Buying a transformer is a long-term investment. For a power distribution project, factory, commercial building or renewable energy system, the transformer needs to work reliably for many years. That is why choosing a transformer only by price can create problems later. Before purchasing from a transformer manufacturer or supplier, it is useful to ask these 10 questions.
1. What transformer capacity do I need?
The required capacity depends on the actual electrical load, maximum demand and possible future expansion. A transformer should not operate continuously at its limit. Providing the supplier with your load information can help determine the appropriate kVA rating.
2. What are the input and output voltages?
The rated voltage must match the local power system. Common distribution transformer combinations include 11kV/0.4kV, 22kV/0.4kV and 33kV/0.4kV. Other voltage levels can also be designed according to the project requirements.
3. Should I choose an oil-immersed or dry-type transformer?
This depends mainly on the installation environment. Oil-immersed transformers are widely used in outdoor substations, utility networks and industrial applications. They offer efficient heat dissipation and are suitable for a wide range of capacities.
Dry-type transformers are often selected for indoor applications such as commercial buildings, factories, hospitals and data centers. They do not use insulating oil and can be a practical choice where fire safety and indoor installation are important.
4. What cooling method is required?
Cooling directly affects transformer operation and temperature rise. Oil-immersed transformers commonly use ONAN or ONAF cooling, while dry-type transformers can use natural air cooling or forced air cooling. Ambient temperature and load conditions should be considered during selection.
5. Which technical standard should the transformer meet?
Different countries and projects may require different standards. IEC, GB, ANSI and GOST are commonly encountered in international transformer projects. Buyers should confirm the required standard before ordering, especially when the equipment will be installed as part of a utility or EPC project.
6. What core and winding materials are used?
Material selection has a direct influence on transformer losses, temperature rise and service life. High-quality silicon steel is commonly used for transformer cores, while copper or aluminum can be selected for windings according to the project requirements. The material should be clearly specified in the technical documentation.
7. What tests will be performed before delivery?
Testing is an important part of transformer manufacturing. Depending on the project, routine tests may include winding resistance, voltage ratio, insulation performance, no-load loss, load loss and dielectric tests. Customers should ask for test reports before shipment.
8. Can the transformer be customized?
Not every project can use a standard configuration. Impedance, vector group, voltage ratio, cooling method, enclosure, accessories and protection devices may need to be adjusted. Working directly with an experienced transformer manufacturer can make customized requirements easier to handle.
9. How will the transformer be packed and shipped?
For export projects, transportation should be considered from the beginning. Large transformers need suitable lifting arrangements, strong export packaging and moisture protection. The supplier should also provide shipping dimensions, loading information and relevant documents for customs and installation.
10. Does the supplier provide technical support?
The relationship with a transformer supplier should not end after shipment. Drawings, test reports, installation manuals and technical assistance can be valuable during installation and commissioning. A supplier with its own engineering and production capabilities can usually provide faster technical communication when project requirements change.
Choosing the Right Transformer Manufacturer
At Tianjin Kechang International Trade Co., Ltd., we manufacture and supply oil-immersed transformers, dry-type transformers, switchgear, RMUs and compact substations for international projects.
Our approximately 15,000 m² manufacturing facility is equipped with automated production equipment, CNC busbar processing centers and testing systems. Our engineering team supports customized transformer designs for different voltage levels, capacities and operating environments. We follow applicable IEC, GB and other project standards and provide technical drawings, test reports and installation documentation with our equipment. When comparing transformer suppliers, look beyond the initial quotation. Transformer design, materials, testing, documentation, delivery and technical support all affect the real value of a transformer throughout its service life.
One-Stop Transformer & Power Solution Supplier in China
From design, manufacturing and testing to export packing and technical support, we deliver reliable power equipment for industrial, commercial and infrastructure projects.
