P91-6K vs Vertiv Liebert GXT5-6000RT208
The Xtreme Power P91-6K and Vertiv Liebert GXT5-6000RT208 are both 6 kVA / 6 kW unity-PF online double-conversion VRLA rack UPS in a 4U-with-EBP footprint. Both deliver full 6 kW with hot-swap batteries; the P91-6K differentiates on shallower depth, a 3U battery cabinet option, a programmable graphical display, and longer runtime.
What the P91-6K brings
- Shallower chassis depth (up to 2.5 in vs the Vertiv)
- 3U battery cabinet option (2x battery in 50% more rack space)
- Intuitive graphical LCD with programming options
- 2x baseline runtime with the 2U external battery pack
- Full 3-year UPS and battery warranty
Side-by-side specifications
| Specification | Xtreme Power P91-6K + BPXR2U240A | Vertiv Liebert GXT5-6000RT208 | Advantage |
|---|---|---|---|
| Capacity | 6000 VA / 6000 W (unity PF) | 6000 VA / 6000 W (unity PF) | Both unity power factor |
| Topology | Online double-conversion | Online double-conversion | Both online double-conversion |
| Footprint (with EBP) | 17.3 × 23.6 × 7.0 in (4U) | 16.9 × 25.6 × 6.8 in (4U) | P91 – up to 2.5 in shallower depth |
| Battery chemistry | VRLA | VRLA | Both valve-regulated lead-acid |
| Battery cabinet options | 2U and 3U | 2U only | P91 – 3U option (2x battery, +50% space) |
| Display | LCD – graphical, programmable | LCD – limited programming | P91 – richer graphical interface |
| Hot-swappable batteries | Yes | Yes | Both hot-swappable |
| Runtime | 8 min @ 4.8 kW (with 2U EBP) | 4 min @ 4.8 kW | P91 – 2x runtime |
| Warranty | 3-yr electronics & battery | 3-yr electronics & battery | Both full 3-year UPS + battery |
Specifications from Xtreme Power’s supplied P91-6K vs Vertiv GXT5-6000RT208 comparison; based on publicly available manufacturer data. Both are 4U-with-EBP 6 kW unity-PF online VRLA systems; the runtime figures are quoted at 4.8 kW with the 2U external battery pack. The Vertiv chassis is marginally narrower and shorter, while the P91 is up to 2.5 in shallower in depth.
Choosing between them
Both deliver full 6 kW unity-PF online VRLA protection with hot-swap batteries and matching 3-year UPS-and-battery warranties. The P91-6K leads on chassis depth, battery cabinet flexibility (2U and 3U), display programmability, and runtime (2x with the 2U EBP); the Vertiv is marginally narrower and shorter and fits Vertiv-standardized environments.
Choose the P91-6K + BPXR2U240A if you need
- Depth-constrained racks needing a shallower chassis
- Cost- and footprint-efficient runtime via the 3U battery module
- Longer baseline runtime at full load
- Deployments benefiting from a programmable graphical display
The Liebert GXT5-6000RT208 may fit if you need
- Standardization on the Vertiv Liebert ecosystem
- Racks favoring a marginally narrower / shorter chassis
- Sites aligned to existing Vertiv runtime infrastructure
Related comparisons
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