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Product Overview
About Oil-Immersed Transformer
Oil-immersed transformers are the backbone of modern power distribution, known for their superior cooling, high insulation strength, and long-term reliability. At Baitong Electric, we provide high-performance S9 S11 and S13 series transformers to meet diverse industrial needs.
- Low Loss & High Efficiency
- Excellent Heat Dissipation
- Maintenance-Free Structure
- High Short-Circuit Resistance
- Long Operational Lifespan
- Reliable Protection
- 24/7 Available to Service
Our manufacturing process ensures that every unit—from the small 30kVA to the large 2500kVA—meets the highest quality standards:
100% Pure Copper Windings: For maximum conductivity and heat resistance.
Low-Loss Silicon Steel Cores: Reducing operational costs for the end-user.
Rigorous Testing: Each unit undergoes ratio, insulation, and load-loss testing before leaving our factory.
s11 series of oil-immersed transformer
Key Technical Advantages:
- Energy Efficiency: Compared to the older S9 series, S11 transformers reduce no-load loss by approximately 30%, helping you lower operational costs from day one.
- Premium Materials: We utilize 100% high-purity copper windings and high-permeability silicon steel cores to ensure maximum conductivity and minimum heat generation.
- Versatile Voltage Options: Available in 10kV, 20kV, and 35kV classes, with capacities ranging from 30kVA to 2500kVA to suit any project scale.
- Durable Protection: Each unit is finished with high-quality anti-corrosion paint, making it ideal for harsh outdoor environments, including high-humidity or high-altitude regions.
Tech data of 10kV S11-M series distribution transformer
| Rated Capacity (kVA) | High-voltage (kV) | Low-voltage (kV) | Connection Method | No-load Loss (kW) | Load Loss 75℃ (kW) | No-load Current (%) | Impedance Voltage (%) | Machine Weight (kg) | Oil Weight (kg) | Total Weight (kg) | Outline Dimension (LxWxH mm) | Gauge Vertical/Horizontal (mm) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 30 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.1 | 0.6 | 2.1 | 4 | 185 | 70 | 325 | 750×490×970 | 450/350 |
| 50 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.13 | 0.87 | 2 | 4 | 255 | 85 | 420 | 770×550×1030 | 450/350 |
| 63 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.15 | 1.04 | 1.9 | 4 | 280 | 95 | 480 | 800×600×1040 | 450/380 |
| 80 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.18 | 1.25 | 1.8 | 4 | 320 | 100 | 535 | 810×680×1060 | 450/430 |
| 100 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.2 | 1.5 | 1.6 | 4 | 380 | 110 | 615 | 820×680×1100 | 550/450 |
| 125 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.24 | 1.8 | 1.5 | 4 | 440 | 115 | 690 | 1070×700×1150 | 550/470 |
| 160 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.28 | 2.2 | 1.4 | 4 | 510 | 130 | 800 | 1120×700×1220 | 550/500 |
| 200 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.34 | 2.6 | 1.3 | 4 | 610 | 150 | 935 | 1160×720×1255 | 550/520 |
| 250 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.4 | 3.05 | 1.2 | 4 | 720 | 190 | 1110 | 1200×760×1310 | 650/550 |
| 315 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.48 | 3.65 | 1.1 | 4 | 835 | 200 | 1270 | 1210×780×1320 | 650/550 |
| 400 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.57 | 4.3 | 1 | 4 | 1010 | 240 | 1540 | 1340×880×1360 | 650/550 |
| 500 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.68 | 5.1 | 1 | 4 | 1170 | 260 | 1765 | 1360×890×1430 | 750/600 |
| 630 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.81 | 6.2 | 0.9 | 4.5 | 1375 | 320 | 2095 | 1560×1020×1410 | 850/660 |
| 800 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.98 | 7.5 | 0.8 | 4.5 | 1620 | 365 | 2470 | 1640×1060×1500 | 850/660 |
| 1000 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 1.15 | 10.3 | 0.7 | 4.5 | 1780 | 405 | 2780 | 1720×1160×1540 | 850/660 |
| 1250 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 1.36 | 12.8 | 0.6 | 4.5 | 2065 | 560 | 3395 | 1790×1190×1740 | 850/660 |
| 1600 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 1.64 | 14.5 | 0.6 | 4.5 | 2470 | 650 | 3990 | 1830×1210×1850 | 850/700 |
| 2000 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 1.96 | 19.8 | 0.6 | 4.5 | 2700 | 695 | 4460 | 2190×1900×1950 | 820/820 |
| 2500 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 2.31 | 23 | 0.6 | 4.5 | 3230 | 870 | 5330 | 2240×1940×1980 | 1070/1070 |
s13 series of oil-immersed transformer
The S13 Series represents the next generation of energy-saving power distribution technology. Engineered to outperform the standard S11 models, the S13 series is the ideal choice for projects requiring superior energy efficiency, reduced operational costs, and environmental sustainability.
