The electricity supply was disrupted at around 7 pm plunging the major part of the steel city into darkness.
Meanwhile, Tata Power in a press statement stated "At about 1900 hours Jojobera units (1,4,5 &6) running at full load tripped due severe fault at DVC end. Only unit no 3 survived and is on line.
"We are in the process of taking other units in service one by one," the statement said.