Distribution Transformer
Sinotech Electric supplies distribution transformers designed for utility companies, EPC contractors, and electrical distributors who need reliable, cost-effective power distribution solutions. Covering voltage classes from 10kV to 35kV with capacities ranging from 50kVA to 2,500kVA, our distribution transformers serve residential neighborhoods, commercial districts, industrial zones, and rural electrification projects across 80+ countries worldwide.
Sinotech distribution transformers are available in multiple mounting configurations:
Pole-mounted (50kVA–500kVA) — overhead installation for rural and semi-urban networks
Pad-mounted (100kVA–2,500kVA) — ground-level installation with tamper-resistant enclosures
Ground-mounted / Substation type (315kVA–2,500kVA) — for dedicated substation rooms
Custom Distribution Transformer Manufacturer in China
Sinotech offers distribution transformers in both oil-immersed and dry type configurations to match different installation requirements. Oil-immersed models are available in S11, S13, and S20 energy-efficient series, ideal for outdoor pole-mounted, pad-mounted, and ground-mounted installations. Dry type models feature epoxy resin cast coils with Class F or Class H insulation, suited for indoor substations, commercial buildings, and fire-sensitive environments.
Max. Voltage
35kV
Capacity
50kVA to 2,500kVA
Standards
ANSI/IEEE/DOE/CSA/AS
What Are the Standard Size of Sinotech Distribution Transformer?
| Transformer Capacity (kVA) | High Voltage (kV) | High Voltage Tap Range (%) | Low Voltage (kV) | Rated Frequency (Hz) | Connection Group Model Number | No-load Loss (W) | Load Loss (W) | No-load Current (%) | Noise Level (dB) | Short Circuit Impedance (%) | Gauge A×B (mm×mm) | Dimensions Length×Width×Height (m) | Weight (kg) |
| 30 | 6 6.3 6.6 10 10.5 11 | 52× 2.5 | 0.4 | 50 | D,yn11 Y,yn0 | 80 | 630/600 | 0.5 | 43 | 4.0 | 400×400 | 830x650x950 | 380 |
| 50 | 100 | 910/870 | 0.5 | 43 | 400×400 | 850×680×960 | 420 | ||||||
| 80 | 130 | 1310/1250 | 0.45 | 44 | 400×400 | 870×700×1010 | 520 | ||||||
| 100 | 150 | 1580/1500 | 0.45 | 44 | 400×400 | 900×720×1020 | 580 | ||||||
| 160 | 200 | 2310/2200 | 0.4 | 46 | 550×550 | 1190×770×1090 | 790 | ||||||
| 200 | 240 | 2730/2600 | 0.4 | 47 | 550×550 | 1260×850×1120 | 880 | ||||||
| 250 | 290 | 3200/3050 | 0.35 | 48 | 550×550 | 1300×860×1140 | 1020 | ||||||
| 315 | 340 | 3830/3650 | 0.35 | 48 | 660×660 | 1370×910×1160 | 1220 | ||||||
| 400 | 410 | 4520/4300 | 0.35 | 48 | 660×660 | 1400×920×1220 | 1430 | ||||||
| 500 | 480 | 5410/5150 | 0.3 | 49 | 660×660 | 1530×1000×1280 | 1730 | ||||||
| 630 | 570 | 6200 | 0.25 | 49 | 4.5 | 660×660 | 1610x1060x1320 | 2100 | |||||
| 800 | 700 | 7500 | 0.18 | 50 | 660×820 | 1670x1120x1380 | 2480 | ||||||
| 1000 | 830 | 10300 | 0.17 | 50 | 660×820 | 1720×1160×1400 | 2880 | ||||||
| 1250 | 970 | 12000 | 0.17 | 52 | 660×820 | 1770×1180×1500 | 3500 | ||||||
| 1600 | 1170 | 14500 | 0.16 | 52 | 820×1070 | 1860x1240x1600 | 4130 | ||||||
| 2000 | 1360 | 18300 | 0.16 | 54 | 5.0 | 820×1070 | 1950x1320x1720 | 5420 | |||||
| 2500 | 1600 | 21200 | 0.15 | 54 | 820×1070 | 2070x1400x1800 | 6500 |
Note: Above Is Technical Parameters of 10kV Class S13 Series Energy-saving Distribution Transformer
Custom Distribution Transformer Solutions
Every Sinotech distribution transformer is built with premium components: grain-oriented silicon steel cores for reduced no-load losses, oxygen-free copper or aluminum windings for superior conductivity, and high-grade mineral oil or FR3 natural ester for oil-immersed units. Standard secondary output is 0.4kV, with custom voltage ratios and tap configurations available for specific grid requirements. Impedance values follow IEC 60076 standards with custom options from 4% to 6%.
