United States Nuclear Regulatory Commission - Protecting People and the Environment

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



An Illinova Company                     U-602920


                                        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.


                                                  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


     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.


                                                  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


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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