Oil Immersed Transformer
Sinotech supplies oil immersed distribution transformers engineered for utilities, EPC contractors, and industrial projects that demand proven reliability and fast delivery. With over 30 years of combined manufacturing experience and IEC 60076 / IEEE C57.12 certified production, our transformers are built to perform in real-world conditions — from rural distribution networks to heavy industrial loads and renewable energy integration.
High-grade silicon steel cores reducing no-load losses significantly
Oxygen-free copper windings ensuring superior conductivity and durability
FR3 natural ester insulation option for fire safety applications
Corrosion-resistant tank coatings for coastal and mining environments
Custom Oil Immersed Transformer Manufacturer in China
Our oil immersed transformer portfolio covers 50kVA to 10,000kVA, with primary voltages from 10kV to 35kV and secondary outputs at 0.4kV or custom values. Standard models include S11, S13, and S20 energy-efficient series, designed to meet DOE efficiency levels where applicable. Every unit features high-grade silicon steel cores, oxygen-free copper windings, and premium mineral oil — materials that reduce no-load losses, extend transformer life, and lower total cost.
Primary Voltage
10kV to 35kV
Capacity
50kVA to 10,000kVA
Standards
ANSI/IEEE/DOE/CSA/AS
What Are the Standard Size of Sinotech S13 Oil Immersed 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 Oil-immersed Transformer
Custom Oil Filled Transformer Solutions
Custom engineering is where Sinotech stands apart. Whether you need non-standard impedance, dual-voltage taps, special BIL ratings for high-lightning zones, or corrosion-resistant tank coatings for coastal or mining environments, our engineering team delivers drawings within 5-7 working days.
We have successfully supplied transformers for projects in high-altitude regions above 3,000m, desert environments with 50°C temperature swings, and solar farms requiring low-noise and harmonic-tolerant designs.
Each transformer undergoes routine testing — including no-load loss, load loss, impedance, and temperature rise — before shipment. Test reports, CE/IEC certificates, and full export documentation are provided with every order.
Our Global Projects
66kV Oil Immersed Wind Power Transformer in Turkey
S11 – 1000/0 .4/33 Oil Immersed Transformer to Sri Lanka
Oil Immersed Distribution Transformer to Ghana
SZ11-20000/35 -10.5 Oil Transformers to Uganda
50 Oil-Filled Transformers to Jordan
S13 Oil Immersed Transformers to Argentina
Oil Immersed Transformer Application
Oil immersed transformers are the most widely used transformer type in modern power systems worldwide. Known for superior heat dissipation, high reliability, and proven technology, they serve critical roles across diverse industries. They are widely used in power distribution networks, industrial manufacuring, renewable energy systems, commercial buildings, infrastructure projects and more.
Power Distribution Networks
Renewable Energy System
Infrastructure Projects
High Quality, Reliable, and Long lasting Oil Transformer
Oil immersed transformers feature superior cooling performance which allows higher load capacity during extended operation. The established manufacturing process results in lower initial cost, while standardized maintenance procedures reduce long-term operational expenses. These transformers perform exceptionally well in outdoor and harsh environments, making them the preferred choice for demanding applications worldwide.
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.
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OEM Oil Immersed 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.
Sinotech welcomes inquiries from distributors, brand owners, and EPC contractors seeking a reliable power transformer manufacturer.
Solar Farm Integration — Chile
“Sinotech designed custom step-up transformers for our 50MW solar plant, handling 35kV output with low-noise requirements. The units passed local inspection without issues. Excellent engineering support.”
Global Clients
