Transformers are used in most electrical equipment and devices as a way to convert or transform power from one voltage system to another. This is done through the use of electromagnetic fields in a relatively simple design and application.
The Basics
By definition, an electrical transformer is a static component. This means that they do not contain any moving parts. Instead, a transform consists of a core, which is typically a magnetic core, with windings of wire, typically copper, that include a primary and secondary winding.
The AC current comes in on the primary winding, where it creates an electromagnetic field. The secondary windings receive this energy, in the form of voltage, either at the same power or with a step-up or step-down.
Selection Criteria
To get the correct electrical transformer, it will be important to consider the following issues:
- Size – the physical size of the transformer, as well as the power rating required, will be essential based on the specific applications. It is not uncommon to require a custom design in an electrical transformer to meet the requirements of prototypes or specific types of electrical systems. Weight may also be a factor to consider based on the installation location.
- Location – where the transformer will be used will also need to be carefully considered. This is particularly true when the transformer is going to be outside where humidity, pollutants it the air and other types of potential corrosive agents may be present.
- Cooling requirements – large transformers are typically cooled either with oil or with air or gas. There are specific restrictions for these types of transformers, particularly oil cooled, as it relates to both industrial use or use in specific types of applications.
- Special requirements – for large or small transformers, it is important to consider any special shape or material considerations. Selecting between single and three phase transformers will be required, and this is dictated by the application.
