Data Center Transformers
Compare pad-mount, dry-type, cast coil, and unit-substation transformers on rating, voltage, cooling class, K-factor, and lead time. Selection logic and used-market intelligence for data center buyers.
About this Category
Pad-mount, substation, and unit-substation transformers across utility, industrial, and data center applications. Verified kVA, primary/secondary voltage class, BIL, and cooling type across new OEM, refurbished, and used inventory.
Featured Models
The 10 transformers dossiers to read first, ranked on tracked availability, documented specifications, and published pricing rather than alphabetically. All 32 dossiers in the category are listed further down the page.
- Hitachi Energy Ltd (ex-ABB Power Grids) 10-40 MVA power transformer class — $6K–$650K used · lead time 2-12 weeks
- Virginia Transformer Corp (incl. Georgia Transformer) Pad-mounted oil-filled transformers (to 10 MVA) — 67,000 MVA · lead time 1-8 weeks
- Hyosung Heavy Industries / Hyosung HICO, Ltd. (Memphis, TN) EHV/UHV power transformers (69-765 kV, to 2,250 MVA) — 2,250 MVA · lead time 2-12 weeks
- Hitachi Energy Ltd Mobile substations (to 120 MVA / 420 kV) — 120 MVA · lead time 2-12 weeks
- Niagara Power Transformer LLC (Buffalo, NY) Liquid-filled substation transformers (to 50 MVA / 138 kV) — 50 MVA · lead time 2-12 weeks
- WEG S.A. (mobile transformers Brazil; integration by Zest WEG) Mobile substations (50 MVA class observed) — 50 MVA · lead time 2-12 weeks
- Hitachi Energy Ltd (line launched as ABB HiDry72) HiDry dry-type power transformer (above 40.5 kV, to 72.5 kV) — up to 63 MVA · lead time 2-12 weeks
- Hitachi Energy Ltd (ex-ABB Power Grids) HV/EHV power transformer legacy class (69-765 kV) — lead time 2-12 weeks
- Delta Star, Inc. (employee-owned ESOP) Mobile substations (to 133 MVA / 345 kV) — lead time 2-12 weeks
- Eaton Corporation plc DS-3 / DT-3 ventilated dry-type — lead time 1-2 weeks (dealer stock)
Data Center Transformers Models (32)
Every model below has a specification dossier with verified ratings, pricing context, and lead-time intelligence.
Delta Star, Inc. (employee-owned ESOP) Mobile substations (to 133 MVA / 345 kV) — Delta Star, Inc. (employee-owned ESOP)
Eaton Corporation plc DS-3 / DT-3 ventilated dry-type — Eaton Corporation plc · 112.5 kVA – 10,000 kVA
Eaton Corporation plc MD-series motor drive isolation — Eaton Corporation plc · 7.5-1500 kVA
Eaton Corporation plc, Cooper Power series Envirotran FR3 pad-mounted transformers — Eaton Corporation plc, Cooper Power series · 45-10,000 kVA
Eaton Corporation plc, Cooper Power series Envirotran hardened data center pad-mounted transformer — Eaton Corporation plc, Cooper Power series
ERMCO (subsidiary of Arkansas Electric Cooperatives, Inc.) Three-phase pad-mounted transformers (30-3,000 kVA) — ERMCO (subsidiary of Arkansas Electric Cooperatives, Inc.) · 30-3,000 kVA
GE Vernova Inc. (Prolec GE, incl. Prolec-GE Waukesha) Generator step-up transformers (to 1,000 MVA / 765 kV) — GE Vernova Inc. (Prolec GE, incl. Prolec-GE Waukesha) · 600 1-phase / 900 3-phase MVA
HD Hyundai Electric Co., Ltd. (HD Hyundai Power Transformers USA, Montgomery AL) HV/EHV power transformers (Montgomery, AL) — HD Hyundai Electric Co., Ltd. (HD Hyundai Power Transformers USA, Montgomery AL)
Hitachi Energy Ltd EconiQ power transformer portfolio (natural ester) — Hitachi Energy Ltd · 115/21 kV, 40 MVA
Hitachi Energy Ltd Liquid-filled substation transformers (750-20,000 kVA) — Hitachi Energy Ltd · 750-20,000 kVA
