ML19211A271

LER 79-111/03L-0:on 791114,during Surveillance Testing, Accelerometer Tracer Could Not Be Discerned Due to Excessive Noise.Caused by Component Failure.Source of Noise Being Investigated,Possibly Caused by Battery Charger

ML19211A271
Person / Time
Site:	Davis Besse
Issue date:	12/11/1979
From:	Aebie K TOLEDO EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19211A270	List: ML19211A269 ML19211A271
References
LER-79-111-03L, LER-79-111-3L, NUDOCS 7912170297
Download: ML19211A271 (2)

Text

U.S. NUCLEAR REGULATORY COMMISSION NRC FOR@3GG vm LICENSEE EVENT REPORT CONTROL BLOCK: l i

l l l l l e

lh (PLE ASE PRINT OR TYPE ALL REQUIRED INFORMATION) o 1 l0lHlDlBlS 1 l@l 0l 0l -l 0 l 0 l N l P l F l- l $25 l 3 2b l@l4 LICENSE l1 l1 TYPE l1 JO l 1 l

l@l bi LA T bd l@

7 8 9 LICENSEE CODE 14 15 LICENSE NUMtiEH CON'T s[gC " l L }@l 0 l 5 l 0 l- l 0 l 3 l 4 68l 6 69@l 1EVENT l 1 DATE 11 l4 l 7 l 9 j@l1 l 2 1l1l7l980 @

_o 7 i

8 60 Gl DOCKET NUMB ER F4 lb REPORT 0 ATE EVENT DESCRIPTION AND PROBABLE CONSEQUENCES h

_ o 2 l0n 11/14/79 at 1200 hours0.0139 days <br />0.333 hours <br />0.00198 weeks <br />4.566e-4 months <br /> during surveillance testing, it was found when the recorded l

~ l o la l l tape was played back, the accelerometer traces could not be discerned due to excessive l noise. This placed the unit in the Action Statement of T.S. 3.3.3.3. There was no l lol4l o $ 1 danger to the health and safety of the public or station personnel. The outline tri- l o e l axial accelerometer would have been recorded graphically had a seismic event occurred. l I

. [ o l 7 l l (NP-33-79-129) o 8 l 80 OE CODE SUDC E COMPONENT CODE SUBC DE SU DE 7

o 9 8 9 l X l X l@ W@ l Al@ l Il Nl Sl Tl Rl Ul@ W@ lZ l@

to Il 12 33 18 19 20 RFVISION SEQUENTI AL OCCURRENCE REPORT CODE TYPE N O.

EVENTYEAR REPORT NO.

h a'EuNE L

R 'RO 7 nt 9l l- l1l1l1l 24 26 y

27 l0 28 3j TJ Ll 30 l-l 31 W32

_ 21 22 2J HOURS S B 11 FO bO B. SUPPLI MAN FACT RfR ON PL NT ETH TAKE ACT Zlg ]36g l 0l 0l 0l 0l ] g g g l Al g lT l1 l0 l0 lg ygl34Xlg 3J 35 37 40 41 42 43 44 47 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS h

- li l O ] lThe cause of this occurrence is component failure in that the excessive noise is being l i i generated within the system. The source of noise within the system is being investi- l As of December 11, 1979, l 7 , 7 l gated by I&C personnel under work request WR-IC-100-05-79.

l l i l 3 l l it is believed the scurce of the noise is the battery charger l

1 4 l 80 7 8 9 OTHER STATUS DISCO RY DISCOVERY DESCRIPTION STA S  % POWER

~ '8 W@ l010 0'*@ l "NA l lBj@lInserviceInspection

• A8TiviTY CoSTENT LOCATION OF RELEASE RELE ASED OF RELE ASE AVOUNT OF ACTIVITY

~

l NA l i o Lz_J

@ lz_J@l NA " *

,E eSONum,OS&S NuveEn TYPE oESCRiPTiON @ l llL_l' l '01010 l@l Z l@l"NA "

PERSONNE L iN;u'R'iES NUYBE R DESCRIPTION

)

I j l

~ [TEl8 l90 l 0 Ol@l NA 7 11 12 80 LOSS OF OR DAMAGE TO FACILITY D E SCitlP TION TYPE j

7 i 9 8 9 W @l10NA 80 ISSUE DE SCRIPTION @ Qg}Q{7Q I llllllllllllg; l

7 2 o 8 9 hl toNA 68 69 80 ;;;

419-259-5000, Ext. 290 DVR 79-169 NAME OF PREPARER Ken Aebte PHONE: {

TOLEDO EDISON COMPANY DAVIS-BESSE NUCLEAR POWER STATION UNIT ONE SUPPLEMENTAL INFORMATION FOR LER NP-33-79-129 DATE OF EVENT: November 14, 1979 FACILITY: Davis-Besse Unit 1 IDENTIFICATION OF OCCURRENCE: During performance of ST 5034.02, the seismic m toring system was found to be inoperable The unit was in Mode 5, with Power (MWT) = 0, and Conditions Prior to Occurrence:

Load (Gross MWe) = 0.

On November 14, 1979, at 1200 hours0.0139 days <br />0.333 hours <br />0.00198 weeks <br />4.566e-4 months <br /> during the perfor-h Description mance of STof5034.02, Occurrence: Seismic Functional Test by I&C shop personnel, it was found dis-t at when the recorded tape was played back, the accelerometer traces coul cerned due to excessive noise.

nical Specification 3.3.3.3 which requires the seismic monitoring system to be opera-ble at all tLnes.

The cause of this occurrence is compon-Designation of Apparent Cause of Occurrence:the excessive noise is being generated within th ent failure in that Analysis of Occurrence: There was no danger to the health and safety of the public or to station personnel. The outline triaxial accelerometer would have been recorded The excessive noise within the system graphically had a seismic event occurred.

would have only prevented analysis of the recorded magnetic tapes.

The source of noise within the system is being investigated by Corrective Action: As of December 11, 1979, it is I&C personnel under work request WR-IC-100-05-79.

believed the source of the noise is the battery charger.

Failure Data: There have been no previous similar occurrences.

LER #79-111 1592 204 4