M90S-4S Modular UPS – 6–12kW Scalable Single-Phase UPS with N+1 Redundancy
6–12 kW | 208/120V or 240/120V | Modular Online UPS
Modular single-phase UPS platform engineered for centralized power protection, scalable capacity growth, and N+1 redundancy in commercial, industrial, and distributed infrastructure environments.
6–12 kW · 208/120V or 240/120V · Modular Online Double-Conversion UPS · N+1
M90S-4S scalable modular single-phase UPS
The M90S-4S is the scalable tier of the M90S modular family — a 4-slot online double-conversion UPS that grows from 6 kW to 12 kW on single-phase power. It is built for facilities outgrowing rack UPS but still within single-phase infrastructure, using hot-swappable 6 kW power modules and modular batteries for N+1 redundancy and phased growth. Unity output power factor (kVA = kW), a 5.7″ graphic display, integral maintenance bypass, plug-in L14-30P deployment, and configurable output receptacle panels. TAA compliant; UL-1778 (TUV) / cUL listed.
Scalable power beyond rack UPS
The M90S-4S introduces true modular scalability within single-phase infrastructure — for facilities where power requirements are growing beyond rack UPS capability but remain single-phase. Built on a 4-slot architecture using 6 kW power modules, it scales from 6 kW to 12 kW and supports N+1 redundancy, runtime expansion, and phased deployment within a single platform. Capacity can be added incrementally as load grows, so UPS sizing aligns to actual requirements while preserving flexibility for future expansion.
What the M90S-4S delivers
Add a hot-swappable 6 kW power module to move from 6 to 12 kW within the same frame — capacity aligns to actual load instead of oversizing or replacing the UPS.
Configure redundant power and battery modules for N+1 within one system, up to 6 kW (one load module plus one redundant) — the availability of multiple UPS without the footprint, wiring, or management overhead. The 12 kW build uses both power slots for capacity and is non-redundant.
Unity PF (kVA = kW) delivers full usable watts with best-in-class efficiency — up to 98% ECO mode — lowering energy cost and heat output, with no need to oversize for a derated power factor.
A factory-installed L14-30P line cord (6 kW) enables deployment without immediate electrical work, and up to two configurable output receptacle panels deliver C19, 5-20R, L6-20R/L6-30R, and L14-30R distribution from the UPS frame.
A 5.7-inch graphic display shows system status and alarms, and each power module carries its own LCD for module-level detail and redundancy state — faster diagnostics and service.
A manual maintenance bypass transfers the critical load to utility power for service without dropping it, and output distribution inside the frame removes external connection components — reducing installation cost.
The scalable modular tier
The M90S-4S sits between the entry M90S-2S and the core M90S-6S — a scalable centralized platform for single-phase infrastructure, typically deployed in electrical rooms supporting distributed infrastructure, where multiple separate UPS would otherwise be required, or in facilities transitioning toward a centralized UPS design.
Choose the M90S-4S for single-phase load growing through 6–12 kW with redundancy headroom; step down to the M90S-2S for a fixed 6 kW entry system, up to the M90S-6S for 6–24 kW, or to the hardwired M90S-12S for 6–48 kW.
Modular vs traditional UPS
Traditional fixed-capacity UPS must be oversized up front or replaced as infrastructure grows. A modular platform lets capacity, redundancy, and runtime scale incrementally within one system.
| Modular (M90S-4S) | Traditional UPS | |
|---|---|---|
| Capacity scaling | Add a 6 kW module to 12 kW | Fixed capacity |
| Redundancy | Built-in N+1 | Requires multiple systems |
| Runtime | Modular battery expansion | Less flexible |
| Maintenance | Hot-swap, module-level service | Full-system service |
| Lifecycle | Extend capacity in place | Replace at capacity |
Two capacities in one enclosure
| Model | Capacity | Power modules | Max charge current | Input |
|---|---|---|---|---|
| M90S-4S6K | 6 kVA / 6 kW | 1 × 6 kW | 4 A | L14-30P cord or hardwired |
| M90S-4S12K | 12 kVA / 12 kW | 2 × 6 kW | 8 A | Hardwired (2PH+N+G) |
One 4-slot enclosure (17.4 × 33.7 × 33 in, 130 lb) holds 2 universal slots (power or battery) plus 2 battery-only slots — a maximum of two 6 kW power modules (12 kW); an optional BC7 cabinet (17.4 × 33.7 × 45.5 in) adds 7 battery slots. For N+1, add one power module beyond the load, so redundancy is available up to 6 kW (one load module plus one redundant); at 12 kW both power slots carry load, so the 12 kW configuration is a maximum-capacity, non-redundant build.
Runtime by load and battery module count
Runtime in minutes by kW configuration and number of installed battery modules, grouped by the battery-cabinet stage required (the 4S enclosure holds 3 internal battery slots in the 6 kW config; each BC7 cabinet adds 7). The stepped line tracks the four-slot enclosure sharing power and battery slots: the internal-battery maximum falls as more power modules are installed (3 modules at 6 kW, 2 at 12 kW), with each BC7 cabinet adding seven slots beyond it. An asterisk marks runtimes that need an additional power module for recharge; a dash means that module count does not apply to the configuration.
| 4S UPS | 4S UPS + 1 BC7 | 4S UPS + 2 BC7 | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Battery modules | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
| 6 kW | 9 | 22 | 35 | 50 | 66 | 82 | 99 | 113 | 124* | 133* | 148* | 163* | 179* | 194* | 209* |
| 12 kW | — | 9 | 15 | 22 | 28 | 35 | 43 | 50 | 58 | 66 | 74 | 82 | 90 | 99 | 106 |
Estimated minutes; values vary with battery age and site conditions. A maximum of eight battery modules is supported per power module; an asterisk (*) marks runtimes that require an additional power module for battery recharge. For longer runtimes or configurations beyond 15 modules, contact Xtreme Power engineering at (800) 582-4524 or sales@xpcc.com.
