ML20043F629

LER 90-008-00:on 900514,HPCI Sys Rendered Inoperable When Control Power Lost to Min Flow Bypass Valve to Suppression Pool.Probably Caused by Design Problem W/Ge Model CR2940 Sockets.Light Bulb & Fuse replaced.W/900611 Ltr

ML20043F629
Person / Time
Site:	Brunswick
Issue date:	06/11/1990
From:	Harness J, Link W CAROLINA POWER & LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
BSEP-90-0428, BSEP-90-428, LER-90-008-02, LER-90-8-2, NUDOCS 9006150170
Download: ML20043F629 (5)

Text

. - - - - - . .

i.. . ,

g; ;q

: v ,

x

.u

[ - l

(, , - . r; Carolina Power & LigM Company 1

Brunswick Nuclear Project P. O.nBox"10429-

f ,

Southport, NC 28461-0429 June 11, 1990 f .E

, FILE: 'B09-13510C 10CFR50.73 "I? SERIAL: BSEP/90-0428-

.p p -< U.S. Nuclear Regulatory Commission ATTN: . Document. Control Desk-

' Washington,-DC 20555

. BRUNSWICK STEAM ELECTRIC PLANT UNIT l' DOCKET'NO, 50-325 LICENSE NO. DPR-71 o LICENSEE EVENT REPORT 1-90-08 Centlemen:

In accordance with Title 10 to the Code of Federal Regulations, the enclosed Licensee. Event Report is submitted. This report fulfills the requirement for

~

a written report _within thirty (30) days of a reportable occurrence and is in accordance-with the format set forth in NUREG-1022, September 1983.

Ver truly yours,

) kW\A'N 4 L. Harness, General Manager Brunswick Nuclear Project

'WDL/mcg.LTR2 Enclosure cc: 'Mr. S. D. Ebneter Mr. N. B. Le BSEP NRC Resident Office g A LOC h ~

v

f g3 ssUCLEAA CIEWLATORT _ -T APPROyto OMS NO 3166 4104 IISlc 08tti {lBB -

6 x7ti'.t& 4?30/M

./ .

ISTtuAf tD CUADEN l'Est RESPONil TO COMPLv CffM TMit uCENSEE EVENT REPORT (LER)

" " ^ ' ' * ' '*

• Ccl.."i N1i UG A.'o','.'O .' U' " o"E. $1Y.M'TU' i nTCe"."oi AND RtPORTS MAteAGiut NT 9mANCH 194301.U S tsUCLE AR j

8ttGULATORY COWut&540N 1s ASMtssGTON. DC 306%. Amo TO TMt P APERwORK REDUCTION PROJEC1 431604t0ei. Ce r tCE 08 MANAGEMINT AteD DUOGET,WASHINGTOtt.DC 2%C3 DOCRti esUasta (2) ' AWE GI

1. ACILt'(y esAa85 til

' Brunswick Steam Electric Plant 0 l5l0tol0l3l2 51 1 lOFl 0 l4 TiTCG HPCI Inoperability - Loss of Control Power to Minimum Flow Valve OVENT DAf t (Si Ltn n Unasta (Si i AGPOAT DAtt (71 OTHER S ACILITits INv0LvtD tel DOcati ssuust msi

u $*,j,'

sacniTv hauts heONTM OAv YEAR vtAm 0 "'

, j,$ MONTH OAV vtan Brunswick Unit 2 01610 l 0 l 0 t 3- ]Q  ;

0l5 l l4 9 0 9l0

~

0 l 0 l8

~

0j0 Oj6 1l1 9l 0 a 3 o,o,o, , ,

THet RtPORT 18 SUOMITTED PUR$UANT TO TMt RLoutfttMSNTS Of 10 Cf R l icaera eae er meg of rae 8er'e*'af f till Opt nAf seeO MOOR W I N 402tt) 29 4054 1 90 Thlt2Hev) 13.71tbl to esteittiul to setsHit to T3taH2Het 73.714al POuta ~ ~

~

' u.,wH:H,e> orntn ts.n*, A.. nr 30 esmHiHei m.seNHai ls 1 I 01 0 20 408tsH1 Hell to.79teH2iul to 73teH2He661HAl J56A H.,

g, ' '

