05000369/LER-1982-051, Forwards LER 82-051/03L-0.Detailed Event Analysis Encl

Forwards LER 82-051/03L-0.Detailed Event Analysis Encl

ML20055B050
Person / Time
Site:	McGuire
Issue date:	07/09/1982
From:	Parker W DUKE POWER CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20055B051	List: 05000369/LER-1982-051, Forwards LER 82-051/03L-0.Detailed Event Analysis Encl 05000369/LER-1982-051-03, /03L-0:on 820608,125-volt Battery Evca Returned to Svc Prior to Verification of Operability.Caused by Personnel Error.Battery Reisolated & Operability Verified.All Employees Cautioned.Procedure Modified
References
NUDOCS 8207200298
Download: ML20055B050 (3)

LER-1982-051, Forwards LER 82-051/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
3691982051R00 - NRC Website

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ANCAg04 WILLIAM O. PARM ER, J R.

July 9, 1982

%Cr PatSIDENT TE L E PMO N E Segue PooovCTioN 373-4083 Mr. James P. O'Reilly, Regional Administrator U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, Suite 3100 Atlanta, Georgia 30303 Re: McGuire Nuclear Station Docket No. 50-369

Dear Mr. O'Reilly:

Please find attached Reportable Occurrence Report R0-369/82-51. This report concerns T.S.3.8.2.3, "The following D.C. channels shall be operable and energized: a. Channel I consisting of 125-volt DC bus no. EVDA, 125 volt-DC' battery bank no. EVCA at,.I a full capacity charger..."; and T.S.6.9.1.13(c),

" Observed inadequacies in the' implementation of administrative or procedural-controls which threaten to cause reduction of degree of redundancy provided in Reactor Protection Systems or Engineered Safety Feature Systems or Engineered Safety Feature Systems". This incident was considered to be of no significance with respect to the health and safety of the public.

l Very truly your N,

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d, William O. Parker, Jr PBN/jfw Attachment cc: Director Records Center Office of Management and Program Analysis Institute of Nuclear Power Operations

- U. S. Nuclear Regulatory Commission 1820 Water Place Washington, D. C.

20555 Atlanta, Georgia 30339 Mr. P. R. Bemis Senior Resident Inspector-NRC McGuire Nuclear Station Q{:{.NU G207200298 820709 DR AD00K 05000 f f,."2, &

DUKE POWER COMPANY McGUIRE NUCLEAR STATION REPORTABLE OCCURRENCE REPORT NO. 82-51 REPORT DATE: July 9, 1982 FACILITY: McGuire Unit 1, Cornelius, NC IDENTIFICATION: Vital Instrument and Control Battery EVCA Was Placed In Service While Technically Inoperable

DESCRIPTION

On June 8, 1982, 125V battery EVCA was returned to service before its operability had been verified following a discharge service test.

Battery EVCA was removed from service on June 7, for the 18 month"125V DC vital I6C battery discharge service test".

Its associated bus, 125VDC Vital Instrument and Control Distribution Center EVDA, was connected to 125VDC bus EVDC and then isolated from the battery. After the discharge test was completed, the battery was recharged by alterr.ately using charger EVCA and the constant current charger.

The battery was then reconnected to charger EVCA which was aligned to the low voltage or float charge mode to allow the battery to cool down in preparation for the post charging, operability measurements. During a chance meeting between the shift supervisor and the technician, the supervisor questioned the technician about the results of the discharge test and what remaining work was necessary to return the battery to an operable status. The technician replied that the discharge test had gone well and that the monthly battery parameter readings had to be taken.

Not realizing that the monthly readings were being used to verify that the battery had been properly recharged, the shift supervisor assumed that the battery had been verified good. He instructed a nuclear equipment operator (NEO) to reconnect battery EVCA to bus EVDA and open the tie breakers connecting EVDA to EVDC. The technician later returned to the battery area to check on the battery. He found the battery charger current much too high to be supplying the battery alone and subsequently found the battery and charger reconnected to bus EVDA. He informed the current shift supervisor (shift change had occurred) that battery EVCA was not technically operable. The battery was subsequently isolated from the bus.

The unit was operating at 75% during the incident.

This incident was the result of Personnel Error as the shift supervisor failed to verify that battery EVCA was technically operable before returning it to service.

EVALUATION: When the shift supervisor discussed the battery discharge test results and the steps remaining to complete the periodic test with the technician on June 8, he got the impression that the battery had been verified operable. He did not realize that the monthly battery parameter measurements were to be used to verify the battery recharge.

During the monthly periodic test, these parameters are measured with the battery in service. Key words like " operable" and " technical specifications" were not used in the discussion.

Another factor that could have affected the shift supervisor's decision was pre-mature clearance of the red tag (issued to tag open battery EVCA circuit breaker for the service discharge test) when battery EVCA was placed on float charge on June 8.

When a red tag is issued for this type of work, it is usually hung and lifted as needed to do the job and then cleared when the work is complete.

In

Report No. 82-51 Page 2

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this case the technician cleared the first red tag on June 8, and another red.

. tag had to be issued to cover the intercell resistance measurement work on June 9.

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Battery EVCA was only technically inoperable when it was connected to bus EVDA on June 8.

Subsequent voltage and specific gravity measurements verified that the recharged' battery was operable per Technical Specification criteria. Although j

bus EVDA was made technically inoperable when the EVCA was connected to it on June j

8, it remained connected less than the two hour period allowed by Technical Speci-fication 3.8.2.3.

The shif t supervisor did consider the operability of battery EVCA before having -it t

returned to service. The information he used to make this decision, however, was based partially on the implications of events and not strictly on facts gained.

from the technician. In this event, as in incidents before, if the questions and answers had been more specific and complete, the error would have been avoided.

SAFETY ANALYSIS

Battery EVCA was' properly recharged and functionally operable 3

when it was reconnected to bus EVDA on June 8.

The health and safety of the public i

were unaffected by this incident.

i

CORRECTIVE ACTION

Immediate corrective action upon discovering battery EVCA in service on June 8, was to isolate it from bus EVDA. Verification of operability of the battery was completed on June 9, and the battery and bus were declared j

operable.

This incident will be covered with all station employees. They will be cautioned to improve the communication of vital information between themselves and other employees.

Operating Procedure "?25VDC/120VAC Vital Instrument and Control" has been modified j

to include a section written specifically for battery testing. The procedure requires that the vital bus main breaker be white tagged open throughout the test.

The tag can only be cleared when the instrumentation and electrical (IAE) group determines that the battery is operable.

This white tag is in addition to whatever l

red tags are required for the work.

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