Key Advantages of the S13 Series
Ultimate Energy Savings: The S13 series is designed with advanced magnetic circuit optimization. Compared to the S11 series, it reduces no-load loss by 25%–30%, significantly lowering electricity waste during standby.
Ultra-Low No-Load Current: By utilizing high-permeability cold-rolled silicon steel, the no-load current is reduced by up to 70%–80%, improving the overall power factor of the grid.
Maintenance-Free Reliability: Featuring a hermetically sealed (M-type) corrugated tank design, the transformer oil is completely isolated from the atmosphere. This prevents oxidation and moisture, ensuring a service life of over 20 years without the need for regular oil changes.
Quiet Operation: Optimized core stacking technology significantly lowers vibration and noise levels, making it suitable for noise-sensitive residential and commercial areas.
Tech data of 10kV S13, S13-M series distr bution trabsformer
| Rated Capacity (kVA) | Voltage Group High-voltage (kV) | Voltage Group Low-voltage (kV) | Connection Method | Dissipation No-load (kW) | Dissipation Load 75℃ (kW) | No-load Current (%) | Impedance Voltage (%) | Machine Weight (kg) | Oil Weight (kg) | Gross Weight (kg) | Outline Dimension Omniseal (LxWxH mm) | Outline Dimension Un-omniseal (LxWxH mm) | Gauge Vertical/Horizontal (mm) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 30 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.08 | 0.6 | 2.1 | 4 | 170 | 55 | 260 | 670x560x870 | 1070x560x950 | 450/340 |
| 50 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.1 | 0.87 | 2 | 4 | 230 | 65 | 340 | 750x600x920 | 1150x600x1000 | 450/380 |
| 63 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.11 | 1.04 | 1.9 | 4 | 260 | 70 | 400 | 710x620x970 | 1110x620x1050 | 450/380 |
| 80 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.13 | 1.25 | 1.8 | 4 | 310 | 85 | 460 | 770x640x1010 | 1170x640x1090 | 450/430 |
| 100 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.15 | 1.5 | 1.6 | 4 | 360 | 90 | 525 | 955x620x1020 | 1255x620x1100 | 550/450 |
| 125 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.17 | 1.8 | 1.5 | 4 | 425 | 95 | 600 | 1035x675x1040 | 1340x675x1120 | 550/470 |
| 160 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.2 | 2.2 | 1.4 | 4 | 480 | 115 | 705 | 1105x675x1065 | 1410x730x1145 | 550/520 |
| 200 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.24 | 2.6 | 1.3 | 4 | 580 | 135 | 830 | 1170x765x1115 | 1460x765x1235 | 550/520 |
| 250 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.29 | 3.05 | 1.2 | 4 | 670 | 145 | 960 | 1225x820x1140 | 1510x820x1260 | 650/550 |
| 315 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.34 | 3.65 | 1.1 | 4 | 775 | 190 | 1135 | 1345x890x1205 | 1590x890x1330 | 650/550 |
| 400 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.41 | 4.3 | 1 | 4 | 940 | 220 | 1365 | 1450x935x1240 | 1620x900x1380 | 600/600 |
| 500 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.48 | 5.1 | 1 | 4 | 1155 | 240 | 1595 | 1515x970x1280 | 1785x970x1420 | 750/600 |
| 630 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.57 | 6.2 | 0.9 | 4 | 1310 | 275 | 1935 | 1595x1040x1315 | 1830x1040x1460 | 850/660 |
| 800 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.7 | 7.5 | 0.8 | 4 | 1495 | 355 | 2345 | 1765x1170x1350 | 2130x1170x1570 | 850/660 |
| 1000 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.83 | 10.3 | 0.7 | 4 | 1705 | 400 | 2620 | 1855x1255x1490 | 2160x1250x1770 | 850/660 |
| 1250 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 0.97 | 12.8 | 0.6 | 4.5 | 1990 | 460 | 3050 | 1885x1270x1590 | 2170x1280x1875 | 850/660 |
| 1600 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 1.17 | 14.5 | 0.6 | 4.5 | 2345 | 660 | 3690 | 1905x1280x1735 | 2200x1280x1965 | 850/700 |
