Active power is the power which is actually consumed or utilized by the AC circuit, It is the actual outcomes of Electrical circuits Measured in KiloWatt. Power is calculated with the Help of three Wattmeter Method. Wattmeter is an instrument consist of Two coils current coil and Potential coil The current coil having low resistance is connected in series with the load so that it carries the load current. The potential coil having the resistance is connected across the load and carries the current proportional to the potential difference.