ML20012F573

Final Deficiency Rept CP-90-005 Re Installed Fuse Types & Sizes Not Consistent w/one-line Drawings.Intially Reported on 900305.Fuses Removed & Reinstalled to Deenergize or Reenergize Circuits or Equipment,Per Clearance Procedure

ML20012F573
Person / Time
Site:	Comanche Peak
Issue date:	04/04/1990
From:	William Cahill TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
CP-90-005, TXX-90111, NUDOCS 9004160186
Download: ML20012F573 (3)

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2 ""* Log # TXX 90111 i

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J File # 10110 i

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908.3  !

W . # 10CFR50.55(e) {

nlELECTRIC i

I April 4. 1990 j witham J, cahill, Je. j tm.at., sw huww i

U. S. Nuclear Regulatory Commission '

Attn Document Control Desk i Washington D. C. 20555 i i

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$UBJECT: COMANCHE PEAK STEAM ELECTRIC STATION (CPSEb)  :

DOCKET NOS 50 445 AND 50 446 i FUSE SIZE / TYPE INCONS!$TENCIES i SDAR: CP 90 005 (FINAL REPORT) '

, i j Gentlemen  !

On March 5. 1990. TU Electric orally notified the NRC of a potentially j reportable deficiency concerning installed fuse types and sizes which were not  ;

4 consistent with one line drawings. After further review, it has been  !

! concluded that this deficiency meets the criteria for reportability pursuant i to 10CFR50.55(e) and the required information follows.  !

Description i

The Operational Readiness Assessment Team (0 RAT) expressed a concern regarding  ;

lack of fuse verification as pt.-t of electrical system lineups. A walkdown (

was initiated and a number of discrepancies were observed. The investigation j revealed the causes of this deficiency to be the kilowing. lt

1. Fuse manufacturer or type was nos ,,yecified adequately on design  !

documents by Engineering.

2. Startup procedures did not require that the fuse manufacturer or  ;

l type be verified prior to installation. l l  !

3. The Operations procedure for removing and reinstalling fuses did not  ;

require that the manufacturer, type, or size be verified prior to  !

installation, i Fuses are removed and reinstalled by the Operations department to deenergize  !

or reenergize circuits or equipment in accordance with a clearance procedure.

An evaluation was performed of other similar devices that are removed and I installed in the same manner and that could result in an impact on safety by l inadvertently installing the incorrect device. TV Electric has concluded that  ;

this problem is limited to fuse installations,  !

i 9004160186 900404 .

PDR ADOCK 0500044.s ,

s PDC  :

7  !

400 North Olive street LB. si Dallas, Tenas 75201  !

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TXX 90111 l April 4. 1990 Page 2 of 3 Safety Sionificanct Fuses supplied by manufacturers are specified by type and size to ensure that equipment operates reliably and that equipment and personnel are protected by deenergizing equipment in the event of an electrical fault. Furthermore, calculations utilizing data provided by equipment vendors ensure proper fuse coordination. Fuses that deviate from the toeionent manufacturers' specifications may create improper fuse coormiation or otherwise impact operation of the associated equipment. Had this condition remained uncorrected it could have adversely affected the safety of plant operations and is considered reportable pursuant to 10CFR50.55(e).

Corrective Actien A ONE Form and Oorrective Action Request (CAR) 90 01 were initiated to document and evaluate this condition. TU Electric verified the installed fuses specified in the Device Level One Line Diagrams. as described below.

This action, combined with routine testing and surveillance, assures reliable component functioning.

Engineering prepared packages fo' each component or cabinet and Operations walked the equipment down. listing the fuse size, type, and manufacturer for each fuse installed. Engineering eva1LtTed the walkdown results and listed discrepancies in a database. The discrepancies were separated into the following categories:

1. Wrong size (amperage rating) fuse installed

2. Wrong type or manufacturer fuse installed

3. Fuse type or manufacturer not specified

4. Removed or (C eterminate fuses Each fuse discrepancy was resolved by installing the specified fuse or by showing through analysis that the installed fuse was acceptable, thereby Diagramsthat ensuring fuses for Unit 1. are installed in accordance with tho Device Level One Line Preventive ActiDa In order to prevent recurrence. STA 605 has been revised to require that the -

fuse type and size be verified to be in accordance with desion documents when both removing or reinstalling fuses for clearances. As an interim measure prior to the revision of procedure STA 605. TU Electric, subsequent to the l t

verification of installed fuses, initiated a standing shift order that assured that when fuses were removed they were reinstalled properly.

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TXX 90111 April 4, 1990 Page 3 of 3 For Unit 2. TV Electric wl11 review and revise, as necessary, startup procedures for initial installation of fuses and for the subsequent removal and reinstallation of fuses to ensure that the specified fuse type and size are installed. Additionally, Device Level One Line Diagrams will be developed for Unit 2 whicii will specify fuse size, type and manuf acturer. A b verification that installed fuses conform with these diagrams will be performed prior to fuel load for Unit 2.

Sincerely.

f:N William J. Cahill, Jr.

WJH/vid c Mr. R. D. Martin, Region IV Resident inspectors, CPSES (3)

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