This on-line double-conversion UPS system maintains perfect output by converting AC input to DC, then reconverting UPS output to fully regulated sine wave AC. Constant on-line operation isolates sensitive equipment from power problems on the AC line. The SmartOnline SU1500XLCD provides the highest level of power protection and battery backup for education, healthcare, military, government and other mission-critical IT applications where space is limited, but premium power reliability is essential.