05000324/LER-1979-041-01, /01T-0 on 790612:during Normal Operation,Reactor Scrammed Due to MSIV Problem & After Scram MSIV Indications Were de-energized.Caused by Power Lead to Dc Solenoid of 2B21-F022D Terminating at Ac Solenoid.Wiring Corrected

/01T-0 on 790612:during Normal Operation,Reactor Scrammed Due to MSIV Problem & After Scram MSIV Indications Were de-energized.Caused by Power Lead to Dc Solenoid of 2B21-F022D Terminating at Ac Solenoid.Wiring Corrected

ML19269E617
Person / Time
Site:	Brunswick
Issue date:	06/26/1979
From:	Tollison A CAROLINA POWER & LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19269E610	List: 05000324/LER-1979-041, Forwards LER 79-041/01T-0 05000324/LER-1979-041-01, /01T-0 on 790612:during Normal Operation,Reactor Scrammed Due to MSIV Problem & After Scram MSIV Indications Were de-energized.Caused by Power Lead to Dc Solenoid of 2B21-F022D Terminating at Ac Solenoid.Wiring Corrected
References
FOIA-81-159 LER-79-041-01T-1, LER-79-41-1T-1, NUDOCS 7906290362
Download: ML19269E617 (2)

LER-1979-041, /01T-0 on 790612:during Normal Operation,Reactor Scrammed Due to MSIV Problem & After Scram MSIV Indications Were de-energized.Caused by Power Lead to Dc Solenoid of 2B21-F022D Terminating at Ac Solenoid.Wiring Corrected

Event date:
Report date:
3241979041R01 - NRC Website

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8 60 61 DOCKET NUMB ER 68 69 EVENT DATE 14 75 REPORT DATE 80 EVENT DESCRIPTION AND PROBABLE CONSEQUENCES h g uring normal plant operation, Unit 2 reactor scrammed due to a MSIV problem. Afterl o

2 Io l3l l the scram, it was noted that indications for the MSIV's were de-energized. Upon in-lo l4 l l vestigation, it was found that one AC and one DC fuse in the MSIV logic circuit had l

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40 di 47 43 44 47 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS h ve perate t c ntr each MSIV. Energizing either solenoip LAn AC and a DC solenoid v i

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LER CONTINUATION -- RO# 1-79-041 Facility:

BSEP Unit No. 2 Event Date:

6-12-79 while the DC system is neutral. Apparently, when an intermittent ground occurred on the DC system, a low impedance path for current was established and the excessive current blew the fuses involved. This de-energized the AC and DC solenoids for the inboard FGIV's causing a scram when they reached less than 107. from full open. The wiring problem was corrected and all other }$1V's were checked and found normal *. A recorder has been connected to the battery ground detector to monitor for intermittent grounds. A procedure is being developed for isolating and clearing DC grounds. This incident will be reviewed by I/C technicians and electricians with the importance of proper terminations stressed.

• MSIV 2B21-F022D was disassembled during the Spring,1979 refueling outage.

The wiring error occurred following reassembly of the valve. The valve operability testing following this maintenance was performed satisfactorily since operation of either solenoid is sufficient to operate the valve.

2147 [UB9