Phase shift correction of reference sampling multimeter for electronic transformer calibration

The calibration of electronic transformer (ET) with digital output can be realized using reference digital voltage multimeter(DVM)with synchronized sampling. However, there are time related errors of DVM which affect the result of phase displacement of ET under calibration. Such errors include the trigger latency, bandwidth limitation and aperture time of the DVM. This paper estimates the errors and makes a correction to the calibration result. The accuracy of the correction is verified using an arbitrary waveform generator (AWG) with dual synchronized channels with satisfactory results.