ML20086J187
| ML20086J187 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 11/26/1974 |
| From: | Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| Shared Package | |
| ML20086J183 | List: |
| References | |
| AO-74-30, NUDOCS 8401230284 | |
| Download: ML20086J187 (1) | |
Text
.>' -
PHILADELPHIA ELECTRIC COMPANY DELW G D
[0 I
L..
Pg Battom Atonic Power StatfC MR LA.)BL t B Al2 N AW Delto. Psnnsylvania j
j 17314 I**D'Y 20e 1974
- Mr. James P, O'Reilly, Director iUnited States Atomic Energy Commission iDirsetorate of Regulatory Operations
,631 Park Avenue iKing of Prussia Pennsylvania 19406
Subject:
g normal occurrence 24-ilour Notific_atio_n
- Ccnfirming W. T. U11 rich's phone conversation with Mr. Walt Baunack, A.E.C. Region 1 1R2gulatory Operations Office on November 26, 1914 iR3ference
License Number DPR-56 Technical Specification Ref erence Table: i 3.2.B
!Rsport No.:
50-278-74-30 4R3 port Date:
November 26, 1974
! Occurrence Date:
November 25, 1974
- Pccility
Peach Bottom Atomic Power Station R.D. 1, Delta, Pennsylvania 17314
! Identification of Occurrence:
Failure of relay 14A-K9B in the LPC1/ Core Spray low reactor pressure permissive logic t3 make-up consistently.
- Conditions Prior to Occurrence
Unit 3 operating at.63% power, iDoccription of Occurrence:
During a routine instrument surveillance test on PS-3-3-52B, its relay (14A-K9B) to th2 LPC1/ Core Spray low reactor pressure permissive logic failed to makeup consistentlyj
- Decianscion of Apparent Cause of Occurrence:
Dirty and slightly misaligned relay contacts.
.Analyais of Occurrence:
Beccuse this switch / relay combination operates in a one-out-of-two-twice logic, the icilure of any one of the four devices will not render the logic inoperable.
There-fare, the safety implications of this single failure are minful.
Carrective Action:
Inysstigation revealed that a slight contact misalignment coupled with dirty contacts led to the inconsistent relay contact make-up.
The contacts were burnished and realigned and the relay operation again checked repeatedly with no further failures.
JPailure Data:
Previous relay contaee problegs reported as. 50-277-74-5, 50-277-74-9, 50-277-74-50.
WO3 WRG 3,i]Gw m a p, p s.,...fy,f.
l,
-Vary truly yours, j'. y *fffd' O I I Yid E Ogg yzgg W. T. Ullrich, Superintendent Deach Botton Atomic Power Statio63413339 g4 Ig00 05 S
- i..; '
',j.
-