Single Phase Pad Mount Transformer for Underground Electrical
Distribution Networks
Product Overview
The single-phase pad-mounted oil-immersed transformer is a
US-standard fully sealed distribution equipment specifically
designed for overseas power distribution systems in North America,
Latin America, and other regions. It fully complies with and
exceeds international standards including ANSI, DOE, IEEE, and CSA,
serving as core equipment for low-voltage power distribution in
residential, commercial, public facilities, and various other
applications.
This product series features an independent compartment structure
with core advantages including compact design, small footprint,
light weight, low noise, minimal loss, safety reliability,
anti-theft protection, and maintenance-free operation. It can be
directly installed on outdoor ground foundations without additional
power distribution rooms, significantly reducing infrastructure
costs.
With rated capacity covering 10kVA-250kVA and maximum input voltage
up to 34.5kV, it perfectly adapts to mainstream North American
power distribution systems. Applications include residential areas,
commercial centers, hospitals, parks, schools, rural power grids,
and small industrial/commercial enterprises.
We independently develop and produce key components including oil
tanks and iron cores, with monthly delivery capacity exceeding 600
units and fast delivery within 35 days. We support fully customized
production to meet personalized project requirements.
Core Structure and Process Advantages
High-Efficiency Energy-Saving Iron Core System
Constructed from high-quality cold-rolled grain-oriented silicon
steel sheets using multi-stage step-lapped full-oblique joint
lamination process. This design significantly reduces magnetic
resistance, effectively lowering no-load loss and no-load current
while complying with DOE energy efficiency standards. The iron core
undergoes vacuum impregnation and overall sealing treatment,
providing high mechanical strength, low operating noise, and
long-term operational stability suitable for all-weather outdoor
conditions.
High-Reliability Winding Design
- High-voltage winding adopts multi-layer cylindrical structure wound
with high-purity oxygen-free copper wire. Interlayer insulation
uses high-strength insulating paper treated with vacuum
impregnation process, ensuring excellent insulation performance and
strong resistance to short circuit and lightning impulse.
- Low-voltage winding features foil-wound structure with tight
winding and high concentricity, providing excellent heat
dissipation performance that effectively reduces load loss and
improves transformer operating efficiency, eliminating overheating
risk during long-term full-load operation.
Fully Sealed Oil-Immersed Structure and Protection Design
- Adopts fully sealed corrugated tank structure with environmentally
friendly mineral oil (vegetable insulating oil optional) as
insulating cooling medium, completely isolating air and moisture to
prevent oil deterioration and insulation aging.
- Enclosure constructed from NEMA 3R weatherproof and
corrosion-resistant steel plate with high-temperature electrostatic
spraying surface treatment, featuring strong weather resistance
adaptable to extreme environments from -40℃ to +50℃.
- Incorporates Dead Front design with all live parts completely
enclosed, no exposed live parts on operation surface, equipped with
anti-theft locks to prevent misoperation and electricity theft.
Complete Protection and Operation System
- Equipped with standard accessories including pressure relief
valves, oil level gauges, thermometers, and tap changers to
comprehensively ensure safe transformer operation.
- Double-compartment structure provides complete isolation between
high-voltage and low-voltage sides, supporting ring network/radial
wiring to meet different power distribution system requirements.
- Supports off-circuit voltage regulation for flexible adjustment
according to on-site voltage requirements to ensure stable output
voltage.
