Evaluation of an Automatic High Resistance Bridge

摘要

An overview of the resistance measurement systems presently in use at the National Measurement Institute (NMI) was previously presented [1]. Recently, NMI acquired a new MI-6000B Automatic High Resistance Bridge, which is capable of measuring resistances ranging from 1 k(OMEGA) up to 1 T(OMEGA) [2]. This bridge complements our existing MI-6010B Automatic Direct Current Comparator Bridge which covers the resistance range from 1 m(OMEGA) up to 10 k(OMEGA). As anticipated, the MI-6000B bridge has become one of the main workhorses at the NMI as it is fully automatic and can achieve better measurement uncertainties than the existing Wheatstone bridge. Before this bridge was implemented in the calibration service, corrections and the uncertainties of the bridge in the range of 10 k(OMEGA) up to 1 G(OMEGA) were evaluated. The bridge system, the theory of its operation, the evaluation method and results are described.