M90LU Modular UPS – Extended Runtime Three-Phase UPS (15–60kW, 208/120V)
15–60 kW | 208/120V Three-Phase | Modular Online Double-Conversion UPS
Modular three-phase UPS engineered for facilities requiring extended runtime, flexible battery architecture, and scalable infrastructure design.
15–60 kW · 208/120V Three-Phase · Modular Online UPS · External Battery · Extended Runtime · Unity PF
M90LU extended-runtime modular three-phase UPS
The M90LU is a scalable modular three-phase online double-conversion UPS engineered for critical loads that need very long battery runtime. It shares the M90U modular platform — 15 to 60 kW at unity power factor from hot-swappable 15 kW or 20 kW power modules — but separates the UPS from the battery system, so runtime is engineered independently of capacity and scaled with external M90-BC / M90-BOS or third-party batteries. Because the batteries sit outside it, the UPS enclosure is only 30" tall and 227 lb, and pairing it with the matching M90-BOS battery cabinet splits a complete system into two short units on casters — two moderate floor loads that can be placed apart, rather than one tall, heavy cabinet. Built for data centers, telecom, industrial, and critical infrastructure where ride-through must be designed to site requirements.
Runtime engineered independently of capacity
The M90LU is a scalable modular online double-conversion UPS designed for critical loads requiring very long battery run-times. It can be configured with fully redundant power modules — if one fails, the remaining modules smoothly take over the load — and the independent power modules are hot-swappable without risk to the critical load. By separating the UPS and battery system, the M90LU lets runtime be designed and expanded on its own, aligned to the application rather than constrained by an internal battery compartment.
Scale power and runtime separately
Unlike integrated-battery UPS, the M90LU keeps no internal batteries — runtime is delivered by external battery systems sized to the site. The platform supports Xtreme Power M90-BC and M90-BOS battery systems as well as third-party configurations, so capacity (power modules) and runtime (battery strings) scale independently. The result is finer runtime planning, simpler battery service, and infrastructure that can grow on either axis without replacing the UPS.
| Design axis | How the M90LU scales it |
|---|---|
| Capacity (kW) | Add 15 kW or 20 kW hot-swappable power modules, up to three per enclosure |
| Runtime (minutes) | Add external M90-BC battery strings — up to 8 strings (individual breakers, 4 modules per string) |
| Battery source | Xtreme Power M90-BC / M90-BOS, or third-party battery systems |
| Redundancy | Configure a redundant power module (N+1) and redundant battery strings |
What the M90LU delivers
Runtime is engineered independently of capacity and scaled with external M90-BC strings — from minutes to hours, aligned to the application.
Unity PF (kW = kVA) provides full real capacity for high-density loads — no derating of usable watts from the kVA rating.
Add 15 kW or 20 kW modules as power requirements change; modules hot-swap without risk to the critical load.
Configure a redundant power module (N+1 to 40 kW on 20 kW modules, 30 kW on 15 kW modules) plus redundant battery strings for the highest availability.
Dual- or single-input configurations and rear / side / bottom cable entry provide maximum installation flexibility.
An integrated full wrap-around maintenance bypass with static-switch interface transfers the load to utility for service, with a 5.7-in graphic LCD for status and alarms.
Capacities and module configuration
M90LU is offered in two module lines — 15 kW and 20 kW power modules — each scaling across three enclosure slots. Unity power factor means the kVA and kW ratings are equal. Runtime is configured separately through external M90-BC batteries.
| Model | Capacity | Power modules | Charge current | Redundancy |
|---|---|---|---|---|
| M90LU-15 | 15 kVA / 15 kW | 1 × 15 kW | 8 A | Single module |
| M90LU-30 | 30 kVA / 30 kW | 2 × 15 kW | 16 A | N+1 to 15 kW |
| M90LU-45 | 45 kVA / 45 kW | 3 × 15 kW | 24 A | Fully populated — non-redundant |
| M90LU-20 | 20 kVA / 20 kW | 1 × 20 kW | 8 A | Single module |
| M90LU-40 | 40 kVA / 40 kW | 2 × 20 kW | 16 A | N+1 to 20 kW |
| M90LU-60 | 60 kVA / 60 kW | 3 × 20 kW | 24 A | Fully populated — non-redundant |
The enclosure holds up to three power modules (up to 45 kW with 15 kW modules, up to 60 kW with 20 kW modules). N+1 protected capacity is one module below the fully populated rating; the 45 kW and 60 kW ratings are fully populated and non-redundant. Charge current scales with the populated module count (8 / 16 / 24 A).
Runtime by battery cabinet, modules and load
Runtime depends on which battery cabinet the M90LU is paired with. The short M90-BOS matches the UPS enclosure and holds up to twelve modules, covering standard runtimes in a two-cabinet system that stays under 30". The full-height M90-BC holds up to thirty-two modules in eight strings, for ride-through well beyond what any internal-battery system delivers. Figures are approximate minutes and assume fully formed batteries; a dash means the load is beyond the supported range for that configuration.
