ML18152B081

LER 88-026-00:on 880714,inoperable Individual Rod Position Indicators (Irpi) Noted.Caused by Instrument Drift.Affected Irpis Adjusted to Required Tech Spec tolerance.W/880808 Ltr

ML18152B081
Person / Time
Site:	Surry
Issue date:	08/08/1988
From:	Benson D VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
88-037, 88-37, LER-88-026, LER-88-26, NUDOCS 8808190007
Download: ML18152B081 (4)

Text

NRC Form'366 (9-83) e POW 28-06-01 U.S. NUCLEAR REGULATORY COMMISSION APPROVED 0MB NO. 3160-0104

• LICENSEE EVENT REPORT (LER) EXPIRES: 8/31/88 FACILITY NAME 111 DOCKET NU-MBER 121 I PAGE 131 Surrv Power Station Unit 1 Io 1s101010121s 10 ilqF nl ~

TITLE (4)

Inoperable Individual Rod Position Indicators Due To Instrument Drift EVENT DATE (51 LER NUMBER 161 REPORT DATE (71 OTHER FACILITIES INVOLVED 18)

MONTH DAV VEAR VEAR tit sEz~~~~~AL Jt ~~~~~ MONTH DAV YEAR FACILITY NAMES DOCKET NUMBER(S) oI 7 1 I 4 a a - a I a - o I2 I6 - o lo o Is o Is sl s OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check on* or mor* of th* fol/OV(lng} 1111 MODE 191 N 20.4021b) 20.405lcl 60.73(al(2lllvl 73.71lbl POWER LEVEL I -

20.4061*111 llil

- 60.36lcll11

- 60.73lal(21M

..__ 73.711c) 1101

• nl nl n 20.4051all1 l(ill

-x... 50.36lcl(21

- 60.73(al(2Jlvll)

..__ 0TH ER (Specify in Abstr*ct b*low ond In T*xt, NRC Form 1111111=

20.405la)l1 l(ilil 50.73lal(21111 60.73lall2Jlv111JIAI 366A}

20.4051all1 l(lvl 20.405lall1 llvl

- 60.731al(21(1iJ 60.73lal(2lliiil

- 60.73lall21(vlllllBI 60.73lall2Jlxl LICENSEE CONTACT FOR THIS LER 112)

NAME TELEPHONE NUMBER AREA CODE D. L. Benson, Station Manager - 81 0 I 4 31 5 I 71 -1 311 I 81 4 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT 1131 CAUSE SYSTEM COMPONENT MANUFAC- MANUFAC-TURER TURER X AI A 71 I I I M I nI ~ I i. N I I I I I I I I I I I I I I I I I I I I I SUPPLEMENTAL REPORT EXPECTED 114) MONTH DAV YEAR EXPECTED

~

SUBMISSION I YES (If y*s, compl*t* EXPECTED SUBMISSION DA TEI NO DATE 1151 I I I ABSTRACT (Limit to 1400 spec*s, i.*.. *pproxim*t*ly flft*on tingl*-spec* typ*writttJn I/nos/ 1161 On two separate occasions, July 14, 1988 and July 15, 1988, during low power physics testing on.unit 1 with the reactor critical, more than one Individual Rod Position Indicator (IRPI) per group were observed to differ from the step demand counter by more than 12 steps. These events are contrary to T. s. 3.12.E. In both cases, the affected IRPis were adjusted to read within the required Technical Specification tolerance within 30 minutes. Incorrect IRPI indication due to primary temperature changes is known to be a generic Westinghouse concern. A Technical Specification change is being prepared which will accommodate this phenomenon and the P-250 process computer alarm setpoint has been changed to alert the operator when IRPis are 10 steps out of alignment.

88():31,;_;)(>0<">7 r

d~0808 F*,..1R Arro_ c*.*L_'_ - I:" -

S-. .I.' r 0-..,0002:;in PD,::*

NRC Form 366

___LQ.lt3.l - - - -

j;. r--------------111 NRC Fo- 366A

.. -*. .;,; *.~.. '* ..