Hitachi Energy Ltd Mobile substations (to 120 MVA / 420 kV) — Hitachi Energy Ltd · 120 MVA
Hitachi Energy Ltd RESIBLOC — Hitachi Energy Ltd · up to 63 MVA
Hitachi Energy Ltd TXpand rupture-resistant tank system — Hitachi Energy Ltd
Hitachi Energy Ltd (ex-ABB Power Grids) 10-40 MVA power transformer class — Hitachi Energy Ltd (ex-ABB Power Grids) · 10-40 MVA base
Hitachi Energy Ltd (ex-ABB Power Grids) HV/EHV power transformer legacy class (69-765 kV) — Hitachi Energy Ltd (ex-ABB Power Grids)
Hitachi Energy Ltd (line launched as ABB HiDry72) HiDry dry-type power transformer (above 40.5 kV, to 72.5 kV) — Hitachi Energy Ltd (line launched as ABB HiDry72) · 100 kVA – 40,000 kVA (40 MVA)
Howard Industries, Inc. (Howard Power Solutions) Three-phase pad-mounted transformers (45-10,000 kVA) — Howard Industries, Inc. (Howard Power Solutions)
Howard Industries, Inc. (Howard Power Solutions) Unit substation and medium power transformers (225-10,000 kVA) — Howard Industries, Inc. (Howard Power Solutions)
Hyosung Heavy Industries / Hyosung HICO, Ltd. (Memphis, TN) EHV/UHV power transformers (69-765 kV, to 2,250 MVA) — Hyosung Heavy Industries / Hyosung HICO, Ltd. (Memphis, TN) · 2,250 MVA
MGM Transformer Company (Commerce, CA) K-Factor rated dry-type transformers (K-4 / K-9 / K-13) — MGM Transformer Company (Commerce, CA) · 15-1,000 kVA
Niagara Power Transformer LLC (Buffalo, NY) Liquid-filled substation transformers (to 50 MVA / 138 kV) — Niagara Power Transformer LLC (Buffalo, NY) · 50 MVA
Pennsylvania Transformer Technology, Inc. (a Quanta Services company) Pad-mounted transformers (500-7,500 kVA) — Pennsylvania Transformer Technology, Inc. (a Quanta Services company) · 500-7,500 kVA
Pennsylvania Transformer Technology, Inc. (a Quanta Services company) Power and substation transformers (5-750 MVA, to 765 kV) — Pennsylvania Transformer Technology, Inc. (a Quanta Services company)
Powersmiths International Corp., Socomec Group E-Saver OPAL series LV dry-type — Powersmiths International Corp., Socomec Group · appropriately K-rated
Schneider Electric SE Trihal cast-resin dry-type transformer — Schneider Electric SE · 160 kVA-15 MVA
Siemens Energy AG (Grid Technologies) FITformer fluid-immersed distribution transformers — Siemens Energy AG (Grid Technologies) · 421M USD Charlotte NC
Siemens Energy AG (Grid Technologies) GEAFOL / GEAFOL Neo — Siemens Energy AG (Grid Technologies)
Siemens Energy AG (Grid Technologies) Sensformer connectivity platform (now within the Noedra portfolio) — Siemens Energy AG (Grid Technologies)
TRAFO Power Solutions (Pty) Ltd (TMC Transformers S.p.A. partner) TMC cast-resin dry-type — TRAFO Power Solutions (Pty) Ltd (TMC Transformers S.p.A. partner) · 50 kVA-25 MVA
Virginia Transformer Corp (incl. Georgia Transformer) Pad-mounted oil-filled transformers (to 10 MVA) — Virginia Transformer Corp (incl. Georgia Transformer) · 500 kVA – 100 MVA
WEG S.A. (mobile transformers Brazil; integration by Zest WEG) Mobile substations (50 MVA class observed) — WEG S.A. (mobile transformers Brazil; integration by Zest WEG) · 50 MVA
WEG S.A. (WEG Transformers USA, Washington, MO) Large power transformers (10-350 MVA US; to 500 MVA Brazil) — WEG S.A. (WEG Transformers USA, Washington, MO) · 10-350 MVA
Compare Data Center Transformers (32 models)
Every published model in this category, compared on the specifications a data center buyer filters on first. Values come from each model dossier; an em dash means the specification is not documented, never an estimate.