Rack deployment
The M90S-4S supports rack-based deployment with integrated mounting hardware and serviceable module access, installing in standard equipment racks while keeping power and battery modules accessible. Watch a short rack-installation overview:
Where the M90S-4S is deployed
The M90S-4S is deployed across single-phase environments where capacity is growing and redundancy matters — telecommunications infrastructure, network distribution rooms, industrial automation, broadcast environments, and commercial infrastructure — typically where load is expected to grow over time, runtime exceeds rack-UPS capability, multiple separate UPS are becoming difficult to manage, or a three-phase upgrade is not practical.
M90S-4S specifications
| Topology | Modular online double-conversion |
| Capacity | 6 kVA / 6 kW and 12 kVA / 12 kW (unity PF, kVA = kW). N+1 redundancy up to 6 kW (one load module plus one redundant); 12 kW is a maximum-capacity, non-redundant build. |
| Input | 120/208V or 120/240V, 50/60 Hz auto-sensing (2PH+N+G); range 152–269 VAC (L-L), 40–70 Hz |
| Output | 120/208V or 120/240V, 50/60 Hz ±0.1 Hz (2PH+N) |
| Efficiency / THD | Up to 98% ECO mode, 93% online mode; ≤2% (linear), ≤3% (non-linear) |
| Overload | 100–110% for 30 min; 110–130% for 5 min; 130–150% for 10 s; >150% for 200 ms |
| Battery system | Nominal ±96 VDC; max charging 4 A (6 kW) / 8 A (12 kW), adjustable |
| Power module | 16.3 × 24 × 5.2 in, 38 lb |
| Battery module | 16.3 × 24 × 5.2 in, 107 lb |
| UPS enclosure | 17.4 × 33.7 × 33 in, 130 lb; 4 slots (2 universal + 2 battery-only) |
| BC7 battery cabinet | 17.4 × 33.7 × 45.5 in, 162 lb; 7 additional battery slots |
| Output distribution | Terminal blocks and/or up to two configurable receptacle panels (C19, 5-15/5-20R, L6-20/L6-30R, L14-30R) |
| Input options | L14-30P line cord (6 kVA); receptacle panels (2 max); extended battery cabinet; 5-year extended warranty |
| Display | 5.7″ graphic LCD; per-power-module LCD |
| Communications | RS-232, USB, dry contacts, EPO; (2) intelligent slots (Web/SNMP, Relay, Modbus) |
| Environment | 0–40°C (32–104°F); altitude 5,200 ft; audible noise <58 dBA at 1 m |
| Approvals | UL-1778 (TUV), cUL, FCC Class A, RoHS; TAA compliant |
| Warranty | 3 years electronics, 3 years battery (USA and Canada) |
Documents and related links
Plan your M90S-4S deployment
Talk to an Xtreme Power specialist about module configuration, N+1 redundancy, runtime sizing with BC7 battery cabinets, receptacle-panel selection, and phased growth from 6 to 12 kW.
| CAPACITY | Power Rating | 6kVA/6kW | 12kVA/12kW |
| INPUT | Voltage / frequency nominal | 120/208V or 120/240V & 50/60Hz auto-sensing (2PH+N+G) | |
| Voltage / frequency range | 152-269VAC* (L-L) / 40–70Hz | ||
| OUTPUT | Voltage & Frequency | 120/208V or 120/240V & 50/60Hz ± 0.1Hz; (2PH+N) | |
| Efficiency / THD (full load) | Up to 98% ECO mode, 93% online mode / ≤2% (Linear load); ≤3% (Non linear load) | ||
| Overload capacity | 100% – 110% for 30 min; 110% – 130% for 5min; 130% – 150% for 10s; > 150% for 200ms | ||
| BATTERY SYSTEM | Nominal voltage | +/-96V | |
| Max charging (adjustable) | 4A | 8A | |
| MODULE DIMENSION | Power module | 16.3”W x 24”D x 5.2”H / 38 lbs | |
| & WEIGHT | Battery module | 16.3”W x 24”D x 5.2”H / 107 lbs | |
| SYSTEM ENCLOSURE | Dimensions & Weight | UPS 17.4”W x 33.7”D x 33”H & 130 lbs / BC7 17.4”W x 33.7”D x 45.5”H & 162 lbs | |
| Maximum Capacity | 12kVA | ||
| Enclosure Capacity | 4 slots including 2 universal slots + 2 battery only slots | ||
| Optional Battery Enclosure | 7 slots for additional battery modules | ||
| Output Connections | Terminal blocks and/or up to 2 receptacle panels | ||
| ENVIRONMENT | Temperature | 0–40°C (32–104°F) | |
| Altitude | 5,200 ft above sea level | ||
| Audible noise | < 58dBA at 1m | ||
| APPROVALS | UL-1778 (TUV), cUL, FCC A, RoHS | ||
| WARRANTY | 3 year electronics, 3 year battery (USA and Canada) | ||
| COMMUNICATIONS INTERFACE | RS-232, USB, Dry Contacts, EPO, (2) intelligent slot for optional cards (Web/SNMP, Relay, Modbus) | ||
| INCLUDED IN BOX | User manual, USB cable, RS-232 cable, ViewPower Software, anchor brackets | ||
| AVAILABLE OPTIONS | L14-30P line cord (6kVA), receptacle panels (2 max), extended battery cabinet, 5 year extended warranty | ||
