ML20045H857

LER 93-008-00:on 930614,one Channel of Electrical Environmentally Qualified Temp Monitor for Main Steam Valve Bldg Found Indicating Improperly.Caused by Personnel Error. Manual Logging of Temp initiated.W/930709 Ltr

ML20045H857
Person / Time
Site:	Millstone
Issue date:	07/09/1993
From:	Scace S, Young J NORTHEAST NUCLEAR ENERGY CO., NORTHEAST UTILITIES
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-93-008-01, LER-93-8-1, MP-93-546, NUDOCS 9307220022
Download: ML20045H857 (4)

Text

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E'ORTNEAST UTILmES oa-=' o"*a saa S-t S""" coana"c"t I W sfeNaYsIchYsItIE e cC pa P.O. box 2'70

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as I((t$iIs$rv ompany HAATFORD, CONNECTtouT 06141-0270 Northeast Nuclear Energy Company (203)S65-5000

.Tuly 9, 1993 MP-93-546 f

Re: 10CFR50.73(a)(2)(i)

U-.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555

Reference:

Facility Operating License No. NPF-49 Docket No. 50-423 Licensee Event Report 93-008-00 Gentlemen:

This letter forwards Licensee Event Report 93-00S-00 required to be submitted within thirty (30) days pursuant to 10CFR50.73(a)(2)(i).

Very truly yours, NORTHEAST NUCLEAR ENERGY COMPAhnf I& mv Step en E. Scace L Vice President - Millstone Station SES/JSY:ljs

Attachment:

LER 93-008-00 l

ec: T. T. Martin, Region I Administrator P. D. Swetland, Senior Resident Inspector, Millstone Unit Nos.1, 2 and 3 V. L. Rooney, NRC Project Manager, Millstone Unit No. 3

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2^' ^9307220022

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PDR ADOCK 05000423 930709 p S PDR p*)q bl[ 070/ $ 5 7$/ ' I

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NRC Form 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED OMB NO. 3150-0104 (6-89)

• EXPIRES: 4/30/92 Estimated burden per response to comply with tn:s

• Information collection teovest: 50.0 hrs. Forward comment egarding buroen estimate to the Records LICENSEE EVENT REPORT (LER) and Repom Management Branch (p-530). U.S Nuclear Regulatory Commission. Washington. DC 20555 and to

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the Paperwork Recuction Project .(3150-0104). Office of Management and B.sopet. Washington, DC 20503 F ACIUTY NAME (1) D00rd.1 NUMi:lER th aM '

Millstone Nuclear Power Station Unit 3 oI sl of of of 41213 1lOFl 0l 3 TITLE tap Main Steam Vahe Buildmg Temperature Monitor Inoperable EVENT DATE IS) LE A NUMBEA r6) AFPORT DATE m OTHER F ACILITIES INVOLVED 18)

MONTE DAY YEAR YEAR n N"  : MONTH DAY YEAR F ACIUTY NAMES 01 si ol of of I l O 6 1l4 9 3 9 l3 0l0l8 0l 0 0 l7 0l9 9l3 ol si al of of l l OPERATING TH!S REPORT IS BEING SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR $. (Check one or more ci tne fobowing)(11)

O # 2k402(b) 20.402tc) 50,73(a)(210v) 73.71(b)

PO ER 20 405(a)(1)U) 50.36tc)(1) 50.73(a)(2)(v) 73.711c) i10, 1l0l0 20 405(*H'100 50.36(c)(2) _

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' Text. NR orm 365A) 20 405ta)(1Hid) g 5033(a)(2)(l) _

50.73(a)(2)(whl)( A) .

20 405(a)(1)Oy) 50.73(aH2)(h) 50.73 t a)(2)(viii)(B) 20 405f al(11riv) 50.73(a)(2104) 50.73 (a)(2)(x) {

LICENSEE CONTACT FoR THfS LER (12)  !

NAME TELEPHONE NUMBER AREA CODt Jeffrey S. Young. Engmeer, Ext. 6442 2]0l3 4l4l7l-l1l7l9l1 COMDLETE ONE LINE FOR E ACH COMPONENT F AILURE DESCRIBED IN THIS REPORT (13)

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ABSTRACT Ilimit to 1400 spa::es. 6 e. , appro(imately frtteen s+ngie-s, ace typewritten hnes) i16)

On June 14,1993, at 1200 with the plant in Mode 1 at 1009, one channel of the Electrical Environmentally Qualified (EEQ) temperature monitor (datalogger) for the Main Steam Valve Building was found to be ,

indicating improperly. The discovery was made by a Plant Equipment Operator (PEO) while on routine rounds.

Further investigation determined that when the datalogger had been upgraded on May 28, 1993, two channels had been assigned to the same detector.

