Text

Final Significant Deficiency Rept CP-90-006 Re Loose Auxiliary Switch Linkage in 6.9 Kv Switchgear.Initially Reported on 900404.All safety-related & nonsafety-related Switchgear Will Be Inspected Prior to Fuel Load
	ML20076D598
Person / Time
Site:	Comanche Peak
Issue date:	07/24/1991
From:	William Cahill; TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	; NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
	CP-90-006, CP-90-6, TXX-91255, NUDOCS 9107300045
	Download: ML20076D598 (1)
	v • d • e

<

i 2AC"M

" =:::

i

~

~~

T C

File # 10110 900'3 1UELECTRIC Ref. # 10CFR50,55(e) j July 24, 1991 Williern J. cahill Jr.

T.armene Vwe freudas U. S. Nuclear Regulatory Commissicn Attn:

Document Control Desk Washington, D. C.

20555

SUBJECT:

C0HANCHE PEAK STEAM ELECTRIC STATION (CPSES) - UNIT 2 DOCKET NO. 50 446 6.9KV LOOSE AUXILIARY SWITCH 1.INKAGE SDAR: CP 90-006 (FINAL REPORI UNIT 2)

REF:

1) Til Electric letter logged. TXX-90109 from W. J. Cahill, Jr.

to the NRC, dated April 4, 1990 tientlemen :

On April 4, 1990, via Re'ierence 1. TU Electric notified the NRC of a deficiency involving the 6.9KV switchgear type L2 auxiliary switches.

After an undetermined number of breaker operations, the stud holding nut on the type L2 auxiliary switch linkage may loosen and fall off.

Reference I was an interim response for Unit 2.

This is a final report and provides corrective

. sad preventive action for Unit 2.

TU Electric will inspect safety-related and non-safety related 6.9KV switchgear.L2 auxiliary switches for Unit 2.

Start-up Deficiency Reports have been generated to facilitate these inspections.

If any loose or missing hardware is identified it will be reworked.

Once the stud nuts are securely in place, torque seal, if not already applied, will be applied.

The application of torque seal will permit periodic visual verification of stud nut tightness.

The appropriate preventive maintenance procedure has been revised to provide a verification interval of tightness at 12 to 18 months.

Inspections and rework of the Unit 2 switchgear will be completed prior to Unit 2 f uel load.

Sincerely, William J. Cahill Jr.

By:4 J.

S Harshall Generic Licensing Manager RHS/bm c - Mr, R. D. Martin, Region IV Resident Jnspectors, CPSES (2)

Mr. M. B. Fields 91d7300045 910724 PDR ADOCf: 05000446 400 North Olive Street LB. 81 Dallas, Texas 75201

/

-