DDSF1531 series single-phase electronic multi-tariff watt-hour meter is for measuring active energy of single phase 220V and 50Hz, it adopts the latest MPU tech-nology and digital energymeasurement chip of high accuracy and wide range, it has many features such as high accuracy. wide range, high stability, low power consumption and graceful appearance. Because LCD or LED and military components are used, it is characterized with long service life, free maintenance and convenient meter reading. It can measure positively and negatiovely, and has ability of anti-electricity theft and output pulse, to take convenience for detecting. It is the first selection product for implementing national time sharing electricity price policy.