DDS2-electronic single-phase power meter used advanced ultra-low-power solid-state integrated circuits technology and SMT and hot air reflow Process design and manufacture, applied metering frequency of 50 Hz AC Single-phase watt-hour. All of its properties are in line with all the technical requirements in the IEC1036 and GB/T17215-2002 standard 1.0 -- Single Phase. The precision basically can not be affected by frequency, temperature, voltage, high harmonics, and the location of installation is arbitrary. After a piece of product sale out from the factory, it did not need any adjustment, extended test cycle, thus significantly reducing the electricity sector testing and meter calibration, reliability than other similar products have improved markedly.