Helko E. van den Brom, Erik F. Dierikx, and Leendert Jol, "Sampling Ratio Bridge for Impedance Measurements Down to 1 mΩ" Submitted for publication in the Proceedings of the 2012 Conference on Precision Electromagnetic Measurements, Washington, US (July 2012).
This paper describes the development of a current-driven automated sampling ratio bridge for the accurate measurement of low-ohmic impedance standards. Initial tests at 50 Hz and 1 kHz indicate that relative uncertainties of a few times 10-6 can be obtained for ratios of 10 to 100. For lower impedance values the uncertainty will increase. We demonstrated operating the bridge for AC resistance values down to 1 m.
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