ML19256G569

LER 79-130/03L-0:on 791205,during Reactor Water Level Instrument Functional Test & Calibr,Switch 2B21-NO42A Found Out of Tech Spec Limit.Caused by Instrument Drift. Instrument Calibr & Tested

ML19256G569
Person / Time
Site:	Hatch
Issue date:	12/26/1979
From:	Nix R GEORGIA POWER CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19256G563	List: ML19256G562 ML19256G569
References
LER-79-130-03L, LER-79-130-3L, NUDOCS 7912310468
Download: ML19256G569 (2)

Text

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (7 77)

LICENSEE EVENT REPORT (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

CONTROL B' LOCK: l I

l l l l I lh 6

[ l Gl Al 7 9 ElLICENSEE Il Hl 2CODE l@l 0 l 0 l 0 ] 0 l 0 l LICENSE 14 15 0 l 0 NuMUEH l 0 l 0 l 0 l 0 'l@l 25 426 l 1 LICENSE l 1 l 1TYPE l 1Jol@l57 CATl 58 g

CON'I 7

o 1 8

30RC 60 lLl@l0l5l0l0l0l3l6I6l@l1l210I5l7I9l@l1l2l2I6I7l9l@

61 DOCKET NUYBER 68 69 EVENT DATE le 75 REPORT DATE 80 EVENT DESCRIPTION AND PROBA8LE CONSEQUENCES h 10121 l While performing Reactor Water Level (ADS) Instrument Functional Test and Calibration,l lo l3l l HNP-2-3251, 2B21-N042A was found to be out of Tech Specs limit. The switch actuated l l o 14 l l at 10.2" H90 reactor level; Tech Specs limit is 312.5" H90. The switch, 2B21'-N042B, l o s in the redundant channel was operable and within tolerance. There was no e f fect on l lo is l l the environs. This is a non-repetitive event for this instrument. l loIiI o a l I DE CODE SUSCO E COMPONENT CODE SUB dE SU E g

7 8 9 i Il Bl@ W@ l Z l@ l Il Nl Sl Tl Rl Ul@ ]@ l Zl @

10 11 12 13 18 19 20

,,,, SEOUENTIAL OCCURRENCE REPORT REVISION EVENTYEAR REPORT NO. CODE TYPE N O.

LER

@ yug/RO at

_ 21 1719I 22 l-23 1113l01 24 26 W

27 I 01 31 23 29 I LI 30 l-l 31 10 1 32 ,

NKTN ACT0 O PL NT MET HOURS S B ! FO d B. SU PLI MAN FA TURER LE_j@lZl@ 34 lZl@

35 lZl@

36

[0 l 0 l 0 l 040l [Y 41 l@ l42Yl@ l43N l@ lG l0 l8 0lg 44 47 3J 3/

CAUSE DESCRIPTION AND CORRECTIVE ACTIONS h i o l The cause of the occurrence has been attributed to instrument drif t. The instrument l li li l was calibrated and a functional test was performed satisfactorily. 1 i 2 I I

i a l l l

1114 l l 7 8 9 80 STA S  % POWER OTHER STATUS 615 OV RY DISCOVERY DESCRIPTION W d @ l1 0l0l@ NA l lBl@l Performing surveillance l A TIVITY CO TENT AMOUNT OF ACTIVITY LOCATION OF RELEASE NA l 7

1 6 RLLEASE@D OF RELEASE [2]@l 8 9 10 tt NA 44 l

45 80 PERSONNEL E=POSURES NUMBER TYPE DESCRIPTION NA l i i 1 01 01 Ol@l Z l@l PERSONNEL INJURIES NUMBER DESCRIPTION NA 7

i R l0 0l 0l@l 9 1 12 l

80 LOSS OF oR DAMAGE TO FACILITY TYPE DESCRIPTION

' 9 NA l L_ZJ@l 80 7 8 9 10 NA llllllllll [!l}

2 o ISSSUE L l @ DESCRIPTION l R* T. Nix 7 O U1 12-367-7781 o NAME OF PREPARER PHONE:

NARRATIVE REPORT Ceorgia Power Company Plant E. I. Hatch Baxley, Georgia 31513 Reportable Occurrence Report No. 50-366/1979-130

, While performing Reactor Water Level (ADS) Instrument Functional Test, 2B21-N042A level switch was found to be out of Tech Specs limit. The switch, 2B21-N042A, actuated at 10.2" H,0 reactor level; Tech Specs limit is 212.5" H2O reactor level. The switch, 2B21-N042B, in the redundant channel 4 was operable and within tolerance. The reactor was at 100% steady state power. The operation of the plant was not effected. There was no effect on the environs. This was a non-repetitive event. The cause of the occurrence has been attributed to instrument drift. The instrument was calibrated and functionally tested satisfactorily. Unit I and Unit II utilize this type of instrument, Yarway .Model 4418C, in the ADS, LPCI Permissive, Recirc Pump Trip Logic and Nuclear Steam Supply Shutoff System. These instruments do not have a generic drif t problem.

P 1658 119

.