For satisfying the local survey of low voltage area, a multi-function equipment for low voltage area identified is developed and manufactured based on power frequency load transmission and quasi-synchronization sampling technology. High-speed A/D sampling and DSP process technology are used in association with embedded system based on MSW8532B2. The measurement, sampling, storage and transmission of data information is realized, which consists of the customer archive attribution of low voltage area, network topology, customer electricity phase and sequence, the load balance degree of Three-phase, distortion coefficient and harmonic analysis of power grid voltage.