NEW YORK, July 31 (Reuters) - Exelon Corp’s (EXC.N) 1,152-megawatt Braidwood 2 nuclear power unit in Illinois was shut early Friday after the unit tripped off line late Thursday, according to separate reports from the U.S. Nuclear Regulatory Commission.
The unit, in Braceville, in Will County, about 60 miles southwest of Chicago, automatically tripped from full power late Thursday, the NRC said in an event report.
The NRC said an Unusual Event, the lowest of the agency’s four emergency classifications, was declared, due to the loss of offsite power for greater than 15 minutes.
“Unit 2 tripped as a result of the over-current trip of the 2 C reactor coolant pump. Both station auxiliary transformers on Unit 2 subsequently tripped off line. All control rods fully inserted on the trip. Auxiliary feedwater auto-started and maintained Steam Generator water level,” the report said.
The report added that the unit was stable and that Unit 1 was unaffected. Unit 1 continued to run at full power early Friday, according to the NRC’s reactor status report.
One MW powers about 800 homes in Illinois.
Exelon distributes electricity to 5.4 million customers in Illinois and Pennsylvania and distributes natural gas to 485,000 customers in the Philadelphia area. (Reporting by Eileen Moustakis; Editing by John Picinich)