WATTMETER VERIFICATION DEVICE Russian patent published in 1997 - IPC

FIELD: high-frequency AC wattmeters operating at power factors from zero to unity. SUBSTANCE: two AC voltage signals are shaped for verifying values of AC voltage and current at any power factor ($$$); these signals are proportional to rated currents and voltages and their product approaches that of AC voltage by AC current; with these signals acting on power measuring transducer, thermal converters can operate at temperature equal to that caused by AC current and voltage signals. Operation of device is ensured due to introduction of two detectors 9, 10, two adders 11, 12, two analog-to-digital converters 13, 14, and computer 18. EFFECT: improved speed and accuracy of verification at power factors lower than unity. 2 dwg