05000281/LER-1975-005, Updated LER 75-05/010:on 750225,radial Trip of Max 2.5% Existed.Caused by Prolonged Recovery of Rod F-2.Control Room Alarm Did Not Function Due to Defective Circuit Card. Card Replaced & Staff Cautioned

Updated LER 75-05/010:on 750225,radial Trip of Max 2.5% Existed.Caused by Prolonged Recovery of Rod F-2.Control Room Alarm Did Not Function Due to Defective Circuit Card. Card Replaced & Staff Cautioned

ML20086Q742
Person / Time
Site:	Surry
Issue date:	04/08/1975
From:	Baucom T, Stallings C VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	Moseley N NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20086Q745	List: 05000281/LER-1975-005, Updated LER 75-05/010:on 750225,radial Trip of Max 2.5% Existed.Caused by Prolonged Recovery of Rod F-2.Control Room Alarm Did Not Function Due to Defective Circuit Card. Card Replaced & Staff Cautioned ML20086Q767
References
446-S, LER-75-05-010, LER-75-5-10, NUDOCS 8402280117
Download: ML20086Q742 (2)

LER-2075-005, Updated LER 75-05/010:on 750225,radial Trip of Max 2.5% Existed.Caused by Prolonged Recovery of Rod F-2.Control Room Alarm Did Not Function Due to Defective Circuit Card. Card Replaced & Staff Cautioned

Event date:
Report date:
2812075005R00 - NRC Website

text

.

LICENSEE EVENT REPORT updatcd Report Previous Report Dated 022575 O# *

• CONTROL ULOCK s

! l l l l l (PLEASE PRINT ANh n L INFORMATION) 1 6 NA ( (CENSE NUMO!n i TV (

LE Iv l^ l s I el si 21 I1bolo I-I ol of ol olo I-Io.1 o'l I 41 i I ili lo I lo li I 7 09 14 23 20 30 31 32 CA1(C00f ty fu DOCKET NUMRin (VENT DAff $4E8'ont DATC

@COtri l p l 0 l 7 o 57 bo d09 W 60 l0 l 5 l 0 l-l 0 l 2l 8l 1l 61 UU

[0 l 2 l 2 l 5 l 7 l 5l 69 74 l0 l4 l0 l8 l 7 l 5l 75 00 EVINT DESCntPilON i

EB l Durinn 100 per cent power operation a check of the outputs of the excore detectors l 7 UU ca

@[ l revealed that a radial tilt of a maximum of 2.5 per cent existed. This tilt had been [

7 oo ao E[ l generated earlier in the day be a dropped control rod and the operations associated l 7 oD co

, @ l with its recovery. The tilt resulted from the prolonged recovery of the rod (F-2) l 7 oo go gg [ which built in a radial Xenon distribution. A0-S2-75-05 l 7 uo ,,,,,,, eo SYSitM cAust CoWONTNT COMPONtPa rout Cout COMPONENT CODE sursu n MAfJUI AClur{H VIOLATON BE l RlC l W 7 UU 10 11 lIl Nl Sl TlR lU l 12 17 U43 44 lW l 1l 2l0 l 47

[j 48 CAUSE DESCn!PTION DE l A control room alarm, based on excore detcetors, h'ortaally alerts the operator in the l 7 o9 oo

@ l cvent the core radial distribution tilts 2 per cent or more to any upper or lower l 7 09 80 c

DE b undrant. This alarm did not function due to a circuit card which was defective.

7 nU

]un

's~17tN s Pomn otstn stArus Es'EEv" trey" oiscovtar otsenc10N 7 0 W l 1l0 l0 l l N/A 10 12 13 44 l ]4S l 46 N/A 80 l

ACIMTY CONT E N T OCLEAS!D AMOUNT OF ACIM1Y LoCA10N of AELEASE ll l A_j OF 5;ttf A$f l d10 N/A l l N/A l 7 0 0 11 44 4b 00 pen 3ONNEL EXPOSURES NUM0tn itPE DISCfhPT OtJ gg l 0l0 l 0 l [ 4J l N/A l 7 OD 11 12 13 60 PERSONNEL INJun:ES NUMD(n OCSCH:PTON

@ l0l0l0l11 12 7 89 l N/A l 00 Of FSITt CONSEQUENCES hl N/A 7 00 80 l

LOSS On OAMAGE TO FACILITY

• TYPF Dtf.CFtP10N .

.7 35 o9 d l N/A l ,

to so PUBLICITY 8402280117 750408 Ql N/A 7 00 hDRADOCK 05000281 PDR l.

., 60 ADDITIONAL FACTORS Ql lThe failed card was replaced and the operations staff cautioned to monitor the ,xcore l 7 89 ao g ldctector-indicated. tilt subsequent to dropped rod occurrences. g 7 00 8o  ;

NAME: Tyndall L. Baucom ONE(804) 771-3748 .

l GPO 889 467 I

~

O O END s

. .s..,

7 s.

Vtuonn:A ELEcrn:C AND POWEH COMI'ANY *[ [.#

.z

. , h,'i nionwonn.vanoix A unco

• t -. u; .

,(*c . o];;:y,'.7 April 14, 1975 -

kT . .

N'; . . .- -

Mr. Noman C. lioneley, Director Scrial No. 446-S Office of Incpection and rnforcement- P0&M/JTDac1w United States I;uclear Regulatory Commission Ecgion II - Suito 818 Docket No. 50-281 230 Peachtree Street, Nortiniest License No. DPR-37 Atlanta, Georgia 30303

Dear Mr. Moseley:

Attached for your information are forty (40) copies of supplementary information for Abnora l occurrence Report No. A0-S2-75-05.

Very truly yours; b.Nf.8hk'y '

O. M. Stallings ,

Vice Precident-Pouer Supply l nnd Production Operations .

Fuelocures 40 copies of A0-S2-75-05 .

cc: Mr. K. R. Coller b

, . ,