... .3% F.S.Min unit: uA,mV. ZW series DC Power Meter/Coloumeter--2011 ZW8 Flat typeZW8 flip type Features: ... 1) True effective measure: voltage, current, active power, reactive power, power factor, frequency, Kwh, etc. Total 28 electrical parameters; PT ... analog output 4-20mA for voltage, current, active power, reactive power, frequency power factor etc., set freely.6) RS232 or RS485 ...