Go Green, Stay Safe: Our Opening Winding Dry Type Transformers Offer Eco-friendly and Secure Energy Solutions!
01 General
1.1 Project Description
The 630 kVA opening winding dry type transformer was delivered to South Africa in 2024; the rated power of the transformer is 630 kVA. The primary voltage of the transformer is 11 kV and secondary voltage is 0.55 kV. SCOTECH’s dry type power transformer have the characteristics of strong short-circuit resistance, small maintenance workload, high operating efficiency, small size, low noise, and are often used in places with high performance requirements such as fire prevention and explosion prevention. Safe, fireproof, no pollution, can be directly operated in high load power. The product is H class, the insulation material is C class, the short-circuit resistance is strong, and the safety performance is high. Good heat dissipation performance, strong overload capacity, short-time super-capacity operation under forced air cooling. High quality and high permeability silicon steel, multi-step process, bass noise reduction, low no-load loss. SCOTECH produces dry type power transformer with strong climate adaptability, moisture, salt spray and corrosion resistance, strong weather resistance and long service life. Using multiple technologies, effectively suppress harmonic content, filter harmonics, and prolong motor life.
Our 630 kVA opening winding dry type transformer was designed with advanced technology and adopts high quality material and components, which result in reliable quality and long operation time.
We ensure that each one of our delivered units has undergone rigorous full acceptance testing. We provide one-package service from consulting, quoting, manufacturing, installation, commissioning, training to after-sales services. Our products are now operating in more than 50 countries in the world. We aim to be your most reliable supplier as well as your best partner in business!
1.2 Technical Specification
630 kVA dry type power transformer specification and data sheet
| Delivered to | South Africa |
| Year | 2024 |
| Model | 630KVA-11/0.55KV |
| Type | Opening winding dry type transformer |
| Standard | IEC60076 |
| Rated Power | 630KVA |
| Frequency | 50HZ |
| Phase | 3 |
| Cooling Type | AN/AF |
| Primary Voltage | 11KV |
| Secondary Voltage | 0.55KV |
| Winding Material | Aluminum |
| Impedance | 6% |
| Tap Changer | NLTC |
| Tapping Range | ±2*2.5%@primary side |
| No Load Loss | 1.1KW |
| On Load Loss | 8.3KW |
| Accessories | Standard Configuration |
| Insulation level | H |
| Basic impulse lighting withstand voltage-primary side (BIL) | 75KV |
| Power frequency withstand voltage-primary side | 35KV |
| Basic impulse lighting withstand voltage-secondary side (BIL) | / |
| Power frequency withstand voltage-secondary side | 3KV |
| Winding temperature rise @ rated service condition | 100K |
1.3 Drawings
630 kVA dry type power transformer diagram drawing and size.
02 Manufacturing
2.1 Core
| The role of VPI dry type transformer core is to form a magnetic circuit. In order to reduce eddy current loss, the core is made of thin silicon steel sheet staggered. The surface of the silicon steel sheet is coated with insulating paint and oxidized to form an insulating layer. The core is mainly composed of an iron core body, fasteners and insulating parts. The core adopts multi-step process through the core positioning structure. Under various working conditions, the core has no transverse and longitudinal displacement. |  |
2.2 Winding
 | The winding of the dry type power transformer is made of fireproof class H enamelled wire, which has excellent performance and heat dissipation, and is arranged tightly and evenly. When winding, cylindrical winding is used, and the low-voltage winding is close to the core in order to insulate it from the core. The high voltage winding is centrally enclosed outside the low voltage winding. The windings are usually of cascading or helical construction to reduce magnetic leakage and improve the efficiency of the transformer. The winding of the open winding dry type transformer is not limited by the closed shell and can dissipate heat freely in the air, so its heat dissipation performance is relatively good. This design is suitable for use in places with higher ambient temperatures or better ventilation conditions. |
2.3 Final Assembly
| Insulation Treatment: Apply insulation materials and check the integrity of the insulation. Wiring: Install terminals and connect wires correctly. Housing Assembly: Install the housing and ensure proper sealing. |  |
03 Testing
| No. | Test Item | Unit | Acceptance Values | Measured Values | Conclusion | |
| 1 | Measurement of winding resistance | / | Maximum resistance unbalance rate Line resistance:≤2% | HV (line) | LV (line) | Pass |
| 0.26% | 0.65% | |||||
| 2 | Measurement of voltage ratio and check of phase displacement | / | The tolerance of voltage ratio on the principal tapping: ±1/10 Connection symbol: Dyn11 | -0.05% ~ 0.14% Dyn11 | Pass | |
| 3 | Measurement of Short-circuit Impedance and Load Loss | / kW kW | t:120℃ Z%: measured value Pk: measured value Pt: measured value | 6.14% 5.59 7.243 | Pass | |
| 4 | Measurement of No-load Loss and Current at 90% and 110% of rated voltage | / kW | I0:: provide measured value P0: provide measured value | 90% Ur | 110% Ur | Pass |
| 0.342% | 0.418% | |||||
| 0.951 | 1.162 | |||||
| 5 | Applied Voltage Test | / | HV: 35kV 60s LV: 3kV 60s | No collapse of the test voltage occurs | Pass | |
| 6 | Induced Voltage Withstand Test | / | Applied voltage (kV): 2 Ur Induced voltage (kV): 1.1 Duration(s):40 Frequency (HZ): 150 | No collapse of the test voltage occurs | Pass | |
| 7 | Partial Discharge Test | pC | The maximum level of partial discharges shall be 10 pC | ＜10 | Pass | |
04 Packing and Shipping
05 Site And Summary
In the critical field of power transmission and distribution, the opening winding dry type transformer has become an indispensable component of modern power systems due to its excellent performance and reliability. We are committed to providing our customers with high-quality dry type transformers, ensuring efficient energy utilization and safe operation. Whether in industrial, commercial, or residential applications, our dry type power transformer will provide you with stable and reliable power solutions. Choosing our products means choosing exceptional quality and superior service. Thank you for your trust and support; we look forward to working together to create a bright future.
