Abstract: During the operation of electric power metering devices, the phasor diagram serves as an effective means to intuitively display their wiring configurations, voltage and current phases, and phase angles. Currently, during on-site inspections, personnel typically employ devices such as phase volt-ampere meters and electricity usage analyzers to connect to the voltage and current terminals at the terminal block of the electric energy meter. By measuring voltage, current, and phase angles, these instruments calculate and generate phasor diagrams, which are then used to determine the meter's wiring configuration and operational accuracy. This method has some shortcomings, such as the need to open the meter's terminal cover to connect to the corresponding terminals, and the accuracy of the wiring at the meter terminals does not fully reflect the meter's metering status. This paper proposes a method to achieve the direct plotting of phasor diagrams by acquiring data such as the electric energy meter's operation status word, real-time voltage and current, power factor, and power direction. This approach aims to address the deficiencies of existing inspection instruments and improve the efficiency of on-site operations.