Leilang Electric, an ISO 9001 certified manufacturer specializing in industrial power distribution solutions with over 15 years of transformer engineering expertise, presents our premium S11-250KVA 3-phase oil-immersed distribution transformer. Designed for rugged outdoor applications, this transformer delivers reliable power conversion from 10kV primary to 240V secondary voltage, supporting both 50Hz and 60Hz frequency systems worldwide.

• S11 Low-Loss Technology: Independently tested to deliver industry-leading energy efficiency with only 400W no-load loss and 3250W on-load loss, reducing long-term operational costs by up to 30% compared to older S9 series models.
• 100% Pure Copper Windings: Constructed with high-conductivity oxygen-free copper windings for superior mechanical strength, dynamic stability, and thermal performance, ensuring reliable operation under overload conditions.
• IEC 6007 Standard Compliance: Manufactured in strict accordance with international IEC 6007 standards, with additional CE and ISO certifications, guaranteeing global safety and performance compatibility.

Engineered for outdoor installation, this transformer features a robust steel enclosure with excellent impact resistance and high-temperature tolerance. The optimized heat sink design ensures efficient heat dissipation, while the clear oil level gauge provides real-time monitoring for simplified maintenance. It supports ONAN (natural air cooling) and ONAF (forced air cooling) operation modes, offering flexible overload capacity for varying load demands.

1. Superior Energy Efficiency: The S11 series design incorporates advanced core materials and precision manufacturing techniques to minimize no-load and load losses, delivering significant energy savings over the transformer's 30+ year service life.
2. Enhanced Mechanical & Thermal Stability: Pure copper windings provide excellent resistance to short-circuit forces and thermal stress, ensuring reliable operation even during peak load conditions.
3. Optimized Thermal Management: The scientifically arranged heat sink system maximizes heat dissipation area, enabling efficient cooling and extending insulation life.
4. User-Friendly Maintenance: The color-coded oil level gauge (red=low, blue=normal) allows quick visual inspection, while high-quality terminals with clear wiring instructions simplify installation and maintenance.
5. Rugged Outdoor Construction: The heavy-duty steel enclosure is designed to withstand harsh environmental conditions, including extreme temperatures, rain, and dust, making it ideal for outdoor industrial, commercial, and utility applications.

All Leilang Electric transformers undergo a rigorous 12-step quality control process, including:

• Raw material inspection and testing
• Winding resistance and insulation resistance tests
• Impedance and voltage ratio tests
• No-load and load loss measurements
• High-voltage withstand tests
• Final comprehensive performance verification

We support sample orders for quality verification and offer full OEM/ODM customization services, including custom voltage ratings, tap ranges, enclosure colors, and branding. With a monthly production capacity of 1,000 units and a standard lead time of 15-25 days, we can meet both small-scale and large project requirements. All products come with a 24-month warranty from the bill of lading date and lifetime technical support from our team of certified electrical engineers.

A: Our S11-250KVA transformer is manufactured in strict accordance with IEC 6007 international standards and holds CE and ISO 9001 certifications, ensuring compliance with global safety and performance requirements.

A: Copper windings offer higher electrical conductivity, better thermal stability, and superior mechanical strength compared to aluminum. This results in lower energy losses, longer service life, and improved resistance to short-circuit damage.

A: The S11 series reduces no-load losses by approximately 30% compared to traditional S9 series transformers. For a 250KVA transformer operating 24/7, this translates to over 2,600 kWh of annual energy savings, significantly lowering electricity costs.

A: Yes, it is specifically designed for outdoor use. The robust steel enclosure provides excellent protection against dust, moisture, and extreme temperatures, while the optimized cooling system ensures reliable operation in ambient temperatures ranging from -25°C to +40°C.

A: We maintain ISO 9001 certified manufacturing facilities. Each transformer undergoes multiple tests at every production stage, including material inspection, electrical performance testing, and final quality verification. All products are shipped with a detailed test report.

A: Yes, we provide comprehensive OEM/ODM customization services. We can modify voltage ratings, tap ranges, cooling methods, enclosure specifications, and add custom branding. Our engineering team will review and approve all custom designs before production.