Fuse failed and a reactor tripped

The Nuclear Regulatory Commission determined that the automatic shutdown last winter of an Oconee reactor was the mechanical failure of a fuse.  It was an Oconee Unit #2 reactor trip and the loss of four coolant pumps, according to NRC findings.  The government watchdog agency concluded no release occurred and the plant response was normal and the “unusual”event did not have an impact of public health and safety.  Further, it said, “The cause of the loss of power to all RCPs was the mechanical failure of an indicating fuse in the PT (potential transformer) circuit feeding the under voltage relay for the 6900V normal source power to the RCP.”  At the time, February 5, there were conflicting accounts of a fire.  But today an NRC spokesman, while acknowledging smoke resulted, there was no fire.  Since February 5, corrective actions have taken place, and Duke Energy’s Oconee vice president Steve Snider has told NRC there no more corrective actions needed.