| Model | OEM | Type | Rating | Primary voltage | Secondary voltage | Cooling class | Impedance | K-factor | Lead time |
|---|---|---|---|---|---|---|---|---|---|
| MD-series motor drive isolation | Eaton Corporation plc | LV Dry-Type | 7.5-1500 kVA | — | — | — | — | K-4 / K-13 / K-20 | New: Distributor quote; class stock ships 3-5 business days (Maddox) · Used: 1-2 weeks (dealer stock) |
| K-Factor rated dry-type transformers (K-4 / K-9 / K-13) | MGM Transformer Company (Commerce, CA) | LV Dry-Type | 15-1,000 kVA | 480 / 600 V delta | 208Y/120, 480Y/277 | 150 C | — | K-4 / K-9 / K-13 | New: Stocked sizes fast-ship; 20-32 weeks class otherwise · Used: 1-4 weeks (dealer stock) |
| Three-phase pad-mounted transformers (30-3,000 kVA) | ERMCO (subsidiary of Arkansas Electric Cooperatives, Inc.) | Pad-Mount Distribution | 30-3,000 kVA | 2.4-35 kV | — | 65 C | — | — | New: 40-65 weeks (pad-mount class) · Used: 1-8 weeks |
| Envirotran FR3 pad-mounted transformers | Eaton Corporation plc, Cooper Power series | Pad-Mount Distribution | 45-10,000 kVA | 2,400-34,500 V | 120-15,000 V | — | — | — | New: 80-120 weeks OEM; stock units 1-2 business days · Used: 1-8 weeks |
| DS-3 / DT-3 ventilated dry-type | Eaton Corporation plc | LV Dry-Type | 112.5 kVA – 10,000 kVA | 2.4 kV – 34.5 kV | 208V – 4,160V | 150 std; 115 / 80 optional C | — | — | New: Distributor stock to 20-32 weeks by size · Used: 1-2 weeks (dealer stock) |
| FITformer fluid-immersed distribution transformers | Siemens Energy AG (Grid Technologies) | Substation (Liquid-Filled) | 421M USD Charlotte NC | — | 250-800 V | — | — | — | New: 40-65 weeks pad-mount class; 65-95 weeks substation class · Used: 2-12 weeks |
| Pad-mounted transformers (500-7,500 kVA) | Pennsylvania Transformer Technology, Inc. (a Quanta Services company) | Pad-Mount Distribution | 500-7,500 kVA | — | — | — | — | — | New: 40-65 weeks (pad-mount class); PTT-specific figures unpublished · Used: 1-8 weeks (class channel) |
| Liquid-filled substation transformers (750-20,000 kVA) | Hitachi Energy Ltd | Substation (Liquid-Filled) | 750-20,000 kVA | 69 kV | — | — | — | — | New: 65-95 weeks (5-25 MVA class) · Used: 2-12 weeks |
| 10-40 MVA power transformer class | Hitachi Energy Ltd (ex-ABB Power Grids) | Power & Substation (Oil-Filled) | 10-40 MVA base | 69-138 kV | — | — | — | — | New: 128-144 weeks (class average) · Used: 2-12 weeks |
| Large power transformers (10-350 MVA US; to 500 MVA Brazil) | WEG S.A. (WEG Transformers USA, Washington, MO) | Power & GSU (Oil-Filled) | 10-350 MVA | 24.94-400 kV | — | ONAN / ONAF / ODAF / KNAN / KNAF | — | — | New: Quoted; class 120 weeks average, 80-210 weeks large · Used: 2-12 weeks |
| Liquid-filled substation transformers (to 50 MVA / 138 kV) | Niagara Power Transformer LLC (Buffalo, NY) | Substation (Liquid-Filled) | 50 MVA | — | — | — | — | — | New: 65-110 weeks (class, by MVA band); Niagara-specific figures unpublished · Used: 2-12 weeks |
| TMC cast-resin dry-type | TRAFO Power Solutions (Pty) Ltd (TMC Transformers S.p.A. partner) | Cast-Resin Dry-Type | 50 kVA-25 MVA | — | — | AN / AF / AFAF / AFAW/WF | — | — | New: Engineered to order via TMC Italy; no published lead times · Used: No used channel observed |
| Mobile substations (50 MVA class observed) | WEG S.A. (mobile transformers Brazil; integration by Zest WEG) | Mobile Substation | 50 MVA | 110 / 60 (dual-rated) kV | 20 / 30 kV | — | — | — | New: Engineered to order; quoted per project · Used: 2-12 weeks |
| RESIBLOC | Hitachi Energy Ltd | Cast-Resin Dry-Type | up to 63 MVA | 36 kV | 24 kV | — | — | — | New: 20-32 weeks (dry-type class) · Used: 2-12 weeks |
