Vertiv Liebert PSI5 Lithium-ion 3000VA Short Depth 3U Rack/tower UPS 120 - PSI5-3000SRT120LI

Vertiv PSI5-3000SRT120LI Lithium-Ion 3000VA Short-Depth Rack/Tower UPS

Overview

The Vertiv PSI5-3000SRT120LI is a 3000VA / 2700W line-interactive UPS built around a lithium-ion battery chemistry — the right pick when you need extended runtime, reduced weight relative to lead-acid equivalents, and the ability to swap batteries without taking the system offline. At 16.92 inches deep in a 3U chassis, it fits rack enclosures where conventional deep UPS units physically won't. It ships with rack power protection features that matter in production environments: pure sinewave output, automatic voltage regulation across a 75–146VAC input window, and ten output receptacles covering both standard NEMA 5-20R loads and a twist-lock L5-30R for higher-draw equipment.

If you're speccing UPS for a surveillance head-end, a network closet, or an edge compute rack — places where runtime, footprint, and power quality all matter simultaneously — the PSI5-3000SRT120LI is worth evaluating carefully. Vertiv's broader Vertiv power and thermal lineup covers everything from single-phase UPS to modular three-phase infrastructure if your requirements scale up.

Key Features

• 3000VA / 2700W Lithium-Ion Power Stage: Lithium-ion chemistry delivers meaningfully longer cycle life than VRLA alternatives and holds capacity better over time. For a rack that runs 24/7, that translates to fewer battery replacement cycles and lower total cost over the system's lifespan — relevant if you're managing a multi-site deployment where battery logistics are a real operational cost.
• Pure Sinewave Output on Battery: When utility power drops and the UPS switches to battery, it produces a clean sinusoidal waveform rather than the stepped approximation that modified-sinewave units output. Active PFC power supplies — common in servers, NVRs, and enterprise networking gear — require true sinewave to operate correctly. Running them on modified sinewave risks instability or equipment damage. This spec isn't optional if your load includes modern switching supplies.
• Line-Interactive Topology with AVR (75–146VAC Range): The automatic voltage regulation corrects both sags (down to 75VAC) and surges (up to 146VAC) without switching to battery. In environments with chronic undervoltage — older building wiring, shared circuits with heavy loads — this means the battery isn't being cycled on every fluctuation. That preserves battery life and keeps runtime available for actual outages.
• 98.1% Efficiency: Operating at 0.981 efficiency in normal mode keeps heat dissipation low and operating costs in check. On a unit drawing at significant load, even fractional efficiency gains compound across thousands of operating hours — meaningful in a data closet where cooling is already a concern.
• Short-Depth 3U Chassis (16.92 in deep): Standard rack UPS units often run 20–24 inches deep, which conflicts with shallower wall-mount or telco-style enclosures. At 16.92 inches, the PSI5-3000SRT120LI fits racks where depth is constrained — edge sites, IDF closets, or compact surveillance equipment rooms — without requiring a rail extension or a deeper cabinet.
• Front-Access Hot-Swappable Battery Kits: Battery replacement happens from the front panel without pulling the unit from the rack or powering down the load. In a production environment where any maintenance window has a cost, this matters. Lithium-ion chemistry also means the replacement interval is longer, but when that interval arrives, the service impact is minimal.
• 10-Outlet Output (9 × NEMA 5-20R + 1 × L5-30R): Nine standard 5-20R receptacles handle most rack PDU and equipment connections. The single L5-30R twist-lock provides a dedicated high-current output for equipment that requires it — useful when your rack includes a high-draw appliance alongside standard compute or networking gear.
• Rotatable LCD Display: The control panel rotates to remain legible whether the unit is installed in rack or tower orientation. Small detail, but in a mixed-install environment where some units stand vertical, not having to crane your neck to read status is a real convenience.
• EPO Connector + Optional IntelliSlot UNITY Card: The emergency power-off connector integrates with building safety systems. The optional network management card (Liebert IntelliSlot UNITY) adds SNMP and web-based monitoring — essential for remote visibility in any managed infrastructure. Without the card, USB provides local communication only.

Integration and Compatibility

The PSI5-3000SRT120LI connects to a host system via USB for local UPS communication. For networked monitoring and shutdown management, the optional Liebert IntelliSlot UNITY card enables SNMP and web management — the interface most enterprise environments expect for infrastructure monitoring integration. The ten-outlet configuration and L5-30P input cord make it straightforward to integrate with standard rack PDU setups. Output voltage is 120VAC default with user-selectable alternatives (100, 110, 115, 125VAC), providing compatibility flexibility across load types. Certifications include UL 1778, c-UL-us, UN38.3 (lithium battery transport), NOM, and FCC Part 15 Class B — the standard commercial listings for North American deployment.

