Caption: Entergy's Indian Point Nuclear Power Plant
The Indian Point 3 nuclear power plant in New York automatically shut down June 15 after a turbine trip then tripped the reactor offline.
Plant operator Entergy (NYSE: ETR) said that the plant experienced an electrical disturbance external to the plant, which caused a generator to shut down as designed. All backup power systems operated as designed and all control rods were fully inserted. Unit 2 continued to operate.
A report filed with the U.S. Nuclear Regulatory Commission (NRC) said a preliminary investigation shows that Breaker Number 1 in the ring bus was intentionally opened by plant personnel due to a problem on an output feeder from the ring bus. Subsequently, breaker #3 opened and caused the turbine and reactor trip of the unit.
Unit 3 returned to service May 24 after a main electrical transformer failed and caught fire on May 9.
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