| HiDry dry-type power transformer (above 40.5 kV, to 72.5 kV) | Hitachi Energy Ltd (line launched as ABB HiDry72) | Cast-Resin Dry-Type | 100 kVA – 40,000 kVA (40 MVA) | Up to 36 kV | Up to 3.3 kV | AN/AF | — | — | New: Engineered to order; dry-type class 20-32 weeks at small MVA, longer at power class · Used: 2-12 weeks |
| EconiQ power transformer portfolio (natural ester) | Hitachi Energy Ltd | Power & Substation (Oil-Filled) | 115/21 kV, 40 MVA | — | — | — | — | — | New: 128 weeks class average; project-quoted · Used: 2-12 weeks |
| Mobile substations (to 120 MVA / 420 kV) | Hitachi Energy Ltd | Mobile Substation | 120 MVA | — | — | — | — | — | New: Engineered to order; quoted per project · Used: 2-12 weeks |
| Trihal cast-resin dry-type transformer | Schneider Electric SE | Cast-Resin Dry-Type | 160 kVA-15 MVA | 36 kV | — | — | — | — | New: 20-32 weeks (dry-type class) · Used: 1-8 weeks (European dealers) |
| Pad-mounted oil-filled transformers (to 10 MVA) | Virginia Transformer Corp (incl. Georgia Transformer) | Pad-Mount Distribution | 500 kVA – 100 MVA | 4.16 kV – 230 kV | 480V – 34.5 kV | ONAN/ONAF/OFAF | — | — | New: 40-65 weeks (pad-mount class); company markets shortest-lead-time positioning · Used: 1-8 weeks |
| Generator step-up transformers (to 1,000 MVA / 765 kV) | GE Vernova Inc. (Prolec GE, incl. Prolec-GE Waukesha) | Power & GSU (Oil-Filled) | 600 1-phase / 900 3-phase MVA | 69-765 kV wye | 13.2-25 kV delta | ONAN / ONAF / ODAF | — | — | New: 100-150+ weeks (GSU class); 144 weeks Q2 2025 average · Used: 2-12 weeks |
| EHV/UHV power transformers (69-765 kV, to 2,250 MVA) | Hyosung Heavy Industries / Hyosung HICO, Ltd. (Memphis, TN) | Power & GSU (Oil-Filled) | 2,250 MVA | — | — | — | — | — | New: Contract-scheduled; class high-capacity leads to 4 years · Used: 2-12 weeks |
| Mobile substations (to 133 MVA / 345 kV) | Delta Star, Inc. (employee-owned ESOP) | Mobile Substation | — | — | — | — | — | — | New: Engineered to order; quoted per project · Used: 2-12 weeks |
| Envirotran hardened data center pad-mounted transformer | Eaton Corporation plc, Cooper Power series | Pad-Mount Distribution | — | — | — | — | — | — | New: 80-120 weeks OEM pad-mount class; dedicated data center programs faster · Used: No used channel yet |
| HV/EHV power transformers (Montgomery, AL) | HD Hyundai Electric Co., Ltd. (HD Hyundai Power Transformers USA, Montgomery AL) | Power & GSU (Oil-Filled) | — | — | — | — | — | — | New: Contract-scheduled; class 120 weeks average, 80-210 weeks large · Used: 2-12 weeks |
| TXpand rupture-resistant tank system | Hitachi Energy Ltd | Power & Substation (Oil-Filled) | — | — | — | — | — | — | New: Follows host power transformer (128 weeks class average) · Used: 2-12 weeks |
| HV/EHV power transformer legacy class (69-765 kV) | Hitachi Energy Ltd (ex-ABB Power Grids) | Power & Substation (Oil-Filled) | — | 69-765 kV | — | — | — | — | New: 144 weeks average (GSU); up to 4 years high-capacity · Used: 2-12 weeks |
| Three-phase pad-mounted transformers (45-10,000 kVA) | Howard Industries, Inc. (Howard Power Solutions) | Pad-Mount Distribution | — | — | — | — | — | — | New: 40-65 weeks (pad-mount class) · Used: 1-8 weeks |
| Unit substation and medium power transformers (225-10,000 kVA) | Howard Industries, Inc. (Howard Power Solutions) | Substation (Liquid-Filled) | — | 2,400-69,000 V | 120-8,400 V or 14,400Y | OA (+FA option) / 65 C | — | — | New: 65-95 weeks (substation class) · Used: 2-12 weeks |
