ML17338B328

LER 79-023/03L-0:on 790823,source Range Monitor Calibr Supplied Rod Block Trip at 1.03E5,exceeding Tech Specs Limit.Caused by Drift & Temp Dependency in Source Range Monitor.Defective Component Not Yet Identified

ML17338B328
Person / Time
Site:	Dresden
Issue date:	09/17/1979
From:	Korchynsky M COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML17174A032	List: ML17338B328
References
LER-79-023-03L-01, LER-79-23-3L-1, NUDOCS 7909280429
Download: ML17338B328 (2)

Text

~

I>> FOBIVI 366 U. S. NUCLEAR REGULATORY COMMISSION CONTROL BLOCK:

",ENSEE EVENT REPORT Qi 1

(PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

I 6

[0D1]

8 9 1 L 0 LICENSEE CODE E S 3 14 QE 15 0 0 0 0 0 LICENSC NUMGEB 0 0 25 Qs 2G 4 1 1 1 LICENSE TYPE 1

30 Q4~Q 57 CAT 58 CON'T La~i '"oRT~LQR 0 3 0 0 0 2 PP 9 Qio 69 S 2 EVENT DATE 3 7 9 74 Qso 75 9 2 1 REPORT DATE 7 9 80 Qs 7 8 60 61 DOCKET NUMBER GG EVENT DESCRIPTION AND PROBABLE CONSEQUENCES Q10 Phile performing weekly surveillance DES 700-3 (Source Range Monitor Calibration) on two separate occasions, SRM /I2 1 supp 1 ied required Rod Block Trip at 1 . 03E5 f ~3 remaining SHN channels were operable and would have rovided re uired Rod Block.

Event has occurred before on Dresden 3 RO 879-15-03L-0 80 SYSTEI'I CAUSE CAUSE COMP. VALVE CODE CODE SUGCODE COMPONENT CODE SUGCODE SUGCODE E~g 9

S 10 Qii 11 E Qi2 ~GQE3 12 13 2 N S 'I E 0 18 Qi4 ~QEE 19

~2Q 20 SEOUENTIAL OCCURRENCE REPORT REVISION Gi LERIRO REPORT ACTION FUTURE EVFNT YEAR

~79 21 22 EFFECT

~

23 SHUTDOWN

~02 24 REPORT NO.

3 2G

~~

27 ATTACHMENT

~03 28 CODE 29 NPRDR TYPE

~L 30 31 PRIME CODIP.

~0 NO.

32 COMPONENT TAKEN ACTION

~ap>>~Zp>>

33 ., 34 ON PLANT

~ZQEo 35 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS 27 METHOD

~ZQET 36 37 O

HOURS Q22 O O O 40 SUGMITTED 41 N Q23

'2 FORM SUG.

~YQ24 SUPPLIER

~~E 43 44 MANUFACTURER 0 O S OQEO 47 The out ut: of the SRH //21 low leve demonstrat:ed a temperature dependency. The exact corn onent involved has not et been loca A supplemental report will be submitt:ed when the cause is identified. The SRM's are I~3 checked week 1 y .

7 8 9 80 FACIUTY STATUS  % POWER OTIIEB STATUS 'Q METHOD OF DISCOVERY DISCOVERY DESCRIPTION Q32 s E Qs ~07 SJQ>>

12 NII .

44

~BQET 45 46 Surveillance Tescinz 80 7 8 9 10 13 ACTIVITY CONTENT RELEASED OF RELEASE AMOUNTOF ACTIVITY LOCATION OF RELEASE L~J Q33 z Q34 NA 7 8 9 10 11 44 45 80 PERSONNEL EXPOSURES NUMGER TYPE DESCRIPTION

~>> ~oo 7 8 9 o Qsi~zQEE 11 12 13 80 PFBSONNEL INJUIIIES NUMGEB DESCRIPTION 41

~00 o Q,.

80 9 11 12 LOSS OF OB DAMAGE To FACILITY TYPE

~ZQ42 OL'SCRIPTION qgggg80 i 7 8 9 10 80 ISSUED

~N PUBLICITY Q44 DESCRIPTION ~ NRC USE ONLY E IO 80 ~ ER 0

NAME OF PREPARER H. Korch nsk PHONE: D 43

+CO t,4 n