... Energy Meter single&3 phase RMS measurement for volt,amp,power.frequency,power factor,reactive power,etc. 2011--Industrial Energy Meter, digital Watt Meter ... (Wattmeter) Features: Power Supply80-260V AC/DC or 18-30V AC/DC(24V DC)Measure ... (Barbara Guo) 086-13435730867(Peter Liao) 2011--Industrial Energy Meter, digital Watt Meter(Wattmeter)