Evaluation of the effects of leakage current in the calibration of standard resistors between two dc resistance bridges and a digital sampling impedance bridge

This article discusses calibrations results of standard resistors performed with two commercially available equipment and a digital sampling impedance bridge developed at Inmetro. One of the commercial bridges uses the current comparison method and the other the potentiometric method with a binary voltage divider. Calibration was performed with standard resistors of 10 kΩ and 100 kΩ with significant leakage current. This study showed divergent results between each methodology. A specific methodology was used to estimate the leakage resistance of these resistors. This study contributes to establish criteria for correction and/or inclusion of uncertainty components in resistors calibrated in these methodologies.