Distribution Transformer Losses

a)  No-load losses, i.e., iron losses:

No-load losses in kWh

of one distribution transformer =  No load loss of transformer in kW x number of hours the transformer was in service during the month

b)  Load losses, i.e., copper losses:

Copper losses in kWh = Copper loss of each transformer capacity wise in kW x (Actual load / Full load)²  x number of hours the transformer capacity wise was in service during the month x LLF