLTAGE FREQUENCY LED DIGITAL COMBINATION METER RH-UIF33