ML19209C860

LER 79-035/03L-0:on 790922,plant Computer Failed.Caused by Printed Circuit Board Failure Which Generated Rapid Access Data Storage Disc Stop Signal.Circuit Board Replaced

ML19209C860
Person / Time
Site:	Calvert Cliffs
Issue date:	10/09/1979
From:	Davis S, Rizzo P BALTIMORE GAS & ELECTRIC CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19209C846	List: ML19209C845 ML19209C860
References
LER-79-035-03L-01, LER-79-35-3L-1, NUDOCS 7910180383
Download: ML19209C860 (1)

Text

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• LICENSEE EVENT REPORT CONTROL SLoCK: l 1

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lh (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION) o i l "l 0 LICENSEE l C l CCODE lNl2 l@l 0 l0 l- l 0 l0 0 l0 l0 l- 0l0l@l41111l1 25 26 LICENSE TYPE JO 1 l@l57 CAT l 58 l@

7 8 9 14 15 LICENSE NUMBER CON'T 7

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S$RCE60 ll l@ 610 l 5 1010 101311 1868 l@lo DOCKET NUMBER 69 19EVENT 12O ATE 12 17 lo 74 l@l1 75 lo in lo 17 lo80 @

RE8CRT DATE EVENT DESCRIPTION AND pro 8 ABLE CONSEQUENCES h a 2 At 1515 the olant operator noticed that the olant comouter had failed. I o 3 ;The computer was declared inoperable per T.S. 3.3.3.2. The excore [

o 4 l Nuclear instrumentation system remained ooerable durino the event. The I ois lcomouter was returned to service at 1950. This has not been a recetitive 1 0 l6 levent.

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LO 31 S i l/l 0 3I 29 LLJ 30 31 L2J 32 22 23 24 26 27 28 AK N A ON O PLANT VE HOURS S8 I FOR B. SUPPLIE YANLFACTURER La_]@lz_J@

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44 47 CAUSE DESCRIPTION AND CCRRECTIVE ACTIONS i o lCorouter failure was due to.a orinted circuit board (Zerox No. MT 56) 1 3

Ifailure which cenerated a RAD (Raoid Access Data) Storace disc "stoo" l 2 l signal. This board and one additional board (Zerox No. WT 57) which I i- l failed were reolaced. Both boards are cart of the RAD Motor Control I

,4 l Circuit. No oreventive action is reauired. I 7 8 3 80

$A S  % POWER OTHE R STATLS SO RY DISCOVERY OESCRIPTION l

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N/A l l A l@l Ooerator observation ACTIVITY C TENT

= ELE 4SEo or asLEASE AvouNT Cr 4CTiviTY @ LOCATION CF RELEASE 1 le IZ l @ l Zi@ l N/A 44

[3/A 45 80 l

6 3 10 11 8ERSONNEL EXPCSURES NUY9ER TYPE DESCRIPTICN 1

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NRC USE ONLY

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p'sSUCITYgi l;1"' ~ m oiso.3sa , ,, ,,,,,,,,,,3 7 3 10 68 69 80 3 NAME OF PAERARER S. M. Davis /P. G. Rizzo Puoys (in117'a 7047/7004: 2,