Voltage Ratio = Primary Turns / Secondary Turns
Por ejemplo:
Transformador reductor
Input:
13.8kV
Output:
480V
The transformer reduces medium voltage electricity to a usable low voltage level for industrial equipment.
Three Phase Transformer Types
Three phase transformers can be classified according to construction, insulation method, cooling system, and application.
1. Three Phase Dry Type Transformer
A three phase dry type transformer uses air as the cooling and insulation medium instead of transformer oil.
Dry type transformers are widely used where fire safety and environmental protection are important.
Advantages of Dry Type Transformer
Alto nivel de seguridad contra incendios
Sin riesgo de fugas de aceite
Requisitos de mantenimiento mínimos
Apto para su instalación en interiores
Respetuoso con el medio ambiente
Common Applications
Three phase dry type transformers are commonly installed in:
Edificios comerciales
Hospitales
Aeropuertos
Centros de datos
Instalaciones industriales
Centros comerciales
Typical ratings:
| Capacidad | Aplicación |
|---|---|
| 15 kVA | Small commercial loads |
| 45 kVA | Industrial equipment |
| 75 kVA | Building power supply |
| 500 kVA | Factory distribution |
| 2500 kVA | Large industrial systems |
EverNew manufactures dry type transformers with:
- Copper winding
- Aluminum winding
- Cast resin insulation
- UL/CSA compliant designs

2. Three Phase Oil Immersed Transformer
A three phase oil immersed transformer uses insulating oil for cooling and electrical insulation.
Oil immersed transformers are commonly used for outdoor power distribution because they provide excellent heat dissipation and high capacity capability.
Ventajas
- High power capacity
- Excelente rendimiento de refrigeración
- Larga vida útil
- Suitable for outdoor applications
Aplicaciones
Common applications include:
- Subestaciones eléctricas
- Parques solares
- Parques eólicos
- Plantas industriales
- Power transmission systems
Typical voltage ratings:
- 6kV
- 10kV
- 11kV
- 13.8kV
- 35kV
- 110kV
- 220 kV
3. Three Phase Distribution Transformer
A three phase distribution transformer is designed to reduce medium voltage electricity to low voltage for end users.
Typical conversion:
11kV → 400V
13.8kV → 480V
35kV → 400V
Aplicaciones:
- Zonas residenciales
- Commercial facilities
- Fábricas industriales
4. Three Phase Power Transformer
A transformador trifásico de potencia is used in high voltage transmission and substations.
Aplicaciones:
- Centrales eléctricas
- Grid substations
- Proyectos de energías renovables
Rango de potencia:
From several MVA to hundreds of MVA.

Three Phase Transformer Applications
Sistemas de energía industrial
Factories rely on three phase transformers to supply power for:
- Motores
- Compressors
- Pumps
- Máquinas CNC
- Líneas de producción
- Automation equipment
Industrial transformers usually require:
- Alta eficiencia
- Funcionamiento continuo
- Strong overload capability
Edificios comerciales
Three phase transformers are commonly used in:
- Edificios de oficinas
- Hoteles
- Centros comerciales
- Aeropuertos
A common North American system:
480V → 208Y/120V
This voltage system is widely used for:
- Lighting
- Sistemas de climatización
- Building equipment
Proyectos de energías renovables
Solar and wind projects require transformers to increase voltage before grid connection.
Ejemplo:
Solar inverter:
800V
↓
Transformer:
0.8kV / 35kV
↓
Grid connection
Three Phase Transformer Voltage Ratings
Different countries use different voltage standards.
Norteamérica
Common voltages:
| Tensión primaria | Tensión secundaria |
|---|---|
| 480V | 208Y/120V |
| 600V | 347/600V |
| 13.8kV | 480V |
| 34,5kV | 480V |
International Markets
Common systems:
| Primary | Secondary |
|---|---|
| 10kV | 400V |
| 11kV | 415V |
| 20kV | 400V |
| 35kV | 400V |
EverNew transformers can be designed according to:
- IEC
- ANSI
- IEEE
- UL
- CSA
- CE
- GOST

How To Select A Three Phase Transformer?
Para elegir el transformador adecuado, es necesario evaluar varios parámetros técnicos.
1. Transformer Capacity (kVA)
The transformer capacity must match the electrical load.
Common sizes:
- 15 kVA
- 30 kVA
- 45 kVA
- 75 kVA
- 112,5 kVA
- 150 kVA
- 500 kVA
- 1000 kVA
- 2500 kVA
2. Tensión de entrada y de salida
Ejemplo:
Commercial building:
Input:
480V Three Phase
Output:
208Y/120V Three Phase
3. Frequency
Common frequencies:
- 50Hz
- 60Hz
4. Transformer Cooling Method
Choose according to installation environment:
Indoor:
Transformador seco
Outdoor:
Transformador sumergido en aceite
5. Transformer Standards
Los proyectos internacionales pueden requerir:
- UL certification
- CSA certification
- DOE efficiency
- Normas de la IEC
- Normas del IEEE

Three Phase Transformer Manufacturer
Selecting a reliable three phase transformer manufacturer is important for ensuring safety, efficiency, and long service life.
A professional transformer supplier should provide:
✔ Engineering design support
✔ Factory testing
✔ International certifications
✔ Customized voltage solutions
✔ Export experience
Why Choose EverNew Transformer?
EverNew Transformer is a professional transformer manufacturer in China with more than 30 years of experience.
Our manufacturing capabilities include:
Product Range
- Transformador de distribución
- Transformador seco
- Transformador sumergido en aceite
- Transformador de pedestal
- Transformador de potencia
Technical Capability
Capacidad:
15 kVA – 500 MVA
Tensión:
6kV – 500kV
Certificaciones
- UL
- CSA
- CE
- GOST
- ISO
We supply transformers for:
- EE.UU.
- Canadá
- América del Sur
- Europa
- Asia
- África
Three Phase Transformer FAQ
What is the difference between single phase and three phase transformer?
A single phase transformer is normally used for smaller loads, while a three phase transformer is designed for industrial and commercial power systems requiring higher capacity.
What is the most common three phase transformer voltage?
Common systems include:
- 480V
- 208Y/120V
- 400V
- 415V
- 13.8kV
- 35kV
How much does a three phase transformer cost?
El precio depende de:
- Transformer capacity
- Voltage rating
- Bobinado de cobre o aluminio
- Método de refrigeración
- Normas obligatorias
- Order quantity
How do I choose a three phase transformer size?
You should consider:
- Total connected load
- Starting current
- Future expansion
- Requisitos de tensión
- Efficiency requirements
Conclusión
A three phase transformer is an essential component in modern electrical power systems, providing efficient voltage conversion for industrial, commercial, and renewable energy applications.
Choosing the correct transformer requires careful evaluation of:
- Power capacity
- Voltage levels
- Método de refrigeración
- Entorno de instalación
- International standards
Como profesional three phase transformer manufacturer, EverNew Transformer provides reliable transformer solutions worldwide with customized designs from low voltage distribution systems to high voltage power networks.
Contact EverNew Transformer today for your three phase transformer project.


