Buying Electrical Transformers The Right Way


Electrical transformers are integral for proper functioning of any electrical device, if the supply voltage is not the same as the operating voltage. However, you can’t just use any transformer available. There are a wide range of transformers, each having its own construction and purpose, from which you need to choose the most appropriate transformer for your application. Not every transformer can be used for every application. Some of the most common transformers include power transformers, step-up and step-down transformers, isolation transformers, auto transformers, toroidal transformers, UI transformers, EI transformers, and SMPS transformers. But, which transformer should you choose for your application? Below are some aspects you need to consider before buying a transformer so that you are able to find the right one.

Winding material

While the most basic material used for transformer winding is copper, the next best alternative is aluminum. Copper has better conductivity, but is also comparatively heavier. Thus, for an efficient transformer requirement, copper windings are better; while for a light weight transformer, aluminum windings are a better choice.

Type of core

You need to identify whether you need a closed core transformer or a shell-type transformer. Closed core transformers, where the windings surround the core, provide better insulation, but uses more copper and suffers more losses. Shell type transformers are just the reverse.


Some transformers operate on a single phase, while others operate on three phases. Thus, if the power to your transformer is being supplied from a three phase source, it is better to get a three-phase transformer instead of three individual single-phase transformers.

Step-up or step-down

Evaluate the voltage requirements of the device that needs to be connected to the transformer, and the supply voltage being provided to it. You’ll need a step-up transformer when the output voltage is higher than the input voltage, and a step-down transformer when the input voltage is higher than the output voltage.

Input and output voltages

The input voltage that is supplied from the power line, and the output voltage that is supplied to the electrical device connected to the transformer, must match the supply voltage and input voltage requirement of the device.

Power rating

You must check for the maximum power that a transformer can handle without causing any damage to the transformer and its winding, which is expressed in kVA or kW.

AC frequency

The AC supply works at a particular frequency, and if this frequency of the transformer is not the same as that of the supply, the functioning of the transformer is affected. You must thus make sure that the transformer you buy operates at the same frequency.

Coolant type

Transformers get heated up as they operate, which requires a good cooling system. There are three types of coolants – air cooled, liquid cooled, and liquid cooled with low vapourization point. Evaluate each of these and determine the type of coolant that you’ll require for your transformer.


Last but not the least is the manufacturer you are approaching. Once you have decided upon all the aspects of your transformer, you also need to ensure that you are having your transformer manufactured from a reputed and reliable manufacturer. No matter what your requirement and what your choice at present, you must always choose a manufacturer with versatile options. For example, you may now need one type of transformer, but in the future, you may require another. Also, you may now be okay with buying a readily available transformer, but may need a specific customized one in the future. Where would you then run around to find another manufacturer for your requirements? It is thus advisable to find a manufacturer who can solve all kinds of purposes, whenever needed. Miracle Electronics is one such name you can rely upon for all your needs, which is why it is named as the most reliable and reputed power, toroidal, isolation, auto, SMPS, UI, and EI transformer manufacturer in India.

Comments are disabled.