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Certified transformers (≤35kV), smart substations & PV-storage systems — engineered with 9 patents. Precision-built for renewable integration and grid reliability. Request specs
S11-100/10/0.4 oil-immersed transformers
The oil immersed transformers produced by our company are suitable for power systems with an AC frequency of 50Hz and a rated working voltage of 35kV and below. They are used in various fields such as industry, agriculture, transportation, and urban communities, and are the main substation equipment in transmission and distribution networks. This series of products has the following technical characteristics:
S11-100/35/0.4 oil-immersed transformers
The oil immersed transformers produced by our company are suitable for power systems with an AC frequency of 50Hz and a rated working voltage of 35kV and below. They are used in various fields such as industry, agriculture, transportation, and urban communities, and are the main substation equipment in transmission and distribution networks. This series of products has the following technical characteristics:
S11-1000/10/0.4 oil-immersed transformers
The oil immersed transformers produced by our company are suitable for power systems with an AC frequency of 50Hz and a rated working voltage of 35kV and below. They are used in various fields such as industry, agriculture, transportation, and urban communities, and are the main substation equipment in transmission and distribution networks. This series of products has the following technical characteristics:
S11-1000/35/0.4 oil-immersed transformers
The oil immersed transformers produced by our company are suitable for power systems with an AC frequency of 50Hz and a rated working voltage of 35kV and below. They are used in various fields such as industry, agriculture, transportation, and urban communities, and are the main substation equipment in transmission and distribution networks. This series of products has the following technical characteristics:
S11-1000/35/10.5 oil-immersed transformers
The oil immersed transformers produced by our company are suitable for power systems with an AC frequency of 50Hz and a rated working voltage of 35kV and below. They are used in various fields such as industry, agriculture, transportation, and urban communities, and are the main substation equipment in transmission and distribution networks. This series of products has the following technical characteristics:
Application scenario
Designed for Critical Power Infrastructure
Whether used in EPC projects or grid upgrades, our transformers deliver reliability, high efficiency, and compliance with international standards.
Industrial Plants
Residential Communities
Urban Distribution Networks
Power Grid Projects
Solar PV Systems
Product Features
Key Features of This Product Line
Built for industrial and utility-scale applications, our products feature high-quality materials, low energy loss, and robust insulation. Each unit is designed and tested to GB/IEC standards, with support for custom voltage levels, tap changers, and protection grades. From core processing to final testing, we ensure long-term reliability and project-specific adaptability.
On-load / off-load tap changers
Transformer ratings up to 35kV
Cabinet design & layout drawings
Site-matching size & interface
Customized cooling / protection level
PV inverter integration & full pre-wiring
Available Models & Technical Specifications
Available Models & Technical Specifications
We offer a wide range of oil-immersed power transformers for medium and high-voltage applications. All models support customization of voltage ratio, capacity, tap changer type, and protection grade.
| Model Series | Rated Capacity Range | Voltage Class | Cooling Method | Tap Changer | Application Scope |
|---|---|---|---|---|---|
| S11 Series | 30 kVA – 1600 kVA | 6kV / 10kV / 11kV | ONAN | NLTC | Distribution & Industrial |
| S13 Series | 200 kVA – 2500 kVA | 6kV / 10kV / 11kV | ONAN | NLTC | Energy Efficient Projects |
| SZ11 Series | 1600 kVA – 10000 kVA | 35kV / 20kV / 10.5kV | ONAN/ONAF | OLTC | Power Substations |
| SZ22 Series | 4000 kVA – 31500 kVA | 35kV / 10.5kV | ONAN/ONAF | OLTC | Grid Upgrades & EPC |
| SZ20 Series | 10000 kVA – 40000 kVA | 35kV / 10.5kV | ONAN/ONAF | OLTC | Industrial & Power Grid |
Notes:
All transformer models are available in Dyn11 or YNd11 vector groups
Impedance, insulation level, protection class, and loss levels follow IEC/GB standards
Fully customizable per client drawings and project needs
We support transformer customization including
Custom Design to Match Your Project Requirements
Voltage class, capacity, vector group
Tap changer type (OLTC/NLTC)
Custom paint, nameplate, cable bushing
Packaging and labeling for export
Special insulation or protection level
We support transformer customization including
Factory Tested. Globally Delivered.
In-house vacuum drying, impulse testing, and heat run facilities
100% testing before shipment
CE / ISO9001 / ISO14001 certified
Export packaging + 3rd party inspection supported
Frequently Asked Questions
We understand that as a professional buyer, you may have technical, logistical, or customization concerns. Below are answers to some of the most frequently asked questions to help you make informed decisions.
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Q Can you provide technical drawings and specifications before placing an order?A
Yes. Once we confirm your basic requirements such as rated voltage, capacity, application environment, and local standards (e.g., IEC, GB, ANSI), our engineering team will provide you with detailed technical drawings, wiring diagrams, and specification sheets within 1–3 working days. We also support modifications until the design fully meets your project needs.
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Q What are the advantages of your oil-immersed transformers over others?A
Our oil-immersed transformers are manufactured with high-quality silicon steel sheets, oxygen-free copper windings, and advanced vacuum oil-filling technology. Compared to conventional models, our S13 and S11 series offer lower no-load loss and noise, better thermal performance, and longer service life. We also provide on-load tap-changing options (OLTC) for intelligent voltage regulation in grid systems.
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Q Can you customize transformers according to specific project requirements?A
Yes. We support full OEM and ODM services. Whether it’s for special voltage ratios (e.g., 35/10.5kV), frequency (50Hz or 60Hz), tropical climate resistance, or anti-corrosion coatings for coastal applications, we can fully customize the transformer’s design, protection level (IP), enclosure, and installation interface. Drawings and technical discussions are available before production.
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Q What international standards do your transformers comply with?A
Our transformers are manufactured in strict accordance with IEC 60076, GB/T 6451, and other relevant international and national standards. Upon request, we can also meet IEEE, ANSI, or DIN standards. Our factory has passed ISO9001:2015, and our products are certified by CE, CCC, or third-party inspection agencies such as SGS or BV when needed.
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Q How do you ensure product quality and performance before shipment?A
Each transformer undergoes a full set of type tests and routine tests before delivery, including insulation resistance, transformer ratio, voltage withstand test, no-load and load loss test, oil leakage inspection, and temperature rise test. We use automatic vacuum oil filling and full-sealing technology to guarantee long-term operation stability.
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Q What is the typical delivery time and how is packaging handled?A
Standard production lead time is 15–30 days depending on model and quantity. All oil-immersed transformers are securely packed in steel-framed wooden crates with anti-vibration protection. For overseas shipments, we ensure moisture-proof wrapping and reinforced base support for container loading. On-site installation guides and technical support can also be arranged if required.
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Q Do you offer installation, commissioning, or technical support overseas?A
Yes. For bulk orders or EPC projects, we offer remote video support, on-site engineer dispatch, and commissioning guidance. Our technical team is experienced with overseas grid requirements and can assist with documentation, wiring diagrams, and field troubleshooting. We also provide long-term spare parts supply and maintenance guidance.
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