10 kVA 208/120 V Three-Phase Online UPS Comparison
Compact three-phase UPS systems are widely deployed in healthcare, education, retail, and distributed IT environments requiring reliable online power protection, efficient operation, and manageable installation footprint. The Xtreme Power E91 10 kVA and the Eaton 9355 10 kVA are online double-conversion UPS systems designed for 208/120 V three-phase applications.
Both platforms provide robust double-conversion power protection and integrated maintenance bypass capability. However, key differences exist in usable output capacity, operating efficiency, physical footprint, system weight, runtime performance, and standard warranty coverage.
The E91 10 kVA delivers full-rated 10 kW output at unity power factor, higher operating efficiency, longer usable runtime at matched load, and a significantly smaller and lighter chassis. The Eaton 9355 provides comparable topology and scalability but with reduced usable output at 9 kW and a larger, heavier cabinet.
For facilities prioritizing maximum usable capacity, compact footprint, and simplified ownership, the E91 10 kVA provides a more efficient and space-optimized solution.
Learn more about the Xtreme Power E91 Series
https://xpcc.com/products/e91/
Key Differentiators at a Glance
- Full 10 kVA / 10 kW usable output (unity power factor)
• Higher operating efficiency
• Significantly smaller UPS footprint
• Lighter system weight
• Longer usable runtime at matched load
• Factory start-up included as standard
• Longer standard electronics warranty
10 kVA Three-Phase UPS Feature Comparison
208/120 V Applications
| Feature | Xtreme Power E91 10 kVA | Eaton 9355 10 kVA | Notes / Considerations |
| Rated Capacity | 10 kVA / 10 kW | 10 kVA / 9 kW | Full usable output with unity power factor |
| UPS Topology | Online double conversion | Online double conversion | Comparable premium protection |
| Efficiency (Online) | 93% | 91% | Higher efficiency reduces energy and cooling load |
| Maintenance Bypass | Standard (integrated) | Standard (integrated) | Both include integrated bypass |
| Size (W × D × H) | 9.9 × 26.3 × 32.3 in | 12 × 33.5 × 32.2 in | Significantly smaller footprint |
| Weight (with battery) | 315 lb | 373 lb | Lighter system simplifies installation |
| Internal Runtime | 11 min @ 10 kW | 8 min @ 9 kW | More usable runtime at higher real load |
| Runtime Expansion | External battery cabinets | External battery cabinets | Comparable scalability |
| Warranty (Electronics) | 2 years | 1-year parts | Longer standard coverage |
| Start-up & Labor | Factory start-up included | Start-up optional; 90-day labor | More comprehensive standard coverage |
| TAA Compliance | TAA compliant | TAA compliant | Eligible for U.S. federal procurement |
Download the Printable Comparison
Download the Xtreme Power E91 10 kVA vs Eaton 9355 comparison PDF
Ideal for engineering submittals, bid reviews, and procurement evaluations.
https://xpcc.com/wp-content/uploads/Xtreme-E91-10k-Eaton-9355-Comparison.pdf
Where the E91 10 kVA Excels
- Facilities requiring full 10 kW usable output
• Installations with limited floor space
• Deployments seeking higher operating efficiency
• Projects requiring lighter equipment for placement
• Applications needing longer runtime at matched load
• Specifications requiring longer standard electronics warranty
• Federal projects requiring TAA compliance
When the Eaton 9355 May Be a Fit
- Facilities standardized on Eaton infrastructure
• Installations aligned with existing 9355 deployments
• Sites using established Eaton service programs
Who Should Choose Which?
Choose the Xtreme Power E91 10 kVA if you need:
- Full 10 kW usable capacity
• Smaller, lighter UPS footprint
• Higher operating efficiency
• Longer internal runtime at load
• Factory start-up included
• Longer standard electronics warranty
Choose the Eaton 9355 if you need:
- Alignment with existing Eaton UPS deployments
• Standardization with 9355 infrastructure
• Eaton service ecosystem continuity
Compare E91 10 kVA to Other Compact 3-Phase UPS Alternatives
Evaluating compact three-phase UPS platforms or planning multi-site standardization?
View all E91 Series comparisons:
https://xpcc.com/e91-ups-comparisons/
Plan With Confidence
Xtreme Power Conversion supports specification development, runtime planning, and three-phase UPS deployment for healthcare, education, retail, and distributed IT environments.
(800) 582-4524
sales@xpcc.com