An Unusual Event was declared at PSE&G-owned Salem nuclear plant in New Jersey after the Unit 1 reactor tripped and experienced a safety injection (SI) signal due to a high steam flow coincident with a low steam pressure signal, according to a Monday report.
According to the NRC, "At the time of the safety injection signal, function testing of the 1PT505 turbine inlet pressure channel was in progress. This testing required the tripping of the high steam flow bistables. As a result of the reactor trip and safety injection signal, the Emergency Diesel Generators started but did not load, the ECCS system (high head safety injection pumps actuated and injected into the reactor vessel, intermediate head safety injection pumps and low head (RHR) safety injection pumps) actuated. All 4 main steam isolation valves closed along with feedwater isolation and start of the auxiliary feedwater pumps. All control rods fully inserted following the reactor trip. Following the main steam line isolation, the atmospheric relief valves opened along with the lifting of several main steam safety valves."
The Unusual Event, which was declared due to multiple fire alarms involving the containment building, was terminated after operators determined that there was no fire.
Salem's Unit 2 was not affected and continues to operate at full power.