Product Overview
ZHONGXIN GENERAL (Sichuan Zhongxin General Electric Energy Co., Ltd.) manufactures the S11-4000/38.5 GY 4000 kVA three-phase outdoor oil-immersed power transformer. Rated 38.5 kV, Yd11 vector group, ONAN cooling, 7.10% impedance, compliant with GB1094.1.2-2013, GB1094.3-2017, GB/T6451-2023 and GB20052. All images on this page are real-shot photos from our Sichuan workshop. Contact us for datasheet and price.
This unit is designed for 35 kV-class medium-voltage networks, serving as a dedicated substation or main transformer for industrial plants, mining operations, hydropower stations and other large power supply projects. A Grade-1 high-efficiency version exceeding EU Commission Regulation No. 548/2014 and (EU) 2019/1783 is available, with copper or aluminium winding to suit your project budget and specification.
Technical Specifications
| Parameter | Value |
|---|---|
| Type | S11-4000/38.5 GY |
| Product Code | 1ST.710.3019.1 |
| Rated Capacity | 4000 kVA |
| Number of Phases | 3 Phase |
| Rated Frequency | 50 Hz |
| Vector Group | Yd11 |
| Cooling Method | ONAN |
| Service Condition | Outdoor |
| Insulation Level | HV LI 200 AC 85 kV / LV LI 60 AC 25 kV |
| Short-circuit Impedance | 7.10 % |
| No-load Loss | 3170 W |
| No-load Current | 0.19 % |
| Load Loss | 28357 W |
| Insulating Oil Weight | 1750 kg |
| Active Part Weight | 5090 kg |
| Total Weight | 9750 kg |
| Serial Number | NO.A240531 |
| Date of Manufacture | Nov 2024 |
| Standard Codes | GB1094.1.2-2013 / GB1094.3-2017 / GB/T6451-2023 / GB20052-2020 |
| Manufacturer | Sichuan Zhongxin General Electric Energy Co., Ltd. |
This unit ships to China GB 20052 Grade 3 energy efficiency as standard. Zhongxin General also produces Grade 1 and Grade 2 versions on request. Grade 1 units are built to technical standards equivalent to or higher than EU Commission Regulation No. 548/2014 and (EU) 2019/1783 Tier 1 and Tier 2, making them suitable for European and EU-aligned projects. Both copper and aluminium winding versions are manufactured in-house.
Engineering Considerations at 4000 kVA
A 4000 kVA, 38.5 kV unit is typically applied as a dedicated substation or main transformer for industrial plants, mining operations and hydropower stations. At 38.5 kV the HV rated current is approximately 60 A. The 7.10% impedance, 3,170 W no-load loss and 28,357 W load loss are routine-test values, so protection settings, busbar sizing and fault-level studies should be based on the unit’s test report rather than figures from a different capacity. For nearby capacity points, see our 2500 kVA and 5000 kVA oil-immersed transformer pages.
Manufacturing Process — Core to Finished Unit
Windings & Lead Wires
Windings are produced in batches and staged on pallets before core-coil assembly.
Lead-out wires are positioned and insulated to hold the clearances required by the LI 200 AC 85 kV (HV) and LI 60 AC 25 kV (LV) insulation levels.
Core-Coil Assembly
Joint geometry and clamping pressure during stacking carry straight through to the no-load loss figure on the nameplate, so core quality is checked at every stage.
Busbar Processing & Vacuum Drying
Copper busbars are fabricated in-house to prepare for connection and installation.
Vacuum drying removes moisture from the insulation system before tanking and oil filling, which is essential for long-term dielectric strength.
Finished Unit
The panel radiators provide the surface area for natural oil-and-air convection cooling at full load. There are no fans, pumps or auxiliary power draw, so maintenance is limited to periodic oil checks and inspection of bushings and fittings.
Why Zhongxin General — Manufacturer Advantages
Real photographs of the actual 4000 kVA unit. Every image on this page documents this specific capacity, from the nameplate through to dispatch at our Sichuan facility.
Full in-house production cycle. Winding, busbar processing, core-coil assembly, vacuum drying, oil treatment, tank assembly and routine testing all take place at our Xinjin District, Chengdu factory. Our oil-immersed transformer range spans 30 kVA to 100 MVA.
All energy efficiency grades available. Grade 1, 2 and 3 versions, with Grade 1 built to meet or exceed EU 548/2014 and 2019/1783 Tier 1/2. See how we handle EU documentation in our 1250 kVA dry-type transformer European export case study.
Copper and aluminium winding both available.
Full routine testing on every unit, test report as standard. No transformer leaves our factory without a complete routine test programme.
Documented project experience. A 5000 kVA, 33 kV transformer from our range was supplied to a hydropower station in Nepal — see the Chino Hydropower Station case study.
Applicable Standards & Testing
Routine tests (every unit): winding resistance measurement; voltage ratio and vector group verification; no-load loss and no-load current; load loss and short-circuit impedance; induced overvoltage withstand test; separate-source AC withstand test.
Type tests (reports available on request): temperature rise test; lightning impulse test.
Special tests (available on request): partial discharge measurement; sound level measurement; short-circuit withstand test.
All tests are conducted to IEC 60076 and GB 1094 / GB/T 6451. Factory Acceptance Test (FAT) with client witness is supported. Test reports and ITP documentation are provided with every order.
Typical Applications
The 4000 kVA oil-immersed transformer is commonly specified as a dedicated substation transformer for factories, mining operations and data centers, and as a step-up or step-down unit for hydropower and other power supply projects. Its Yd11 vector group and ONAN cooling make it a standard configuration for grid connection in markets following GB or IEC standards. For projects that need an integrated, factory-tested delivery, it can also be paired with our prefabricated substation solutions.
Dispatch
At a total weight of 9,750 kg, each unit requires a heavy-duty flatbed for road transport. Units are crane-loaded, blocked and secured to our standard transport procedure. For export, we offer nitrogen sealing of the tank and export-grade wooden crating.
Inquire About 4000 kVA Oil-Immersed Transformer
Need a quotation, technical datasheet or Factory Acceptance Test arrangement for the 4000 kVA oil-immersed transformer? Tell us your grid voltage, required LV output, frequency, efficiency grade and any special site conditions, and we will configure the right unit for your project.
Contact Us for Price & Datasheet
About Zhongxin General — Oil-Immersed Transformer Manufacturer & Factory
Zhongxin General (Sichuan Zhongxin General Electric Energy Co., Ltd.) is a China-based manufacturer and factory specialising in oil-immersed and dry-type power transformers, HV/MV/LV switchgear, prefabricated substations and energy storage systems. Headquartered in Xinjin District, Chengdu, the company holds National “Little Giant” Enterprise status and National High-Tech Enterprise certification. Every transformer we manufacture undergoes full routine testing to IEC 60076 or GB 1094 before dispatch, with test reports issued as standard documentation.
