Inductive voltage dividers comparison with a vector voltmeter

A setup for calibration of inductive voltage dividers, based on a vector voltmeter with very high common-mode-rejection-ratio (CMRR), is described. The voltmeter is built with a differential amplifier and a lock-in board, both enclosed in a guard, completely battery-operated and interfaced with optical fiber links. An implementation with commercial instrumentation is tested and first results are shown.