ML19340C473

LER 80-088/03L-0:on 801017,reactor Power Was Increased to 52.1% as Determined by Calorimetric Test.Caused by Change in Reactor Power Between Time Nuclear Instrumentations Were Set & Time Next Calorimetric Test Performed.Power Reduced

ML19340C473
Person / Time
Site:	North Anna
Issue date:	11/10/1980
From:	Cartwright W VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19340C469	List: ML19340C468 ML19340C473
References
LER-80-088-03L, LER-80-88-3L, NUDOCS 8011170458
Download: ML19340C473 (2)

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U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT CONTROL BLOCK / / / / / / / (1) (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)

/0/1/ /V/A/N/A/S/1/ (2) /0/0/-/0/0/0/0/0/-/0/0/ (3) /4/1/1/1/1 (4) / / / (5)

, LICENSEE CODE LICENSE NUMBER LICENSE TYPE CAT

/0/1/ /L/ (6) /0/5/0/0/0/3/3/8/ (7) /1/0/1/7/8/0/ (8) /1/1/1/ o/ a/o/ (9)

~ E DOCKET NUMBER EVENT DATE REPORT DATE EVENT DESCRIPTION AND PROBABLE CONSEQUENCES (10)

/0/2/ / While operating under a limiting condition of T.S. 3.2.1, which specifies that /

/0/3/ / re ctor power shall not exceed 50% if the axial flux difference has been out- /

/0/4/ /, side the 15% target band for > 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> in the past 24 hrs. , reactor power was /

/0/5/ / increased to 52.1% as determined by a calorimetric test. Since power was /

/0/6/ / imnediately reduced below 50%, the health and safety of the public were not /

/0/7/ / affected. Reportable pursuant to T.S. 6.9.1.9.b. /

/0/8/ / /

SYSTEM CAUSE CAUSE COMP. VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE

/0/9/ /R/C/ (11) /X/ (12) /Z/ (13) /I/N/S/T/R/U/ (14) g/ (15)

/_Z/ (16)

SEQUENTIAL OCCURRENCE REPORT REVISION LER/R0 EVENT YEAR REPORT NO. CODE TYPE NO.

(17) REPORT NUMBER /8/0/ /-/ /0/8/8/ /\/ /0/3/ /L/ /-/_ /0/

ACTION FUTURE EFFECT SHUTDOWN ATTACHMENT NPRD-4 PRIME COMP. COMPONENT TAKEN ACTION ON PLANT METHOD HOURS SUBMITTED FORM SUB. SUPPLIER MANUFACTLTER

/E/ (18) /Z/ (19) /Z/ (20) /Z/ (21) /0/0/0/0/ (22) g/ (23) /N/ (24) /N/ (25) /W/1/2/0/ (26)

CAUSE DESCRIPTION AND CORRECTIVE ACTIONS (27)

/1/0/ / The discrepancy between the power range nuclear instrumentation indications /

/1/1/ / and the calorimetric test is attributed to the change in reactor power between /

/1/2/ / the time the NI's were set to 25% power at 1545 on 10-16-80 and the time of /

/1/3/ / the next calorimetric test performed at 1030 on 10-17-80. The corrective /

/1/4/ / action was to reduce power and adjust the NI's. /

FACILITY METHOD OF STATUS  % POWER OTHER STATUS DISCOVERY DISCOVERY DESCRIPTION (32)

/1/5/ /E/ (28) /0/5/2/ (29) /' NA / (30) /B/ (31) / NA /

ACTIVITY CONTENT RELEASED OF RELEASE AMOUNT OF ACTIVITY (35) LOCATION OF RELEASE (36)

'/1/6/ /Z/ (33) /Z/ (34) / NA / / NA /

PERSONNEL EXPOSURES NUMBER TYPE DESCRIPTION (39)

/1/7/ /0/0/0/ (37) /Z/ (38) / NA /

PERSONNEL INJURIES NUMBER DESCRIPTION (41)

/1/8/ /0/0/0/ (40) / NA /

LOSS TYPE OF OR DAMAGE TO FACILITY (43)

DESCRIPTION

/1/9/ /Z/ (42). / NA /

PUBLICITY ISSUED DESCRIPTION (45) NRC USE ONLY

/2/0/ /N/ (44) / NA /////////////

NAME OF PREPARER W. R. CARTWRIGHT PHONE (703) 894-5151

'8011 17 u 93 g

Virginia Electric and Power Company North Anna Power Station, Unit 1

Attachment:

" age 1 of 1 Docket No. 50-338 Report No. LER 80-088/03L-0 Description of Event .

While operating under a limiting condition of T.S. 3.2.1, which specifies that reactor power shall not exceed 50% if the axial flux ,

differeace has been outside the 15% target band for > 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> in the past 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, reactor power was increased from 30% to 46% as indicated by the excore ' nuclear instrumentation. A calorimetric test was subsequently performeJ which revealed reactor power to be 52.1%.

Probable Consequences of Occurrence Since power was immediately reduced below 50%, the health and safety of the public were not affected.

Cause~of Event The discrepancy between the power range nuclear instrumentation and the power level indicated by the calorimetric test is attributed to the 4

change in reactor power between the time the power range instrumentation was adjusted at 23.5% power at 1545 on 10-16-80 and the time of the next calorimetric test performed at 10?J on 10-17-80. The power range instru-mentation requires readjustment aen reactor power changes. Calibration of the NI's is performed on a d ib basis as part of the daily calorimetric test, and also during power ascenuton, at 90%, and 100% reactor power.

Immediate Corrective Action The-corrective action was to reduce power and adjust the voltage on the nuclear instrumentation.

Scheduled Corrective Action No further actions are scheduled.

Actions Taken to Prevent Reccurrence No further action is. required.

Generic Implications There are no generic implicati>ns.