Functions and Features: 1. Active power measurement. LED blinks if there is load. 2. LCD Display. Number of digit: 8 3. Volts, Accuracy: 0. 5% 4. Amps, Accuracy: 0. 5% 5. Active power VA, Accuracy: 0. 5% 6. Cumulative time 7. Cumulative Killowatt-Hour 8. Function Key: Clear kWh to zero Technical Parameters: 1. Standard: GB2099. X-1997/ GB17215-2003 2. Rated Voltage: 220V 3. Rated Frequency: 50Hz 4. Rated Current: 10A(Basic Current) - 40A(Maximum Current) 5. Accuracy: Class 1. 0 6. Meter constant: 1600imp/Kwh 7. Power Consumption: Less than 0. 6W 8. Weight: 250g 9. Size: 158*80*50MM 10. Basic operation Temp: -10--35 degree The energy usage monitor uses SOC technology(Only one chip which finish ADC, MCU and LCD Driver functions). It displays Volts, Amps, Watts, Hz, VA, Time. It can be widely used in the field such as power quality checking, Cumulative Killowatt-Hour monitoring