05000338/LER-1980-059-03, /03L-0:on 800623,during Periodic Test on Low Head Safety Injection Sys,Recirculation Valve Failed to Reopen on Demand Resulting in Blocked Recirculation Flow Path.Caused by Defective Electrical Switch.Locking Ring Replaced

/03L-0:on 800623,during Periodic Test on Low Head Safety Injection Sys,Recirculation Valve Failed to Reopen on Demand Resulting in Blocked Recirculation Flow Path.Caused by Defective Electrical Switch.Locking Ring Replaced

ML19330A961
Person / Time
Site:	North Anna
Issue date:	07/22/1980
From:	Cartwright W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19330A960	List: 05000338/LER-1980-059, Forwards LER 80-059/03L-0 05000338/LER-1980-059-03, /03L-0:on 800623,during Periodic Test on Low Head Safety Injection Sys,Recirculation Valve Failed to Reopen on Demand Resulting in Blocked Recirculation Flow Path.Caused by Defective Electrical Switch.Locking Ring Replaced
References
LER-80-059-03L, LER-80-59-3L, NUDOCS 8007290843
Download: ML19330A961 (2)

LER-1980-059, /03L-0:on 800623,during Periodic Test on Low Head Safety Injection Sys,Recirculation Valve Failed to Reopen on Demand Resulting in Blocked Recirculation Flow Path.Caused by Defective Electrical Switch.Locking Ring Replaced

Event date:
Report date:
3381980059R03 - NRC Website

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D U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT

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

(PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

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/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)

/0/6/2/3/8/0/ (8) /o/7/2/2/8/o/ (9)

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

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While performing a periodic test on the LHSI system, a recirculation valve

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failed to reopen urca demand, resulting in a blocked recirculation flow path

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from the "B" LHSI pump to the RWST.

In the event of a SI signal, the pump is /

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started automatically, and it would be deadheaded unless MOV-1863B was cpened /

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establishing a flow patu to the charging pumps, or the pressure in the RCS

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fell below 200 psig. Since a redundant LHSI system was available, the health /

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and safety of the public were not affected.

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SYSTEM

CAUSE

CAUSE COMP.

VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE

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/S/F/ (11) /E/ (12) /A/ (13) /I/N/S/T/R/U/ (14) /S/ (15)

/_Z/ (16)

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

CODE TYPE NO.

(17) REPORT NUMBER

/8/0/

/-/ /0/5/9/

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/L/

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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 MANUFACTURER

/B/ (18) /Z/ (19) /Z/ (20) /Z/ (21) /0/0/0/0/ (22) /_Y/ (23) /N/ (24) /X/ (25) /C/7/7/6/ (26 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS (27)

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The valve did not open because of a defective electrical switch in the control /

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room. A locking ring which holds the switch assembly together had worked

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loose preventing the necessary electrical connection. The locking ring was

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replaced and the switch was tested and observed to operate the valve satis-

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factorily.

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FACILITY METHOD OF STATUS

% POWER OTHER STATUS DISCO N DESCRIPTION (32)

/ (30p SCO M

/1/5/

/E/ (28)

/1/0/0/ (29) /

NA

/B/ (31)

/ ROUTINE PERIODIC TEST /

ACTIVITY CONTENT RELEASED OF RELEASE AMOUNT OF ACTIVITY (35)

LOCATION OF RELEASE (36)

/1/6/

/Z/ (33)

/Z/ (34) /

NA

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/

NA

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PERSONNEL EXPOSURES NUMBER TYPE DESCRIPTION (39)

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

NA

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PERSONNEL INJURIES NUMBER DESCRIPTION (41)

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NA

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LOSS OF OR DAMAGE TO FACILITY 3)

TYPE

DESCRIPTION

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NA

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PUBLICITY ISSUED DESCRIPTION (45)

NRC USE ONLY

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/N/ (44) /

NA

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NAME OF PREP R

W. R. CARTWRIGHT PHONE (703) 894-5151 800 72g0

n Virginia Electric and Power Company North Anna Power Station, Unit #1 Attachment: Page 1 of 1 Docket No. 50-338 Attachment to LER 80-059

Description of Event

On June 23, 1980 while operating in Mode 1 at 100% power, the Operations Department was conducting a periodic test (1-PT-57.2) on the Low Head Safety Injection System. The purpose of the test is to cycle two valves, and measure their stroke time. The valve MOV-1885D is closed in order to perform the test. Under normal operating conditions MOV-1885D is open so that there is a minimum flow bypass line going from the Low Head Safety injection pump "B" back to the Refueling Water Storage Tank (the tank from which the pump takes its suction). This valve, MOV-1885D, failed to reopen upon demand. The applicable Technical Specification is 3.5.2., and the event is reportable pursuant to 6.9.1.9.b.

Probable Consequences of Event If there had been a safety injection signal at this time, the "B"

pump would have started automatically, and in order to prevent the pump from becoming deadheaded, MOV-1863B could have been opened so as to establish a flow path to the charging pumps.

If the RCS pressure were to drop below 200 psig, the pump would have a flow path into the Reactor Coolant System. Since a redundant Low Head Safety Injection System was available for emergency core cooling, and the system affected by MOV-1885D could have been retained in a functional condition, the health and safety of the public were not affected.

Cause of Event

The valve (MOV-1885D) did not open because cf a defective electrical switch in the control room. A locking ring which holds the switch assembly together had come loose preventing the necessary electrical connection from being made.

Immediate Corrective Action

The locking ring was replaced, and the switch was tested and observed to operate the valve satisfactorily.

j Scheduled Corrective Action ho scheduled corrective action is required.

Actions Taken to Prevent Recurrence No further actions are required.

Generic Implications There are no generic implications based on maintenance history to date.