ML19269E288

LER 79-017/03L-0 on 790525:both Source Range Channels Lost for Three Menutes When All Power Range Channel Control Power Fuses Were Pulled.Caused by Procedure Error.Fuses Reinstalled & Procedure Changed

ML19269E288
Person / Time
Site:	Prairie Island
Issue date:	06/22/1979
From:	Hunstad A NORTHERN STATES POWER CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19269E284	List: ML19269E283 ML19269E288
References
LER-79-017-03L, LER-79-17-3L, NUDOCS 7906270165
Download: ML19269E288 (1)

Text

(7-77)

LICENSEE EVENT REPORT CONTROL BLOCK: l 1

l l l l l

__6 lh (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATIONI l0l1l M!

NLICENSEE l P l CODE I l N l 141 l@l 0 l 0 l- ! OLICENSE l 0 lNUMBER 0 l 0 l 0l -l0 l 025l@l4 2b l1LICENSE l1 l 1TYPE l 1JOl@lbl LAI V l@

7 8 9 15 CON'T "7

lalij ,"{gc l6CL l@l610 l 5 l 0DOCKET 0 l0 l 2 [ 8 l 268@l690 l 5EVENT l 2 OATE l5 l 7 l 914 l@l0 l 6REPORTl ?lDATE 2l7l9 @

7 8 NUMBER 75 .' u EVENT DESCRIPTION AND PROBABLE CONSEQUENCES h l o 121 l During refueling shutdown, both NIS sourco range channels were lost for about threej o 3 l minutes when all power range channel control power fuses were pulled for installati9n oi 4 l work f or a Design Change. (When the fuses were pulled all power range ghannels j o 3 tripped high simulating power above the P10 permissive and blocking source range j o e I high voltage) No effect on public health and safety. Not repetitive (a once- )

o 7 l only procedure). l o 8 l __]

7 8 9 "'

SYSTEM CAUSE CAUSE COVP. VALVE CODE CODE SU8 CODE COvPONET CODE SUBCCDE SUBCODE O 9 lIl A l@ {Q lZ @ l Il NlS j't lR l U l@ l I g ]@

7 8 9 to 11 12 13 IN 19 .'O

_ SEQUENTI AL OCCU R R F NCE REPORT HE\ h ^

LER RO EVENT YEAR REPORT NO CODE TYPE NO

@ RE

_ 21 l7l9 22 l_l 2J l0 1l 7 24 26 y

21 l0l3 28 29 lLl JO g

31 gE' T KEN ACT CP oN PL NT YET HOURS 22 SB IT D FOR S 8. SLPPllE YAN F 5 ?t f' 33 X

lgl34 l@G lZ lg J5 l%Zl@

l 0l 0l 0l 31 l

43 l Nlg 41 42 g lN [g l Zl 9l 9l 9lg 43 44 4 CAUSE DESCRIPTION AND CORRE^TIVE ACTIONS 3 o j Procedure error. Fuses were quickly reinstalled. Procedure was changed to call  ;

i ;i; [ for pulling power range fuses one at a time for the installation work. 1 I i 171 l l It 131 l l 1 4 1 _i i a 9 S A $  % POWER OTHER STATUS is H DISCOV EHY DEsCRIP fiCN i ,, {g 0[ 0l 0lgl NA l g0peratorobservation J A TIVf TY CON TEl% T e REL6ASED OF RELE ASE AMOUNT OF ACTIVITY LOC ATf 0N OF HE L E A?L I i c LZ_J @ 10LZJ@l11 NA l l NA l 1 a 9 44 45 PF R',0NNE L FxPosuHE5 NUURE R TYPE DESCHIPTIOrJ -

NA i 7 l 0 l 0 l0 l@l Z l@l J PERSONNE L INJul ES NUYMER DESJqlPTION 0 l 0 l@[ NA i . l 0. J l 8 9 *1 12 A @

t O' S OF OH DAMAGE TQ f ALill TY TYPE DESC'HPflON i o LZj@l NA l 1 8 9 10 <

PURt iCI T Y gg g ,: , ,g3 D C.L R!PilON 2 o

,, 9 W

1%UE D@l m

NA l

,,s .-.

llllll1l ll l;*

NAVE Or PREPARE R

. . Hunstad pggg g . W4%MJ 3 7906270rg r f