ML19331B630

Interim Deficiency Rept Re Contact & Indication Malfunction of Series 20,Type PR-20 Electro Switches.Evaluation Incomplete.Determination of Reportability & Final Rept Will Be Sent by 801028

ML19331B630
Person / Time
Site:	Grand Gulf
Issue date:	07/30/1980
From:	Mcgaughy J MISSISSIPPI POWER & LIGHT CO.
To:
References
AECM-80-172, NUDOCS 8008120514
Download: ML19331B630 (3)

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CA _U MISSISSIPPI POWER & LIGHT COMPANY i -] Helping Build Mississippi Em M P. O. S C X 16 4 0, J A C K S O N MIS SIS SIP PI 3 9 2 0 5 sve:. EAR PACoUCTioN CEPARTMENT July 30, 1980 Office of Inspection & Enforcement U. S. Nuclear Regulatory Cet: mission Region II 101 Marietta Street, N.W.

Suite 3100 Atlanta, Georgia 30303 Attention: Mr. J. P. O'Reilly, Director

SUBJECT:

Grand Gulf Nuclear Station Units 1 and 2 Docket Nos. 50-416/417 File 0260/15525/15526 PRD-80/38, Status Report, Electro Switch Malfunctions AECM-80/172 On July 2, 1980, Mississippi Power & Light notified Mr. F.

Cantrell of a Potentially Reportable Deficiency (PRD) at the Grand Gulf Nuclear Station (GGNS) construction site. The deficiency con-cerns contact and indication malfunctions of Electro Switches, Series 20, Type PR-20.

The scope of our investigation has been expanded to include an additional problem with Electro Switches. Our investigation and

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evaluation have not been completed. Details are in the attached status report.

We expect to determine reportability and submit a final report by October 28, 1980.

Yours truly, Jg' b ,w0J (-

k J. P. McGaughy, Jr.

Assistant Vice President,

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Nuclear Production I

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AIR:st Attach =ent

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80081205/#[ Member Middle South uenicies System

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MIENCCIPPI POWER O LIGHT COMPANY I

l Mr. J.'P. O'Reilly AECM-80/172 NRC Page 2

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i cc: Mr. N. L. Stampley Mr. R. B. McGehee Mr. T. B. Conner i

j Mr. Victor Stello, Director -

g Division of Inspection & Enforcement ..

U. S. Nuclear Regulatory Commission Washington, D.C. 20555 i

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4 Attach::st to AECM-80/172

' Pega 1 of 1 STATUS REPORT. PRD-80/38 I. Descriotion of Deficiency

a. Electro Switches, Series 20, Type PR-20, supplied by General Electric, shewed contact and indication =alfunctions during system testing. The malfune:1cn is when the switch is turned to the STOP position and released quickly, the internal cen-tact arrange =ent is such that the AUTO fres START position contacts close.rather than the AUTO frca STOP positica centacts.

A similar =alfunction occurs when the switch is quickly re-leased frc= the START position. Three (3) sweiches (No. 53A, S33, 53C) which experienced this =alfunction are used in the Residual Heat Removal (RER) System.

b. Electro Switch, GE Switch Number S3A, contains an additienal probles with the internal contact arrange =ent of the switch.

The contacts are arranged such that turning the switch to the STOP positien vould start the RER pu=p and vice versa. This switch controls RER Pump "A". ,

II. Safety Implications The evaluation as to the safety implicatiens has not been ecmpleted by cur NSSS supplier.

III. Corrective Action Taken

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Corrective actions are centingent on the results of the evaluation of safety i=plications.

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