An International Comparison of Inductive Voltage Divider Calibrations at 400 and 1000 Hz

The establishment and maintenance of the highest possible order of accuracy for the measurements of voltage ratio and phase angle are responsibilities of the national laboratories. This paper reports the results of an international comparison of a seven-decade inductive voltage divider by the United States National Bureau of Standards and the National Research Council of Canada. The calibration techniques used in each laboratory are discussed in detail, and the results of calibration at 400 and 1000 Hz are compared. The accuracies of measurements are within 0.1 ppm of input for voltage ratio and 1 (setting of dials)1/2 microradians for phase angle.