Product Overview
What Is a Pad Mounted Transformer?
A pad-mounted transformer uses an oil-immersed design to support reliable underground power distribution. It sits on a concrete pad inside a protective metal enclosure and integrates the transformer unit, high-voltage protection devices, and low-voltage distribution components into one compact system.
Single-Phase vs Three-Phase Solutions
Single-Phase Pad Mounted Transformer (10 kVA – 333 kVA)
Primary Applications: Underground Residential Distribution (URD), street lighting, housing developments, and light commercial single-phase loads.
Key Features: Ultra-compact footprint, dead-front elbow connections, and loop or radial feed designs tailored to regional utility specifications.
Three-Phase Pad Mounted Transformer (45 kVA – 5000 kVA)
Primary Applications: Commercial plazas, industrial facilities, healthcare centers, and renewable energy (solar/wind) step-up systems.
Key Features: Heavy-duty enclosure, multi-position load break switches, Bay-O-Net and current-limiting fuse protection, compliant with ANSI/IEEE and DOE energy efficiency standards.
Available Configurations & Custom Options
Key Features
Pad mounted transformers combine a compact enclosed structure, oil-immersed insulation, and flexible electrical configurations to meet the needs of different outdoor power distribution projects.
Technical Specifications
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Our pad-mounted transformers are available in single-phase and three-phase configurations, with flexible capacity, voltage, connection, and enclosure options. The following tables summarize typical specifications for each series. Final ratings, configurations, and applicable standards depend on the selected model and project requirements.
Single Phase Pad Mounted Transformer
| Parameter | Specifications |
| Rated Capacity | 10, 15, 25, 50, 75, 100, 167, 250, 333 kVA |
| Primary Voltage | 7.2–34.5 kV, depending on design |
| Secondary Voltage | 120/240 V, 240/480 V; other options available upon request |
| Frequency | 60 Hz standard; 50 Hz available upon request |
| Basic Impulse Level (BIL) | 60–200 kV, depending on voltage class |
| Secondary Connection | 2-wire or 3-wire split-phase |
| Cooling Type | ONAN (Oil Natural, Air Natural), with integrated corrugated radiator |
| Insulating Fluid | Mineral oil standard; FR3 natural ester fluid optional |
| Enclosure Material | Galvanized steel |
| Enclosure Finish | RAL 6005 dark green, weather-resistant coating |
| Enclosure Protection Rating | IP33D, subject to confirmation for the selected model |
| Ambient Temperature | −30°C to +45°C anti-salt-fog treatment available upon request |
| Applicable Standards | IEEE C57.12.00 other applicable standards depend on the design and verified requirements |
Three Phase Pad Mounted Transformer
| Parameter | Specifications |
| Rated Capacity | 50, 100, 250, 500, 750, 1,000, 1,500, 2,000, 2,500 kVA |
| Primary Voltage | 10–35 kV, depending on design |
| Secondary Voltage | 208 V, 240 V, 400 V, 480 V, 690 V; other options available upon request |
| Frequency | 60 Hz standard; 50 Hz available upon request |
| Basic Impulse Level (BIL) | 95–200 kV, depending on voltage class |
| Vector Group | Dyn11, Yyn0, or other configurations subject to design |
| Cooling Type | ONAN (Oil Natural, Air Natural), with integrated corrugated radiator |
| Insulating Fluid | Mineral oil standard; FR3 natural ester fluid optional |
| Enclosure Material | Galvanized steel |
| Enclosure Finish | RAL 6005 dark green, weather-resistant coating |
| Enclosure Protection Rating | IP33D, subject to confirmation for the selected model |
| Ambient Temperature | −30°C to +45°C; anti-salt-fog treatment available upon request |
| Applicable Standards | IEEE C57.12.00; IEEE C57.12.34 and IEEE C57.12.28 where applicable to the verified design |
Applications
Residential and Commercial Buildings
Pad mounted transformers supply power to residential communities, apartment complexes, shopping centers, office buildings, and other commercial developments.
Industrial Facilities
Industrial facilities use pad mounted transformers to supply electrical power to manufacturing plants, warehouses, processing facilities, and other industrial sites.
Utility Distribution Networks
Utility providers use pad mounted transformers in underground power distribution networks to serve residential, commercial, and mixed-use areas.
Manufacturing & Quality Assurance
Quality Control Throughout Production
We focus on manufacturing quality and inspection throughout the production of our pad-mounted transformers. From incoming material checks and component assembly to final testing, each applicable stage follows established quality control procedures to help ensure that the finished product meets the agreed technical specifications.
Incoming inspection helps verify the quality and suitability of key materials and components before they enter the production process.
Production checks cover applicable manufacturing and assembly stages, including core and winding assembly, tank fabrication, enclosure assembly, and component installation.
Before shipment, each transformer undergoes the applicable inspections and electrical tests specified for its design and order requirements. Test reports and related technical documents can be provided when available for the selected model.
Why Choose Henan Automation?
Combining 20+ years of power transformer engineering expertise with international compliance to power your projects globally.
Manufacturing Capability
Customized Solutions
FAQ
Pad-mounted transformers distribute electricity through underground power networks to residential communities, commercial buildings, industrial facilities, and suitable renewable energy projects.
Yes. Both single-phase and three-phase configurations are available within the applicable product ranges. Capacity, voltage ratings, and other specifications depend on the selected model.
Yes. All our pad mounted transformers are designed and manufactured in strict accordance with ANSI/IEEE C57.12.00, C57.12.34 and C57.12.28 standards, with corresponding factory test reports available upon request.
Available configurations can be reviewed according to project requirements, including rated capacity, voltage ratings, frequency, insulating liquid, enclosure requirements, and applicable accessories. Final options are subject to technical confirmation.
Yes, absolutely. Over 80% of our orders are customized. You can send us your SLD, primary/secondary voltage requirements, and special utility grid specifications, and our engineering team will provide detailed approval drawings within 24–48 hours.
Standard single-phase models: 10–15 working days. Standard three-phase models: 15–20 working days. Fully customized configurations: 25–30 working days.
