Protecting People and the EnvironmentUNITED STATES NUCLEAR REGULATORY COMMISSION
ACCESSION #: 9609100105
LICENSEE EVENT REPORT (LER)
FACILITY NAME: SALEM GENERATING STATION UNIT 2 PAGE: 1 OF 4
DOCKET NUMBER: 05000311
TITLE: Inoperable Battery Chargers Due To Manufacturing
Discrepancies
EVENT DATE: 07/29/96 LER #: 96-008-00 REPORT DATE: 08/24/96
OTHER FACILITIES INVOLVED: Salem Unit 1 DOCKET NO: 05000272
OPERATING MODE: N POWER LEVEL: 000
THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR
SECTION:
50.73(a)(2)(iv)
50.73(a)(2)(vii)
OTHER: Part 21
LICENSEE CONTACT FOR THIS LER:
NAME: Dennis V. Hassler, LER Coordinator TELEPHONE: (609)-339-1989
COMPONENT FAILURE DESCRIPTION:
CAUSE: B SYSTEM: EJ COMPONENT: BYC MANUFACTURER: C127
REPORTABLE NPRDS: Y
SUPPLEMENTAL REPORT EXPECTED: NO
ABSTRACT:
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 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 discrepancies.
The apparent cause of the discrepancies identified is poor workmanship
during manufacturing and shipping 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), 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).
END OF ABSTRACT
TEXT PAGE 2 OF 4
PLANT AND SYSTEM IDENTIFICATION
Westinghouse - Pressurized Water Reactor
125 VDC Power System - Class 1E/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 discrepancies since the Unit 1 chargers are a
different design.
The discrepancies listed below represent a general list of manufacturing
deficiencies found in these safety related pieces of equipment:
o broken welded mounting brackets for the filter choke and DC
Capacitor assembly
o loose and/or missing mounting bolts on the transformers
o strands of wires not properly soldered
o loose wire terminations
o plastic lock-in standoff tabs broken and not locking circuit
boards in place
o stressed breaker terminations due to cable routing
o insufficient terminal screw length for 3 lug connections
o loose DC breaker mounting bolts
o bad solder connections for various wires
o frame ground for various components not clean to steel
o terminal strips missing brass cover screw and/or cover rings
o stressed wire terminations due to wire routing
o damaged AC breaker due to stressed terminations
TEXT PAGE 3 OF 4
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 hours 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 Control Power System.
This system provides power to the medium and high voltage breaker
controls; 480V AC pressurizer heater circuit breakers; vital instrument
bus inverters; computer inverters, emergency 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 problems identified with all of 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.
TEXT PAGE 4 OF 4
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.
ATTACHMENT TO 9609100105 PAGE 1 OF 2
PSE&G
Public Service Electric and Gas Company P.O. Box 236 Hancocks Bridge,
New Jersey 08038-0236
Nuclear Business Unit
AUG 24 1996
LR-N96265
U. S. Nuclear Regulatory Commission
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).
Sincerely,
David F. [illegible print]
General Manager
Salem Operations
Attachment
SORC Mtg. 96-114
JMO/tcp
C Distribution
LER File 3.7
The power is in your hands.
95-2168 REV. 6/94
ATTACHMENT TO 9609100105 PAGE 2 OF 2
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 272/96-00900, 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.
*** END OF DOCUMENT ***
