100 MVA power transformer was damaged when over-heating of the equipment led to a fire at the 220 KV sub-station in Okhla.
Power supply to parts of South Delhi was affected after the fire in the sub-station near Crowne Plaza Hotel. No one was injured in the blaze.
18 fire tenders were rushed to douse the flames. Eight fire stations were pressed into action, a Fire official said. The trigger is being investigated.
As a precautionary measure,the sub-station was isolated from the grid,a DTL official said. Power supply was normalised by 4 pm, the official said.