ENS Event | |
|---|---|
15:23 Mar 16, 2009 | |
| Title | Manual Trip Due to Failure of Technical Specification Required Fuel Thermocouple |
| Event Description | The licensee provided an informational call to inform the NRC Operations Center that it had manually tripped the research reactor from approximately 75% power (750 KW) due to the failure of a core fuel thermocouple that provides a reactor trip function. The technical specifications for the reactor require that two fuel centerline temperature thermocouples that provide a reactor trip function be available while the reactor is operating. The two fuel centerline thermocouples were confirmed to be functioning properly during a pre-startup surveillance earlier this morning. While at power the operators noticed fluctuations in one of the two thermocouple readouts. After about 4 minutes, it was concluded that one of the thermocouples was not functioning properly and the reactor was manually tripped to be in compliance with the technical specification action statement. The licensee was within technical specifications as soon as the reactor was tripped. The reactor did not trip automatically with the failure of the thermocouple because the failed thermocouple was providing a low temperature input into the reactor protection logic.
There were no other issues with the research reactor and the licensee noted that it was not required to make an immediate notification to the NRC Operations Center per its license. The licensee had also notified the NRC inspector for this facility (Pat Isaac) of this event. |
| Where | |
|---|---|
| Armed Forces Radiobiology Rsch Inst Bethesda, Maryland (NRC Region 1) | |
| License number: | R-84 |
| Reporting | |
| Information Only | |
| Time - Person (Reporting Time:+-1.48 h-0.0617 days <br />-0.00881 weeks <br />-0.00203 months <br />) | |
| Opened: | Steve Miller 13:54 Mar 16, 2009 |
| NRC Officer: | Bill Huffman |
| Last Updated: | Mar 16, 2009 |
| 44909 - NRC Website | |
Armed Forces Radiobiology Rsch Inst with Information Only | |
WEEKMONTHYEARENS 449092009-03-16T15:23:00016 March 2009 15:23:00
[Table view]Information Only Manual Trip Due to Failure of Technical Specification Required Fuel Thermocouple 2009-03-16T15:23:00 | |