250kVA 10kV to 0.4kV Oil-Immersed Distribution Power Transformer for Rural Electrification

The Factory Price S11-250kVA 10kV to 0.4kV Distribution Power Transformer is a high-performance, three-phase oil-immersed unit specifically engineered for rural electrification and agricultural power grids. As an industry-standard step-down transformer, the S11 series balances cost-efficiency with exceptional reliability. Whether for remote village power supply, irrigation systems, or small industrial zones, this 250kVA unit provides a stable 400V/415V output to ensure the longevity of downstream electrical equipment.

• Cost-Effective Energy Savings: The S11 core design significantly reduces no-load losses compared to S9 models, providing a high ROI for long-term rural infrastructure.
• Ruggedized for Rural Environments: Designed for pole-mounted or ground-mounted installation, featuring high-durability anti-corrosion coating for outdoor use.
• International Standards Compliance: Fully compliant with IEC 60076, CE, and ISO standards, ensuring seamless integration into global tenders and EPC projects.

• Core Material: Built with high-permeability, cold-rolled grain-oriented (CRGO) silicon steel sheets for reduced magnetic hysteresis.
• Cooling System: Natural Oil Natural Air (ONAN) cooling with high-efficiency corrugated radiator fins for optimal heat dissipation.
• Insulation Class: Class A insulation with high-dielectric strength mineral oil to prevent internal arcing.
• Tapping Range: Equipped with an off-circuit tap changer (e.g., ±5% or ±2x2.5%) to adjust to fluctuating input voltages from the grid.
• Sealing Technology: Vacuum-filled oil process ensures zero air bubbles, enhancing the aging resistance of the insulating oil.

Core Strengths: In sandy and dusty regions (like many African countries), dust accumulation on seals combined with high temperatures often leads to oil leakage and insulating oil degradation, causing premature transformer failure.

Our Solution:

• Double-Gasket Hermetic Sealing: We use high-quality nitrile rubber gaskets and a fully sealed tank design to isolate oil from external dust and moisture.
• Enhanced Surface Treatment: A multi-layer, electrostatic powder coating prevents sand abrasion and UV-induced paint peeling.
• Leak-Proof Bushings: High-creepage distance porcelain bushings with reinforced sealing collars prevent sand from penetrating the connection points, drastically reducing maintenance frequency.