| Power and substation transformers (5-750 MVA, to 765 kV) | Pennsylvania Transformer Technology, Inc. (a Quanta Services company) | Power & Substation (Oil-Filled) | — | 69 / 138 / 345 / to 765 kV | — | — | — | — | New: 65-110 weeks (5-50 MVA class); up to 4 years high-capacity · Used: 2-12 weeks |
| E-Saver OPAL series LV dry-type | Powersmiths International Corp., Socomec Group | LV Dry-Type | appropriately K-rated | — | — | — | — | appropriately K-rated | New: Quoted; 2024 factory expansion added capacity · Used: No used channel observed |
| GEAFOL / GEAFOL Neo | Siemens Energy AG (Grid Technologies) | Cast-Resin Dry-Type | — | — | — | — | — | — | New: 20-32 weeks (dry-type class); large units longer · Used: Auction-cycle dependent |
| Sensformer connectivity platform (now within the Noedra portfolio) | Siemens Energy AG (Grid Technologies) | Digital & Monitoring | — | — | — | — | — | — | New: Ships embedded with host transformer · Used: Not traded separately |
Which Transformer Do You Need
Indoor installation in a fire-rated space
Dry-type and cast coil units carry no liquid, so they avoid the containment, spill response, and fire-separation obligations that follow an oil-filled unit indoors. Cast coil buys sealed windings and better humidity tolerance at a higher price than ventilated dry-type. Dry-Type and Cast Coil Transformers: Selection, Sizing, and Where Each Belongs covers the detail.
Outdoor pad at the utility interface
Pad-mount units are the default at the service entrance: tamper-resistant enclosure, dead-front terminations, and no separate vault. Confirm DOE 2016 efficiency compliance and whether the fluid is mineral oil or a natural ester such as FR3. Pad Mount Transformers: Sizing, Configurations, and Current Lead Times covers the detail.
Space-constrained rooms with integrated switchgear
A unit substation ties primary switch, transformer, and secondary switchgear into one close-coupled lineup, removing cable runs and shortening the footprint. The cost is flexibility, and lead time is set by the slowest component in the lineup. Data Center Transformers: The Complete Selection and Procurement Guide covers the detail.
Nonlinear data center load
IT loads draw harmonic current, which heats a transformer beyond what its nameplate kVA implies. A K-rated or harmonic-mitigating unit is sized for that heating; a standard-rated unit has to be derated instead. Data Center Transformer Sizing Guide: Load Math, K-Factor, and Lead-Time Reality covers the detail.
Used and Surplus Transformers
New pad-mount and power transformer lead times run in years at the OEM, which is why schedule-driven projects look at surplus and used units. The lead-time column states what each dossier documents for new and used channels. SecondWatt holds no stock and sets no price: send the rating, voltage, and type and the request is routed to sellers holding matching equipment. List equipment you hold.
Pricing Tiers
- New OEM — direct manufacturer with full warranty and lead times of 12–36 months.
- Gray Market — surplus new inventory at discounted pricing, available immediately.
- Refurbished — overhauled units with restored specs and limited warranty.
- Used — operational units with documented run-time and condition reports.
Related Intelligence
- Pad Mount Transformers: Sizing, Configurations, and Current Lead Times
- Dry-Type and Cast Coil Transformers: Selection, Sizing, and Where Each Belongs
- Data Center Transformers: The Complete Selection and Procurement Guide
- Data Center Transformer Sizing Guide: Load Math, K-Factor, and Lead-Time Reality