The beleaguered company, which runs 15 aging coal-fired power stations, resumed more than two hours of a rolling power cut on Saturday between 5 p.m. (1500 GMT) and 10 p.m., after suspending it on Friday. nL3N2X6081
"On Monday and Tuesday evening, at the same times, load shedding will be implemented at Stage 3," Eskom said in a statement.
"Thereafter load shedding will be reduced to Stage 2 for the rest of the week."
Stage 3 is a level of a power cut on an eight-level system under which the utility implements a seven and a half hour rolling outage across the country. Stage 2 is a five-hour rolling blackout.
One unit at three different power stations broke down on Saturday evening, Eskom said, making a third of its capacity non-operational due to unplanned outages.
It has a nominal power generation capacity of just over 45,000 MW, according to its website.
Eskom warned on Wednesday that the country "desperately" needed between 4000 and 6000 MW of additional capacity and unless that demand is met, rolling blackouts will be a regular occurrence in Africa's most industrialized country.
This year, up to May 10, the utility has implemented 31 days of a power cut, or load shedding as it is called locally, compared with 26 days in the same period last year.