ML20009F862

Final Deficiency Rept Re Contact & Indication Malfunctions of Electro Switches Series 20,Type PR-20 & GE Switch S3A Initially Reported 800702.GE Replaced Incorrect Switch on 810323

ML20009F862
Person / Time
Site:	Grand Gulf
Issue date:	07/15/1981
From:	Mcgaughy J MISSISSIPPI POWER & LIGHT CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
10CFR-050.55E, 10CFR-50.55E, AECM-81-253, NUDOCS 8108030113
Download: ML20009F862 (5)

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/]i MISSISSIPPI POWER & LIGHT COMPANY Helping Build Mississippi P. O. B G X 16 4 0. J A C K S O N. M I S S I S S J J) P I 39205

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"$E,.NcYNs7eMR July 15, 1981 Office of Inspection & Enforcement -

U. S. Nuclear Regulatory Commission ,

Region II , 9' , s '

101 Marietta Street, N.W. ,2 '

Suite 3100 d ( $( k \

p42 Atlanta, Georgia 30303 -

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Attention: Mr. J. P. O'Reilly, Director t

Dear Mr. O'Reilly:

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SUBJECT:

Grand Gulf . ation Units 1 and 2 Docket Nos. 50-416/417 File 0260/15525/15526 PRD-80/38, Final Report Electro Switch Malfunctions AECM-81/253 On July 2,1980, Mississippi Power & Light Company notified Mr. F.

Cantrell, of your office, of a Potentially Reportable Deficiency (PRD) at the Grand Gulf Nuclear Station (GGNS) construction site. The deficiency concerns contact and indication malfunctions of Electro Switches Series 20, Type PR-20 and GE Switch Number S3A.

Our investigation into this matter is complete. We have determined that the deficiency identified in I.A. of our report, had it remained uncorrected, would not have adversely affected the safety of operations of the nuclear power plant and is not reportable under the provisions of 10CFR50.55(e).

However, we have determined that the deficiency described in I.B. of our report would have adversely af fected the safety of operations of the nuclear power plant, and is reportable under the provisions of 10CFR50.55(e). Since this equipment had not been turned over to MP&L for acceptance, the deficiency is not reportable by us under the provisions of 10CFR21. Attached is our Final Report.

Yours truly, I i' Y '

I. M!;

J.P.McGaughy,Jr.

KDS:dr ATTACHMENT .y cc: See page 2 5,l i 8108030113 810715 PDR ADOCK 05000416 S PDR Member Middle South Utilities Oystem

Mr. J. P. O'Reilly AECM-81/253 NRC Page 2 cc: Mr. N. L. Stampley Mr. R. B. McGehee Mr. T. B. Conner -

Mr. Victor Stello, Director Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Mr. G. B. Taylor South Miss. Electric Power Association P. O. Box 1589 Hattiesburg, MS 39401 m

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bec: Mr. D. C. Lutken (Final Reports only) Mr. J. E. Letherman Mr. N. L. Stampley, Manager of BWR-6 Licensing '

Mr. J. N. Ward, General Electric Company Mr. W. A. Braun, 175 Curtner Avenue .

Mr. R. S. Trickovic, San Jose, California 95125 Mr. J. W. Yelverton, Mr. L. F. Dale, Mr. Raj Auluck Mr. C. K. McCoy, U. S. Nuclear w gul.itory Connaission '

Mr. T. H. Cloninger, Division of Licensing Mr. R. A. Ambrosino, Washington, D. C. 20555 Mr. R. C. Fron, Mr. G. B. Rogers, Mr. M. R. Williams, Mr. L.*E. Ruhland, ,

Mr. D. L. Hunt, Dr. D. C. Gibbs, -

Mr. A. G. Wagner, Mr. P. A. Taylor, PRD or Inspection Report File File L

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Attechment' to AZCM-81/253 Paga 1 of 2 FINAL REPORT FOR PRD-80/38 This report is divided into two sections which cover two deficiencies experi-enced on the same type switches.

I. Description of the Deficiency A. Electro Switches, Series 20, Type PR-20, supplied by General Electric, showed contact and indication malfunctions during system testing. The malfunction occurs when the switch is turned to the STOP position and released quickly. The internal contact arrangement is such that the AUTO from START position contacts close rather than the AUTO from STOP position contacts. A similar malfunction occurs when the switch is quickly released from the START position. The systems affected by this deficiency are Residual Heat Removal, (E12), Reactor Core Isolation Cooling (E51),

High Pressure Core Spray (E22) and Control Rod Drive Hydraulic (C11)

System. This deficiency applies to both Unit 1 and Unit 2.

The cause of the deficiency is that the operator attempted to oper-ate the switch with a " snap" or " flick" operation. The switch was not designed for this type operation. When the switch is snapped or released quickly, it may allow the memory-type contacts to remain open and the target to hang between positions. This is not a defect -

in the switch, but a characteristic inherent in the design when '

using lateral contacts.

This deficiency is in the NSSS scope of supply. It does not apply to the non-NSSS systems.

II. Analysis of Safety Implications A. Only the operation of the RHR jockey pumps and the switch position -

indicating lights for non-safety-related functions are affected by the misalignment of the switch contacts during " snap" operation.

, The jockey pumps are initiated at plant startup and run continu-ously. They are normally not turned off until plant shutdown.

Primary operating information is provided by control room annuncia-tion for high or low pump discharge pressure and control room indi-cation of system flow. This information is provided by safety-related equipment. Therefore, these switches are safe to be used "as-is" and this condition is not reportable under the provisions of 10CFR50.55(e).

III. Corrective Actions Taken A. Since this condition is not reportable under the provisions of 10CFR50.55(e), no corrective actions are required.

4 Attachm2nt t'o AECM-81/253 Pags 2 of 2 I. Description of the Deficiency B. Electro Switch Number S3A in the Residual Heat Removal System con-tains an additional problem with the internal contact arrangement of the switch. The contacts were arranged such that turning the switch

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to the STOP position would start the RHR pump and vice versa. This deficiency affects the Residual Heat Removal (E12) System and is applicable only to Unit 1.

The cause of the deficiency is installation of the wrong switch.

The deficiency is in the NSSS scope of supply. It does not apply to the non-NSSS systems.

II. Analysis of Safety Implications B. The switch is in an essential circuit in the RHR system. If it was not replaced, the circuit might not function properly if the oper-ator was not observant and did not notice the improper operation r

indicators. Therefore, this condition is reportable under 10CFR50.55(e).

III. Corrective Actions Taken B. GE issued FDDR JB1-1068 to replace the wrong switch (S3A) with the -

correct switch. This was accom'plished at the site on March 23, 1981. Since this was an isolated case, no actions are necessary to prevent recurrence.

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