Using of AC-DC Voltage Transfer Standard Without Current Shunt in Calibration of Digital Ammeter

The presented paper considers the possibility of applying the AC-DC transfer standard based on the sensor of the root mean square alternating voltage for calibrating a precision digital ammeter. The study made an assumption about the possibility of using the AC-DC voltage transfer difference values as the AC-DC current transfer difference to correct the final measurement result. The relevant technical peculiarities of the well-known Fluke 792A instrument for comparing alternating and direct voltage are highlighted. The rigorous review of the features of two setups (applying a precision shunt and without its use) made it possible to construct an analytical model for further analysis. The nature of the shift of Fluke 792A voltage characteristic depending on the frequency was determined with help of mathematical modeling. To verify the assumption, an experiment was performed using the two specified setups. The difference in the obtained results did not exceed the expanded uncertainty.