Sinotech custom distribution transformers have been deployed in rural electrification networks in West Africa with unstable grid voltage and extreme humidity, mining substations in the Andes at 3,800 meters altitude with daily temperature swings of 40°C, residential estates in Southeast Asia where noise complaints shut down lesser transformers, and coastal industrial zones in the Middle East where salt corrosion destroys standard tank coatings within two years.
Urban Power Distribution
Rural Electrification
Renewable Energy
Advantages of Sinotech Distribution Transformer
Distribution transformers play an indispensable role in modern power distribution networks, efficiently stepping down medium grid voltage to safe low-voltage levels for end-users while maximizing reliability and cost-effectiveness.
High Energy Efficiency
Engineered for superior voltage step-down performance, our transformers minimize core losses during your daily load cycles. This energy conservation complies fully with DOE efficiency standards, delivering consistent, stable power to keep your business running smoothly.
High Power Reliability
By regulating localized grid voltage and managing load fluctuations, our equipment strengthens your regional power stability. Our heavy-duty construction and reliable insulation prevent unexpected outages, guaranteeing uninterrupted electricity for your project facilities.
Optimized Cost Savings
Compared to large high-voltage units, our distribution transformers lower your initial capital expenditure. Specially optimized for your capacity needs, we help you reduce purchasing, installation, and ongoing maintenance costs across the equipment’s total lifetime.
Lower Line Loss Levels
By stepping down voltage directly at your load center, our distribution transformers minimize energy loss during local power delivery. Placing the transformer close to your facility reduces long-distance transmission waste, boosting overall system energy efficiency.
Custom Flexible Design
We engineer each distribution transformer to match your unique site constraints, voltage levels, and terminal layouts. From custom cabinet dimensions to specialized protection switches, we deliver tailored solutions that fit your exact regional project requirements.
Eco Friendly Footprint
Built with compact footprints, our transformers reduce carbon emissions and land usage footprints. Whether you choose eco-friendly dry-type resin insulation or biodegradable FR3 vegetable fluid, we help you achieve a cleaner, greener, and more sustainable energy grid.
Main Types of Distribution Transformer
Depending on your installation environment, safety codes, and load requirements, distribution transformers are divided into four primary structural and insulation types. Whether you need overhead rural power lines, ground-level urban distribution, or indoor fire-safe installations, our factory provides fully customized solutions engineered for maximum long-term reliability and low total cost of ownership.
Pole Mount Transformer
Designed for overhead rural and suburban distribution grids, our pole-mounted transformers offer you a compact, highly budget solution. We engineer these lightweight units for easy installation on utility poles, delivering dependable power for your remote sites.
Pad Mount Transformer
Perfect for your urban centers and commercial complex projects, our pad-mounted transformers deliver tamper-resistant safety at ground level. We enclose these units in tamper-proof steel cabinets, ensuring reliable power supply while preserving site aesthetics.
Dry Type Transformer
When fire safety is your top priority, our dry-type distribution transformers provide an ideal resin-insulated solution. Using air cooling instead of oil, we engineer these units for indoor installations in high-rise buildings, hospitals, and city metro systems.
Oil Immersed Transformer
Built for heavy-duty industrial and outdoor application, our oil-immersed transformers provide superior cooling and thermal efficiency. We utilize high-grade dielectric fluids to maximize load capability and extend your equipment service life in tough sites.
Key Specifications Comparison Matrix
To help you compare technical trade-offs across these four main transformer types, review our parameter matrix below:
| Feature / Type | Pole Mount | Pad Mount | Dry Type | Oil Immersed |
| Mounting / Site | Utility Poles (Overhead) | Concrete Pad (Ground) | Indoor / Enclosure | Outdoor / Indoor Substation |
| Cooling Medium | Mineral Oil | Mineral Oil / FR3 Fluid | Air / Cast Resin | Mineral Oil / Bio-fluid |
| Typical Capacity | 10 kVA – 500 kVA | 75 kVA – 5,000 kVA | 50 kVA – 3,150 kVA | 50 kVA – 10,000+ kVA |
| Fire Safety Level | Standard Outdoor | High (Sealed Enclosure) | Highest (Self-Extinguishing) | Standard to High (with FR3) |
| Initial CAPEX | Lowest | Moderate | Higher | Cost-Effective |
| Best Application | Rural & Suburban Grids | Urban Residential & Solar | High-Rises, Metros, Hospitals | Heavy Industry & Utilities |
How to Select the Right Transformer Type for Your Project
For Overhead Rural Grid Lines:
You are deploying overhead distribution lines in rural, agricultural, or suburban areas with limited ground space and budget constraints. Our lightweight pole mount units offer you a quick, cost-effective setup without requiring expensive concrete foundations.
For Underground Urban Systems:
You need ground-level, underground-fed power for residential subdivisions, commercial plazas, or solar farms requiring tamper-proof public safety. Our pad mount transformers provide sealed, aesthetically pleasing cabinets that integrate into public spaces.
