Vertiv Liebert PSI5 UPS - 1100VA Line Interactive, Rackmount, with NICVertiv Liebert PSI5 UPS 1100VA Line Interactive Rackmount with NIC The Vertiv Liebert PSI5 1100VA UPS is purpose built to protect critical IT equipment in small to mid sized data centers, network closets, and office server rooms. With a robust 1100 VA 990 W capacity, a 120 VAC input output, and a reliable line interactive topology, this unit delivers dependable power protection against outages, sags, surges, and harmonic disturbances. Designed for