Vertiv Liebert UPS: how to choose between EXS, ITA2, and APM by capacity and application

July 31, 2026 4 min read By Noxtel

The Liebert family from Vertiv covers virtually the entire range of three-phase UPSs for data centers and critical applications. The three most consulted series — EXS, ITA2, and APM — address different needs, and choosing between them depends on the power range, the load profile, and the scalability model the site requires.

This guide summarizes the technical differences, the power ranges, and the typical use scenarios for each series. The goal is to help sizing without having to review each individual datasheet.

Liebert EXS: the transformerless UPS from 10-80 kVA

The EXS series is a three-phase, double-conversion UPS, transformerless, with three-level IGBT. Its power range runs from 10 to 80 kVA per unit, with the option to configure parallel units up to 240 kVA. It is the entry-level option for small and medium data centers, and for applications requiring high efficiency without the complexity of a modular UPS.

Relevant specifications of the EXS series:

Efficiency: up to 96.3% in double conversion; up to 99% in ECO mode.
Output power factor: 1.0 (real power equals apparent power).
Topology: transformerless double conversion, three-level IGBT.
Density: compact design for 19-inch racks or floor installation.
Monitoring: compatible with Vertiv LIFE Services and Vertiv Trellis.

When to choose EXS: data centers from 10-80 kVA with predictable loads, where efficiency is prioritized without requiring internal modularity. It is common in edge sites, telecommunications rooms, and small corporate data centers.

Liebert ITA2: the compact UPS from 1-40 kVA

The ITA2 series covers the 1 to 40 kVA range in single-phase and three-phase versions. It is Vertiv’s most versatile line for distributed applications: network cabinets, small server racks, control rooms, and sites where space is limited.

ITA2 is designed to be installed in a 19-inch rack, with models ranging from 1 kVA (1U height) to 40 kVA (floor configuration). Efficiency reaches up to 95% in double conversion and 98% in ECO mode.

When to choose ITA2: small IT cabinets, distributed computer rooms, applications where per-rack density is low (3-8 kW) and where local service availability is key. It is a solid option for the Mexican SME market and corporates with multiple sites.

Liebert APM: the hot-swappable modular UPS from 200-600 kVA

The APM series is Vertiv’s modular three-phase UPS for medium and large data centers. Its range runs from 200 to 600 kVA per unit, with hot-swappable 25 or 50 kVA power blocks. The modular architecture allows scaling capacity without interruption and maintaining N+1 redundancy within the same cabinet. It is Vertiv’s reference for architectures that require high availability with gradual growth.

Relevant specifications of the APM series:

Efficiency: up to 97% in double conversion; up to 99% in ECO mode.
Output power factor: 0.9 (legacy) or 1.0 depending on version.
Modularity: hot-swappable power blocks of 25 or 50 kVA, without interruption.
N+1 or N+n redundancy integrable at the factory.
Compatibility with Vertiv Trellis and LIFE Services for remote monitoring.

When to choose APM: data centers from 200-600 kVA with growth plans, where modularity and redundancy are critical. It is a strong option for medium corporate sites, colocation data centers, and Tier III applications.

Summary table of the three series

For an informed decision:

Range 1-40 kVA, distributed cabinets: ITA2.
Range 10-80 kVA, small data centers: EXS.
Range 200-600 kVA, medium data centers with growth: APM (hot-swappable modular).
More than 600 kVA: APM in parallel or higher (NXL, EXL S1).
Maximum efficiency in double conversion: APM and EXS compete closely; APM has a slight edge.
Unity power factor: EXS and APM recent version. ITA2 depends on the model.
Hot-swappable modularity: APM (25/50 kVA blocks). EXS and ITA2 are fixed units (they can be paralleled, but not modular).

What no Liebert covers

The three series share the Vertiv monitoring platform and integration with Trellis and LIFE Services, which is one of Vertiv’s strongest sales arguments. But no series includes PDU, cooling, or DCIM software in the same package — those components come from complementary brands within the Vertiv portfolio (Geist for PDU, Liebert for cooling, Avocent for KVM).

Do you need help with Vertiv solutions?

At Noxtel we specialize in the design, supply, installation, and preventive maintenance of critical infrastructure for Data Centers. If you are comparing equipment, need to size a project, or require certified technical support for Vertiv solutions, our engineering team is ready to help.

📞 Contact us today and schedule an advisory session with the Noxtel team.