The establishment of DC power meter calibration system at China Electric Power Research Institute

The establishment of a DC power meter calibration system using a DC current comparator and a synchronous sampling technique at China Electric Power Research Institute (CEPRI) is described. Measurements can be made at DC voltages ranging from 10mV to 1000V, and DC currents from 10mA to 500A. The system features a synchronous voltage/current sampling system and a multi-ratio DC current comparator. The uncertainty of the DC power meter calibration system is estimated to be not more than 120 μW/W. A comparison with another DC power meter calibration system at the National Institute of Metrology China (NIMC) is discussed.