Abstract. An experimental setup for measuring low and ultra-low electrical resistances is presented, method of performing measurements of samples resistance is described. The measuring method is based on the known principle of amperemeter-voltmeter. The novelty of the setup is the use of special gaskets made of highly oriented anisotropic pyrographite and installed between the current leads, measuring electrodes, and the sample under study. As a result, the contact electrical resistance at the interface "measuring electrode-test sample" is diminished, and parasitic thermopower is reduced to a negligible value. Along with expansion of the dynamic range of the setup in the area of low resistances, the measurement accuracy is improved up to 10 m. Results of measurements of the electrical resistivity of graphite rings used as heating elements of the high-temperature blackbody model of BB3500YY type are presented. An estimation of measurement error is given.

Keywords: electrical resistance, pyrographite, measurement

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