ML20028H686

LER 90-014-00:on 901223,containment Spray Sys Train B Pump Discharge Pressure Indicator 3PI-0303-2 Did Not Display Correct Pressure Reading.Caused by Metallic Particle Near Feedback Coil.Transmitter replaced.W/910122 Ltr

ML20028H686
Person / Time
Site:	San Onofre
Issue date:	01/22/1991
From:	Krieger R SOUTHERN CALIFORNIA EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-90-014-02, LER-90-14-2, NUDOCS 9101280085
Download: ML20028H686 (2)

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Southem Califomia Edison Company SAN ONorHE NUCLEAR GENLHATING STATaON P. O. DOX 100 SAN CLEMENTE, CAL IFOHNIA92674 0128 R. W. KRIEGER TettPHONE STAllON MANAGGil (Tiet 3694795 Janua.y 22, 1991 U. S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555 Subj ec t : Docket No. 50 362 30 Day Report Licensee Event Report No. 90 014 San Onofro Nucicar Generating Station, Unit 3 Pursuant to 10 CFR 50.73(d), this submittal provides'the required 30-day written Licensco Event Report (LER) for an occurrence involving an inoperable Post Accident Monitoring Instrument. Our investigation into this occurrence

.is continuing. The results of this investigation, including the root cause and corrective actions to prevent recurrence, will be provided in a suppicment to this LER. Neither the health nor the safoty of plant personnel or the public was affected by this occurrence.

If you require any additional information, please so adviso.

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Enclosure:

LER No 014 cc: C. W. Caldwell (USNRC Senior Resident Inspector, Units 1, 2 and 3)

J. B. tiartin (Regional Administrator, USNRC Region V)

Institute of Nuclear Power Operations (INPO) y 9101280085 910122 )/

PDR ADOCK 05000362 /

S PDR

_. _m.... . . _ _ . _ _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ . m. m _ _~ ._- _ _ _ _ __ - _ _ _

e-0 tICENSEE EVENT REICRT (L*'R)

Facility Narus (1) Docket Number (2) Inte 3) l- ,

SAN ONOFRE NT LEAR CENERATING FTATION. UNIT 3 Ol $t 0101Ol$l612 1 ef 0 1 Title (As j CONTAINMENT SPRAY SYSTEM PRESSURt INDICATOR INOTERABLE DUE TO FAILED PRESSURE TRANSMITTER rvrut nAtr mi t rn Mare .g i trmettutt tti m en tettt"tre tuvntven tai Month Day Year year 'ff' ' , 8'CU*k f/j "fu,lN"

i Month Day year '*""*" "'"' ""'

01 M O! 01 Ol l l NONE 1l2 2l3 910 910 0l114 0!0 011 212 911 of Sl 01 01 01 l l TNIS REICRT IS !.UDti TTED FURSUANT TO THE REQUlkEPENTS OF 10CFR OFERAU NO (Chock om er more of the followina) (11)

E ID 20.402(b) 1 ,,,,,,, _,_ 20.405(c) ,,,,,,, 50.73(a)(2)(tv) ,,,,,,,, 73.71(b)

KHEk 20.405(a)(1)(1) ,_,,,, 50.36(c)(1) _,,,,, 50.73(a)(2)(v) _ 73.71(c)

LEVEL ,,,, 20.405(a)(1)(11) ,,E., 50.36(c)(2) _ 50.73(a)(2)(vii) Other (Epocify in (10) 1 1 010 ,,,,,_ 20.405(a)(1)(111) ,J.,,, 50.73(a)(2)(1) ,,,,,,, 50.73(a)(2)(viii)(A) ,_, Abstract below snd

///////////////////////// ._,,,

20,405(e)(1)(iv) ,,,,_

50,73(a)(2)(11) ,,_,, 50.73(a)(2)(viii)(B) in text)

! ///////////////////////// ,_ 20.405(a)(1)(v) ,,,,,,,, 50.73(a)(2)(iii) ,,,,_ 50.73(a)(2)(x)

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, /////////////////////////

LICENSEE CONTACT FOR THIS LER (12)

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TELEPHONE NUMBER Name AREA CODE R. W. Krieren Station Menarer 7 l1 14 31 61 el -l 6l 2l $l 5 COMPLETE oNE LINE FoR EACH COMPONENT fan.URE DESCRIBED IN THIS REPORT (13)

CAU3E SYSTFM CQiPONENT MANUTAC- REPORTABLE

" " CAUSE SYSTEM COMPONENT MANUFAC- REPORTABLE TURER TO NPRDg_ /////// TURER To NPRDS //////

X BlE I l Plt Fl il Bl 0 YES /////// l i l l l I l //////

1 l I l 1 l 1 n/H// l I l l I i l H///j, SUPPLEMENTAL REPORT EXPECTED (14) M nth Day l Year Expected Submieaion XX !Yes(Ifves. comotete EXPECTED SUTHISSION DATE) l ,,,,, NO Date (15) 011 219 911 ABSTRACT (Limit to 1400 spaces. i.e., approximately fifteen single-space typewritten lines) (16) on 12/23/90, with Unit 3 at 100% power, Containment Spray System (CSS) Train "B" pump discharge pressure indicator 3PI-0303-2, was determined to be inoperable due to its failure to display the correct pressure reading. This instrument is a Post Accident Monitoring Instrumentation (PAMI) component and as such is subject to the requirements of Technical Specification (TS) 3.3.3.6, which allows for the inoperability of PAMI equipment for up to 7 days. Our investigation concluded that 3PI-0303 2 became inoperable on 12/12/90 when the associated pressure transmitter 3PT-0303-2, which provides the input to 3PI-0303 2, failed during subgroup relay testing associated with the CSS. This represents a condition prohibited by TS 3.3.3.6, since 3PI-0303 2 was inoperable for greater than 7 days.

Inspection of the pressure transmitter revealed a small foreign object (i.e.,

metallic particle) located in the vicinity of the feedback coil. It is believed that the particle resulted in the jamming of the feedback coil, and thus

, produced a pressure indication which was substantially greater than actual pressure (approximately 400 psig versus 25 psig). The transmitter was replaced and the indicator returned to operabic status on 12/25/90.

l- Abnormally high pressure in this portion of the CSS is not alarmed or

( annunciated in the Control Room (CR). However, SCE is investigating the reasons that the instrument failure was not identified more promptly. The results of that investigation will be included in a revision to this LER scheduled to be

issued by 1/29/91.

l CSS Train "B" pressure indicator 3PI 0303-2, which is used for indication purposes only, would not have affected the ability of the system to fulfill its safety function. In addition, Train "A", including the required PAMI, remained operable during this event.

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