Four memory chip lines 7, 8, 9, 14 and two non-memory chip lines 6 and S, were halted for as long as 22 hours between Friday and Saturday as electricity went out at the factory complex in Giheung, Gyeonggi Province, due to an overheated transformer unit.

Samsung had reacted swiftly to fix the power unit and restarted all the lines by Saturday noon. But it has to wait for weeks to check whether production has reached normal levels since semiconductor wafers stay on a line for about 40 days while being processed, it said.

The firm also said that it would be able to catch up with its original production schedule this month itself by increasing production and tightening its quality inspection procedure.
The firm also opened its high security facilities, usually closed to outsiders, to reporters on Monday.

When news of the power failure first broke on Friday, several stock analysts had predicted that lines would remain ineffective for weeks and the accident would cost Samsung as much as 700 billion won, a figure contested by company executives, who put the losses at no higher than 40 billion won.

Samsung is covered by a one-year insurance policy with compensation of up to 5.5 trillion won ($6 billion) sold by Samsung Fire & Marine Insurance, for which it paid 85 billion won. But it hasn''t decided whether to request the compensation because it will increase insurance premiums when the contract is renewed next year.