Core Technical Specifications
| Rating (kVA) | High Voltage (kV) | No Load Loss | On Load Loss | Height (mm) | Depth (mm) | Width (mm) | Oil Weight (kg) | Total Weight (kg) |
|---|
| 15 kVA | 34.5/19.92 13.8/8 13.2/7.6 12.47/7.2 or others | 50 | 195 | 840 | 740 | 610 | 45 | 294 |
| 25 kVA | | 80 | 290 | 840 | 740 | 610 | 68 | 362 |
| 37.5 kVA | | 106 | 360 | 840 | 760 | 610 | 75 | 476 |
| 50 kVA | | 135 | 500 | 840 | 810 | 610 | 93 | 553 |
| 75 kVA | | 190 | 650 | 840 | 860 | 610 | 132 | 672 |
| 100 kVA | | 280 | 1010 | 910 | 1200 | 965 | 230 | 714 |
| 167 kVA | | 435 | 1530 | 1000 | 1200 | 965 | 265 | 913 |
| 250 kVA | | 550 | 2230 | 1250 | 1300 | 1430 | 325 | 1106 |
Default low-voltage output is North American standard voltages such
as 120/240V, 240/480V, which can be customized according to user
requirements. Parameters including capacity, voltage, and loss
support personalized customization.
Core Performance Highlights
- US-Standard Compliance, Global Adaptability: Fully complies with North American standards including ANSI, DOE,
IEEE, and CSA, with UL certification. Directly adaptable to
overseas power distribution systems without additional
modification.
- Ultimate Energy Saving, Cost Reduction & Efficiency Improvement: Low-loss iron core and winding design with no-load and load losses
far below industry standards, complying with DOE energy efficiency
requirements.
- Safe, Reliable and Maintenance-Free: Fully sealed structure with Dead Front design, no exposed live
parts, anti-theft and anti-misoperation features, maintenance-free
operation with strong resistance to short circuit and impact.
- Compact and Aesthetic, Easy Installation: Low-profile, compact design with attractive appearance, direct
installation on outdoor ground foundations without power
distribution rooms, suitable for scenarios with high landscape
requirements.
- Customized Service, Fast Delivery: Supports full-dimensional customization of capacity, voltage,
accessory configuration, and insulating medium. Independent
production of core components with monthly capacity over 600 units
and fast delivery within 35 days.
- Environmentally Friendly and Durable, Ultra-Long Service Life: Utilizes environmentally friendly insulating oil, no harmful
emissions, fully sealed structure to eliminate pollution, with
service life exceeding 30 years.
Application Scenarios
- Residential Power Distribution: Residential areas, villas, apartments - providing safe and stable
single-phase power supply
- Commercial Facilities: Commercial centers, convenience stores, small shops - meeting
commercial power demand
- Public Facilities: Hospitals, schools, parks, municipal projects - ensuring reliable
power supply for public facilities
- Rural Power Grid: Rural power distribution, agricultural irrigation, power supply in
remote areas - solving long-distance power distribution problems
- Industrial and Commercial Scenarios: Small factories, gas stations, communication base stations -
meeting industrial and commercial single-phase power demand
Quality Assurance and Service
This single-phase pad-mounted transformer series is produced in
strict accordance with ISO9001 quality management system. All
products pass full type testing per ANSI/IEEE standards, with 100%
independent production of core components and comprehensive
performance testing before delivery.
We provide one-stop foreign trade services from selection design,
manufacturing, export customs declaration, installation guidance to
after-sales operation and maintenance. We support customized
specifications and provide Chinese/English technical documents and
certification documents to meet overseas project compliance
requirements.
After-sales service includes lifelong technical support, spare
parts supply, and quick-response maintenance services, ensuring
stable equipment operation throughout the entire lifecycle.

Frequently Asked Questions
Can I have a sample order?
Yes, we welcome sample orders to test and check quality.
What is the lead time?
Mass production time 15-25 days.
How long is the warranty?
24 months from B/L. If there are any accessory problems, just
provide photos of damaged accessory for free service. We provide
easily damaged accessories according to product quantity and
technical support as needed.
Is OEM/ODM available?
Yes! We are a manufacturer with our own R&D team and can
customize products according to customer drawings or requirements.
Customized services include: custom colors and special functions,
custom boxes, customer logo printing, and other product ideas. All
customized services must be confirmed before production.
How to control the products quality?
Our company owns core technology with CE certification for all
products. We have professional engineers and strict production
processes according to drawings. Each process has technical
instructors with regular QC supervision. We conduct performance
tests during production and comprehensive quality tests upon
completion.