ML18102A358

LER 96-008-00:on 960729,battery Chargers Were Declared Inoperable Due to Mfg Discrepancies.Unit 2 Battery Chargers Will Be Reworked to Design Specifications by 960915.W/960824 Ltr

ML18102A358
Person / Time
Site:	Salem
Issue date:	08/24/1996
From:	Garchow D, Hassler D Public Service Enterprise Group
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
REF-PT21-96 LER-96-008-02, LER-96-8-2, LR-N96265, NUDOCS 9609100105
Download: ML18102A358 (6)

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e e OPS~G Public Service Electric and Gas Company P.O. Box 236 Hancocks Bridge, New Jersey 08038-0236 Nuclear Business Unit AUG 241996 LR-N96265 U. s. Nuclear Regulatory Conunission Document Control Desk Washington, DC 20555 Gentlemen:

LER 311/96-008-00 SALEM GENERATING STATION - UNIT 2 FACILITY OPERATING LICENSE NO. DPR-75 DOCKET NO. 50-311 This Licensee Event Report entitled ~Inoperable Battery Chargers Due To Manufacturing Discrepancies" is being submitted pursuant to the requirements of the Code of Federal Regulations 10CFR50.73(a) (2) (v), 10CFR50.73(a) (2) (vii), and 10CFR21.2(c).

Q:;7:~r~L)

David F. Gal._

• General Manager _

Salem Ope~ations Attachment SORC Mtg.96-114 JMO/tcp C Distribution LER File 3.7 9609100105 960824 PDR ADOCK 05000311

~;i/r S PDR 1he po.ver is in }OUr hands.

95-2168 REV. 6/94

Document Control Desk LR-N96265 Attachment A The following items represent the commitments that Public Service Electric & Gas (PSE&G) made to the Nuclear Regulatory Commission (NRC) relative to this LER (311/96-008-00). The commitments are as follows:

1. The Unit 2 battery chargers will be reworked to design specifications by September 15, 1996.

2. The Unit 1 battery chargers will be reworked to design specifications prior to installation in Unit 1. Testing will follow installation.

3. PSE&G Nuclear Procurement and Materials Management is undertaking an investigation of common cause analysis for procurement concerns identified as a result of LER 272/96-009-00, LER 272/96-014-00, this LER, and a recent 10CFR21 report concerning defects found in NUS logic modules. Further corrective actions will be taken as a result of the evaluation currently being conducted. Significant corrective actions that affect the discussion in this LER, if any, will be reported in a supplement to this LER.

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY DMB ND. 3150-0104 (4-95) EXPIRES 04/30/98

. ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS MANDATORY INFORMATION COLLECTION REQUEST: 50.0 HRS. REPORTED LESSONS LEARNED ARE INCORPORATED INTO THE LICENSING PROCESS AND FED BACK TO INDUSTRY. FORWARD COMMENTS REGARDING LICENSEE EVENT REPORT (LERI BURDEN ESTIMATE TO THE INFORMATION AND RECORDS MANAGEMENT BRANCH (T-6 F33),

U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF MANAGEMENT AND BUDGET, (See reverse for required number of WASHINGTON, DC 20503.

digits/characters for each block)

FACILITY NAME 111 DOCKET IUMBER 121 PAGE Ill SALEM GENERATING STATION UNIT 2 05000311 1 OF 4 TITLE 141 Inoperable Battery Chargers Due To Manufacturing Discrepancies EVENT DATE (5) LER NUMBER (6) REPORT DATE (7) OTHER FACILITIES INVOLVED (8)

FACILITY NAME DOCKET NUMBER MOITH DAY YEAR YEAR I SEDUENTIAL NUMBER I REVISION NUMBER MONTH DAY YEAR Salem Unit 1 FACILITY IAME 05000272 DOCKET .UMBER 07 29 96 96 - 008 - 00 08 24 96 OPERATING N THIS REPORT IS SUBMITTED PURSUANT TD THE REQUIREMENTS OF 10 CFR §:(Check one or more) (11)

MODE (9) 2D.2201(b) 20.2203(a)(2)(v) 50.73(a)(2)(i) 50.73(a)(2)(viii)

POWER 000 2D.2203(a)(1) 20.2203(a)(J)(i) 5D.73(a)(2)fli) 50.73(a)(2)(x)