M90-BOS — short cabinet, up to 12 modules
| M90-BOS modules | System load (kVA = kW) | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 5 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 | |
| 2 modules | 15 | 5.4 | — | — | — | — | — | — | — | — | — | — |
| 4 modules | 34 | 15 | 8.5 | 5.4 | — | — | — | — | — | — | — | — |
| 6 modules | 55 | 24 | 15 | 9.9 | 7.3 | 5.4 | — | — | — | — | — | — |
| 8 modules | 78 | 34 | 21 | 15 | 11 | 8.5 | 6.9 | 5.4 | — | — | — | — |
| 10 modules | 100 | 44 | 27 | 19 | 15 | 11 | 9.3 | 7.7 | 6.6 | 5.4 | 4.6 | 3.9 |
| 12 modules | 115 | 55 | 34 | 24 | 18 | 15 | 12 | 9.9 | 8.5 | 7.3 | 6.4 | 5.4 |
M90-BC — full-height cabinet, up to 32 modules
| M90-BC modules | System load (kVA = kW) | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 5 | 10 | 15 | 20 | 25 | 30 | 35 | 40 | 45 | 50 | 55 | 60 | |
| 4 modules | 36 | 15 | 9 | 5 | — | — | — | — | — | — | — | — |
| 8 modules | 88 | 36 | 22 | 15 | 12 | 9 | 7 | 5 | — | — | — | — |
| 12 modules | 140 | 61 | 36 | 25 | 19 | 15 | 13 | 10 | 9 | 7 | 6 | 5 |
| 16 modules | 196 | 88 | 52 | 36 | 27 | 22 | 18 | 15 | 13 | 12 | 10 | 9 |
| 20 modules | 257 | 115 | 70 | 48 | 36 | 29 | 24 | 20 | 17 | 15 | 14 | 12 |
| 24 modules | 314 | 140 | 88 | 61 | 46 | 36 | 30 | 25 | 22 | 19 | 17 | 15 |
| 28 modules | 373 | 168 | 107 | 74 | 56 | 44 | 36 | 31 | 26 | 23 | 20 | 18 |
| 32 modules | 432 | 196 | 122 | 88 | 66 | 52 | 43 | 36 | 31 | 27 | 24 | 22 |
Runtimes are approximate and vary with battery age, temperature, and site conditions. Battery life is reduced above 30°C and capacity derates above 30°C and 5,200 ft. Contact Xtreme Power at (800) 582-4524 or sales@xpcc.com for runtime sizing and M90-BC / M90-BOS configuration.
The extended-runtime member of the M90U family
M90LU is the extended-runtime platform within the M90U family — the same modular UPS as the internal-battery M90U, configured for external batteries. It is deployed where runtime requirements exceed internal-battery capability, where centralized battery systems are preferred, or where power and runtime must scale independently. The M90U-80 and M90U-140 extend the family to higher capacities.
Current page
See the full M90U platform family.
M90LU vs the alternatives
| Compared with | How the M90LU differs |
|---|---|
| M90U (internal-battery sibling) | Same modular UPS platform. M90U uses internal batteries for compact, standard-runtime deployment; M90LU uses external batteries for extended runtime. Choose M90LU when runtime exceeds internal-battery capability or centralized batteries are preferred. |
| Traditional extended-runtime UPS | Rather than oversized internal batteries or fixed battery-cabinet configurations, the M90LU separates UPS and battery so runtime is engineered independently and expanded as needed — improving flexibility and simplifying maintenance. |
| Lithium UPS (e.g. Li90) | A modular external-VRLA approach optimized for extended runtime and battery flexibility. Choose lithium when reduced maintenance, integrated battery design, and higher energy density are the priority. |
See the lithium UPS guide for the VRLA-vs-lithium trade-off.
Replace legacy extended-runtime systems
M90LU is commonly deployed to replace legacy APC and Eaton UPS requiring extended runtime — systems needing longer ride-through than internal batteries allow, facilities transitioning to centralized battery architectures, infrastructure requiring scalable runtime and modular serviceability, and sites modernizing legacy UPS with limited runtime flexibility.
Where the M90LU is deployed
M90LU is deployed across infrastructure requiring extended runtime and scalable UPS architecture — data centers, telecom and network infrastructure, industrial systems, healthcare environments, and edge data center deployments.
Approvals and warranty
The M90LU carries UL-1778, cUL, FCC Class A, and RoHS, and is TAA compliant on select models — confirm TAA eligibility for the specific model and configuration when a regulated procurement requires it. The UPS is backed by a 2-year warranty (USA and Canada); external batteries carry their own (M90-BC / M90-BOS or third-party) terms.
