This is a tool used to calculate accuracy of energy meters. Energy meters are devices that are used to measure the electricity consumption in terms of KWH (Kilo Watt Hour), where 1 KWH is the amount of energy consumed by 1KW load in 1 hour. To calculate the accuracy of energy meter, connect supply and load with energy meter with proper connections. You can use either AVO Meter (Ampere, volt, ohm) or Power Meter (Watt Meter) for measuring the load applied to meter.
*************************** AVO Meter **********************************
Use voltage terminal of meter to measure the voltage of supply applied to meter and use current terminal of meter to measure the amount of amperes flowing through meters with connected Load, note down both these values in app.
*************************** Watt Meter **********************************
In case of Watt meter, connect meter across load with proper connections and note down the value of KW from meter.

There are two types of energy meters available: Electromechanical and Digital
In case of ElectroMechanical meter, observe its revolutions, wait for marker on dial of meter to be in front and start stopwatch, stop the stopwatch after required number of revolutions when marker is again in front.
In case of Digital/Static Meter, observe impulses of LED in front of meter which says Imp/KWH. Start stopwatch when LED blinks, count required number of blinks of LED and stop the stopwatch.

Enter value of "n" (number of revolutions/impulses) observed
Enter value of "To" (Time observed), built in stopwatch can also be used for this purpose
Enter Value of "N" (Meter Constant) which could be obtained from front panel of meter written with a unit of "Rev/KWH" (Electromechanical Meter) or "Imp/KWH" (Digital Meter)
Enter Value of "V", "I" in case of AVO Meter and Value of "P" in case of Watt Meter
Press "Calculate" Button for calculation of accuracy of energy meter

************** Power Factor *******************
In Portrait Orientation, default value of P.F used is 0.9.
In Landscape Orientation, P.F value could be entered by user, otherwise 0.9 default value would be used.
Value of Power Factor used depends upon type of load applied on the meter. Normal lighting load or electric header mostly have P.F 0.9.
In case of Induction motor value of P.F used should be 0.8.