Things to consider when buying a transformer

Selecting and buying a transformer is not rocket science. However, keeping few points in mind will aid in selecting the right transformer with the right specifications.

• How many phases are required:The first consideration is to determine whether you need a single phase or three phase transformer. This is usually determined the by the equipment used more often. For small machines such as home appliances, single phases should do while for industries that operate large machinery, three phase is a must.
• What voltage:When deciding on a transformer, you must know the input and output voltage that is the primary and secondary voltage respectively. This can be determined by the power supply and voltage of the equipment you’re using.
• What frequency:The frequency of a transformer is usually determined by the power supply. Sometimes the incoming frequency varies from the output frequency required. This is normally done by using a frequency converter on the output of the transformer.
• Kva rating:Determine the load size and nature of the load. Transformer kVA sizing is calculated by the primary or secondary winding voltage and amperage information.
• Purpose of the transformer:Determine how the transformer is going to be used and for what purpose.
• Environment:It is critical to know where the transformer is going to be used, indoor or outdoor, in a hazardous area or an offshore location which all require different specifications. Most transformers that are used outdoor, are liquid-filled to protect the winding from the elements.
• Space requirement:Measure the area where the transformer will be installed.
• Wire configurations:Transformers can be connected in different configurations to meet almost any requirement. In the case of three-phase transformer windings, three forms of connection are possible; star, delta and interconnected-star.
• Miscellaneous:Apart from the above factors, consider the power factor, efficiency, impedance and cooling methods.

Keeping these points in mind will help you buy the right transformer for your industry.

Mr.Vathirajan, Managing Director of Padmavahini Transformers Pvt Ltd, Coimbatore. Manufacturers, Suppliers & Exporters of Electrical Power Transformers.