Frequently Asked Questions

Q: Does the PSI5-3000SRT120LI use lithium-ion or lead-acid batteries?

A: Lithium-ion. The PSI5-3000SRT120LI's lithium-ion battery chemistry provides longer cycle life and better capacity retention over time compared to traditional VRLA lead-acid alternatives, which is a key reason this model is positioned for environments where battery replacement logistics and total cost of ownership matter.

Q: Can I replace the batteries without powering down the connected equipment?

A: Yes. The PSI5-3000SRT120LI supports front-access hot-swappable battery kits, meaning battery replacement is performed from the front panel while the UPS continues supplying power to the load. No rack pull or load shutdown is required.

Q: Does this UPS produce a pure sinewave output when on battery?

A: Yes. The PSI5-3000SRT120LI outputs a pure sinewave on battery, which is required for compatibility with active PFC power supplies commonly found in servers, NVRs, and enterprise networking equipment. Modified-sinewave UPS units can cause instability or damage with these load types.

Q: What input plug and output receptacles does the PSI5-3000SRT120LI use?

A: Input is an L5-30P twist-lock plug. Output includes nine NEMA 5-20R receptacles and one L5-30R twist-lock receptacle, giving you ten protected outlets total. Output voltage defaults to 120VAC and is user-selectable to 100, 110, 115, or 125VAC.

Q: Does the PSI5-3000SRT120LI include network management (SNMP) capability out of the box?

A: Not by default. USB communication is included standard. SNMP and web-based management require the optional Liebert IntelliSlot UNITY communications card, which installs in the unit's interface slot. Without this card, remote monitoring is not available.

Q: Will the PSI5-3000SRT120LI fit in a shallow-depth rack enclosure?

A: At 16.92 inches deep in a 3U form factor, it is significantly shallower than most comparably rated UPS units, which typically run 20–24 inches. It is designed for rack cabinets and enclosures where depth is constrained, including wall-mount and edge-site installations.

Jerry Tildsen

The spec that sells the PSI5-3000SRT120LI in competitive evaluations is the 16.92-inch depth combined with the lithium-ion chemistry — that pairing is uncommon at 3000VA. Most 3kVA units either have the short depth or the Li-ion, not both. If you're fitting this into a 24-inch-depth rack at an edge site and you need the battery to last across a multi-year service cycle without a truck roll, the PSI5-3000SRT120LI closes that gap.

Technical Highlights:

• 98.1% Operating Efficiency: At near-unity efficiency, thermal output in the rack is minimal. On a unit this size, that's a meaningful difference in a space where cooling is already constrained — edge closets, compact IDF rooms, or any enclosure without dedicated airflow.
• 75–146VAC Input Window (AVR): That's a 71-volt swing the unit absorbs without touching the battery. In older facilities with chronic undervoltage or shared circuits running compressors and lighting, this range keeps the battery out of the protection loop for everything except genuine outages — preserving both runtime and battery cycle count.
• Pure Sinewave + 2700W Continuous Rating: 2700W at unity power factor. If your rack load includes active PFC supplies — which is most modern server and network hardware — this is the floor requirement. Any modified-sinewave unit creates compatibility risk with that equipment, and the efficiency penalty compounds over a 24/7 operating cycle.

Deployment Considerations:

• The SNMP/web management capability requires purchasing the optional Liebert IntelliSlot UNITY card separately — the base unit ships with USB only. If remote monitoring and graceful shutdown integration are in scope, budget for that card and spec it into the initial PO. Retrofitting it later at a remote site costs a truck roll.
• Input is L5-30P, which requires a matching circuit or adapter. Verify your panel and PDU wiring before deploying — this isn't a straight NEMA 5-20 drop-in at 3kVA. The L5-30 circuit requirement should be confirmed with the electrician during site prep, not discovered during rack commissioning.

This unit is a strong fit for surveillance head-ends and edge compute sites where the rack is 24 inches deep or shallower, the load is 2kW+ of mixed servers and network gear, and the maintenance model requires minimum on-site service time. The hot-swap front-access batteries make it particularly practical in unmanned or infrequently staffed locations.