Vertiv Liebert PSI5 UPS - 1000VA 900W 120V 1U Rack Mount Line-Interactive AVR

The Vertiv Liebert PSI5 UPS delivers reliable, business-ready power protection in a compact 1U form factor. Specifically designed for school labs, home offices, and small data closets, this 1000VA/900W unit provides clean, regulated power to protect sensitive electronics—from computers and networking gear to audio-visual equipment and critical servers. With a line-interactive AVR topology, it automatically corrects voltage fluctuations without pulling precious battery power, helping you minimize downtime, extend equipment life, and maintain productivity during outages or irregular mains conditions. The 0.9 power factor maximizes the usable energy delivered to connected devices, allowing you to run more equipment on a single UPS without sacrificing protection or performance.

Whether you’re safeguarding a small server, a network switch, a workstation, or a classroom multimedia setup, the PSI5 is engineered for dependable, easy-to-manage power protection. Its rack-mountable profile makes it ideal for shared IT closets, music studios, and educational institutions where space is at a premium. The unit’s intelligent design helps mitigate common power disturbances such as surges, brownouts, sags, and disruptive electrical noise—preserving data integrity and avoiding costly downtime. With straightforward audible and visual indicators, you can monitor status at a glance and respond quickly to events. In environments where uptime matters, the PSI5 delivers fast, seamless protection that keeps your systems running smoothly even when the power grid falters.

Beyond basic protection, the Liebert PSI5 is built to be durable and easily serviced. Its front-accessible battery compartment and simple maintenance workflow reduce downtime during battery replacements, while the robust construction ensures resilience in demanding environments. This UPS is designed to integrate into existing rack infrastructures with minimal disruption, empowering IT staff, educators, and office teams to focus on their core work without worrying about power-related interruptions. The combination of capacity, efficiency, and space-saving design makes the PSI5 a practical, long-term investment for protecting valuable devices and preserving critical data across various settings.

• Compact 1U rack-mount design saves valuable rack space while delivering 1000 VA / 900 W of protected capacity for essential equipment.
• Line-Interactive AVR topology with automatic voltage regulation maintains stable output during voltage fluctuations, reducing battery wear and extending runtime for protected devices.
• 0.9 power factor maximizes usable energy, allowing more devices to be protected by a single unit and improving overall efficiency.
• Protects connected devices from outages, surges, brownouts, and electrical noise, helping to safeguard data, hardware, and uptime in classrooms, offices, and home labs.
• User-friendly management and installation with clear front-panel indicators and straightforward compatibility with standard rack systems, ideal for quick deployments and easy maintenance.

Technical Details of Vertiv Liebert PSI5 UPS

• Model: Liebert PSI5 1kVA UPS
• Capacity: 1000 VA / 900 W
• Output Voltage: 120 V
• Input Voltage: 120 V nominal (voltage regulation supported by AVR)
• Topology: Line-Interactive AVR
• Form Factor: 1U Rack-Mount
• Power Factor: 0.9
• Protection: Battery-backed power protection with surge suppression to guard against power events
• Display/Indicators: Front-panel status indicators for quick status checks
• Management: Supports standard connectivity for monitoring and safe shutdown (USB/serial/network options available on model variations)
• Operating Environment: Typical data-center and office-friendly operating range for temperature and humidity (consult product manual for exact specs)

How to install Vertiv Liebert PSI5 UPS

• Plan the installation by identifying a stable, ventilated rack location with adequate clearance for cooling and maintenance access. Ensure the UPS is mounted in a vertical orientation with proper airflow and away from moisture or excessive dust.
• Install the 1U rack-mount rails and secure the UPS to the rack using the included hardware. Verify that the unit is level and firmly anchored to prevent vibration or movement during operation.
• Connect the UPS to a grounded AC outlet using a heavy-duty power cord appropriate for 120 V operation. Avoid using extension cords for the primary input connection to maintain proper protection and performance.
• Power up the UPS and allow it to perform a brief battery conditioning cycle if recommended by the manual. This helps calibrate the battery for accurate runtime estimates and reliable protection from the first use.
• Connect protected devices to the UPS’s surge and battery outlets. Prioritize critical equipment—such as network switches, servers, and workstations—to maximize uptime during outages. For devices requiring synchronized shutdown, connect the management interface cable as recommended and configure the monitoring software accordingly.
• If your setup includes management software or a network management card, install and configure the appropriate drivers or modules to enable monitored status, alerting, and safe shutdown procedures. Validate communication between the UPS and connected devices to ensure proper signaling in the event of a power event.
• Test the protection scenario by simulating a brief outage or by manually switching to battery mode from the front panel. Confirm that connected devices remain powered and that status indicators reflect the change. Re-charge the battery fully after testing and during normal operation to maintain readiness.
• Document the installation and keep the user manual handy for routine maintenance, battery replacement intervals, and any firmware or software updates that may enhance performance or compatibility with your equipment.

Frequently asked questions

• Q: What does 0.9 power factor mean for my setup?
  A: A 0.9 power factor means the UPS delivers 90% of its apparent power as usable real power to the connected devices. This allows you to protect more equipment with the same unit and improves energy efficiency, especially in environments with compact rack deployments where every watt of real power matters.
• Q: Is the Vertiv Liebert PSI5 suitable for office and classroom use?
  A: Yes. The PSI5 is designed for use in schools, homes, and small offices. Its compact 1U rack footprint, reliable AVR protection, and straightforward management make it a practical choice for protecting computers, networking gear, AV equipment, and other critical devices in non-enterprise environments.
• Q: How does the AVR feature help during power disturbances?
  A: Automatic Voltage Regulation maintains consistent output voltage when incoming mains fluctuate within a moderate range. This reduces wear on connected equipment, minimizes unexpected reboots, and extends battery life by avoiding unnecessary battery discharge during voltage sags or minor surges.
• Q: Can I monitor the UPS status from a computer?
  A: Many Liebert PSI5 variants offer USB and serial (and sometimes network) management options to monitor voltage, load, battery capacity, and event history. Check the specific model’s accessories to confirm available interfaces and software compatibility for remote monitoring and safe shutdown.
• Q: What kind of runtime can I expect?
  A: Runtime depends on the load connected to the UPS. At lighter loads, you’ll typically experience longer runtime; under heavier critical loads, runtime decreases accordingly. For planning, estimate based on the UPS rating (900 W) and the total wattage of devices you intend to protect, and always account for battery age and environmental conditions.