05000339/LER-1980-009-03, /03L-0:on 800522,power Supply for Main Steam Pressure Protection Channel III Failed High,Causing Steam Line Pressure Mismatch.Caused by Failed Card in Power Supply.Card Was Replaced & Calibr

/03L-0:on 800522,power Supply for Main Steam Pressure Protection Channel III Failed High,Causing Steam Line Pressure Mismatch.Caused by Failed Card in Power Supply.Card Was Replaced & Calibr

ML19318A644
Person / Time
Site:	North Anna
Issue date:	06/18/1980
From:	Cartwright W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19318A641	List: 05000339/LER-1980-009, Forwards LER 80-009/03L-0 05000339/LER-1980-009-03, /03L-0:on 800522,power Supply for Main Steam Pressure Protection Channel III Failed High,Causing Steam Line Pressure Mismatch.Caused by Failed Card in Power Supply.Card Was Replaced & Calibr
References
LER-80-009-03L-02, LER-80-9-3L-2, NUDOCS 8006230551
Download: ML19318A644 (2)

LER-1980-009, /03L-0:on 800522,power Supply for Main Steam Pressure Protection Channel III Failed High,Causing Steam Line Pressure Mismatch.Caused by Failed Card in Power Supply.Card Was Replaced & Calibr

Event date:
Report date:
3391980009R03 - NRC Website

text

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U.S. NUCLEAR REGULATORY COMMISSION

/~g LICENSEE EVENT REPORT

- V CONTROL BLOCK / / / / / / / (1)

(PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

/0/1/

/V/A/N/A/S/2/ (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/

REP 0

/L/ (6)

/0/5/0/0/0/3/3/9/

(7)

/0/5/2/2/8/0/

(8)

/o/6 /1/3 /8 /o (9)

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

!/0/2/

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On May 22, 1980, with the unit in Hot Standby conditions, the power supply for /

/0/3/'

/

main steam pressure Protection Channel III failed high causing "B" steam line- /

4

/0/4/

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pressure input to the solid state protection system to indicate a steam line

/

l/0/5/

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pressure mismatch. Since the affected channel was placed in the tripped con- /

/0/6/

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dition and both redundant channels were available to initiate S1 on a 1/2 logic /

/0/7/

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if required, the health and safety of the general public were not affected.

/

(fp/8/

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Reportable pursuant to T.S. 6.9.1.9.b.

/

SYSTEM

CAUSE

CAUSE COMP.

VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE

/0/9/

/I/B/'(11)

/E/ (12)

/G/ (13) /I/N/S/T/R/U/ (14)

LP/ (15)

[Z/ (16)

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

CODE TYPE NO.

(17)

REPORT NUMBER

/8/0/

/-/ /0/0/9/

/\\/

/0/3/

/L/

/-/

[0/

ACTION FUTURE EFFECT SHUTDOWN ATTACHMENT NPRD-4 PRIME COMP.

COMPONENT TAKEN ACTION ON PLANT METHOD HOURS SUBMITTED FORM SUB. SUPPLIER MANUFACTURER

/C/ (18)

/Z/ (19)

/Z/ (20) /Z/ (21) /0/0/0/0/ (22) [Y/ (23)

/N/ (24) /N/ (25) /W/1/2/0/ (26)

CAUSE DESCRIPTION AND CORRECTIVE ACTIONS (27)

/1/0/

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A card in the power supply failed causing a high steam line pressure signal

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/1/1/

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input to the ESFAS.

This caused one channel out of a 2/3 logic system to

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/1/2/

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annunciate on differenital pressure SI.

The card was replaced and calibrated /

/1/3/

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thus restoring the protection channel to operable status.

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/1/4/

/

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FACILITY HETHOD OF STATUS

% POWER OTHER STATUS

/ ( 0) DISCOVERY DISCOVERY DESCRIPTION (32)

/1/5/

/D/ (28)

/0/0/0/ (29) /

NA

/A/ (31)

/ OPERATOR OBSERVATION /

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)

L/1/7/ /0/0/0/ (37) /Z/ (38)

/

NA

/

PERSONNEL INJURIES NUMBER DESCRIPTION (41)

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

NA

/

LOSS OF OR DAMAGE TO FACILITY (43) l TYPE

DESCRIPTION

j/1/9/

'/Z/ (42)

/

NA

/

l PUBLICITY l

ISSUED DESCRIPTION (45)

NRC USE ONLY E.006230 $il5 l/2/0/

/N/ (44) /

NA

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

Virginia Electric and Power Company North Anna Power Station, Unit #2

Attachment:

Page 1 of I Docket No. 50-339 Report No. LER 80-009/03L-0

Description of Event

on May 22, 1980, with the unit in Hot Standby conditions the power supply for main steam pressure protection Channel III failed high trip-ping one channel of the solid state protectica system for a main steam line differential pressure S1.

Two out of three logic is required to actuate a safety injection in this case and this channel was placed in -

the tripped condition within one hour of observing condition on alarm board. This resulted in a loss of one out of three channels of steam line pressure indication which is contrary to T.S. 3.3.2.1.

Reportable pursuant to 6.9.1.9.b.

Probable Consequences of Occurrence The power supply that failed caused one channel to trip out of

- three possible channels. That channel was placed in the trip position which changed the logic from 2/3 to 1/2 channels for initiation of a safety injection which is a more conservative plant condition.

The unit was also shut down and the health and safety of the general public were not affected by this event. There are no generic implications associ-ated with this occurrence.

Cause of Event

The cause for the steam line pressure mismatch on Channel III was a defective non-isolable loop power supply card.

Immediate Corrective Action

The channel was placed in trip within one hour of indication via the alarm panel af ter the malfunction.

An Emergency Maintenance Request was initiated and the faulty card was diagnosed, replaced and calibrated the same day the fault occurred.

Scheduled Corrective Action No scheduled corrective action is required.

Actions Taken to Prevent Recurrence No further action required.

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