| 2000 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 1.7 | 17.5 | 0.6 | 4.5 | 2470 | 710 | 4110 | - | 2170x1630x2220 | 820/820 |
| 2500 | 11, 10.5, 10, 6.3, 6 | 0.4 | Yyno or Dyn11 | 2.04 | 21 | 0.6 | 4.5 | 2960 | 810 | 4980 | - | 2200x1740x2250 | 1070/1070 |
Service Conditions & Installation Environment：
To ensure the optimal performance and longevity of our oil immersed transformers, the following standard service conditions should be maintained. For installations in specialized environments, please contact our technical team for custom-engineered solutions.
Ambient Temperature Limits:
Maximum Ambient Temperature: +40°C
Daily Average Maximum: +30°C
Annual Average Maximum: +20°C
Minimum Ambient Temperature: -25°C
Note: For projects in regions with extreme temperature transformer operation requirements, we provide enhanced cooling systems.
Altitude and De-rating:
Standard Altitude: Up to 1,000 meters above sea level.
High Altitude Customization: For installations exceeding 1,000m, such as in high-altitude mining or mountainous regions, we apply transformer de-rating for altitude and adjust insulation clearances according to IEC standards.
Installation Environment & Air Quality:
Installation Slope: The vertical inclination of the installation site must not exceed 3°.
Atmospheric Conditions: The site should be free from significant dust, explosive gases, or corrosive chemical vapors.
Corrosion Resistance: For coastal or high-humidity areas, we recommend our corrosion-resistant oil transformer with an omniseal tank design to prevent oxidation and moisture ingress.
Power Supply Quality:
Voltage Waveform: The power supply voltage waveform should be a close approximation of a sine wave.
Phase Balance: For three-phase transformers, the supply voltage and load should remain basically balanced to ensure three-phase voltage stability.
Specialized Service Conditions:
If your project involves any of the following, please specify during the inquiry for customization service:
Highly seismic zones (earthquake-prone areas).
Severe salt spray environments (Offshore/Coastal).
Exceptional space constraints requiring specialized outline dimensions.
Technical FAQ & Support:
What is the difference between the S11 and S13 series of oil-immersed transformers?
The main difference lies in energy efficiency. The S13 series utilizes more advanced magnetic materials and structural designs, resulting in no-load losses that are typically more than 25% lower than those of the S11 series. This means that while the S13 has a slightly higher initial cost, it significantly reduces electricity costs over the long term and better aligns with modern green energy standards.
What does the “Z” in the SZ11 series stand for, and what are its advantages?
“Z” stands for On-load Tap Changing (OLTC). Unlike the standard S11, which features off-load tap changing, the SZ11 can automatically adjust voltage taps without interrupting the power supply. This is crucial for industrial parks or large factories where grid voltage fluctuations are severe and the demand for power stability is extremely high.
Why choose the Omniseal design?
Our fully sealed oil-immersed transformers (such as the S13 series) eliminate the oil reservoir, completely isolating the oil from the air. This effectively prevents moisture and oxygen from entering and causing the insulating oil to age, thereby eliminating the need for core-removal maintenance throughout the transformer’s normal service life and significantly reducing long-term operational and maintenance costs for our overseas customers.
Customized Solutions/Service
This Service Include
- Precision Customization
- Factory Test Report
- 2-Year Warranty
- Technical Installation Guide
Contact Our Transformer Experts
Request a customized high-efficiency transformer solution or get immediate support from our global engineering team.