Vertiv Liebert UPS systems: choosing the right model
This hub brings together the full Vertiv Liebert uninterruptible power supply (UPS) lineup carried by UPSPLUSBATTERY. It is built for buyers who are specifying and sizing a UPS to purchase — whether you are protecting a single edge device, a network closet, or a rack of servers. The range spans two distinct topologies and a wide power band, so it covers everything from a small 500 VA desktop unit up to a 20,000 VA / 20,000 W rack system.
Liebert sits in Vertiv's professional and data-centre UPS portfolio. The PSI5 family is line-interactive and aimed at workstations, point-of-sale, networking gear and small server loads. The GXT3, GXT5 and ITA2 families are online double-conversion systems for mission-critical IT, medical, telecom and industrial loads that need zero-transfer, fully conditioned power. Every Liebert UPS in this range outputs a pure sine wave.
Models in this range
Specifications below are drawn from the products in this collection. If the list is long, the table shows the representative models across each family — see the full range below for every variant and availability.
How to choose
Size by watts, not just VA
A UPS carries two ratings: volt-amps (VA) and watts (W). Your real load is measured in watts, so add up the wattage of the equipment you plan to plug in and choose a model whose watt rating comfortably exceeds it — aim to load the UPS to roughly 60–80% of its watt rating to leave headroom. In this range the PSI5 models run a power factor around 0.9 (for example 1500 VA = 1350 W), while the GXT5 and ITA2 online systems are unity power factor (VA = W), which gives you more usable watts per VA on larger loads.
Set your runtime expectation
Runtime depends on how heavily the UPS is loaded. The table shows half-load and full-load figures from the product specs: the lighter you load a unit, the longer it runs. If you need more than the internal battery provides, choose a model marked extended-runtime capable — the PSI5-1500 and all the GXT/ITA2 online units accept external battery cabinets for longer hold-up.
Line-interactive vs online double-conversion
The PSI5 (line-interactive) uses automatic voltage regulation to correct over- and under-voltage and switches to battery only when the utility fails — ideal, cost-effective protection for workstations, networking and small servers. The GXT3 / GXT5 / ITA2 (online double-conversion) continuously rebuilds the output waveform and delivers power with zero transfer time and full isolation from utility disturbances — the right choice for servers, storage, medical and other mission-critical loads.
Rack vs tower
Tower/rack convertible PSI5 and GXT5 units suit offices and closets that may later move into a rack. The ITA2 and 20 kVA GXT5 are rackmount (5U and up) for data-centre and equipment-room installs. Confirm depth and rail kit against your enclosure before ordering.
Why this series
- Pure sine wave output on every model — safe for active-PFC power supplies and sensitive electronics.
- Two topologies, one lineup — line-interactive PSI5 for cost-effective protection, online GXT/ITA2 for mission-critical loads.
- Wide power band — 500 VA / 450 W up to 20,000 VA / 20,000 W.
- Network management — SNMP/network cards across the range for remote monitoring and shutdown.
- Extended runtime — external battery support on the larger PSI5 and all GXT/ITA2 models.
Warranty, Canadian shipping & support
Per the product specifications, the line-interactive PSI5 models carry a 5-year warranty, and the online GXT3, GXT5 and ITA2 systems carry a 2-year warranty (extended coverage available from Vertiv). All units in this hub ship from our Canadian warehouse with Canadian support — no cross-border customs delays or surprise duties.
Replacement batteries & brand resources
Already own a Liebert UPS and need a replacement battery instead of a new system? See our Vertiv Liebert replacement batteries hub, or browse everything Vertiv Liebert on the Vertiv Liebert brand page.
Frequently asked questions
What is the difference between the PSI5 and the GXT/ITA2 Liebert systems?
The PSI5 is line-interactive — it regulates voltage and switches to battery on a utility failure, which is excellent value for workstations and small server loads. The GXT3, GXT5 and ITA2 are online double-conversion, continuously conditioning power with zero transfer time for mission-critical equipment.
How big a UPS do I need?
Total the wattage of the equipment you will protect and pick a model whose watt rating exceeds it with headroom (aim for 60–80% loading). Watts, not VA, is the binding limit for most modern IT loads.
Can I add more runtime?
Yes — the PSI5-1500 and all GXT3, GXT5 and ITA2 models in this range are extended-runtime capable and accept external battery cabinets for longer hold-up times.
Can these mount in a rack?
The PSI5 and GXT5 convertible models install in either tower or rack orientation; the ITA2 and 20 kVA GXT5 are rackmount (5U and up). Check unit depth and rail kits against your enclosure before ordering.
Do they output a pure sine wave?
Yes. Every Vertiv Liebert UPS in this range delivers pure sine wave output, which is required for equipment with active power-factor-corrected power supplies.
UPSPLUSBATTERY is an authorized Canadian reseller of genuine Vertiv Liebert UPS systems; Vertiv, Liebert and model names are trademarks of their respective owners.