500 kVA Three Phase Dry Type Transformer
Primary Voltage: 11KV
Secondary Voltage: 0.4KV
Power Rating: 500 KVA
Connection Type: Dyn11/Yyno or others
Transformer Type: Dry Type Transformer
Standards: ANSI/IEEE, CSA/CAN, DOE
Certificate: UL, cUL, CSA, SGS, CE
In power systems, transformers undertake the important responsibility of electrical energy conversion and distribution. As important energy nodes, they play an important role in stable and reliable electrical equipment. The 500 kVA Three Phase Dry Type Transformer, due to its structural characteristics and application advantages, shows excellent adaptability in industrial, commercial, and infrastructure fields in various regions.
Basic characteristics of dry-type transformers
A dry-type transformer refers to a transformer whose core and windings are not immersed in insulating oil. The epoxy resin cast three-phase dry-type transformer has stable operation, flame retardant and fireproof performance, no pollution, and can be directly installed at the load center. It is maintenance-free and easy to install. It has good moisture resistance and can be put into operation without pre-drying after shutdown. It has low loss, low partial discharge, low noise, and can operate at 120% rated load under forced air cooling conditions. It is equipped with a complete temperature protection control system, providing reliable protection for the stable operation of the transformer.
About the comparison between oil-immersed transformers and dry-type transformers
| Item | Oil-Immersed Transformer | Dry-Type Transformer |
| Insulation Medium | Transformer oil | Air / Epoxy resin |
| Cooling Method | ONAN / ONAF / ODAF | AN / AF |
| Fire Protection Rating | Flammable, fire protection measures required | Flame retardant Class F / H, can be installed adjacent to buildings |
| Overload Capacity | Strong | Relatively weak |
| Noise Level | Low | Relatively high |
| Maintenance Workload | High (oil testing, leak handling) | Low |
| Environmental Impact | Risk of oil leakage and pollution | Oil-free, no pollution |
| Cost | Low | High |
| Applicable Voltage Level | 10kV ~ 1000kV+ | Mainly 10kV / 20kV, limited 35kV |
| Service Life | Long | Medium |
Not sure which type of transformer is more suitable for your project? We also provide high-quality 500 kVA oil-immersed transformers.
Main technical parameters of the product
SCB-500kVA-10/0.4 dry-type transformer is one of the most typical transformer parameters. “500kVA” indicates that the rated capacity is 500 kilovolt-amperes. In the parameter “10kV/0.4kV”, the rated voltage on the high-voltage side is 10 kilovolts, and the output voltage on the low-voltage side is 0.4 kilovolts, which can adapt to the voltage standards of most distribution scenarios.
The insulation class is usually Class F or Class H, corresponding to maximum temperatures of 155°C and 180°C, ensuring the thermal stability of the transformer during long-term operation. Taking Class H as an example: 180°C is the limit temperature of the winding. If the limit temperature is exceeded, the winding insulation material will fail. The winding must never be allowed to operate at such a high temperature of 180°C, as it will greatly shorten the service life of the transformer. It should operate long-term at the performance reference temperature of 145°C or below.
Regarding the protection level, the dry-type transformer body does not have high protection capability. Generally, after an enclosure is selected, the protection level of the whole unit can reach IP20. Some enclosures can reach IP23, which can prevent foreign objects from entering and provide a certain drip-proof function.
In terms of energy efficiency, this type of transformer can be customized according to various standards (ANSI/IEEE, CSA/CAN) based on customer requirements. Based on the professional capability of our company (CHBEB), we ensure that the customer’s project can be implemented more smoothly.
Structural and process features
The core components of a dry-type transformer include the core, high-voltage winding, low-voltage winding, and cooling air ducts.
Core
The core is made of high-quality cold-rolled silicon steel sheets, with a 45-degree step-lap full miter joint structure. The three-shear two-punch core corner-cutting cross-shearing process and five-step step-lap cutting and core stacking process improve the magnetic flux distribution at the joints and reduce the vibration energy of the core. The core adopts integrated curing and surface sealing with insulating resin, effectively reducing no-load loss, no-load current, and core noise.
High-Voltage Coil
The high-voltage coil is wound with high-quality insulating materials. For larger-capacity coils, heat dissipation air ducts are arranged along the axial direction. This structure has good resistance to current impact, temperature changes, cracking, and excellent heat dissipation performance. It adopts a multi-stage segmented cylindrical structure, with strong overvoltage withstand capability and very low partial discharge level. The coil is molded and cast after vacuum drying.
Casting & Curing Process
The entire casting and curing process is completed according to a pre-programmed process curve. Precise process control ensures that the coil has no pores or cavities.
Low-Voltage Coil
The low-voltage coil adopts a foil structure, effectively solving the ampere-turn imbalance problem of low-voltage, high-current coils when using wire-wound structures. At the same time, the foil coil has no axial turns or axial winding spiral angle, effectively eliminating the axial force of the transformer during short circuit, ensuring that the current density inside the coil can be freely adjusted along the axial direction according to the load distribution of the high-voltage coil, and reducing the radial force during low-voltage sudden short circuit. After winding, the coil ends are sealed and cured with resin to prevent the entry of various foreign objects and moisture.
Application scenarios
Because the 500 kVA Three Phase Dry Type Transformer has the advantage of no insulating oil, the installation site does not need to consider oil pits or oil drainage facilities, reducing civil engineering requirements and fire protection pressure. It is especially suitable for indoor places with limited space or high safety standards. Therefore, it is widely used in the following scenarios:
Industrial Plants
Providing power for production equipment, lighting systems, and auxiliary facilities.
Commercial Buildings
Distribution rooms in shopping malls, hotels, or office buildings.
Public Facilities
Transformer systems in schools, hospitals, and other public service places.
Selection and installation precautions
Selection
When selecting a 500 kVA dry-type transformer, it is necessary to clarify the voltage requirements, load characteristics, and installation environment. Key parameters include capacity, rated voltage, impedance voltage, connection group, etc., combined with existing grid conditions. Finally, attention should be paid to the energy efficiency level of the transformer, and products with lower losses should be selected to reduce long-term operating costs.
Installation
During installation, it is necessary to ensure that the transformer room has good ventilation conditions and avoid direct sunlight and humid environments. The foundation base must be level and firm, and enough space should be reserved for future maintenance. During wiring, strictly connect the high-voltage and low-voltage cables according to the markings, and ensure proper grounding protection.
Daily operation inspection
During daily operation, the following abnormal phenomena should be checked:
- Overheating phenomena (local discoloration, odor)
- Discharge traces (carbonized points, creepage paths)
- Abnormal sounds (discharge sound, vibration sound)
- Cracks on the coil surface or resin aging
Supply and supporting services
CHBEB, as a professional transformer manufacturer, can provide standard models or customized special specifications according to project requirements. In some regions, on-site survey, installation guidance, and commissioning services can be provided to ensure stable operation after the equipment is put into service.
During the procurement process, users should pay attention to the product certificate of conformity, type test report, and after-sales guarantee content. Delivery cycle and transportation method should also be confirmed in advance to avoid affecting project progress.
The 500 kVA dry-type transformer, in its supply and use in various countries and regions, meets the actual needs of local power construction and development. Its characteristics of safety, reliability, and simple maintenance make it a suitable choice for many distribution applications. During selection, installation, and use, users can fully exert its performance based on their own conditions and technical requirements, providing support for the stable operation of the power system.