M90LU specifications
| Capacity | 15 / 20 / 30 / 40 / 45 / 60 kVA = kW (unity PF), from 15 kW or 20 kW modules |
| Topology | Modular online double-conversion, three-phase |
| Input | 208Y/120V three-phase, 50/60 Hz auto-sensing; range 121–253 VAC (L-L), 40–70 Hz; dual or single input |
| Output | 208Y/120V three-phase, 50/60 Hz ±0.5 Hz; THD <2% at full load |
| Efficiency | Up to 94% online mode, up to 98% ECO mode |
| Overload | 105–110% (60 min); 110–125% (10 min); 126–150% (1 min); >150% (200 ms) |
| Redundancy | N+1 capable — protected ceiling 40 kW (20 kW modules) / 30 kW (15 kW modules); 45 kW and 60 kW fully populated, non-redundant |
| Battery | External — M90-BC / M90-BOS or third-party; ±120 VDC; up to 8 strings with individual breakers (4 hot-swappable modules per string, up to 32); charge current 8 / 16 / 24 A by module count |
| Bypass | Integrated full wrap-around maintenance bypass with static-switch interface (external maintenance bypass optional) |
| UPS enclosure | 20.3"W × 39.4"D × 30"H / 227 lb; power module 19.3"W × 29.0"D × 5.2"H (490 × 736.5 × 133 mm) / 74 lb (20 kVA), 72 lb (15 kVA) |
| M90-BC battery cabinet | 23.6"W × 43.3"D × 79.1"H / 860 lb + 85 lb per module |
| Cable entry | Rear, side, or bottom |
| Display | 5.7-in graphic LCD — status and alarms |
| Communications | RS-232, EPO, intelligent slot (Web/SNMP, Modbus), optional relay card |
| Environment | 0–40°C (32–104°F); altitude 5,200 ft; audible noise <65 dBA at 1 m |
| Options | External maintenance bypass, 480V input transformer, output distribution, external battery pack, battery temperature sensor |
| Approvals | UL-1778, cUL, FCC A, RoHS, TAA (select models) |
| Warranty | 2-year UPS (USA and Canada) |
M90LU — frequently asked questions
What is the difference between the M90LU and the M90U?
Where the battery lives. Both are the same modular platform, 15–60 kW from up to three hot-swappable 15 kW or 20 kW power modules. The M90U houses up to twelve battery modules inside the UPS enclosure, which caps runtime at what one cabinet holds. The M90LU moves the battery outside entirely, so runtime is sized to the site rather than to the cabinet. Choose the M90U when standard runtime is enough and one cabinet is simpler; choose the M90LU when the required ride-through exceeds what internal batteries deliver.
Does the third module slot add capacity or redundancy?
Either one, not both. The enclosure holds three power modules. With 20 kW modules, three populated slots give 60 kW with no redundancy, or 40 kW with the third held in reserve. With 15 kW modules the same choice gives 45 kW non-redundant or 30 kW N+1. The protected ceiling is always one module below the fully populated rating.
Should I specify 15 kW or 20 kW power modules?
The module rating sets the capacity ladder. The 20 kW line scales 20 / 40 / 60 kW; the 15 kW line scales 15 / 30 / 45 kW. The two ratings cannot be mixed in one frame, so moving between them means replacing the whole set rather than adding to it. The modules are the same parts used across the M90U, M90U-80 and M90U-140, so anything already purchased carries forward.
How does unity power factor change the comparison with other UPS?
It changes the usable watts. The M90LU is rated at unity, so kVA and kW are the same number and a 60 kVA system delivers 60 kW. A competing 60 kVA system rated at 0.9 power factor delivers 54 kW to the same load. Size on watts rather than kVA, or two systems will look equivalent on paper when they are not.
Can I use third-party batteries?
Yes. The M90LU is designed to work with the matched M90-BC and M90-BOS enclosures or with third-party battery systems, which is the point of separating the battery from the UPS. The M90-BC holds up to eight strings of four hot-swappable modules, thirty-two in total, each string on its own breaker so it can be isolated for service without dropping the others. Charge current is 8, 16 or 24 A depending on the populated module count.
What should I plan for on installation?
The UPS enclosure is compact because it holds no batteries: 20.3"W × 39.4"D × 30"H at 227 lb. The battery is the heavy part. An M90-BC cabinet is 23.6"W × 43.3"D × 79.1"H, 860 lb before modules, and adds 85 lb per battery module. Cable entry to the UPS is from the rear, side or bottom. Confirm floor loading for the battery cabinets early, since they drive the structural requirement rather than the UPS.
Documents and related links
Plan your M90LU deployment
Talk to an Xtreme Power specialist about modular UPS sizing, independent power and runtime scaling, external M90-BC / M90-BOS battery design, N+1 redundancy, dual-input integration, and APC / Eaton extended-runtime replacement for centralized facility power.