ML20009C638

LER 81-016/03L-0:on 810618,water Level Instrument Surveillance Found LIS 263-57A Tripping Above Tech Spec Levels for Low Level Scram & Low Water Level Isolation. Caused by Instrument Setpoint Drift.Setpoint Adjusted

ML20009C638
Person / Time
Site:	Dresden
Issue date:	07/08/1981
From:	Schroeder B COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20009C634	List: ML20009C633 ML20009C638
References
LER-81-016-03L-01, LER-81-16-3L-1, NUDOCS 8107210304
Download: ML20009C638 (2)

Text

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u.s. NUCLEAR REGULATORY COMMISSION

' (7 77) t LICENSEE EVENT REPORT

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t CONTROL 8 LOCK: l l l l l l lh (PLEASE PRINT OR TYPE ALL REQUIREO INPORMATION) t l 0 l 819l l I lUCENSEE 7

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uCENSE TYPE 40 l

CMT -

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10111 7 8 60 61 oOCKET NUMSER 68 88 74 75 80 EVENT DESCRIPTION AND PRO 8A8LE CONSECUENCES h 10 l 2 l l While performini monthly Rx water level instrument surveillance. LIS 263-57A was found l ITTTl I to trip at 69.5 inches W.C. for low level scram and trip at 116 inches for low water l io l4 l l level isolation which exceeds the Tech. Spec. Limits of 66.8 inches and 114.5 inches I ,

I o I s l l respectively. Safety implications minimal because remaining three switches were all .g lo l6 l l operable and would have performed as designed. There was no effect on public health or ;

o ,7 ; [ safety. Previous occurrences

50-249/80-023/03L-0 and 80-024/03L-0  ;

, 101811 I 7 8 9 So CoE o su C E COMPONENT CODE SUS ode SU E 10191' 7 8 l Il Al@ {@ {@ lIlN lS lT lR lU l@ l Sl@ lZ l@

9 ~9 11 12 13 18 19 20 SEoUENTIAL OCCURRENCE REPORT REVISION LER EVENT YEAR REPORT NO. CODE TYPE No.

@ yung/Ro l8 aEP l 1l l--.] l0l1l6l l/l l 0l 3l lLl l-l l0l

_ 21 22 23 24 26 27 28 29 30 31 02 EN AC ON P T ME HOURS 22 38 i POR 8. SUP L MA UF RER l E j g g g lSZ jg 33 34 J l8 3

Zlg l0l0l0l 37 40 l lN lg 44 lY [g l N lg 42 43 l G l 0 [ 8 l 0 lg_.

44 47 -

CAUSE DESCRIPTION AND CORRECTIVE ACTICNS h g i g o l l The cause of event attributed to instrument setpoint drif t. Instrument was inspected [

g1 i,, l and nothing abnormal found. Low level scram setpoint was immediately adjusted to 63 ' [

g inches and a repeated test showed the low low isolation to return to 112.7 inches. Rx g

low level ECCS switches will coticinue to be tested monthly per DIS 500-2. g gl . 'l 7 8 J 80 A  % POWER OTHERSTATUS l Y OtScoVERY DESCRIPT10N ii is I trJ@ l 019 I 7 l@ln N/A l l3l@l .Surveillance Tests [

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' JnvirY CanNT P.EuASEo eP RELEASE LOCATION oF RELEASE AMouNTo, N/A ACTIVITY l @ l N/A l l1 l68l 9l Zl @ lto2 l@l 7 11 44 46 80 ,

PER$0NNEL EXPOSURES , i NUMSER TYPE CESCRIPTION l i 171 l0 10 l0 l@l Z l@l N/A l

' ' ' ,ERSoN~E N JiES " '

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~uMSER oESCRiPTioN@  ;

li Ia 8l !9 01 0l 0l@l12 N/A l 7 11 80 L oP CR CAM To PACluTY __

fiTil l Zi@l N/A l_

NRC USE ONLY i UE DE CRiPricN @ D o!ok$9 7

2 o 8 9 lNfhlto N/A PDR _.}

68 69 llIIIIliIIIIII 80 3 NAME @F PRFPARFR - PHON F*

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DEVIATION REPORT  :

. DVR NO.

Commonwealth Edison STA UNIT YEAR N O.

o 3 35 PART 1l Tl TLE OF DEVi ATION OCCU RRED 6-18-81 1400 Unit 3 Reacter Vessel Low Level Half Scram and Low-Low Isolation o ,75 7,yg SYSTEM AFFECTED 500 PLANT CONDITIONS TESTING Rx Protection "

MODE PWR(MWT) , LOAD (MWE)

DESCRIPTION OF EVENT Whila conducting routine surveillance DIS #500-2 on LIS 3-263-57A, it was found that the low lcvel scram was set greater than 66.8" W.C. and the low-low water level was set greater than 114.5" W.C.

DESCRIPTION OF CAUSE '

Test eauipment checks out OK; cause unknown.

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' T:iTHER APPLICABLE INFORMATION Riest low water level half scram from 69.5" W.C. to 63" W.C. and a repeated test showed the low-low isolation to return to 112.7" W.C.

DR NO. WR NO.

EQUIPMENT YES g ggg FAILURE Q NO N/A N/A # RESPONSIBLE SUPERVISOR DATE PART 2 l OPERATING ENGINEERS COMMENTS The level switches were immediately recalibrated and repeatibility was verified.

SAFETY-TYPE OF DEVIATION EVENT OF POTENTIAL TECH SPEC NON-REPORTABLE ANNUAL RELATED REPORTABLE OCCURRENCE PUBLIC INTEREST VIOLATION CCCURRENCE REPURTING WR ISSUED 14 DAY 10CFR21 VES X YES X l 30 DAY NOTIF1 CATION _

NO NO y

--! 6.6.B.2.a REPORTABLE CCCURRENCE ACTION ITEM NO. PROMPT ON-SITE NOTIFICATION

" 0 R. M. Ragan 6/19/81 11:30 REX 81-16/03L-0 TlTLE DATE TIME

( TITLE CATE TIME 24-HOUR NRC NOTIFICATION PROMPT OFF-SITE NOTIFICATION TPH F. A. Palmer 6/19/81 12:40 l _ REGION IIi DATE TIME TI TL E DATE TIME ,

TGV REGION Ii1 & DOL CATE TIME TlTLE DATE TIME  ;

RESPONSI BLE COMP ANY O FFI CER I N FO RMED O F 10 CFR21 '

CONDITIONS AND THEI A CEPO Ar TO NPC

• TITLE DATE TIME i REVI EW AND COMPLETED Michael Wright _

6/19/81  !

CPERAT I NG ENGI Nt.tj / /

CATE .

I AC BY STATION REVIEW jg gg j DATE # ~N '

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j RESOLUTION APPROVED AND AUTHORI ZED FOR DI STRI BUTION W

S T ig#4 SUPERINTENDENT 0

/ SATE

/

l 86*Sf7' fC-77 (FORM tS-52**)

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