LEVEL (10) 20.2203(a)(2)(i) 20.2203(a)(3)(ii) 50.73(a)(2)flii) 73.71 2D.2203(a)(2)(ii) 20.2203(a)(4) 50.73(a)(2)flv) x OTHER 20.2203(a)(2)flii) 50.36(c)(1) x 50.73(a)(2)(v) s,.c:ify i1 Ah1nd H!.w er 11 H.C Fuin JIBA 20.2203(a)(2)(iv) 50.36(c)(2) x 50.73(a)(2)(vii) Part 21 LICENSEE CONTACT FOR THIS LER (12)

NAME TELEPHOIE NUMBER (lncludo ArH Codel Dennis v. Hassler, LER Coordinator 609-339-1989 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

CAUSE SYSTEM COMPONEIT MAIUFACTURER REPORTABLE CAUSE SYSTEM COMPOIEIT MAIUFACTURER REPORTABLE TO IPRDS TO NPRDS B EJ BYC C127 y :1111111111111111111:1111111 mm~~~~r~rir 1:11111111111:1111111:1:111::

SUPPLEMENTAL REPORT EXPECTED 114) EXPECTED MONTH DAY YEAR

'YES (If yes, complete EXPECTED SUBMISSION DATE).

x IND SUBMISSION DATE (15)

ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) (16)

On July 27, 1996, while trouble shooting wiring discrepancies during pre-installation testing of the 2A2 125V DC Battery Charger {EJ/BYC} (C&D Charter Power Company model ARR130H300F), a terminal block screw ejected from its terminal. Subsequent inspection of the other newly installed battery chargers on Unit 2 as well as other battery chargers awaiting installation for Unit 1 revealed a number of discrepancies. Based upon these discrepancies, on July 29, 1996, all remaining Unit 2 battery chargers were maintained available, but were declared to be inoperable due t:o :;oncerns about seismic qualification. The replacement Unit 1 battery cha ~gE ::s remained in storage. There was no impact on Unit 1 as a result of the battery charger discrepancies.

The apparent cause C' "f the discrepancies identified is poor workmanship during manufacturing and s:::ipping damage.

This event is reportable in accordance with 10 CFR 50.73(a) (2) (v), any condition that alone could have prevented the fulfillment of the safety function for structures or systems that are needed to mitigate the consequences of an accident and in accordance with 10 CFR 50.73(a) (2) (Vii) I any event where a single cause or condition caused at two independent trains to become inoperable in a single system designed to mitigate the consequences of an accident.

This event is also reportable per 10 CFR 21.2(c)

NRC FORM 366 (4-95)

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (4-95)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME {1) DOCKET NUMBER {2) LER NUMBER {6) PAGE {3) 05000311 YEAR I SEOUEllTIAL NUMBER I RmSION llUIWIER 2 OF 4 SALEM GENERATING STATION UNIT 2 96 - 008 - 00 TEXT {If more space is required, use additional copies of NRC Form 366A) (17)

PLANT AND SYSTEM IDENTIFICATION Westinghouse - Pressurized Water Reactor 125 VDC Power System - Class lE/Battery Charger {EJ/BYC}*

• Energy Industry Identification System (EIIS) codes and component function identifier codes appear as (SS/CCC)

CONDITIONS PRIOR TO OCCURRENCE At the time of identification, Salem Units 1 and 2 were shutdown and defueled.

DESCRIPTION OF OCCURRENCE On July 27, 1996, while trouble shooting wiring discrepancies identified during pre-installation testing of the High Voltage Shutdown (HVSD) Board on the newly installed 2A2 125V DC Battery Charger {EJ/BYC} (C&D Charter Power Company model ARR130H300F), the HVSD board terminal block (-) DC terminal screw ejected from its terminal. Subsequent inspection of the other newly installed battery chargers on Unit 2 as well as other battery chargers awaiting installation for Unit 1 revealed a number of discrepancies. On July 29, 1996, all remaining Unit 2 battery chargers were maintained available, but were declared to be inoperable due to concerns about seismic qualification. The replacement Unit 1 battery chargers remained in storage. There was no impact on Unit 1 as a result of the battery charger discreDancies since the Unit 1 chargers are a different design.

