ML19312E330

Final Deficiency Rept Re Broken Insulators on 7kV Speed & Transfer Switches.Mfg Will Provide New,Heavier Shafts on Operating Mechanism & Welded Cranks to Reduce Deflection. Operating Angle of Cranks Will Also Be Changed

ML19312E330
Person / Time
Site:	Summer
Issue date:	05/28/1980
From:	Crews E SOUTH CAROLINA ELECTRIC & GAS CO.
To:
References
NUDOCS 8006040241
Download: ML19312E330 (3)

Text

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• D.d:a.4 05oj aiT Sours CAROLINA ELECTRIC a gas COMPANY nose ossect son ,..

CotumelA,Sourn CAnoLINA asais E. H. Catws, J a.

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c...........c...... May 28, 1980 Mr. James P. O'Reilly, Director U. S. Nuclear Regulatory Commission Region II, Suite 3100 101 Marietta Street, N.W.

Atlanta, Georgia 30305

Subject:

Virgil C. Summer Nttelear Station Reportable Substantial Safety Hazard Speed and Transfer Switch Insulators Nuclear Engineering File 3.1051

Dear Mr. O'Reilly:

On 4/30/80, a substantial safety hazard as defined by 10CFR21 was reported to NRC resident inspector Jack Skolds on the subject of broken insulators on 7kV speed a transfer switches. Details are given on the attachment. The safety h ard :s being reported under our 10CFR50.55(e) procedure. This is consi er d .1 final report on the eter.

Ve y ly yours, .

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E. H. ws, Jr.

JAW:EHC:rh cc: H. T. Babb

• E. H. Crews, Jr.

0. S. Bradham D. R. Moore H. Radin J. Skolds V. C. Summer l NPCF/Dixon -

File Document Management Branch Washington, D.C.

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80 0604 0M/

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O 10CFR21 - SUBSTANTIAL SAFETY HAZARD

1. Name and Address of Reporting Individual James A. 'n' actor South Carolina Electric & Gas Co.

P. O. Box 764, Columbia, S.C. 29218

2. Identification of Basic Component 7kV Speed and Transfer Switches

3. Identification of Firm Supplying Component

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Gould-Brown Boveri i

4. Nature of Defect, Substantial Safety Hazard Created, and Evaluation The purpose of the speed and transfer switch is to change speeds on two speed

.4 motors and transfer power sources on swing equipment. The insulator between the operating mechanism and the switch blade has been breaking on the speed switches.

The speed switches for the service water pumps autocatically switch to high speed on safety injection to " provide extra cooling for the reactor building cooling units. A broken insulator could prevent the service water pumps from starting, thus creating a substantial safety hazard.

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5. Date Information of Defect Was Obtained - October 4, 1979

6. Number and location of Defect Insulators have brok=n in the service water pump speed switch, XES 2003B and component cooling pump speed switches, XES 2001A and XES 2001B.

7. Corrective Action The manufacturer has been called in and has proposed a solution. They will provide new, heavier shafts on the operating mechanism and welded cranks to reduce the deflection in the mechanism. The operating angle of the cranks will also be changed.

I The proposed solution has been accepted, and the new shafts are scheduled i June 9, 1980. The shafts on the speed switches and the transfer switches will be replaced.

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8. Advice to Purchasers or Licensees None.

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