Eskom said that Koeberg Unit 2 inadvertently tripped during work on Unit 1, which is currently offline. The second unit was switched off in accordance with protocol, Eskom said, adding that start-up process for the tripped unit was in the works.
Unit 2 is expected to be reconnected to the national grid within 48 hours, state power utility Eskom said.
Koeberg power station, north of Cape Town, is currently the only commercial nuclear power plant in Africa and its two units contribute around 1,860 megawatts or 5% of national power supply.