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 *** END OF DOCUMENT ***

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