Realisation at IEN of a new automatic instrument for calibration of high value resistors

摘要

In this paper a metrological and electronic description of a new apparatus, that together with a dc calibrator and a DMM represents a measurement system for calibration of high value resistors in the range (100 k(OMEGA))/(10 T(OMEGA)), is reported. Inside the apparatus there are, in particular, a switching system for the resistors under calibration, four standard resistors with another switching system for their selection and a set of resistive components that, selected in a proper way, provide a guard voltage for the whole measurement circuit.