Accurate measurement of electric energy is related to the immediate interests of the general electric power enterprise and users. If there is an incorrect wiring event of the electric energy metering device, it will cause metering mistake and even may cause economic disputes. In order to correct metering mistakes in most cases, the first is to determine the correction coefficient, then calculate the electricity quantity correction. Because of the correction coefficient is often associated with the power factor angle, it is probably real-time changing, which will bring misalignment or inconvenience of calculation. Based on the active and reactive electricity of the error wiring three-phase three-wire static multifunctional electric energy meter, this paper deduces the expression of actual active electricity by means of vector analysis, what makes the calculation of the active electricity mistake more accurate and efficient.