1Accuracy: 1% +/- 2 words2Range: AC voltage: AC 250-450V; The measuring range 250-450V, and it can be used in grid , photovoltaic and inverter current; 250-450V only can use for 380V; AC Current:AC 0-1000A, the current resolution is 001A .; Frequence: 450Hz - 650Hz; Factor: 000-100PF3Electric : 0-450000W,the electric resolution is 01W when measure electric between 0-99999W,otherwise the electric resolution is 1WElectric Energy: 0-99999kwh,the display of electric energy resolution is 001kwh when measure electric engery between 0-99999kwh,the display of electric energy resolution is 01kwh when measure electric engery between 10000-99999kwh and the display of electric energy resolution is 1kwh when measure electric engery larger than 99999kwh4Speed: 2 times per second5Installation: Din-RailApplication : 1. Connect the measure voltage to the 1 and 2 terminal2. Connections of meter with internal current transformer as graph 1. Make the wire through the hole in the meter and the direction chose arbitrarily.3. Connections of meter with external current transformer as graph 2. Make the wire through the hole in the meter, and connect the two wires of the secondary transformer to the 3 and 4 terminal.4. When on, the meter display the measure parameters.5. When on, you can press the button of last for 5 seconds, then the electric energy will to be zero and start to cumulate when release the button. And when off, the meter can save the value of electric energy and go on cumulating data when the meter -on .Attention: The meter can only use for measure 45-65Hz AC city electricity.Size: 54x80x64mmcolour: as shownMaterial: PlasticPackage Contents:1 x Watt-hour meterOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.