NRC-NIST intercomparison of calibration systems for current transducers with a voltage output at power frequencies

A number of international comparisons of current transformer calibrations at power frequencies were conducted in the past. However, all comparisons were done with a secondary current output of 5 A. This inter-comparison of current transformer calibration systems for power frequencies between the National Research Council of Canada and the National Institute of Standards and Technology, USA, was done with a primary current range of 100 A and a nonstandard secondary output signal of voltage range of 10 V. The comparison was implemented with a transfer standard consisting of a commercial current-comparator-based transimpedance amplifier, based on a development at the National Research Council of Canada modified to make the output voltage adjustable in magnitude and phase within a range of +-1 percent. The results indicate that there are no significant differences in the overall accuracy of calibration systems for current transducers with a voltage output at power frequencies in each laboratory.