EKSS800 is a high-efficiency, high-performance double conversion, pure-online three-phase input and three-phase output UPS product (uninterruptible power supply), which provides the perfect power protection solution scheme and has solved such power supply problems as the power interruption, the high voltage of the commercial electricity, the low voltage of the commercial electricity, the instantaneous drop of voltage, damped oscillation, high-voltage pulse, surge voltage, harmonic distortion, clutter interference and frequency fluctuations, so that the products are widely used in the computer equipment, the communications equipment and other types of control devices. Therefore the EKSS800 series UPS is the best choice used in such multiple industries or fields as the telecommunications, finance, transportation, government, manufacturing and energy resources.