Engineering News 6 September 2011.

South Africa’s state-owned power company Eskom said one of the two units at its Koeberg power plant shut down automatically on Monday but there was no interruption to power supply.

“The automatic shutdown was triggered by the protection system on a motor due either to mechanical or instrumentation failure. Eskom is investigating the cause of the fault,” Eskom said in a statement.
Edited by: Reuters

Source: http://www.engineeringnews.co.za/article/eskom-says-one-of-koeberg-units-down-2011-09-06