ML20149K331
| ML20149K331 | |
| Person / Time | |
|---|---|
| Site: | Farley  |
| Issue date: | 05/28/2020 |
| From: | Christopher Hunter NRC/RES/DRA/PRB |
| To: | |
| Littlejohn J (301) 415-0428 | |
| References | |
| LER 1982-022-00 | |
| Download: ML20149K331 (1) | |
Text
LER 364/82-022 Event
Description:
Transient with One HPI Pump Inoperable Date of Event:
May 19, 1982 Plant:
Farley 2 Summary On May 19, 1982 during the monthly operability check of Charging Pump 2A, the pump was declared inoperable when it would not start. The charging pumps feeder breaker DF06 failed to close due to a misaligned microswitch arm. The arm was repaired and the charging pump was declared operable approximately 1.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> later. A plant trip occurred one week before the discovery of the faulted charging pump. Three charging pumps are used for high-pressure injection and feed and bleed.
This event was modeled as a transient with one charging pump (one train of high-pressure injection (HPI) and FEED.AND.BLEED) inoperable. The estimated conditional core damage probability is 1.6x10-6. The dominant sequence involved the failure of auxiliary feed water, the failure of main feed water, and the failure of feed and bleed.