For High Fire Safety Indoors:
Your installation is inside high-rise buildings, hospitals, tunnels, or data centers where strict fire safety codes prohibit oil-filled equipment. Our resin-cast dry type transformers deliver self-extinguishing safety and zero risk of toxic chemical leaks.
For Heavy Industrial Plants:
You require maximum thermal efficiency, high overload capacity, and long service life for heavy industrial plants or outdoor utility networks. Our oil immersed transformers provide rugged cooling performance to ensure continuous power under tough conditions.
Note: If you remain uncertain which of these four transformer types best matches your specific installation site, environmental conditions, or budget, Sinotech’s technical team is ready to evaluate your site requirements and recommend the most cost-effective solution for your grid.
FAQ:
A distribution transformer serves as the final step-down power link in an electrical grid. It converts high-voltage electricity received from transmission lines (such as 10kV–35kV) into safe, usable low-voltage power (such as 400V, 240V, or 120V) for residential homes, commercial complexes, and industrial facilities.
Depending on site space, voltage level, and regional utility codes, distribution transformers can be mounted overhead on utility poles (rural/suburban lines), placed at ground level on concrete pads (urban residential and commercial areas), or installed indoors and inside substations (high-rise buildings, factories, and metros).
Transformer efficiency is enhanced by selecting low-loss magnetic steel cores, maintaining balanced operating loads, ensuring optimal cooling, and performing routine oil or thermal checks. Choosing energy-efficient units compliant with US DOE 2016/2026 or IEC standards also significantly reduces ongoing power losses.
Recommended maintenance includes periodic visual tank inspections, monitoring operating oil and winding temperatures, conducting oil sampling tests for liquid-filled units, cleaning external bushings, checking grounding connections, and preventing prolonged overload conditions.
The most common issues include overheating from severe overload, insulation breakdown caused by voltage surges, liquid leaks from aged gaskets, and excessive operational noise. To prevent these failures, we incorporate hermetically sealed oil tanks, internal pressure relief valves, and robust surge protection into our designs.
Yes, modern distribution transformers are designed for high energy efficiency to minimize carbon emissions. Furthermore, many units use biodegradable natural ester fluids (such as Cargill FR3 vegetable oil) or cast-resin dry-type insulation to eliminate soil pollution risks and enhance environmental safety.
High Quality, Reliable, and Long lasting Distribution Transformer
Sinotech builds each distribution transformers with reinforced insulation for voltage fluctuation tolerance, robust tank construction for extended maintenance intervals. Windings are oxygen-free copper with purity above 99.9%. Insulation is premium-grade Nomex and epoxy resin with verified thermal class. We customize distribution transformers for most conditions — not with generic recommendations, but with engineering analysis and proven solutions.
30+ Years of Industry Expertise
With over 30 years of combined experience in power electrical engineering, Sinotech brings unmatched technical depth to every project. Our team understands the complexities of different voltage levels, load profiles, and environmental conditions.
Large Manufacturing Capability
Sinotech operates a world-class manufacturing base capable of handling both small custom orders and large-volume utility projects. Our scale ensures consistent quality, competitive pricing, and reliable delivery for clients worldwide.
Comprehensive Product Portfolio
Sinotech offers a complete range of power transformation products, eliminating the need for multiple suppliers. From distribution transformers to prefabricated substations, we cover your entire power infrastructure requirements.
Full Customization Capability
Sinotech engineers custom transformer solutions for high-altitude zones, extreme temperatures, corrosive atmospheres, and renewable energy applications with documented project success.
IEC, ANSI, and CE Certified Quality
Every Sinotech transformer meets stringent international standards. We provide full test reports and certification documentation with each shipment, ensuring regulatory compliance in your target market.
Rigorous Quality Control Process
Quality is built into every step of our manufacturing process. From silicon steel core selection to vacuum oil filling, Sinotech maintains strict controls to guarantee performance, safety, and long service life.
Contact Us Now
OEM Distribution Transformer Supplier
Our production lines support both standard power transformer models and fully custom designs, with annual capacity exceeding 15,000 transformer units. We have successfully executed OEM orders for clients in Southeast Asia, the Middle East, Africa, Latin America and more.
Our production lines support both standard power transformer models and fully custom designs, with annual capacity exceeding 15,000 transformer units. We have successfully executed OEM orders for clients in Southeast Asia, the Middle East, Africa, Latin America and more.
Sinotech welcomes inquiries from distributors, brand owners, and EPC contractors seeking a reliable power transformer manufacturer.
Urban Residential Network — Philippines
“Manila’s load profile is brutal — peak demand swings of 60% between afternoon and midnight. The Sinotech S13 units we installed in two residential substations have maintained stable output voltage throughout, and the no-load loss figures match exactly what was quoted.”












