The country previously halted the operations of some of its 23 reactors last November after a scandal emerged over parts being supplied using fake documents.
Asia`s fourth-largest economy is heavily dependent on oil, gas and coalimports, but usually gets about a third of its electricity from nuclear powergeneration.
The nuclear problems could increase the risk of power shortages in the hot Korean summer when power demand is seasonally high for air conditioning.
The shutdown would take place on Tuesday, according to a spokesman at Korea Hydro and Nuclear Power Co Ltd, which runs nuclear reactors inSouth Korea and is owned by state-run utility Korea Electric Power Corp.
Of the three reactors, two are in Kori, about 320 km southeast of the capital Seoul, and one is in Wolsong, about 280 km from Seoul, a statement from the Nuclear Safety and Security Commission said. The reactors each have a capacity of 1,000 megawatts.
A fourth newly built nuclear power reactor, also in Wolsong, which is waiting for operational approval, would also have its cable replaced, the statement added.
The energy ministry would hold a news briefing later Tuesday on the issue, according to ministry officials.
Last year, South Korea was forced to take power saving measures in a bid to avoid blackouts after it closed two reactors to replace parts supplied with fake certificates and extended the shutdown of another reactor where microscopic cracks were found.
South Korea halts more nuclear reactors over fake certificates
28 May 2013
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South Korea is suspending the operations of two nuclear power reactors and extending a shutdown of a third for maintenance to replace cables that were supplied using fake certificates, the country`s nuclear regulator said on Tuesday.
