ML20042A530

LER 82-003/03L-0:on 820224,differential Pressure Switch DPIS 2-1360-1B+ Failed to Operate.Caused by Instrument Drift.Switch Recalibr & Tested Satisfactorily

ML20042A530
Person / Time
Site:	Quad Cities
Issue date:	03/11/1982
From:	Reynolds S COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20042A522	List: ML20042A521 ML20042A530
References
LER-82-003-03L-02, LER-82-3-3L-2, NUDOCS 8203230526
Download: ML20042A530 (2)

Text

__ - . _ - .-_ . ~ _ - - - _ . . . . . - ~ . ..

NRC PCRM 364 U. S. NLCLEA2 MEGULATO2Y COMMISSION 17

• 77)

LICENSEE EVENT REPORT CONTROL 8 LOCK: l i

l l l l l 6

lh (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATIOM F

o i ll$ 9l L l LICEN$tt Q l AC001 l D l 2 l@l 0 l 0l Ol -l0 14 15 l 010 l - l 0 l 0 l J$O l@l LICENSE NwVetR 26 4l ll 1l 1l 1 l@(

LSCENSE Tvrt 40 47 CATl tel@

CON'T L9LJ8 ."EE I L j@l 0151 ol 010121 61 sl@LO_l 2 l 2 I al 8l 21@l013 I i I i I 812.0l@

14 7 60 61 DOCK ET NUMetR 68 43 EVENT OATE 15 REPORTD475 EVENT DESCRIPTION ANO PROS A8LE CONSEQUENCES h i ITTTl l On February 24, 1982, while performing the quarterly RCIC Steam Line High Flow __

l 2

o 2 l Calibration and Functional Test, QlS 18, OPIS 2-1360-1B+ failed to operate. I gl This switch is associated with the DPIS 2-1360-1B differential pressure cell I i

lo is t I which Isolates the RCIC steam line on high flow. The redundant di f ferential I gl pressure cell DPIS 2-1360-I A was found operable and would have isolated the l j

[T{T) l RCIC steam line on high flow. At the time of the calibration, Unit Two had l been shutdown since January 18, 1982, and Primary Containment was

I o la i I not in offect. I i , , , so E CODE Suec Of COMPONENT C006 $UeC004 50 t g

i, e l C l E l@ W@ W@ l 1l NlS lT lR lU l@ l S l@ g g 9 to 11 12 13 1e av Ju

,_ SE QUE NTI AL CCCU A RE NCE REPORT 4tVt5 EON Lim RO EVENTYEAR Rt'ORTNO Coot TYPE No O17 ,afga r l 8l 2i v

l-l n

l 0 l 0l 3l y 10 l3 l lL l [---J [0,,j n 24 is v n n u v n K N AC ON ON PL NT Mtf HOURS S e TT POR b 8 $UPPL1 MANUPACTURtp IEl@[C,,,,j@ [Z_j@ lZl@ l 010l 0l 01

(,Y j @ lYl@ [_,lij@ l44B l 0 l 8 l O47 l@

' 3J J4 36 J6 3 40 el 42 43 l CAUSE DESCRIPTION AND CORRECTIVE ACTIONS h j gl The cause of this occurrence was instrument drif t of the DPIS 2-1360-1B+. l l

gi di f ferential pressure swi tch. The switch was recalibrated and tested I l mI satisfactorily. As a resul t of a recent increase in the tendency for these l

' 1 I switches to drift. all Unit One and Unit Two high steam flow di f ferential I l i 14 I I pressure switches will be renlaced like-for-like, 1 7 8 9 90

$TA 5  % PQWE R OTHER$TATU$ l$ Q RY OtSCoVERY CESCRIPTION

[TTTl l Gl@ l 0l 0l 0l@l" NA l lB l@l Quarterly instrument Calibration l ACTiviiv Co' Ort NT Ritt Asto oP Rite Ast toc ArioN cP Rtet Ast @

I' IIl [,Z,,,) @ [,,,Zj @ l AvouNT NA op ACTivirv @ l l NA l

! nRsoNNll E PosSts NUV8t R TYPE OtSCRIPYiON Li_Lj . l 0 10 10 l@[, Z.j@l NT l PERsoNNE't.N;ubs "

Nuvet R etsCR4 Tion @

J i a 8 9 lo l o l o l@l12 11 NA 80 I

'rD't i s'C7^P r'o'N '' " @

liI9I[Z,J@l NA l P G 9 10 40 i Of 5CRIPTioN

• W 'ssut ' Na I i l l l l l l 1 l l' 1112

' 82"03230526 820311 PDR ADOCK 05000265 " '"'i

• S PDR  : Reynolds , soys. 309-6r>4-2241. ext. 177 E

1. LER NUMBER: LER/R0 82-3/03L-0

11. LICENSEE NAME: Commonwealth Edison Company Quad-Cities Nuclear Power Station ill. FACILITY NAME: Unit Two IV. DOCKET NUMBER: 050-265 V. EVENT DESCRIPTION:

On February 24, 1982, while performing QlS 18, RCIC Steam Line High Flow Calibration and Functional Test, it was found that switch DPIS 2-1360-1B+

would not operate. Technical Specification 3.2.A. (Table 3.2. l .) requi res that the trip setting be less than or equal to 300 percent of rated flow.

VI. PROBABLE CONSEQUENCES OF THE OCCURRENCE:

The differential pressure cell monitors flow in the RCIC steam line in order to detect a potential break in the line. At 300 percent of the rated flow, o signal is required to be initiated to give a Group V isolation signal. Each of the two redundant dif ferential pressure cells, DPIS 2-1360-IA and IB, has two switches; one each in the positive and negative direction. The negative switches sense a low pressure sensing line break while the positive switches sense both a high pressure line break and high flow (DP). Any one of these four switches is capable of initiating the Group V isolation signal. The DPIS 2-1360-1A cell was found to function properly, thereby, ensuring the isolation would have been Initiated had a steam line break occurred.

Vll. CAUSE:

The cause of this occurrence was setpoint drif t of the high side switch, it is a Bellows Type, Model 288 Barton instrument. The switch was last calibrated and functionally tested on November 25, 1981.

Vlli. CORRECTIVE ACTION:

The switch was adjusted and recalibrated to trip at 186" H2O (229 percent of rated flow) and functionally tested satisfactorily on February 24, 1982.

Several of the RCIC high steam flow isolation differential pressure switches have recently shown an increased tendency to drift. This trend has been attributed to normal contact wear. As a precaution, all Unit One and Unit Two RCIC high steam flow micro switches will be replaced with new switches of the same type, if they have not been replaced recently.