This series products, compared with other types, have the advantages of big capacity, high efficiency, small waveform deformation, smooth voltage regulation, wide range of load, the ability of resisting instant overload, long-term continuous operation, manual & automatic control method, protective function of over-voltage, short-circuit and mechanical transmission failure, little volume and weight, easy and convenient use, reliable operation,etc.. This series can be used as high quality alternative voltage stabilizing supply for industry, agriculture, transportation, military, postal offices, railway, scientific research institutes, precision machine tools, industrial production line, medical facilties, architectural engineering equipment and testing equipment, air condition, broadcast and TV stations and hotels.