Application of DMM Linearity to dc Volt Traceability

The high linearity and stability of modern top-level digital multimeters (DMM) can be exploited to measure voltage ratios with very low uncertainty by making two separate absolute voltage measurements. We developed an integrated approach to apply commercial multimeters as voltage ratio standards for the dissemination of the volt over a wide range of values, based on a JAVS as primary ratio standard and DMMs as secondary standards. The DMM characterized in linearity can find application in top level calibration laboratories, where it can replace the Kelvin-Varley divider in calibration of meters. Moreover, we developed a GPIB interfaced voltage divider that allows the fully automatic calibration in dc voltage of generators