Unit 3 at Connecticut's Millstone nuclear plant shut down unexpectedly Friday after the water level dropped in a steam generator.
According to a report filed with the Nuclear Regulatory Commission, the loss of an electrical bus caused a feed water transient. Safety systems shut down the reactor automatically from full power when steam generator water levels dropped below a certain point. The plant did not declare an emergency, and the shutdown was uncomplicated. No relief valves opened, and the event did not affect unit 2.
Dominion operates the plant near New London, Conn. Unit 3 is a 1,150 megawatt Westinghouse pressurized water reactor first licensed in 1986.