4 H, ,0.,

. ,m H,,,,

.0.,,M H H to 736sH2Hal 30 4Winit1Het 94.73telt2 Hell LICleSit CONT ACT FOR THIS tlR (12)

NAgg TEtt*HONI seUMSSR ARE A COOT Wayne D. Link, Senior Generation Specialist 9 ; 1 [9 4 5;7 -l2 g i ;0;5g4 ,

COMPLif t ONE LINE PDA ( ACH COespoe6ENT F AILURI Ot9ChiettilN THIS REPORT tt31

~

h CAust SYSTEM cow'OhtNT "#)$'g"0 "k'o$Pn'$II CAUst sy sTt u COuPONINT "'"$'g AC m*onTAgg o pn

. m l l 1 l l t i l l I I I l 1 .{

I I I I I I I I I I I I I I WONTM OAV vtAR I aUPPLEMENT AL REPORT lxPtCTto (14:

I sueuissioN TtS (19 ree tornenere 9x91(180 SUOnetSSIOne DA Til eeO l l l A mCTu-,,e... ...e .._,..N ..,,. . - _. ,11.,

Unit 1 was operating at 100% power. At 1057 on 5-14-90, the Unit 1 High Pressure Coolant Injection system was rendered inoperable when control power was lost to the minimum flow bypass valve to the suppression pool, E41-F012 while changing the breaker compartment closed indicator light. The light bulb and blown control power fuse were replaced and the valve was electrically stroked .and returned to service. No further corrective actions are planned.

The safety significance of this event is minimal. The plant is analyzed for a HPCI failure and the Automatic Depressurization and Low Pressure Coolant Injection systems were available to serve as a backup to HPCI.

A similar loss of control power was reported in Licensee Event Report 1-89-020.

ex.C e m

gei,, APPROvtD oms feo 3160 4104

, i IKPiGES 4/3042 UCENSEE EVENT REPORT (LER)  %%','EO'#M/cPJ'!;O",5/ ? .#'l'L'l T."Wu's '

^ '

TEXT CONTINUATION jf4"l#f"M2MW'."dCSjd  !"!Mn PAPI WO R 10 nJ (3 4 04 0 IC

, Of MANAGEMENT AND SUDGET,WA$HINGTOh. DC 20603 FACILITY ISAME IU DOCKET NUGABER (2) Lth hVMOth 16) PA06 (31

"*" wa t'm aft wa Brunswick Steam Elect ric Plant.

o j5 l0 lo l0 l 3 l2 [ 5 910 -

0 l0l 8 -

0l0 0j2 0F 0 l4 r$xt ,, ,,,,, ,,,,,, . , _ ,

EVENT Unit 1 High Pressure Coolant Injection (HPCI) system was rendered inoperable when control power was lost to the minimuminstalling flow bypass a valve to the suppression pool, E41-F012, while replacement indicator light bulb at the Motor Control Center (MCC) breaker compartment.

INITIAL CONDITIONS Unit 1 was operating at 100% power. The Automatic Depressurization system (ADS), the Residual Heat Removal / Low Pressure Coolant Injection (RHR/ LPCI) system, the Core Spray (CS) system, the High Pressure Coolant Injection system, and the Reactor Core Isolation Cooling system were operable.

EVENT DESCRIPTION At 1057 on 5-14-90, an annunciator, A-1 5-4, HPCI Valves Motor Overload, was received in the Control Room. The annunciator was caused by a loss of control power to E41-F012. A loss of control power will prevent automatic or electrical opening of the minimum flow valve. The vendor had previously indicated that operation of the HPCI pump and turbine without a flow path for greater than 30 seconds could possibly damage the HPCI equipment. HPCI, therefore, was determined to be inoperable until control power was restored to E41-F012.

The Senior Auxiliary Operator (SAO) noticed, while conducting rounds, that the green (closed) indicator light for E41-F012, located on MCC 1XDA, Compartment B24, was out. The bulb was removed and a new one installed. Before completely inserting the replacement bulb (approximately two turns inserted), it flashed.

This bulb was removed and another one was installed. After doing this, the SAO noticed that the closed indicator light was still extinguished and suspected that control power had ber ost.

Work Request / Job Order (WR/JO) 90-AITJ1 was writts i, Limiting Condition of Operation (LCO) Al-90-0818 was established, and Clearance (Clr) 1-90-0162 was placed on the breaker compartment.

