P91-5K vs APC Smart-UPS SRT5KRMXLT
The Xtreme Power P91-5K and APC Smart-UPS SRT5KRMXLT are both 5 kVA online double-conversion VRLA rack UPS for servers, network, and telecom infrastructure. The P91-5K delivers higher usable watts and longer baseline runtime; the APC emphasizes a compact integrated 3U chassis.
What the P91-5K brings
- Higher usable watt capacity (5 kW vs 4.8 kW)
- Longer full-load runtime (7 min vs 3.5 min)
- Expandable runtime with external battery packs
- Flexible rack or tower deployment
- TAA compliance and 3-year battery coverage
Side-by-side specifications
| Specification | Xtreme Power P91-5K | APC Smart-UPS SRT5KRMXLT | Advantage |
|---|---|---|---|
| Capacity | 5 kVA / 5 kW | 5 kVA / 4.8 kW | P91 – higher usable watts |
| UPS topology | Online double-conversion | Online double-conversion | Equivalent protection |
| Runtime (full load) | 7 min @ 5 kW | 3.5 min @ 4.8 kW | P91 – longer runtime |
| Battery technology | Sealed lead-acid (VRLA) | Sealed lead-acid (VRLA) | Comparable architecture |
| External battery packs | Yes | Yes | Runtime expansion supported |
| Rack height | 4U (2U UPS + 2U battery) | 3U | APC is more compact (3U vs 4U) |
| Form factor | Rack / tower | Rack / tower | Flexible deployment |
| Input / output voltage | 208/220/230/240 V | 208/220/230/240 V | Comparable |
| Warranty | 3-yr UPS / 3-yr battery | 3-yr UPS / 2-yr battery | P91 – longer battery coverage |
| Compliance | UL1778, CE, FCC, RoHS, TAA | UL1778, IEC 62040-2, RoHS | P91 – TAA for federal procurement |
Specifications from Xtreme Power’s supplied P91-5K vs APC SRT5KRMXLT comparison; based on publicly available manufacturer data. The P91-5K runtime reflects the system with a BPXR2U240A battery pack. APC is more compact (3U) while the P91 trades height for runtime.
Choosing between them
Both deliver online VRLA protection with external-pack expansion. The P91-5K leads on usable watts, runtime, warranty, and TAA; the APC SRT5KRMXLT is more compact (3U vs 4U) and fits APC-standardized environments.
Choose the P91-5K if you need
- Higher usable watt output (5 kW vs 4.8 kW)
- Longer baseline runtime at full load
- TAA compliance for government / regulated procurement
- Flexible rack or tower deployment
The Smart-UPS SRT5KRMXLT may fit if you need
- The most compact footprint (3U integrated chassis)
- Standardization on the APC Smart-UPS ecosystem
- Non-TAA commercial deployments
Related comparisons
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