ML18102B585

LER 97-010-00:on 970819,position Indication Sys Were Shutdown as Required by Ts.Caused by Deficiencies in Design, Mfg Const/Installation.Successfully Recalibrated Rod Position Indication sys.W/970917 Ltr

ML18102B585
Person / Time
Site:	Salem
Issue date:	09/17/1997
From:	Garchow D, Enrique Villar Public Service Enterprise Group
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-97-010-01, LER-97-10-1, LR-N970585, NUDOCS 9709240049
Download: ML18102B585 (5)

Text

OPS~G Public Service Electric and Gas Company P.O. Box 236 Hancocks Bridge, New Jersey 08038-0236 Nuclear Business Unit

-i**

SEP 17 1997 LR-N970585 U. S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 ~-I,".... .

Gentlemen:

LER 311/97-010-00 SALEM GENERATING STATION - UNIT 1 AND 2 FACILITY OPERATING LICENSE NOS. DPR-70 AND DPR 75 DOCKET NO. 50-272 AND 50-311 This Licensee Event Report entitled ~Technical Specification Required Shutdown - Position Indication Systems" is being submitted pursuant to the requirements of the Code of Federal Regulations 10CFR50. 73 (a) (2) (i).

([OF.el~

David ~archow General Manager -

Salem Operations Attachment EHV/tcp C Distribution LER File 3.7 9709240049 970917 PDR ADOCK 05000272 S PDR 111111111111111111111111111111111111 llll The power is in your hands.

• 986151*

__ .1 95-2168 REV. 6/94

FORM 366 U.S. NUCLEA REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104

) 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 LICENSEE EVENT REPORT (LER) LICENSING PROCESS AND FED BACK TO INDUSTRY.

COMMENTS REGARDING BURDEN ESTIMATE TO THE INFORMATION FORWARD AND RECORDS MANAGEMENT BRANCH (T-6 F33J, U.S. NUCLEAR (See reverse for required number of REGULATORY-COMMISSIONT WASHINGTON, DC 20 55-0001, AND TO THE PAPERWORK REDUC ION PROJECT 63150-0104), OFFICE OF digits/characters for each block) MANAGEMENT AND BUDGET, WASHINGTON, C 20503.

CILITY NAME (1) DOCKET NUMBER (2) PAGE(3)

?ALEM GENERATING STATION UNIT 2 05000311 1 of4 rLE (4)

ECHNICAL SPECIFICATION REQUIRED SHUTDOWN - POSITION INDICATION SYSTEMS EVENT DATE (5) LER NUMBER (6) REPORT DATE (7) OTHER FACILITIES INVOLVED (8)

FACILITY NAME DOCKET NUMBER 10NTH DAY YEAR SEQUENTIAL I REVISION MONTH DAY YEAR YEAR I NUMBER NUMBER Salem Generating Station Unit 1 05000272 r.1

___fli ..

8 19 97 97 010 - 00 09 17 97 FACILITY NAME DOCKET NUMBER 05000 OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check one or more) (11)

MODE (9) 20.2201(b) 20.2203(a)(2)(v) x 50. 73(a)(2)(i) 50. 73(a)(2)(viii)

POWER 20.2203(a)(1) 20.2203(a)(3)(i) 50. 73(a)(2)(ii) 50. 73(a)(2)(x)

LEVEL (10) 20.2203(a)(2)(i) 20.2203(a)(3)(ii) 50. 73(a)(2)(iii) 73.71 20.2203(a)(2)(ii) 20.2203(a)(4) 50. 73(a)(2)(iv) OTHER

• • r~11~~? lt 7 20.2203(a)(2)(iii) 50.36(c)(1) 50. 73(a)(2)(v) Spec~in Abstract below or in C Form 366A

- - u 20.2203(a)(2)(iv) 50.36(c)(2) 50. 73(a)(2)(vii)

LICENSEE CONTACT FOR THIS LER (12)

>.ME TELEPHONE NUMBER (Include Area Code)

. H. Villar, Station Licensing Engineer (609) 339-5456 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

Kl -

~l CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TONPRDS TONPRDS SUPPLEMENTAL REPORT EXPECTED (14) 11 EXPECTED SUBMISSION MONTH DAY YEAR IYES (If yes, complete EXPECTED SUBMISSION DATE). x1NO DATE (15)

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

On August 18, 1997, during performance of low power reactor physics testing, two analog rod position indicators showed two rods deviating by more than 12 steps from their group demand counter. Technical Specification action statement 3.1.3.2.l b was entered at 2238 hours0.0259 days <br />0.622 hours <br />0.0037 weeks <br />8.51559e-4 months <br />. On August 19, 1997, at 0005 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> control room operators initiated a plant shutdown to comply with the requirements of the Technical Specifications, and at 0024 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> completed the shutdown by entering {Mode 3) where the Specification is no longer applicable.

The apparent cause of this event has been attributed to Deficiencies in Design, Manufacturing Construction/Installation.

Corrective action taken was the successful ~ecalibration of the rod position indication system. A long term corrective action taken was the submittal of a license change request to increase the allowable.rod deviation to+/- 18 steps (power dependent) .

This condition is being reported in accordance with 10CFRS0.73 (a) ( 2) (I) .

