The 1,000MW unit was expected to be restarted on the same day.
The Kozloduy nuclear plant has two 1,000MW reactors which provide 30% of the country’s power.
According to a statement quoted by AFP, "Unit 6 of the Kozloduy plant was shut down by the turbogenerator’s protection system," the plant said, adding: "No change in the level of radioactivity has been registered."
To fulfill one of the conditions to enter into the European Union, four older 440MW reactors at the plant were shut down in 2002 and 2006 respectively, reports AFP.
