The standby INTERNET550SER UPS system provides reliable battery backup and AC power protection against blackouts, brownouts, overvoltages, surges and line noise that can damage valuable electronics or destroy data. The eight-outlet 120V battery backup is ideal protection for your home office, media center or professional kiosk, security and small-business phone applications that rely on a DB9 serial port for remote notification of site power and UPS operating status information.Backup support allows you to work through short power failures and gives you enough time to safely save files and shut down your system in case of a prolonged blackout. Backup time varies according to load, but the INTERNET550SER should keep an energy-efficient desktop computer with small LCD monitor powered as long as 16 minutes. During normal operation, incoming utility power keeps the replaceable internal battery fully charged, so backup power will always be available.Four 5-15R outlets provide battery backup and surge protection for your computer, monitor and other crucial components. The other four 5-15R outlets provide surge suppression only for printers, speakers and other desktop equipment regarded as non-essential during a blackout. A high >98% line mode efficiency rating reduces BTU emissions, energy consumption and, ultimately, your energy costs.A 316-joule surge suppression rating protects connected components from the harmful effects of power surges. Dual network data line surge suppression jacks protect a wired peripheral from dangerous surges on a single 10/100Base-T or dial-up network connection.This DB9 port connects the INTERNET550SER to a computer running Tripp Lite's free downloadable PowerAlert software to enable safe unattended file saves and system shutdown in case of a prolonged power failure. DB9 cable is included.Various electromagnetic and radio sources found in virtually every home and business can cause disruptive interference on the AC line. Known as EMI (electromagnetic interference) and RFI (radio frequency interference), this line noise is a common cause of performance problems and can lead to incremental hardware damage, data corruption and audio/video transmission problems. The INTERNET550SER incorporates technology that filters out disruptive line noise so that it won't affect your equipment.The UPS remains silent in both line and battery backup modes. The alarm sounds only to warn you of a low battery or fault condition. A front-panel green LED indicates line/battery mode status, overloads and low/replace battery alert.The space-saving ABS housing fits on a desktop, shelf or anywhere else convenient to your workstation or home theater. Keyhole mounting tabs on the rear allow easy wall-mount installation. The five-foot power cord with NEMA 5-15P plug connects to any compatible AC outlet.