Technical specifications
| Parameter | Value |
|---|---|
| Product Type | Oil-Immersed Power Transformer |
| Rated Capacity | 31500 kVA – 420000 kVA |
| Input Voltage | 220 kV / 230 kV |
| Output Voltage | 35 kV / 66 kV |
| Frequency | 50 / 60 Hz |
| Phase | Three |
| Coil Number | Multi Winding |
| Coil Structure | Fully Sealed Construction |
| Winding Material | Copper / Aluminium |
| Vector Group | Dyn11 / Yyn0 |
| Application | Power Distribution System |
| Standard | IEC / GB |
| Certification | IEC, CE, ISO9001, ISO14001, ISO45001, CQC, GOST, EAC |
| Service Life | 20 Years |
| Packing | Wooden Case |
| Package Size | 280 × 200 × 250 cm |
| Gross Weight | 5400 kg |
Specifications are based on the standard configuration. Final ratings, dimensions, materials and packaging are confirmed on the approved drawing and order confirmation.
Features and construction
- Large steel tank with horizontal cylindrical conservator (oil expansion) tank
- Multiple EHV porcelain bushings with corona/grading rings
- Dense finned radiator banks on both sides for efficient cooling
- Integrated control cabinet and roller base for on-site handling
- Fully sealed design minimizing oil oxidation and maintenance
Typical applications
Suited to 220/230kV transmission substations, regional grid interconnection, large industrial power supply, and utility-scale power distribution projects.
Customisation options
Capacity, voltage ratio, vector group, cooling method, tap changer, and certification tailored to project specification. Winding material (copper or aluminium) available on request.
Ordering information
Please confirm rated capacity, primary/secondary voltage, frequency, vector group, and applicable standard (IEC/GB) when ordering.
Specifications are based on the supplied product data. Final dimensions, materials, colors, and packaging are subject to the confirmed sample and order confirmation.
Standards and quality
Manufactured under an ISO 9001, ISO 14001 and ISO 45001 certified management system. Designs follow the IEC 60076 / IEC 62271 series as applicable, with ANSI/IEEE, GB and GOST variants available. Every unit passes routine testing before dispatch; type tests and customer or third-party witnessed factory acceptance tests can be arranged.
Frequently asked questions
What is the rated capacity of the 220/230kV Three-Phase Oil-Immersed Power Transformer (31500–420000kVA, 50/60Hz)?
The standard configuration is rated 31500 kVA – 420000 kVA at 50 / 60 Hz. Other ratings in the same family can be built to order — tell us the load and we will confirm the nearest standard rating.
What voltage ratio is available?
The standard unit is 220 kV / 230 kV input to 35 kV / 66 kV output. Voltage ratio, tapping range and vector group can be adjusted to your network; 50 Hz and 60 Hz designs are available.
Which standards and certifications apply?
The product is designed to IEC / GB. MARS operates an ISO 9001 / 14001 / 45001 certified factory and holds CE (ECM), UDEM, EAC and CQC approvals; every unit is routine-tested before dispatch and type or witnessed tests can be arranged.
Can this product be customised?
Capacity, voltage ratio, vector group, cooling method, tap changer, and certification tailored to project specification. Winding material (copper or aluminium) available on request.
What is the lead time and how is it shipped?
Packed in wooden case. Typical lead time is 25–45 days after drawing approval for distribution equipment and 60–90 days for power transformers and containerised systems. Shipment is by sea from Shanghai on EXW, FOB, CIF or DAP terms with a full document pack.
Enquire about this product
Tell us the rating, voltage ratio, frequency, quantity and destination. A MARS engineer replies with a technical proposal and quotation within one working day.












