ML20071G327

/03L-0 on 781124:during Shutdown Cooling Interlock Test Noted That PC-105B Was Not Operating.Caused by Valve Closing Relay 94-347/348 Not Being Wired to PC-105B; Inadvertently Disconnected in 1977

ML20071G327
Person / Time
Site:	Fort Calhoun
Issue date:	12/22/1978
From:	Mehaffey R, Gordon Peterson OMAHA PUBLIC POWER DISTRICT
To:
Shared Package
ML20071G324	List: ML20071G321 ML20071G327
References
LER-78-042-03L, LER-78-42-3L, NUDOCS 7812290228
Download: ML20071G327 (4)

Text

- _ _ .

LICENSEE EVENT RF. PORT

-y .'.7cL aLOcx. I 1

I I I I 1 6

l@ nLEAss PauNT OR TYPE ALL I!ECUIRED INFOi!MATloN) l o I - l l " I r I T' l c ! s l I l@l o I o 10 l o I o I o I o l 0 l o l o i o l@l k 1111l111]@l l lg 7 s 9 uCEssEE = =E ia :S uCENsENuueEs :3 . act:,3E v , 3a 37 Ca; 3, CON'T lclii

"'.',"y

l L @l O f S l 01010121815 l@lllll2lhl?18l@l112lolel~I

l@

3 60 61 DCOKET NLMBER 68 69 EV ENT O ATE 74 75 AE809T OATE dJ EVENr DESCRIPTION AND PRC8 ABLE CONSECUENCES h l o' 6 2 l lDuring the parfor w ce of shutdown cooling interlock test (ST-SDC-1) it was discoveredt i o e a i I that PC-1053 was not operating. Further investigation showed relay 9h-3h7/3h8 (the l I o i A I l valve closing relay) was not vired to PC-1053 and was inoperable since the 1977 l lo46; } Refueling Outage. The redundant shutdown cooling interloch PC-105 was operable duringl l0t6l l this period. l l 017 l l l t o ia l ! - I

es 3 SYSTEM CAUSE CAUSE COMP. vatyE CODE COCE SUSCOCE COMPCNENT CODE SueCODE SUBCOCE

7 i:19l 8 9 l El El@ 10 11

@ 1;

@ lR lE ll IA lY IX l@ @@ W @

13 18 13 20

,,,, SEcufNTIAL cCOUR RENCE REPCRT REV'SICN gg e EVENT YE AR mE*CRT NC. COCE vpE NC.

@, age,go g IT 18 I l--J l o l h 12 I lA I ol ?l ILI l' I Of

_i 22 :2 24 a  ::  := a ao si :2 ACTtON . FUTURE EpsECT SMUT 0cWN ATTACMMENT N*m O 4 PatME COMP. COM*CNEN*

TAKEN ACTICN ON PLANT METHCO hours -- SUSMITTED FORM aus. SUP*LIEm MANUS AC 1,;RER IFl@izl@ Izl@ 12 l@ I o 10 l o l o l I44 Yl@ Ll1@ l43Al@ l ci of 81 (47 3-33 34 25 . 36 de_ 40 42 ais CAUSE CESORIPTION AND CORRECTIVE AC*lCNS h ji i o , l During installation of Pcver Operated Felief Valve Modification du-ine the icT"  !

i,., Irefueling cutare, relay 9h-3h7/?h6 was inadve- entiv disee ne ai f-rn 00-102 . *4e 1 l

t., il error vas not .Stected prier te subsecuent unit operatien since it was no- kncv- a- I

[- j jthe a -kat the shutdevn cocline pressu~e interlock sve-a- kd keen effected. U:c- f i .! Idiscovery redundant interlock vas provided and both inter 10cks tested satisfactorilv. I 7 3 3 40 pactLITV a ME* WOO C8 STATUS %PCWER QTHER STATUS - CISCOV ERY OISCOVERY OES0miPTICN 4-i li i t al 5W@ l 01010 7 to l@l HA 12 is 44 l3l@l as as Surveillance '"est so l

ACTIVITY CONTENT

=ELEASEs CraELEASE Av0uNTCs Ac tvi Y --

LO:ATION Os aE .EASE --8 iiisiIZlhl2!@l d 3 10

'EASCNNEL EXPOSupfS 11 HA 44 l  !

45 UA 3c I

w M.E. -, :ES:=i- ,eN m is:

7 t101O!o!@lcl@l 6 i tt 1 13 na gg i

8EaSONNE. .mbniES w veer  ::.uminmeN -- 1 i ,,i 5!0106o!@l 7 i t1 t:

na i

^

t , n i. li s.

'JP. ' "iSs'#0T'"" @

A 7812296Fa4  ;

a i *; ,;

SL E L:Ot *v g ,.- .---c .~. . ,

R,,,N e .

I: ;i l.S$ ah

'T i-v l:ES: '

I!s .If i ' l t ' I f 1 -

4 9 j . ,e 3 -i fi

., O.*n-g-- ., .- +-.

- #* ,,n ./a~~~~~~'#*

' ~~~ ~~ '~~'Y~~'--

NAME ** *ac8 A AEm 8-CN E-

~ _. .__ ..

1 lIR 78-Oh2 0-^a Public Power District Fort Calhoun Station Unit ilo. 1-Docket No. 05000285

i. Attachment No. 1 Safet1 Analysis The Fort Calhoun Station Unit No.1 safety syste= is so designed that no l

single inoperable channel can prevent the perfomance of a safety function if j required. During the ti=e in which PC-105B was inoperable, Plos, the redund-ant channel was operable.

I The function of the shutdown cooling interlock is to provide automatic isolation of the shutdevn cooling isolation valves HCV-3kT and ECV-3h8 to protect the safety injection piping in the event the reactor coolant loop

( pressure' exceeds 250 psia while on the shutdown ecoling decay heat renoval syste=. Operator action and the auto =atic operation of P105 intericek pro-vided adequate protection'of the piping during the ti=e PC-1053 was inoperable.

It should be noted that .HCV-3kT'and ECV-3h8 are locked closed during power operation. Opening these valves when reactor coolant system pressure is greater than 250 psia is prevented bf:

1. Ad=inistrative control of key operated control switch,

2. P-105 pressure interlock, and ,

3 PC-1053 pressure switch interlock.

PC-1053 was incapable cf perfor-4ng its interlock function as a result of this incident. Pressure channel 113/115 nov perfor=s this interlock function 4

in conforance with the design package.

s

". // / r l bl i

I

.-,nn, +-, . , - - - , - . ~ . - - ~ = - - , ,, -

.,.v,,, - - - , - , - . . , .-, , , , , ,

~IF. 78-Ch2 C=aha Public Pcver District Fort Calhoun Station Uni,:Ic. 1 tocket UO. 050002B5

. Attach =ent No. 2 Corrective Action to P-event Rececu-rence Adherence to the recently revised Station Modi'.ication Control Procedure should prevent reoccurrence of this type incident.

,,e' W

(

d I

i

7.2?. 7S-ch2 C=aha Public Power Distric:

Fort Calhoun Station Unit No. 1 Docket No. 03000233

• Attachnent No. 3 Failure Dsts This is the first installation e - -epor.able at the Fort Calhoun Statics Unit no. 1.

i h0 k

1