Size/Capacity/kVA Rating

kVA rating of transformer(s) is decided on the basis of the subsequent factors:

• existing load to be catered;
• future load growth to be absorbed;
• diversity factor (DF) of load for different categories of consumers.

Diversity factor is greater than or equal to one and could be used to get the required rating through dividing the sum of maximum demand of individual consumer categories through DF;

• margin for future load growth;
• safety factor for avoiding overloading;
• level of all day efficiency to be achieved; and
• selection of an optimum loading of transformer(s), commonly around 60%, used to compute the required capacity of the transformer(s).