ML20248E548
| ML20248E548 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 09/29/1989 |
| From: | Mazumdar S NRC OFFICE FOR ANALYSIS & EVALUATION OF OPERATIONAL DATA (AEOD) |
| To: | Rosenthal J NRC OFFICE FOR ANALYSIS & EVALUATION OF OPERATIONAL DATA (AEOD) |
| Shared Package | |
| ML20248E552 | List: |
| References | |
| AEOD-T919, NUDOCS 8910050281 | |
| Download: ML20248E548 (1) | |
Text
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SEP 2 91999 MEMORANDUM FOR: Jack E. Rosenthal, Chief (Distribution Reactor Operations Analysis Branch PDRt Division of Safety Programs, AE00 Central File ROAB R/F THRU:
Matthew Chiramal, Chief DSP R/F Engineering Section SMazumdar Reactor Operations Analysis Branch MChiramal Division of Safety Programs, AEOD JRosenthal KBlack FROM:
Subinoy Mazundar, Electrical Engireer MWilliams Engineering Section VBenaroya Reactor Operations Analysis Branch TNovak Division of Safety Programs, AEOD CHeltemes BBrady
SUBJECT:
FAILURE OF OVER CURRENT PROTECTIVE DEVICE WLanning AT PALISADES UNIT 1 MTaylor LSpessard HFaulkner Enclosed is our Technical Review Report on fcilure of overcurrent (0C) protec-tive relays at Palisades 1.
Since February 5,1987, five service water pump trips have occurred at Palisades due to OC relay settings being marginally low.
An SCSS search indicates six similar failures from 1980 through mid-May 1989.
Five of these failures are due to improper settings of the OC devices and only one due to a drift of the OC trip setting.
Our NPRDS search indicates 61 records on failure of Westinghouse OC devices, 32 records on failure of G.E. OC devices and 11 records on failure of ITE OC devices.
Considering the large number of OC devices used in each nuclear plant, this failure rate is not alarming and is likely to go down further as the licensees gain more experience and improve their maintenance procedures with time.
However, considering the important part played by protective equipment, it is desirable that in the future all Class 1E OC devices failures be investigated in-depth to establish the root cause of each failure.
Subinoy Mazumdar, Electrical Engineer Engineering Section Reactor Operations Analysis Branch 89100502s1 890929 Division of Safety Programs ADOCK 0500 5
pR Office for Analysis and Evaluation of Operational Data
Enclosure:
As stated cc:
F. Rosa, NRR
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