05000338/LER-1980-103-03, /03L-0:on 801113,containment Matl Seismic Recorder ER-002 Failed Periodic Test PT-39.5.Caused by Electronic Fault in Field Sending Unit.Total Component Replaced

/03L-0:on 801113,containment Matl Seismic Recorder ER-002 Failed Periodic Test PT-39.5.Caused by Electronic Fault in Field Sending Unit.Total Component Replaced

ML19340D594
Person / Time
Site:	North Anna
Issue date:	12/22/1980
From:	Cartwright W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19340D590	List: 05000338/LER-1980-103, Forwards LER 80-103/03L-0 05000338/LER-1980-103-03, /03L-0:on 801113,containment Matl Seismic Recorder ER-002 Failed Periodic Test PT-39.5.Caused by Electronic Fault in Field Sending Unit.Total Component Replaced
References
LER-80-103-03L, LER-80-103-3L, NUDOCS 8012310330
Download: ML19340D594 (2)

LER-1980-103, /03L-0:on 801113,containment Matl Seismic Recorder ER-002 Failed Periodic Test PT-39.5.Caused by Electronic Fault in Field Sending Unit.Total Component Replaced

Event date:
Report date:
3381980103R03 - NRC Website

text

.

j 1 O j

U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT l

\\

CONTROL BLOCK / / / / / / / (1)

(PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

)

/0/1/

/V/A/N/A/S/1/ (2)

/0/0/-/0/0/0/0/0/-/0/0/ (3)

/4/1/1/1/1 (4)

/ / / (5) 1 LICENSEE CODE LICENSE NUMBER LICENSE TYPE CAT

/0/U L/L (6)

/0/5/0/0/0/3/3/8/ (7)

/1/1/1/3/8/0/ (8) /1/ 2/ 2/ 2/ 8/ 0/ (9)

DOCKET hW1BER EVENT DATE REPORT DATE i

EVENT DESCRIPTION AND PROBABLE CONSEQUENCES (10)

/0/2/

/

On November 7, 1980 while in Mode 1, the containment mat seismic recorder ER-

/

+

/0/3/

/

002 failed to meet the acceptance criteria of the periodic test PT-39.5 and

/

/0/4/

/

was declared inoperable.

Since other portions of the seismic monitoring system /

/0/5/

/

remain operable, the health and safety of the public are not affected. This

/

.) /0/6/

/

item is reportable pursuant to T.S. 6.9.2.c (Special Report).

/

/0/7/

/.

/

/0/8/

/

/

SYSTEM

CAUSE

CAUSE COMP.

VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE

/0/9/

/I/E/ (11) [E( (12) /G/ (13) /I/N/S/T/R/U/ (14) /E/ (15)

LZ/ (16)

SEQUENTIAL OCCURRENCE REPORT REVISION LER/R0 EVENT YEAR REPORT NO.

CODE TYPE NO.

(17) REPORT NUMBER

/8/0/

/-/ /1/0/3/

/\\/

/0/3/

/L/

/-[

/0/

j ACTION FUTURE EFFECT SHUTDOWN ATTACHMENT NPRD-4 PRIME COMP. COMPONENT TAKEN ACTION ON PLANT METHOD HOURS SUBMITTED FORM SUB. SUPPLIER MANUFACTURER

/Z/ (18) /C/ (19) /Z/ (20) /Z/ (21) /0/0/0/0/ (22) LY/ (23) /N/ (24) LA/, (25) /E/2/5/9/(26) 2 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS (27)

/1/0/

/

The field sending unit developed an electronic fault when the circuit was

/

/1/1/

/

tested. Since this unit is located in an area of high radiation during oper- /

l

/1/2/

/

ation, the total component will be replaced during the planned refueling outage /

/1/3/

/

commencing in early 1981.

/

/1/4/

/

/

FACILITY METHOD OF STATUS

% POWER OTHER STATUS DISCOVERY DISCOVERY DESCRIPTION (32)

/1/5/

/E[ (28)

/0/9/2/ (29) /

NA

/ (30) /B/ (31) /

Periodic Test

/

ACTIVITY CONTENT RELEASED OF RELEASE AMOUNT OF ACTIVITY (35)

LOCATION OF RELEASE (36)

/1/6/

/Z/ (33)

/Z/ (34) /

NA

/

/

NA

/

PERSONNEL EXPOSURES NUMBER TYPE DESCRIPTION (39)

/1/7/ /0/0/0/ (37) /ZL (38) /

NA

@[""

]' '](_.

/

1 PERSONNEL INJURIES NUMBER DESCRIPTION (41) o

/1/8/ /0/0/0/ (40) /

NA

/

LOSS OF OR DAMAGE TO FACILITY (43)

TYPE

DESCRIPTION

/1/9/

/Z/ (42) /

NA

/-

PUBLICITY ISSUED DESCRIPTION (45)

NRC USE ONLY

/2/0/

/N/ (44) /

NA

/////////////

NAME OF PREPARER W. R. CARTWRIGHT PHONE (703) 894-5151 8 01281 sso

Virginia Electric and Power Company North Anna Power Station, Unit 1 Attachment: Page 1 of 1 Docher No. 50-338 Repott No. LER 80-103/03L-0 i

Description of Event

The containment mat triaxial response-spectrum recorders were tested in accordance with the periodic test PT 39.5.

When the test button was depressed to initiate a circuitry check, the unit operated satisfactorily. However when the test signal was removed, two alarm channels did not clear. Subsequent testing of the circuitry cards confirmed that the fault was in the sending unit.

Probable Consequences of Occurrence The affected recorder provides an alarm indication in the main control room and also provides a record of seismic acceleration. Since the unit incorporates a trixial monitoring capability over a series of frequency ranges, the consequences of a failure of two specific frequency signals (2Hz and 3.2Hz) are negligible. The normal measurement range extends from 2 to 25.4 Hz with 12 separate channels.

Cause of Event

An investigation into the failure of the alarm circuits to clear revealed that the field mounted unit was the source of the alarm. The manufacturer was contacted to assist in an analysis of the fault. A capacitor failure was determined to be the most likely cause.

Immediate Corrective Action

Since the field unit is installed in an area of high radiation during reactor operation, no immediate corrective action was taken to repair the unit. The control room operators and shift supervisors were made aware of the fault.

Scheduled Corrective Action A maintenance request was submitted to replace the total component with a shop calibrated unit. This action will be taken during the January, 1981 refueling outage.

Actions Taken to Prevent Reccurrence This failure is considered an isolated event.-

Therefore, no actions, to prevent recurrence are deemed necessary.

Generic Implications r

There are no generic implications associated with this event.

+