The 250kVA 35kV to 0.4/0.22kV combined unit integrates a high-voltage load break switch and current-limiting fuse protection system with BF-type overcurrent release. It is designed for reliable protection, switching, and isolation in medium-voltage distribution networks, especially in compact substations and distribution transformer protection systems. This unit ensures safe operation of distribution transformers by providing fast fault interruption and overload protection.
The 250kVA 35kV oil immersed power transformer is designed for medium-voltage distribution networks, providing efficient voltage conversion from 35kV to 0.4kV/0.22kV. It adopts an oil-immersed cooling system to ensure stable performance, low loss, and long service life.
This transformer is widely used in substations, industrial power systems, and utility distribution networks where reliable and continuous power supply is required.
Zisheng are a professional 19+ years manufacturer in producing Oil-Immersed Transformers, Compact Substation, Pad Mounted Transformers, Pole Mounted Transformers and Dry Type Transformers. We own the certificates of ISO/CE/IEC 60076 and TUV Rheinland.
Transformers undergo rigorous FAT and type testing, support voltage/capacity customization. Welcome to consult for Catalog and Product. you can contact us at email [email protected].

| Item | Specification |
|---|---|
| Rated Capacity | 250kVA |
| Primary Voltage | 35kV |
| Secondary Voltage | 0.4kV / 0.22kV |
| Phase | Three-phase |
| Cooling Method | ONAN |
| Frequency | 50/60Hz |
| Standard | IEC 60076 compliant |
An oil immersed transformer is used for stepping down high voltage electricity to a lower usable voltage in power distribution systems. It is widely applied in substations, industrial plants, and utility networks.
This model is rated at 250kVA, with a primary voltage of 35kV and secondary voltages of 0.4kV / 0.22kV.
It uses ONAN (Oil Natural Air Natural) cooling, where insulating oil circulates naturally to dissipate heat efficiently.
Yes. This transformer is designed for outdoor installation, especially in substations and distribution networks.
It is manufactured according to IEC 60076 standards, and can also be customized to ANSI, IEEE, or GB standards based on project requirements.
Yes. We provide full customization, including:
Optional protection includes:
It is widely used in:
Under proper operation and maintenance, the transformer is designed for 20+ years of service life.
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