ML19337B649

Fifth Interim Deficiency Rept Re Inadequate Crimps on Connector Pins for Power Generation Control Complex Interconnecting Cables.All GE Tests Have Been Completed.Util & Constructor Are Reviewing Test Results

ML19337B649
Person / Time
Site:	Grand Gulf
Issue date:	09/30/1980
From:	Mcgaughy J MISSISSIPPI POWER & LIGHT CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
AECM-80-239, NUDOCS 8010080416
Download: ML19337B649 (3)

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C-1 MISSISSIPPI POWER & LIGHT COMPANY Helping Build Mississippi P. O. B O X 1840, J ACK S O N, MIS SISSIP PI 3 92 05 I

awes p. 5- mv an. September 30, 1980 asucunvcenuma n Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission

' Region II 101 Marietta Street, N.W.

Suite 3100 Atlanta, Georgia 30303

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Attention: Mr. J. P. O'Reilly, Director Dear Mr. O'Reilly*

SUBJECI: Grand Gulf Nuclear Station Units 1 and 2 Docket Nos. 50-416/417 j' File 0260/15525/15526 PRD-79/04, Interim Report No. 5, Inadequate Crimping in PGCC 1 Cable Pin Connectors AECM-80/239 1

References:

1) AECM-79/26, 3/27/79

. 2) AECM-79/54, 5/29/79

3) AECM-80/126, 11/19/79

4) AECM-80/18, 1/31/80 On February 23, 1979, Mississippi Power & Light Company noti-fied Mr. W. B. Kenna of your office of a Potentially Reportable De-ficiency (PhD) et the Grand Gulf Nuclear Station (GGNS). The de-ficiency concuns inadequate crimping on certain Power Generation

, Control Complex (PGCC) interconnecting cable pin connections sup-plied by the General Electric Company.

General Electric has completed all testing and inspections re-quired for our evaluation. However, we will require more time to review the adequacy of their tests. We now expect to send you our Final Report on this matter by February 11, 1981. Our Interim Report is attached.

Yours truly, Y

J. P. McGaughy, Jr.

pI4 WDH:st Attachment hI I ec: Mr. N. L. Stampley Mr sVi.ctor Stallo, Director Mr. R. B. McGehee. Division of Inspection & Enforcement Mr. T. B. Conner U. S. Nuclear Regulatory Commission

"* i C 00g Member Middie You"cDeiliSies SNiem

INTERIM REPORT NO. 5 FOR PRD-79/04 I. Description of Deficiency Certain Power Generation Control Complex (PGCC) interconnecting cables supplied by the General Electric Company have inadequate crimps on the connector pins. This deficiency was noted in January 1979 from inspections made on similar equipment for the Susquehanna Nuclear Station. Pennsylvania Power & Light Company notified USNRC Region I of the deficiency on January 9, 1979. Subsequent investigations con-ducted by Bechtel Power Corporation revealad that the potential for similar conditions existed at the Grand Gulf Nuclear Station (GGNS).

MP&L then reported this condition to USNRC Region II as a Potentially Reportable Deficiency (PRD) on February 23, 1979. Later, Mr. D. K.

Walters of USNRC Region II visited the GGNS construction site and issued a Notice of 71olation (Infraction) which addressed inadequate pull testing of conductors in cables for the PGCC (Raference NRC letter to MP&L, dated October 18, 1979).

The pull testing procedure referenced in the NRC Notice of Violation relates to this deficiency in that the inspections for crimp strength at GGNS for the PGCC interconnecting cables are made using that pro-cedure. G.E. has determined through preliminary tests that a pull test value of 15 pounds for 16 AWG Wire and 8 pounds for 20 AWG is sufficient to ensure that the connectors possess adequate electrical and mechanical pr>perties. This information on the Notice of Vio-lation has been provided to USNRC Region II as noted in the MP&L letter to USNRC Region II, dated January 15, 1980. G.E. has com-pleted a full range of tests confirming these preliminary results.

MP&L is. currently reviewing these test results. l II. Proposed Resolution MP&L has implemented the following program through GE and the con- I structor for insuring that the connectors for the interconnecting l cables in the PGCC have adequately crimped pin connections:

1. Performed an inspection of interconnecting cables on the Unit 1  ;

PGCC. Repaired and reinspected cables as required. '

2. Evaluated interconnecting cab'les fabricat'ed with connectors at the General Electric factory in San Jose, Calif. Any deficiencies noted in the evaluation, including pin crimping, manufacturing &

QA processes, procedures, tooling and records were documented for correction. The following steps were performed on cables found to have been pin crim,7 pull tested in excess of allovable yield strength linits:

a. Conducted an engineering evaluation of the acceptability of these cables for their intended service without terminating connector ends, and

b. Reterminated cable ends at GGNS for those cables that were l on critical path preoperational schedules pending findings I of engineering evaluation items in step 2(a).

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3. General Electric has modified their manufacturing processes to  ;

eliminate the problem of inadequate pin crimping on Unit 2 PGCC interconnecting cables.

l III. Status of the Proposed Resolution

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All GE tests have been completed. MP&L and their Constructor are reviewing the test report submitted by GE.

i l l IV. Reason for Delay in Final Report j

i Test results are still being evaluated by MP&L and their Constructor. -

V. Projected Final Report Submittal Date February 11, 1981 l

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