A technical glitch automatically shut one unit at Bulgaria's Kozloduy nuclear plant but did not pose a risk of nuclear contamination, the plant said on Saturday.
Kozloduy said the temporary closure of the 1,000-megawatt unit 6 was caused by a malfunction of a turbogenerator protection system at 4:19 a.m. (0119 GMT)
"We're working to resolve the technological problem and the plan is to reconnect the reactor later on Saturday," said a statement issued by officials at the plant, adding the other 1,000 megawatt reactor - unit 5 - is working at maximum capacity.
Kozloduy's two 1,000 megawatt Soviet-made nuclear reactors produce about 36 percent of the electricity in the Balkan country.
Bulgaria has closed four older reactors at its sole nuclear plant in the past several years under a treaty with the European Union and over safety concerns raised by Brussels.
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