... certificate 3. with many type of socket Digital energy saving power meter socketitem no: JL-PM2000 Refresh Frequency: ... time3. over load and under protection4.display PF, Amp, Voltage, Hz, VA, hours, on off, watt KWH, ... , you will understand more:Functions:1. AC voltage: 90~150V AC/60Hz or 160~280V AC ... Amperage: 0~65A7.Power factor: 0~100%Parameters:1. Voltage: 90~150V AC, 60Hz ; 160~280V AC, 50Hz; ...