A one hour report was made in accordance with 10CFRS0.72 on August 19, 1997.

IRC 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)

YEAR SEQUENTIAL REVISION 05000311 NUMBER NUMBER 2 OF 4 SALEM GENERATING STATION UNIT 2 97 - 010 00 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

PLANT AND SYSTEM IDENTIFICATION Westinghouse - Pressurized Water Reactor Rod Position Indication System (RPIS) {AA}*

• Energy Industry Identification System (EIIS) codes and component function identifier codes appear in the text as {SS/CCC}.

IDENTIFICATION OF OCCURRENCE Date Determined to be Reportable: August 19, 1997.

CONDITIONS PRIOR TO OCCURRENCE Unit 1: Defueled, O % Reactor Power Unit 2: Mode 2, O % Reactor Power There were no structures, components, or systems that were inoperable at the start of the eve.nt that contributed to the event.

DESCRIPTION OF OCCURRENCE On August 18, 1997 during the performance of reactor physics testing for control rod swaps, two control bank D rods were noted to deviate by more than 12 steps from their group demand counter. Technical Specifications 3.1.3.2.1 Action b was entered at 2238 hours0.0259 days <br />0.622 hours <br />0.0037 weeks <br />8.51559e-4 months <br />, following the one hour thermal soak allowed by the Technical Specifications Limiting Condition for Operation. Technical Specification 3.1.3.2.1 Action b states, in part; "With two or more analog rod position indicators per bank inoperable, within oGe hour restore the inoperable rod position indicator(s) to OPERABLE status or be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> ... "

As a result of the reactor being operated at approximately 2% Rated Thermal Power, the available neutron flux was not sufficient to perform a flux map to determine the actual position of these rods. Therefore, on August 19, 1997 at 0005 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> control room personnel initiated a reactor shutdown to Hot Standby, in accordance with the applicable Technical Specifications requirements.

NRC FORM.366A (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) 05.000311 YEAR I SEQUENTIAL NUMBER IREVISION NUMBER 3 OF 4 SALEM GENERATING STATION UNIT 2 97 - 010 - 00 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

DESCRIPTION OF OCCURRENCE {cont'd)

The shutdown was completed at 0024 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, when the Unit was placed in a non applicable Mode (Hot Standby) .

SAFETY SIGNIFICANCE There was no safety significance associated with this event. The control rods were declared inoperable due to a mismatch between their demanded vs.

indicated position. However, the control rods were always capable of performing their safety function, which is to rapidly insert negative reactivity (fall) into the core following a loss power.

APPARENT CAUSE OF OCCURRENCE The apparent cause of this event has been attributed to Deficiencies in Design, Manufacturing Construction/Installation.

Rod position is determined by use of a linear voltage transformer

• consisting of a primary and secondary coils alternately stacked on the steel support tube. This method of determining Rod Position Indication has experienced some difficulties with the calibration technique. Some of the basic problems encountered with calibrating the system are associated with; *

1. The instrumentation readout design is based on the assumption that secondary voltage is a linear function of rod position. In fact, the steady-state calibration curve is more of an arc-shaped or even an S-shaped curve such that for some rods the steady-state Zero Span adjustment may not always be able to be calibrated to within the +/- 12 steps, and

2. The instrument response is highly dependent on temperature changes, such as Reactor Coolant System temperature changes and t_~mperature changes associated with rod motion itself. This 11 transient 11 thermal response has been categorized as 11 overshoot, 11 and this transient indication error tends to be worse near the top of the core (rods wi~hdrawn) .

NRC FORM 366A (4-95)

NRC FORM 366A (4-95)

• LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION U.S. NUCLEAR REGULATORY COMMISSION FACILITY NAME (1) DOCKET NUMBER (2) LER NUMBER (6) PAGE (3) 05000311 YEAR I SEQUENTIAL NUMBER IREVISION NUMBER 4 OF 4 SALEM GENERATING STATION UNIT 2 00 97 - 010 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

PRIOR SIMILAR OCCURRENCES Salem Units 1 and 2 have been shutdown since May and June 1995, respectively. There are no prior similar occurrences which have been identified within the past two years. However the following LERs have been identified as having been submitted in the past 3 years, prior to Amendment 166/148 issued May 3, 1995; (1) Associated with docket No. 50-272;94-004, 94-006,94-010, 94-012,94-014, and.95-003, (2) Associated with docket No 50-311;94-001, 94-003,94-009, and 95-002.

Amendment 166/148 modified Technical Specification 3.1.3.2.1 Action b, such that the loss of indication of more than one position indicators would not result in an automatic 3.0.3 entry by providing the operators with the same action time under the limiting Condition for Operation Action Statement.

CORRECTIVE ACTIONS

1. On August 19, 1997, at 0005 hrs a Unit shutdown was initiated in accordance with Technical Specifications 3.L3.2;1 Action b, and was completed at 0024 hrs on August 19, 1997.

2. The analog rod position indication system was successfully recalibrated.

3. A license change request has been submitted to expand the allowable deviation between demanded and indicated position from +/- 12 steps to +/- 18 steps (power dependent) .

4. Individual rod position scaiing have been provided for each rod and have been applied to the position indication provided by the Plant Computer (P-250) .

NRC FORM 366A (4*95)