When your project demands reliable, high-performance transformers at scale, partnering with the right bulk transformer supplier is critical. FIJ TECH is a leading manufacturer and exporter of power and distribution transformers, serving utilities, EPC contractors, and commercial developers across 40+ countries. Our factory combines advanced manufacturing, rigorous testing, and deep engineering expertise to deliver transformers that meet international standards and perform flawlessly in the field.
From 30kVA distribution units to 31,500kVA power transformers, we offer a comprehensive range of voltage ratings, cooling configurations, and enclosure options. Whether you need oil-immersed units for substations or dry type transformers for indoor installations, FIJ TECH ensures every unit is built to spec, tested per IEC 60076, and backed by comprehensive documentation.
Why Procurement Managers Choose FIJ TECH as Their Bulk Supplier
Bulk transformer procurement involves more than just price per unit. You need a partner who can guarantee consistent quality, on-time delivery, and technical compliance. FIJ TECH has established a reputation for reliability, with a dedicated export team that understands the complexities of international shipping, documentation, and certification.
Our factory is ISO 9001:2015 certified, and all transformers are tested in accordance with IEC 60076 (Power Transformers) and IEC 60076-11 (Dry Type Transformers). We also offer compliance with IEEE C57.12.00, GB 1094 (Chinese National Standard), and GB/T 17467 for compact substations. For European projects, CE marking is available, and VDE certification can be arranged on a project basis.
- Voltage levels: 6kV, 10kV, 11kV, 20kV, 33kV, 35kV
- Capacity range: 30kVA to 2500kVA (standard), up to 31,500kVA (custom)
- Frequency: 50Hz or 60Hz
- Cooling methods: ONAN, ONAF (oil-immersed); AN, AF (dry type)
- Efficiency compliance: GB 20052-2020 (China), EU EcoDesign Tier 2, DOE 2016 (US)
Comprehensive Transformer Range for Every Application
Oil-Immersed Distribution Transformers
Our oil-immersed transformers are the workhorses of electrical distribution networks. Built with high-grade grain-oriented silicon steel cores and low-loss winding materials, they deliver excellent efficiency and long service life. Available in both sealed and conservator types, these units are ideal for outdoor substations, industrial facilities, and utility grids.
We supply oil transformers from 30kVA to 2500kVA in standard ranges, with custom designs for higher capacities. All units are available in 50Hz or 60Hz versions, and we can accommodate various impedance voltages (uk%) to match your switchgear and protection settings.
Explore our oil transformer category for detailed specifications and options.
Dry Type Transformers for Indoor and Safety-Critical Applications
For projects where fire safety, space, or environmental concerns are paramount, our cast resin dry type transformers offer a clean, safe solution. With no oil, these units require no containment pits and are maintenance-free in normal operation. They are ideal for commercial buildings, hospitals, data centers, and underground substations.
We manufacture dry type transformers from 30kVA to 2500kVA with voltages up to 35kV, featuring F-class or H-class insulation and IP21 to IP54 enclosures. Our units comply with IEC 60076-11 and are available with CE marking for European projects.
View our dry transformer category for more details.
Technical Comparison: Oil vs. Dry Type Transformers
| Parameter | Oil-Immersed | Dry Type (Cast Resin) |
|---|---|---|
| Cooling Method | ONAN / ONAF | AN / AF |
| Installation | Outdoor / Indoor (with containment) | Indoor only |
| Fire Risk | Moderate (oil) | Low (self-extinguishing) |
| Typical Voltage | Up to 35kV | Up to 35kV |
Choosing the right type depends on your site conditions, safety requirements, and budget. Our engineers can help you evaluate the trade-offs and select the most cost-effective solution.
Factory Case Study: 35kV SCB14 Dry Type Transformer for Middle East Commercial Complex
Industry: Commercial Building
Country: Saudi Arabia
Product: SCB14-2500/35 (35kV / 0.4kV, 2500kVA)
A major commercial complex in Saudi Arabia required a reliable transformer for their basement substation. The challenge was limited indoor installation space and strict fire safety regulations that prohibited oil-filled equipment in the building. FIJ TECH supplied a cast resin dry type transformer with F-class insulation and IP31 enclosure, which met all safety and space requirements.
The transformer was tested to IEC 60076-11 and CE standards, ensuring full compliance with local regulations. The client reported, “The dry type transformer fits our basement substation perfectly. No oil containment needed.” This project demonstrates our ability to provide tailored solutions for demanding environments.
Technical Engineering: Voltage Drop & Short-Circuit Impedance Check
When procuring transformers in bulk, it’s essential to verify that the impedance voltage (uk%) aligns with your system’s short-circuit withstand capability and voltage regulation. Here’s a practical guide:
- Step 1: Verify transformer impedance voltage (uk%) matches switchgear breaking capacity. For example, a typical 10kV distribution transformer has uk = 4%.
- Step 2: Calculate voltage drop under load using the formula: ΔU = β × uk × (cosφ + sinφ × tanθ), where β is the load factor, cosφ is the power factor, and tanθ is the reactive factor.
- Step 3: Ensure that the voltage drop at full load stays below 5% at motor terminals to maintain equipment performance.
For a 2500kVA transformer with uk=6%, β=0.8, cosφ=0.8 (tanθ=0.75), the voltage drop would be ΔU = 0.8 × 6 × (0.8 + 0.6 × 0.75) = 0.8 × 6 × 1.25 = 6%, which is slightly above the 5% limit. In such cases, you may need to select a transformer with a lower impedance or adjust the tap changer. Our engineers can assist with these calculations for your specific project.
Quality Assurance and International Certifications
Every FIJ TECH transformer undergoes routine and type testing as per IEC 60076, including measurement of winding resistance, no-load loss, load loss, impedance, and dielectric tests. We also offer optional tests such as partial discharge measurement and temperature rise tests.
Our certifications include:
- ISO 9001:2015 (Quality Management System)
- IEC 60076 (Power Transformers)
- IEC 60076-11 (Dry Type Transformers)
- IEEE C57.12.00 (US Standards)
- GB 1094 (Chinese National Standard)
- GB/T 17467 (Compact Substations)
- CE (European Conformity)
- VDE (Germany, project basis)
These certifications ensure that our transformers are accepted by utilities and inspectors worldwide, reducing your project risk and administrative overhead.
Why FIJ TECH Is Your Ideal Bulk Transformer Supplier
FIJ TECH has a dedicated export team that handles everything from technical clarification to shipping documentation. We offer flexible payment terms, production lead times as short as 4-6 weeks for standard units, and after-sales technical support. Our factory is equipped with advanced winding machines, vacuum casting equipment, and a full testing laboratory.
We understand that bulk orders require careful coordination. That’s why we provide pre-shipment inspection reports, test certificates, and detailed CAD drawings for every order. Our customers in over 40 countries rely on us for consistent quality and dependable delivery.
Visit our homepage to learn more about our capabilities, or browse our products overview to see the full range of transformers we offer.
Get a Competitive Quote for Your Bulk Transformer Needs
Ready to secure a reliable bulk transformer supplier for your next project? Contact FIJ TECH today with your specifications, including voltage, capacity, frequency, and any special requirements. Our engineering team will respond within 24 hours with a detailed quotation, technical datasheet, and delivery schedule. Let us help you power your project with confidence.
Request your quote now and experience the FIJ TECH difference.