Abstract: Differences between the fixed metering path and the temporary reference test path may introduce additional amplitude and phase deviations during on-site calibration of revenue energy meters. A three-phase calibration model considering additional series resistance and equivalent phase deviation is established, and a software compensation method based on circuit-parameter identification and measurement-reference-point conversion is proposed. A Python phasor/time-domain simulation shows that small series resistance has limited influence, whereas equivalent phase deviation is more sensitive, especially at low power factor. At PF=0.8 and an equivalent phase deviation of 0.020°, the additional calibration error is 0.026226% and is reduced to -0.001311% after compensation.