ML20086F958
| ML20086F958 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 10/21/1975 |
| From: | Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML20086F955 | List: |
| References | |
| AO-75-66, NUDOCS 8401090724 | |
| Download: ML20086F958 (1) | |
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PHILADELPHI A* ELECT'RIC COMPANY /
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Peach', Bottom Atomic Power Station
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Delta, Pennsylvania i
17314 October 21, 1975 Mr. James P.
O'Reilly, Director Office of Inspectios and Enforcement-Region 1 United States nuclear Regulatory Commission hg d4uy2 631 Park Avenue King of Prussia, Pennsylvania 19k06
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Abnorcal Occurrence PL-Hour Notification, Confirming R. S.,F1eischsann's phone conversation with Mr. 'Jalt Saunack.
Re61on 1, United States Nuclear Regulatory Commission on October 21, 1975 Refe'rence:
License Number DPR Lk Technical Epecification
Reference:
Tables 3.1.1 and 3.2.0
' Report No.:
50-277-75-66 Report Date:
October 21, 1975 l occurrence Date:
October 20, 1975 Facility:
Peach Botton Atomic Power Station R.D.
1, Delta, Pennsylvania 1731h Identification of occurrence:
Y Upscale failure of the "B" logic APRM/RBM flow bias signal from yT-2-2-11CD.
Conditions Prior to occurrence:
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About 555 power.
Description of Occurrence:
i One of the two inputs to the "B" logic recire flow converter failed
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upscale.
This upscale failure raised the "B" logie ' APRM and RBM trip points'beyond those limits imposed by the Technical Specifications.
Designation of Apparent Cause of Occurrence:
Second ground on the.recire drive. flow transmitter' signal loop.
' Analysis of Occurrence:
s-This failure inhibited flow bias of the "3" APRM high flux scram, 3
however, scram would have occurred, although at a higher power level 4
I (not more than 120%) and therefore has minimal safety significance.
- Corrective Action:
A'"3" logic half sera = vas manually inserted until the flow signal could be repaired.
The flow signal was corrected by removing the installed 0
ground.
Loss.cf the remaining accidental ground vill not impare the flow signal to the neutron monitoring system.
Failure Data:
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'One previous reported as 50-277-75-30.
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[7ery truly yours,
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- '. T. Ullrich, Superintendent
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Peach Bottom Ato=ie Power Station l
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,(bic) 8401090724 7
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