Power basics
Single-phase or three-phase UPS: where the three-phase models start
A single-phase UPS takes and delivers one phase plus neutral; a three-phase UPS takes and delivers three phases. Current three-phase ranges start small: the Vertiv Liebert ITA2 at 5 kVA, the Eaton 93PS at 8 kW, and the Eaton 9355, APC Easy UPS 3S and Eaton 93PM at 10 kVA or kW. Some makers also sell 3:1 versions, three-phase in and single-phase out, such as the Eaton 91PS.
Phases, wiring and power range by model
| Model | Phases and wiring | Power range | Status | Source |
|---|---|---|---|---|
| Vertiv Liebert ITA2 Liebert ITA2 3-phase, 5 to 40 kVA, 208 V | 3:3, 208/220 V, 4W + G | 5 to 40 kVA at 208/220 V, up to 80 kW in parallel | Current | Vertiv, Liebert ITA2 3-phase UPS page |
| Eaton 93PS 93PS, 8 to 40 kW | 93PS is 3:3; the 91PS is the 3:1 version (three-phase in, single-phase out) | 8 to 40 kW | Current | Eaton, 91PS and 93PS UPS page |
| Eaton 9355 9355, 10 to 30 kVA | Output 208/120 V or 220/127 V | 10 to 30 kVA, at 208, 220, 480 or 600 V | Current | Eaton, 9355 UPS page |
| APC Easy UPS 3S E3SUPS20KFBS (20 kVA, 208 V, internal batteries) | 3:3, 208 V or 220 V | 10 to 40 kVA (208 V and 400 V models) | Current | Schneider Electric Canada, E3SUPS20KFBS; Schneider Electric Canada, Easy UPS 3S 20 kVA 208 V (E3SUPS20KFBS) |
| APC Galaxy VS GVSUPS20KFS (20 kW, 208 V) and GVSUPS100KGS (100 kW, 480 V) | 3:3; 208 V model: 4-wire or 5-wire input, 5-wire output (3P + N + E); 480 V model: 4-wire input (3P + E) | About 10 to 150 kW, depending on voltage (208 V, 400 V and 480 V models) | Current | Schneider Electric Canada, GVSUPS20KFS; Schneider Electric Canada, GVSUPS100KGS; Schneider Electric Canada, Galaxy VS range |
| APC Symmetra PX SY40K40F (40 kW N+1, 208 V) | 3:3, 208 V; 5-wire input and output (3P + N + E) | 10 to 40 kW in the 208 V frames, and 250 or 500 kW in the large frames | Partly discontinued: December 31, 2025 (150 kW scalable to 250 kW model) | Schneider Electric Canada, SY40K40F |
| Eaton 93PM 93PM 208V (North America) | 208/120 V or 220/127 V, 4-wire input | 10 to 200 kW at 208 V and 220 V, and 50 to 250 kW at 480 V in a 250 kW frame | Current | Eaton, 93PM 208V UPS page |
| Vertiv Liebert APM2 Liebert APM2 UL, 208 V (data sheet SL-71300) | Output 208/220 V, 3-phase 3-wire + N + PE | 10 to 150 kVA/kW at 208/220 V and 20 to 600 kVA/kW at 480/415 V | Current | Vertiv, Liebert APM2 data sheet SL-71300; Vertiv Canada, Liebert APM2 UL UPS 208V |
| XPC M90U-80 M90U-80, 15 to 80 kW at 208/120 V | 208/120 V three-phase in and out | 15 to 80 kW in a single cabinet at 208/120 V | Current | XPC, M90U-80 |
| Socomec MASTERYS GP4 MASTERYS GP4, 10 to 250 kVA/kW | Output 1ph + N 230 V or 3ph + N 400 V | 10 to 250 kVA/kW | Current | Socomec, MASTERYS GP4 |
| APC Galaxy VL GVL200K500DS (200 kW scalable to 500 kW, 400/480 V) | 3:3; 380 to 480 V | 200 to 500 kW at 400 or 480 V, in 50 kW power-module steps | Current | Schneider Electric Canada, GVL200K500DS; Schneider Electric Canada, Galaxy VL 200 scalable to 500 kW (GVL200K500DS) |
| APC Easy UPS 3M E3MUPS120KHS (120 kVA, 400 V) | 3:3, 380 to 415 V | 60 to 200 kVA at 400 V | Current | Schneider Electric, E3MUPS120KHS; Schneider Electric, Easy UPS 3M 120 kVA (E3MUPS120KHS) |
| Eaton 9395XC 9395XC, 1,125 to 2,250 kW, 480 V 3-wire | 480 V 3-wire in and out | 1,125 to 2,250 kW at 480 V (3-wire) | Current | Eaton, 9395XC UPS page |
Sources, checked October 3, 2026: values as each manufacturer publishes them for the model shown; “Not stated” means the page we read does not give the value.
The smallest three-phase frames
The three-phase models above go down to 5 kVA (Liebert ITA2), 8 kW (Eaton 93PS), 10 kVA (Eaton 9355, Easy UPS 3S) and 10 kW (Eaton 93PM, and about 10 kW for the Galaxy VS) at 208 V. Single-phase units exist at these ratings too, so the choice depends on the supply and the load. If the panel feeding the room is three-phase and the load will grow, a small three-phase frame spreads the load across all three phases of the building supply.
3:1, three-phase in and single-phase out
Eaton sells the 91PS as the 3:1 version of the 93PS: three-phase input, single-phase output. Socomec lists both 1ph + N 230 V and 3ph + N 400 V outputs in the MASTERYS GP4 range. A 3:1 UPS draws a balanced load from the building while feeding single-phase equipment.
Neutral and wiring
Three-phase models differ in how the neutral is handled. Schneider lists the Galaxy VS 208 V model with a 4-wire or 5-wire input and a 5-wire output (3P + N + E), and the 480 V model with a 4-wire input (3P + E). Vertiv's Liebert APM2 208 V output is 3-phase 3-wire plus neutral and PE, and Eaton lists the 9395XC as 480 V 3-wire in and out. At 208Y/120 V the neutral serves 120 V loads directly; behind a 480 V 3-wire UPS, 120 V loads need a transformer downstream.
Both kinds are listed among the single-phase and three-phase UPS systems online, from rack units to three-phase frames, and UPS service for every major brand covers both once installed.
Frequently asked questions
What is the smallest three-phase UPS?
Among the current families we track, the Vertiv Liebert ITA2 starts at 5 kVA (208/220 V, 3:3) and the Eaton 93PS at 8 kW.
What is a 3:1 UPS?
A UPS with three-phase input and single-phase output. Eaton's 91PS is the 3:1 version of the 93PS.
Does a three-phase UPS need a neutral?
It depends on the model and voltage: Schneider lists the Galaxy VS 208 V output as 5-wire (3P + N + E), while Eaton lists the 9395XC as 480 V 3-wire, with no neutral.
Can a three-phase UPS feed single-phase loads?
Yes. A 208Y/120 V three-phase UPS feeds 120 V loads from each phase to neutral, and 3:1 models such as the Eaton 91PS deliver a single-phase output.
Related guides and systems
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