The discrepancies listed below represent a general list of manufacturing deficiencies found i~ these safety related pieces of equipment:

• broken welded mounting brackets for the filter choke and DC Capacitor assembly

• loose and/or missing mounting bolts on the transformers

• strands of wires not properly soldered

• loose wire terminations

• plastic lock-in ~tandoff tabs broken and r.ot locking circuit boards in place

• stressed breaker terminations due to cable routing

• insufficient terminal screw length for 3 lug connections

• loose DC breaker mounting bolts

• bad solder connections for various wires

• frame ground for various components not clean to steel

• terminal strips missing brass cover screw and/or cover rings

• stressed wire terminations due to wire routing

• damaged AC breaker due to stressed terminations NRC FORM 366A (4-95)

• NRC FORM 366A 14*951 U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (6) PAGE (3)

SALEM GENERATING STATION UNIT 2 05000311 YEAR I SEQUENTIAL NUMBER I RE'llSlll NUllllER 3 OF 4 96 - 008 - 00 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

CAUSE OF OCCURRENCE The apparent cause of the discrepancies identified is poor workmanship during manufacturing and shipping damage.

PRIOR SIMILAR OCCURRENCES LER 272/96-009-00, Potential Common Mode Failure for 4KV Magne-Blast Breakers, documented a potential common mode failure due to misalignment of breaker mechanisms and internals that was undetected by the overhaul vendor (Nuclear Logistics Inc.). The corrective actions included correction of the misalignment and revised breaker testing methods.

LER 272/96-014-00, Potential Hydrogen Embrittlement on 4KV Breaker Parts, documents defective parts created by incorrect overhaul practices of a qualified vendor. The corrective actions included refurbishment of affected breakers and a stop work order issued to the overhaul vendor (Nuclear Logistics Inc.).

SAFETY CONSEQUENCES AND IMPLICATIONS The 125V DC battery system for Salem Station Unit 2 consists of three 125V DC battery sets, each of which has a primary and alternate battery charger. Each charger maintains a floating charge on its associated battery, and is capable of supplying the required equalizing charge when necessary. During normal operation, the DC load is fed from the battery chargers with the batteries floating on the system. Upon loss of DC power from a battery charger, the DC load is drawn from the batteries. The batteries are sized for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> of operation after a loss of the battery chargers, based upon required operation of the 125V DC emergency equipment.

The 125V DC busses supply power to the 125V DC Contro.l .. __ :/stem. *. nis ..

system provides power to the medium and high voltage breaker controls; 480V AC pressurizer heater circuit breakers; vital instrument bus inverters; computer inverters, eme~gency lighting inverters; alternate shutdown system; the Diesel Generator 125V DC distribution panel; and various other 125V DC controls and instruments required for safe shutdown of the reactor under transient and accident conditions.

Based on significant roblems identified with all o~ the battery chargers, there was no reasonable assurance that the battery chargers would be operable following a seismic event. For the current defueled condition, the worst case postulated accident is a Loss of Spent Fuel Pool Cooling for Unit 2. Assuming a loss of all Unit 2 primary and backup battery chargers following a seismic event, the two hours of battery capacity provides time to restore vital buses if needed and reestablish spent fuel pool cooling for Unit 2. If spent fuel pool cooling cannot be restored for Unit 2 due to a prolonged inability to repower vital buses, procedures followed during a loss of spent fuel pool cooling allow for the use of the Unit 1 spent fuel pool cooling system in a cross connection with Unit 2. Therefore, the implications for the inoperability of the battery chargers were minimal and thus the health and safety of the public was unaffected.

NRC FORM 366A (4-95)

., NRC FORM 366A (4-95)

U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (6) PAGE (3) 05000311 YEAR I SEQUENTIAL NUMBER I REV1SIOI lllMIER 4 OF 4 SALEM GENERATING STATION UNIT 2 96 - 008 - 00 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

CORRECTIVE ACTIONS

1. The Unit 2 battery chargers will be reworked to design specifications by September 15, 1996.

2. The Unit 1 battery chargers will be reworked to design specifications prior to installation in Unit 1. Testing will follow installation.

3. PSE&G Nuclear Procurement and Materials Management is undertaking an investigation of common cause analysis for procurement concerns identified as a result of LER 272/96-009-00, LER 272/96-014-00, this LER, and a recent 10CFR21 report concerning defects found in NUS logic modules. Further corrective actions will be taken as a result of the evaluation currently being conducted. Significant corrective actions that affect the discussion in this LER, if any, will be reported in a supplement to this LER.

10CFR21 REPORTING 10CFR21 reporting is applicable to the defects found.

NRC FORM 366A (4*95)