The Xtreme Power Conversion M90S-6S and the APC Symmetra LX SYA16K16P are modular, true online, double-conversion UPS systems designed to protect mission-critical single-phase loads. Both platforms support hot-swappable modules and scalable architectures.
However, the M90S-6S is an active, current-generation platform that delivers higher usable power, greater efficiency, broader scalability, and long-term availability for expansion and factory support, while the Symmetra LX is a discontinued legacy system.
18 kVA Modular UPS Comparison
| Feature | XTREME POWER M90S-6S | APC Symmetra LX (SYA16K16P) | XPCC Advantage |
| Product Status | Active production | Discontinued (Aug 26 2025) | Long-term platform availability |
| Capacity | 18 kVA / 18 kW (unity PF) | 16 kVA / 12.8 kW (0.8 PF) | ~40% more usable watt output |
| Topology | Online Double Conversion | Online Double Conversion | Equivalent protection |
| Modularity / Scalability | 6–24 kVA in 6 kVA increments (up to 18 kVA N+1) | 4–16 kVA N+1 in 4 kVA increments | Higher maximum capacity |
| Efficiency | Up to 98% (ECO) / 93% online | ~88.7% online | Lower energy cost & heat |
| Internal Runtime | Up to 9 min @ 18 kW | Up to 6 min @ 12.8 kW | Longer internal runtime |
| Maintenance Bypass | Standard | Standard | Equivalent serviceability |
| Module Slot Flexibility | Universal slots (power or battery) | Dedicated power & battery slots | Simpler expansion & sparing |
| Display | 5.7″ color LCD + module-level LCDs | Chassis-level LCD only | Improved diagnostics |
| Warranty | 3-year repair or replace | 2-year repair or replace | Longer standard warranty |
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Where the M90S-6S Excels
- Replacing discontinued Symmetra LX systems with a supported platform
- Deployments requiring full kW output (unity power factor)
- Facilities prioritizing energy efficiency and reduced cooling load
- Installations needing flexible module allocation
- Organizations planning future expansion with assured availability
When APC Symmetra LX May Still Be in Use
- Existing installations with installed spare parts
- Short-term support scenarios where no expansion is planned
- Legacy environments awaiting planned UPS refresh cycles
Who Should Choose Which
Choose Xtreme Power Conversion M90S-6S if you need:
- An active, long-term supported modular UPS platform
- Higher usable power from the same footprint
- Greater efficiency to reduce operating cost
- Simpler expansion and sparing with universal slots
- Longer warranty coverage
Choose APC Symmetra LX if you need:
- Temporary continuation of an existing legacy installation
- No requirement for future expansion or factory support
Ideal Applications
- Enterprise data-center edge environments
- Healthcare and laboratory facilities
- Industrial and manufacturing operations
- Government and education infrastructure
- Symmetra LX replacement projects
Plan with Confidence
Request a Quote
Speak with an Xtreme Power Conversion specialist to size the right M90S modular configuration and migration path from legacy systems.
Xtreme Power Conversion
Phone: (800) 582-4524
Email: sales@xpcc.com