05000338/LER-1980-104-99, /99T-0:on 801223,environ Telemetry Channel 6 for Air Temp Found Out of Tolerance High During Calibr.Caused by Printed Circuit Card Failure in Transmitter Multiplexer.Card Removed & Sent to Manufacturer for Repairs

/99T-0:on 801223,environ Telemetry Channel 6 for Air Temp Found Out of Tolerance High During Calibr.Caused by Printed Circuit Card Failure in Transmitter Multiplexer.Card Removed & Sent to Manufacturer for Repairs

ML19340E179
Person / Time
Site:	North Anna
Issue date:	01/02/1981
From:	Cartwright W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19340E161	List: 05000338/LER-1980-104, Forwards LER 80-104/99T-0 05000338/LER-1980-104-99, /99T-0:on 801223,environ Telemetry Channel 6 for Air Temp Found Out of Tolerance High During Calibr.Caused by Printed Circuit Card Failure in Transmitter Multiplexer.Card Removed & Sent to Manufacturer for Repairs
References
LER-80-104-99T, NUDOCS 8101060599
Download: ML19340E179 (2)

LER-1980-104, /99T-0:on 801223,environ Telemetry Channel 6 for Air Temp Found Out of Tolerance High During Calibr.Caused by Printed Circuit Card Failure in Transmitter Multiplexer.Card Removed & Sent to Manufacturer for Repairs

Event date:
Report date:
3381980104R99 - NRC Website

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LICENSEE EVENT REPORT CONTROL BLOCK / / / / / / / (1)

(PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

C/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)

LICENSEE CODE LICENSE NUMBER LICENSE TYPE CAT

/0/1/

[L[ (6)

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

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

DOCKET NUMBER EVENT DATE REPORT DATE EVENT DESCRIPTION AND PROBABLE CONSEQUENCES (10)

/0/2/

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On December 16, 1980, environmental telemetry channel 6 for air temperature

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A T was declared inoperable after being four.d out of tolerance high during

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calibration. This condition existed for more than 7 days and is therefore re- /

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portable pursuant to Specification 6.9.2 in accordance with the Action State- /

j

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ment of T.S. 3.3.3.4.

Since redundant air temperature delta T indication is j

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available locally and the stability class can be determined by alternate means,/

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the health and safety of the general public are not affected/

SYSTEM

CAUSE

CAUSE COMP.

VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE

/0/9/

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

/_Z/ (16)

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

CODE TYPE NO.

(17) REPORT NUMBER

/8/0/

/-[ /1/0/4/

/\\/

/9/9/

/T/

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[0/

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

'X/ (18) [D[ (19) /Z/ (20) /Z/ (21) /0/0/0/0/ (22) /Y/ (23) /N/ (24) [L[ (25) /R/2/4/5/(26)

CAUSE DESCRIPTION AND CORRECTIVE ACTIONS (27)

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The channel inaccuracy has been attributed to a failure of a printed circuit

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card (64TMX1A) in the transmitter multiplexer. The card was removed and deliv-/

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ered to the manufacturer for repair. Since there were no spare cards available/

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the turnaround time has exceeded 7 days. The repaired card or new card will be/

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installed and the channel recalibrated upon receipt from the manufacturer.

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FACILITY METHOD OF STATUS

% POWER OTHER STATUS DISCOVERY DISCOVERY DESCRIPTION (32)

/1/5/

[E/ (28)

/0/6/5/ (29) /

NA

/ (30) [B[ (31) /

Surveillance Test

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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) [Z[ (38) /

NA

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PERSONNEL INJURIES oe o

NUMBER DESCRIPTION (41)

O g-

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

NA oo o

a

/

LOSS OF OR DAMAGE TO FACILITY

)

TYPE

DESCRIPTION

/1/9/

[Z[ (42) /

NA

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1 i

}

PUBLICITY ISSUED DESCRIPTION (45)

NRC USE ONLY

/2/0/

LNf_(44) /

NA

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NAME OF PREPARER W. R. CARTWRIGHT PHONE (703) 894-5151 8101060 f

i O

Virginia Electric and Power Company North Anna Power Station, Unit 1

Attachment:

Page 1 of 1 Docket No. 50-338 Report No. LER 80-104/99T-0

Description of Event

On December 16, 1980, during periodic calibration of the meteorological monitoring system, the air temeperature delta T telementry channel failed to meet the required accuracies and was declared inoperable. For the worst case, the channel read 11.2 F high. This event is contrary to T.S. 3.3.3.4 and, since existing for more than 7 days, reportable pursuant to T.S. 6.9.2.

Probable Consequences of Occurrence The air temperature delta T instrumentation senses vertical temperature gradients between 10 meters and 49 meters above ground level for determining stability class. This data is used to develop atmospheric diffusion parameters for estimating potential radiation doses to the public resulting from actual, routine or abnormal releases of radioactive materials to the atmosphere. Because operable local indication of air temperature delta T is available and alternate means of determining stability class are available, the health and safety of the general public are not affected by this event.

r-'

Cause of Event

V)

The inaccuracy in the channel was caused by the failure of a printed circuit card (64TMX1A) in the transmitter multiplexer.

Immediate Corrective Action

The failed card was removed and delivered to the manufacturer for necessary repairs. Due to the nature of the card, ready spares were unavailable and thus the turnaround time has exceeded 7 days.

Scheduled Corrective Action When received from the manufacturer, the repaired card or a new replacement card will be installed and the channel recalibrated to restore operability. The card is expected from the manufacturer by l

January 7,1981.

Actions Taken to Prevent Reccurrence No futher actions are required.

Generic Implications There are no generic implications associated with this occurrence.

ON