ML20076C043

First Interim Deficiency Rept of Significant Const Deficiency 86 Re Burned 3A-2 Safety Inverter Output Capacitor wiring.Push-on Connectors Caused Burning.Output Leads to Be Soldered to Capacitors.Final Rept by 830915

ML20076C043
Person / Time
Site:	Waterford
Issue date:	08/05/1983
From:	Drummond F LOUISIANA POWER & LIGHT CO.
To:	Jay Collins NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
10CFR-050.55E, 10CFR-50.55E, W3I83-0269, W3I83-269, NUDOCS 8308220191
Download: ML20076C043 (3)

Text

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i Louisiama P O W E R & LI G H T 7 NEW OALEANS LOU!SIANA

,..ee-c~ce eer . mecxecce 70174 m O (504)366-2345 MIDDLE SOUTH UTIUTIES SYSTEM August 5, 1983 3I83 92 N ff b Y N gi588 Mr. John T. Collins, Regional Administrator, Region IV U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76012

SUBJECT:

Waterford SES Unit No. 3 Docket No. 50-382 Significant Construction Deficiency No. 86 "3A-S Safety Inverter Output Capacitor Wiring Burned" First Interim Report

REFERENCE:

Telecon dated July 8, 1983 from D. E. Baker to W. Crossman

Dear Mr. Collins:

In accordance with the requirements of 10CFR50.55(e), we are hereby providing two copies of the Interim Report of Significant Construction Deficiency No. 86, "3A-S Safety Inverter Output Capacitor Wiring Burned." This item was previously identified as PRD 119.

If you have any questions, please advise.

Very truly yours, F. J. Drummond Y& .= - -

Manager Engineering & Technical Services FJD/WAC/ MAL;keh Attachment cc: 1) Director 3) Mr. E. L. Blake Office of Inspection & Enforcement U.S. Nuclear Regulatory Commission Washington, D.C. 20555

2) Director 4) Mr. W. M. Stevenson Office of Management Information and Program Control U.S. Nuclear Regulatory Commission ,

Washington, D.C. 20555 8308220191 830805 ~

'd b - y PDR ADOCK 05000382 S PDR

- - - - - - - - _ l}$

INTERIM REPORT OF SIGNIFICANT CONSTRUCTION DEFICIENCY NO. 86 "3A-S SAFETY INVERTER OUTPUT CAPACITOR WIRING BURNED" INTRODUCTION This report is submitted pursuant to 10CFR50.55(e) . It describes a deficiency in the output capacitor wiring of 10 KVA inverters supplied by the Elgar Corpo-ration. The problem is considered reportable under the requirements of 10CFR50.55(e). To the best of our knowledge, this problem has not been identi-fied to the Nuclear Regulatory Commission pursuant to 10CFR21.

DESCRIPTION OF PROBLEM During periodic inspection by LP&L startup personnel it was discovered that the output capacitor wiring of the 3A-S inverter (supplied by Elgar) was burned.

This problem was traced to the use of push-on connectors at the capacitors resulting in a high resistance connection and subsequent heating. The 3B-S inverter was subsequently inspected and the same problem was identified.

The 3A-S and 3B-S inverters supplied by Elgar are part of the 120 volt uninterr-uptible AC system described by FSAR section 8.3. They supply power to safety related loads including solenoid valve operators, radiation monitors and auxiliary isolation relay panels. The four Plant Protection System inverters are manufactured by a different vendor and not involved in this deficiency.

SAFETY IMPLICATION Loss of the 3A-S or 3B-S inverter would lead to loss of its respective safety related loads until an operator was able to perform a local manual transfer to the bypass supply (480V Motor control Center 3A-313-S or 3B-313-S). This deficiency would, therefore, have resulted in delay or inoperability of safety related functions in an accident situation.

CORRECTIVE ACTION Elgar has investigated this problem and determined that it is best corrected by l soldering the output leads directly to capacitors, thereby eliminating the high resistance push-on connectors. Nonconformance Report W3-6510 has been generated to document and track this deficiency. Corrective action is scheduled for completion by August 31, 1983. A Final Report will therefore be submitted to the NRC by September 15, 1983.

F l e INTERIM REPORT OF SIGNIFICANT CONSTRUCTION DEFICIENCY NO. 86 "3A-S SAFETY INVERTER OUTPUT CAPACITOR WIRING BURNED" INTRODUCTION This report is submitted pursuant to 10CFR50.55(e). It describes a deficiency in the 7utput capacitor wiring of 10 KVA inverters supplied by the Elgar Corpo-ration. The problem is considered reportable under the requirements of 10CFR50.55(e). To the best of our knowledge, this problem has not been identi-fied to the Nuclear Regulatory Commission pursuant to 10CFR21.

DESCRIPTION OF PROBLEM During periodic inspection by LP&L startup personnel it was discovered that the output capacitor wiring of the 3A-S inverter (supplied by Elgar) was burned.

This problem was traced to the use of push-on connectors at the capacitors resulting in a high resistance connection and subsequent heating. The 3B-S inverter was subsequently inspected and the same problem was identified.

The 3A-S and 3B-S inverters supplied by Elgar are part of the 120 volt uninterr-uptible AC system described by FSAR section 8.3. They supply power to safety related loads including solenoid valve operators, radiation monitors and auxiliary isolation relay panels. The four Plant Protection System inverters are manufactured by a different vendor and not involved in this deficiency, SAFETY IMPLICATION Loss of the 3A-S or 3B-S inverter would lead to loss of its respective safety related loads until an operator was able to perform a local manual transfer to the bypass supply (480V Motor Control Center 3A-313-S or 3B-313-S). This deficiency would, therefore, har. resulted in delay or inoperability of safety related functions in an accident situation.

CORRECTIVE ACTION Elgar has investigated this problem and determined that it is best corrected by soldering the output leads directly to capacitors, thereby eliminating the high resistance push-on connectors. Nonconformance Report W3-6510 has been generated to document and track this deficiency. Corrective action is scheduled for completion by August 31, 1983. A Final Report will therefore be submitted to the NRC by September 15, 1983.

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