A PXI Modules-Based Voltage Injection System for AC Resistors Calibration

Wheatstone bridges are frequently used to calibrate AC resistors. The balance of the AC Whetstone Bridge can be ensured by injecting an in-phase and quadrature voltage as a function of the input voltage of the bridge. PXI modules are usually used as voltage injection systems (phase and quadrature), especially for automated bridges. In this paper, a comparison is presented between different high-performance PXI modules, where these devices are used as voltage injection systems for AC resistor calibration. Here three PXI modules are compared: Applicos-AWG22, EMX-1434, and NI-4461, with experimental measurements performed up to 20 kHz on these modules. The results are presented with several comparisons to get an insight into the performances of the generators that are suitable for voltage injection systems, as well as, for calibration of AC resistors. The results are then validated by using these PXI modules in a Wheatstone bridge used at LNE to calibrate AC resistors.