Instrumentation and Control (I&C) technicians found one of the two control power fuses blown and replaced it. The socket was inspected for defects and found not to be a contributing factor.

The breaker was energized at 1358. A 4-hour Red Phone Report was made to the Nuclear Regulatory Commission at 1443. The valve was f8RC Feem 3SSA 16491

WW E W.S.00UCLS1R RitutaiE4Y' M

~

i least , APPROvtD Out 8e0. 31604104 l, e1 (KPl7.t3 4/300 LICENSEE EVENT REPORT (LER) '32.'11%',,u"cM,7,"J'!?o"*',,%C.T.' ,"D'.".'a'!

C TEXT CONTINUATION i?,77".%'i?.^itM '#f',"d!,'c'UljdG"' MMn M.W R.'oi?'7.Tu? M,^= Tc?"J.'J"A 0?li Of ANAGE. TNT AND DVDGET, WASHINGTON DC 30603-PACILtTV IBAABE tis DOCKtf BIUSSSR 42)

Lth 88UNBth (6) PA04 (3) vsaa .

" d' O l'#.W Brunswick Steam Electric Plant i rtre,, - ., = me i.- ama w ii7>

0 l5 l 0 l 0 l 0 l 3 l 2l 5 40 -

0l0l8 -

010 Ol3. OF O!4 returned to service at 1518 after electrical stroking of the valve was completed satisfactorily.

EVENT INVESTIGATION /CAUSE A similar loss of control power, reported'in Licensee Event Report (LER) 1 89-020, identified a potential design problem with General Electric Model CR2940 sockets that allowed the negative socket coil to come into contact with the positive socket , tab during bulb removal' due to coil distortion. At that time (Oct. 1989),

Technical Support investigated the feasibility of replacing the GE sockets with a Westinghouse bayonet type socket. - The decision was made to replace the sockets with the same GE design socket since the suspect sockets had been in service approximately 15 years.

An inspection plan was developed and implemented to identify those breakers which could result in a system failure due to a socket failure. Since then, the sockets have been. replaced on Unit 2 and identified, but not replaced, on Unit 1.

Due to past problems with the MCC electrical sockets, electrical engineering became involved in the investigation. In this' case, the socket was determined not to be a factor. The failure of'the

• light bulb is being attributed to the manufacturing process.

CORRECTIVE ACTIONS TAKEN The light bulb'and fuse were replaced. E41-F012 was electrically stroked satisfactorily and HPCI was restored to service. No further corrective actions are planned.

EVENT ASSESSMENT The nafety significance of this event is considered to be low.

The plant is analyzed for a HPCI failure and the Automatic

. Depressurization and Low Pressure Coolant Injection systems were available to serve as a backup-to HPCI. The failure mode of the light bulb is considered to be an isolated case.

00RC 7erm 306A (649) i

_'*s tXPtIt$ 4/3tW93 '

i LICENSEE EVENT REPORT (LER)  : '#st'1,%7&",nfog'yo"n,%eg.l,7,w,s,u,,,wi,g ,

.e^

.* ' ' , -* TEXT CDNTINUATl3N  !?,74"g,'S'##;Eo',"d','d,"f,'jg M , L",' t,Mn --

UP,WEL*i""Naf,^!"a'ni3LW'a??? +

• - 07 MANA0tMENT AND 300Gg7,WASMlWOTON. DC 20003. -

MIYY M III - DOCattsepteth(3) - LORNUMBtn m) PAet (31  !

stoutNisA6 ',nsv eson ...

vtan """"" """""

r l

l BYtinswick Steam Electric Plant 15 l l l l 3 l 2l 5 9 l 0 0l,0 l 8 oF 0l4 0 l 0 ' 0l 4 To:T o m . w ,, ,,,, e ,,,,,, ,, w ny, i EIIS Codes Residual Heat Removal Low BOs- i I

Pressure Coolant Injection

.I Core Spray BM.  ;

Reactor Core Isolation BN-  ;

I Cooling l Automatic'Depressurization None High Pressure Coolant BJ-Injection None  !

Socket y

Indicator Light IL l t

Annunciator ANN 1

. Fuse .FU-  !

l!

valve v Pump P 4

Turbine TRB l

L.

=Ac r.= assA i$ser E___u___. ___________'______________________________._______.__ , _ ,

_ ,