Vogtle unit 2 was shut down for the second time in four days Tuesday because of a diminished condenser vacuum.
The Westinghouse reactor operated by Southern Co. had shut down automatically from full power Saturday morning following a turbine trip, according to a report filed with the Nuclear Regulatory Commission. The shutdown proceeded without incident, and Southern dispatched a forced-outage response team to investigate the event and plan a restart. A statement the company issued to Georgia media indicated the shutdown followed a loss of excitation from the main generator.
The unit was at 27 percent power just before noon Tuesday when operators tripped the reactor manually. According to the NRC, a main feedwater pump was out of service for scheduled maintenance at the time. Its casing was being removed when the condenser vacuum started to lower because of an isolation valve not holding pressure. Once the vacuum reached a certain threshold, plant procedures required the unit be shut down. The trip was uneventful, and unit 1 continued to operate normally at the site near Augusta, Ga.