摘要:.In view of the problem of poor error stability of the three-phase energy meter verification device under low current load, the working principle and error calculation method of the device are analyzed. The harmonics content and error data of the device under low current load before and after the installation of the isolation transformer are tested on site. And the role of the isolation transformer in suppressing the harmonics of the device is analyzed. From the harmonics content and error data of the output current of the device before and after the installation of the isolation transformer, it can be seen that the isolation transformer can effectively suppress the harmonics content of the device at the time of low current output and also improve the error stability under low current load.