Part 21 Report - 1998-141
ACCESSION #: 9802020051
Illinois Power Company
Clinton Power Station
P.O. Box 678
Clinton, IL 61727
Tel 217 935-5623
Fax 217 935-4632
Walter G. MacFarland IV
Chief Nuclear Officer
ILLINOIS
POWER
An Illinova Company U-602920
4F.140
January 28, 1998
Docket No. 50-461 10CFR21.21
Document Control Desk
Nuclear Regulatory Commission
Washington, D.C. 20555
Subject: 10CFR21 Initial Report 21-97-044/047/048:
Deviations in Safety Related Battery Chargers
Dear Madam or Sir:
On December 3, 1997, Illinois Power (IP) issued 10CFR21 Interim
Report 21-97-044/047/048 in letter U-602876 to notify the NRC that an
evaluation under the provisions of 10CFR, Part 21 was not complete for
deviations discovered in safety-related battery chargers. The following
information is a follow-up to the December 3, 1997, letter.
On September 29, 1997, the Division 2 safety-related battery charger
failed to operate as expected. Operators received an alarm in the Main
Control Room indicating low Division 2 Direct Current (DC) bus voltage.
Indications also included zero amps output from the Division 2 battery
charger, and DC bus voltage stabilized at about 128 as Volts Direct
Current (VDC) which is the expected voltage for a loss of the battery
charger. An electrician was dispatched to the Division 2 battery charger
to investigate the problem and noted that the charger appeared to be
stopping and starting itself "electronically"; the DC voltage and output
current decreased to zero and then returned to normal. The self-starting
and stopping of the charger occurred four times over approximately a 30
minute period before the charger was secured for troubleshooting.
On October 4, 1997, as a result of troubleshooting, IP identified
inadequate soldered wire connections throughout the battery charger.
Specific examples include solder connections on the Silicon Controlled
Rectifier (SCR) firing circuit boards and on wiring connections for the
SCR firing circuit. This issue was determined to be potentially
reportable under 10CFR21; Condition Reports (CR) 1-97-10-090, 1-97-10-
123, and 1-97-10-201 were initiated to track the evaluation and
resolution of the inadequate soldered wire connection issues.
U-602920
Page 2
On October 15, 1997, during further troubleshooting, IP noted two
anomalies with the High Voltage Alarm (Shutdown) (DSHV) circuit end. The
time delay for the circuit card was approximately six seconds rather than
30 seconds per the purchase specification, and the reset voltage setpoint
of the DSHV was too low to allow the DSHV circuit card to reset during a
momentary voltage transient while the battery charger was in the equalize
mode. These issues were determined to he potentially reportable under
10CFR21; CR 1-97-10-241 was initiated to track in evaluation and
resolution of the DSHV circuit card issues.
The deviations discussed above are also applicable to the Divisions
1 and 4 safety-related battery chargers, with the exception that no
inadequate solder issues were identified in the Division 4 battery
charger.
The Divisions 1, 2, and 4 safety-related battery chargers are Model
3SC-130-300 supplied by Power Conversion Products, Inc. The DSHV reset
voltage setpoint was provided by Sargent & Lundy.
On January 16, 1998, an evaluation of these issues concluded that
the inadequate soldered wire connection issues did result in a failure of
the Division 2 battery charger while it was performing Its safety
function and caused the Division 2 safety-related battery charger to be
inoperable. Therefore, these issues should be reported under air
provisions of 10CFR50.73.
IP has completed the evaluation of the battery charger deviations
and concludes that these issues should also be reported under the
provisions of 10CFR21. The basis for the reportable conclusion is that
some of the solder issues, and the DSHV time delay and reset voltage
setpoint circuit card issues, were supplier deviations that left
uncorrected could have caused a loss of the safety function of the
Division battery charger.
IP will issue a report of these issues In accordance with the
provisions of 10CFR21 and 10CFR50.73 by February 17, 1998.
IP also reported in the December 3, 1997, letter that, during bench
testing on October 15, 1997, a new DSHV circuit card from stores failed
to provide an output. The DSHV circuit card way being tested prior to
installation to determine its output response time. During the testing,
the trip setpoint voltage was reached and the LED indication illuminated;
however, the DSHV circuit card failed to provide the required output for
the alarm and trip functions. This issue was determined to be
potentially reportable under 10CFR21, and CR 1-97-10-249 was Initiated to
track an evaluation and resolution of the DSHV circuit card that failed
to provide an output, The evaluation of this issue has concluded that the
failure of the DSHV circuit card to provide an output is not reportable
under 10CFR.21. The basis for this conclusion is that the DSHV circuit
card requires calibration prior to installation. Calibration of the DSHV
circuit card revealed the failure of the card to provide an output,
therefore, the failure could not go uncorrected.
U-602920
Page 3
Additional information about these issues may be obtained by
contacting M. D. Wagner, Plant Engineering, at (217) 935-8891,
extension 4071.
Sincerely yours,
Walter G. MacFarland, IV
Chief Nuclear Officer
RSF/krk
cc: NRC Clinton Licensing Project Manager
NRC Resident Office, V-690
Regional Administrator, Region III, USNRC
Illinois Department of Nuclear Safety
INPO Records Center
Power Conversion Products
Sargent & Lundy
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