CCE intercomparison of AC-DC transfer standards

A worldwide comparison is described covering both AC voltage and AC current measurements in the frequency range from 40 Hz to 1 MHz. Results are consistent within 10-20 p.p.m. at low voltage and frequency, but differ by up to 100 ppm at high voltage and frequency. For currents of tens of milliamperes the results are consistent within 40 ppm.<
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