POW 28-06-()1 U.S. NUCLEAR REGULATORY COMMISSION (9-831 LICENSEE EVENT REPORT (LER) TEXT CONTINUATION APPROVED QMB NO. 3150-0104 EXPIRES: B/31 /88 I FACILITY NAME (1) DOCKET NUMBER 12) LER NUMBER 161 PAGE 13)

Surry Power Station, Unit .1 01s101010121s10 818 -01216 - 010 01 ~oF Ol3 TEXT /If mon, 6psce is required, use additions/ NRC Form 366A's/ 117) 1.0 Description of the Event On two separate occasions, July 14, 1988 at 1654 hours0.0191 days <br />0.459 hours <br />0.00273 weeks <br />6.29347e-4 months <br /> and July 15, 1988 at 0900 hours0.0104 days <br />0.25 hours <br />0.00149 weeks <br />3.4245e-4 months <br />, during low power physics testing on unit 1 with the reactor critical*,

more than one Individual Rod Position Indicator (IRPI)

{EIIS-ZI} per group were observed to differ from the step demand counter by more than 12 steps. These events are contrary to Technical Specification (T. S.)

3.12.E.

For the July 14, 1988 event, two IRPis were affected and reactor power was 5 x lOE-10 amps on the intermediate range. For the July 15, 1988 event, five IRPis were affected and reactor power was 1 x lOE-7 amps on the intermediate range.

In both cases, the affected IRPis were adjusted to read within the required T. s. tolerance within 30 minutes.

2.0 Safety Consequences and Implications The IRPis provide control rod position indication in the main control room. The control rod demand counters, which indicate the control rod group position as demanded by the rod control system, {EIIS-AA}

remained operable during the time the IRPis were not operable.

In addition, inoperable IRPis will not affect the operation of the control rod assemblies. All rods were capable of being dropped into the core if required.

Therefore, the health and safety of.the public were not affected.

3.0 Cause The cause of the event is due to the drift in IRPI indication as a result. of primary coolant temperature changes. This is known to be a generic Westinghouse PWR concern.

4.0 Immediate Corrective Action(s)

The IRPis were adjusted to within the required T. s. tolerance.

NRC FORM 366A *u.s. GPO, 1988-520-589100070 19-83)

POW 28-06-01

_.. NRC Form 366A U.S. NUCLEAR REGULATORY COMMISSION (9-831

• LICENSEE EVENT REPORT (LER) TEXT CONTINUATION APPROVED 0MB NO. 3150--0104 EXPIRES: 8/31/88 I FACILITY NAME (1) DOCKET NUMBER (2) LEA NUMBER (6) . PAGE (3)

Surry Power Station, Unit 1 0 1s IO I O IO I 21*810 8I 8 - 0 I2I6 - 0 I O OI 3 OF O 13 TEXT (ff more space is required, U/S8 11ddition11/ NRC Form 366A 's} (171 5.0 Additional Corrective Action(s)

None required.

6.0 Action(s) Taken to Prevent Recurrence A setpoint change has been made which lowered the P-250 process computer rod deviation alarm to alert the operator.when the IRPis deviate from the group demand position by 10 steps~ This will aid in initiating corrective action prior to exceeding the T. s. limits.

A Technical Specification change is being prepared which will accommodate the effects of primary coolant temperature changes on the IRPis. Until the T. S.

change is approved, the IRPis will be adjusted to agree with the step demand counters as required during primary temperature changes.

7.0 Similar Events Ul LERs: 88-024, 88-010,88-006, 88-002,86-021,85-019.

U2 LERs: 88-012, 88-007,88-003, 86-019,85-009.

8.0 Manufacturer/Model Number Magnetics Inc./Project #K9391, K9392.

NRC FORM 366A *U.S. GPO, 1988-520-589100070 (9-83i

VIRGINIA ELECTRIC AND POWER COMPANY Surry Power Station P. 0. Box 316 Surry, Virginia 23883 August 8, 1988 U.S. Nuclear Regulatory Commission Serial Bo. : 88-037 Document Control Desk

• Docket :No. : 50-280 016. Phillips Building Licensee :No. : DPR-32 Washington, D.C. 20555 Gentlemen:

Pursuant to Surry Power Station Technical Specifications, Virginia Electric and Power Company hereby submits the following Licensee Event Report for Surry Unit 1.

REPORT NUMBER 88-026-00 This report has been reviewed by the Station Nuclear Safety and Operating Committee and will be reviewed by Safety Evaluation and Control.

Very truly yours, V f ml/,

~,ff~ L. Benson Station Manager Enclosure cc: Dr. J. :Nelson Grace Regional Administrator Suite 2900 101 Marietta Street, NW Atlanta, Georgia 30323