Features of Precision Phase Meters Calibration with the National Standard of Unit of the Phase Shift Angle Between Two Voltages in the Full Range of Values

High-precision phase meters are used in phase-frequency measurements. An overview of the precision phase meters calibration features with the National standard of the phase shift angle between two voltages in full range of values is given. The content of quantitative and qualitative indicators of corrections, which must be taken into account when calibrating the phase meters to achieve the highest measurement accuracy, is revealed.