The Xtreme Power Conversion M90S-6S, configured for 18 kW usable output, and the Vertiv Liebert APS AS6D0NCXGNNXLKB are modular, true online, double-conversion UPS systems designed to protect mission-critical IT, network, and edge-infrastructure loads.
While both platforms provide scalable modular architectures and hot-swappable components, the M90S-6S delivers full 18 kW output at unity power factor, longer internal runtime with base batteries, and integrated service features, making it better suited for higher-density deployments and improved operational flexibility.
18 kW Modular Online UPS Comparison
| Feature | XTREME POWER M90S-6S (18 kW) | Vertiv Liebert APS AS6D0NCXGNNXLKB | XPCC Advantage |
| Usable Output Capacity | 18 kVA / 18 kW (unity PF) | 20 kVA / 18 kW (0.9 PF) | Full 18 kW delivered without oversizing kVA |
| Topology | Online Double Conversion | Online Double Conversion | Equivalent protection |
| Internal Runtime (Full Load, base battery) | ~9 min @ 18 kW | ~5 min @ 18 kW | Significantly longer internal runtime |
| Modular Expandability | Scales to 24 kVA / 24 kW | Scales to 20 kVA (N+1) | Higher maximum scalable capacity |
| Maintenance Bypass | Standard, integrated | Optional external bypass cabinet | Lower install cost and space savings |
| Rack / Tower Mounting | Rack kit (M90S-RMK) or tower | Rack / tower convertible | Equivalent deployment flexibility |
| Display & Diagnostics | Chassis LCD + module-level displays | Removable chassis LCD | More granular local diagnostics |
| Certifications & Compliance | UL, cUL, TAA Compliant | UL, cUL (TAA varies by configuration) | Consistent positioning for regulated markets |
| Warranty Coverage | 3 years (electronics & batteries) | 2-year limited warranty | Longer standard coverage reduces lifecycle risk |
Printable Comparison PDF
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Where the M90S-6S (18 kW) Excels
- Deployments requiring full 18 kW usable output at unity power factor
- Applications prioritizing longer internal runtime without EBMs
- Facilities planning future growth beyond 20 kVA
- Projects seeking integrated maintenance bypass to reduce install complexity
- Regulated environments requiring clear, consistent TAA compliance
When Vertiv Liebert APS May Be a Fit
- Vertiv-standardized environments
- Architectures designed around external bypass cabinets
- Deployments where scaling beyond 20 kVA is not required
Who Should Choose Which
Choose Xtreme Power Conversion M90S-6S if you need:
- Full 18 kW usable output without kVA oversizing
- Longer baseline runtime with internal batteries
- Greater scalability headroom within the same platform
- Integrated service features to simplify installation and maintenance
- Longer standard warranty on electronics and batteries
Choose Vertiv Liebert APS if you need:
- Alignment with an existing Vertiv APS ecosystem
- A solution designed around incremental modular scaling
- External bypass as part of a predefined system architecture
Ideal Applications
- Edge and enterprise data-center environments
- IDF / MDF closets with high power density
- Healthcare and laboratory facilities
- Government and education infrastructure
- Modular UPS standardization initiatives
Plan with Confidence
Request a Quote
Speak with an Xtreme Power Conversion specialist to configure the right M90S-6S 18 kW modular architecture for your load, runtime, and compliance requirements.
Xtreme Power Conversion
Phone: (800) 582-4524
Email: sales@xpcc.com