The root cause of this event was personnel error. The technician assisting in the upgrade of the datalogger incorrectly entered part of the software. As a result, two channels were assigned to the same sensor. A line by line review of the software by the vendor and the technician did not detect .he error. Subsequent retest did not detect the error either, despite the fact that a 27 degree Fahrenheit difference existed between "as found" and "as left" data.

The immediate corrective action was to declare the channel inoperable at>d begin logeing temperature manually  !

to satisfy the survei!!ance requirement. l l

As action to prevent recurrence, the technicians and supervisor invohed have been counseled on work control and importance of performing retests. First line supervisor's responsibility for technical review of results of retests has been reinforced.

. NRC Form.366 (6-89)

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NdC Forre 366A

• u.S. NUOLEAR REGULATORY COMM!SSloN APPROVED OMB No. 3150-0104 (6-69) EXPIRES: 4/30/92

, Estimated Durosai per response to comply witn this LICENSEE EVENT REPORT (LER) gm*'g,$*fdg5g,50f,,h'5 n,, m [gg*;d,,,,

1g TEXT CONTINUATION and Rooorts uuegemoni eranen to-s30). u.S Nucisar -

Regulatory Commission, Washington oC 20555, and to the Paperwork Redaction Project (3150-0104 office of Management and Buopet Washington, De 20503.

F AOluTY NAME (1) DQcKET NUMBER (2) (EA NUMBrr. m PAGE f3!

YEAR N N Millstone Nuclear Power Station Unit 3 - -

ol5lololol4l2l3 9l3 0l 0l 8 0l0 0l 2 OF 0l3 TEXT tif more space is required. use add:tional NRc Form 366A's) (17)

1. Descrintion of Event On June 14,1993, at 1200 with the plant in Mode 1 at 100% power (2250 psia and 587 degrees Fahrenheit), one channel of the EEQ temperature monitor (datalogger) for the Main Steam Vahe l Buildmg (MSVB) was found to be indicating the incorrect temperature. The channel was declared - {

inoperable and manual logging of the temperature was started. The discovery was made by a Plant  ;

Equipment Operator during routine rounds.

Subsequent investigation revealed that an upgraded datalogger had been installed under established replacement item evaluation procedures on May 28, 1993 by the Instrument and Controls Department. j Due to incompatibilities between systems, manual entry of the software became necessary; During this process, two channels were inadvertettly assigned to the same detector. A line by line review of the change by the technician and the venc<3r supporting the installation did not detect the error. The technician performing the retest for the upgrade did not detect _ the fact that the "as found" and "as left" data for the inoperable point differed by 27 degrees Fahrenheit.

II. Cause of Event The root cause of this event was personnel error. The technician incorrectly entered the software and did not detect the error during review of the installation. The technician performmg the retest did not adequately compare test results. 4 I

111. Analvcic of Event This event is being reported in accordance with 10CFR50.73(a)(2)(i) as a condition prohibited by ,

Technical Specifications. Surveillance requirement 4.7.14 (Area Temperature Monitoring) as it applies to i the MSVB requires monitoring of temperatures in the MSVB every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> to ensure that they are less than the EEQ limit of 120 degrees Fahrenheit. While four channels were monitoring other parts of the MSVB. the one inoperable channel was in the hottest area. With this channel of the'datalogger inoperable, the requirement was not satisfied fo'r approximately 2 weeks. l The safety significance of this event is minimal. Since all other locations in the MSVB were properly ,

monitored and showed no adverse trends over the 2 week period, it is reasonable to conclude that the j un-monitored area was also acceptable. In addition, PEOs normally tour this area on rounds and would notice any abnormally high temperature. Since no action affecting plant operation is required unless temperatures exceed the limit by more than 20 degrees Fahrenheit and no evidence exists that the limit was approached, it is reasonable to conclude that no action was required for the un-momtored area.

IV. Corrective Action The immediate corrective action was to declare the channel inoperable and initiate manual logging of area temperature in the MSVB and initiate a review of the software in the datalogger The channel was reprogrammed on June 14,1993 and returned to senice.

As action to prevent recurrence, the technicians and the supenisor involved have been counseled on work control and importance of performing retests. First line supervisor's responsibility for technical review of results of retests has been reinforced.

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NRc For+ 366A - '

U S. NUCLEAR REGULATORY COMM3SSION APPROVED OMB NO. 3150-0104 (6-89) EXPIRES. 4/30/92

. Estimated burden per response to comply with this intymaton coliection recuest: 60,0 hrs. Forward LICENSEE EVENT REPORT (LER) Comments regarding burden estimate to tne Records TEXT CONTINUATION and Reports Management eranen to-530). U.S. Nuclear Regulatory Commission. Wasnington. DC 206sS. and to tree Pa:wworu Aeduction Project f3150-0104). Oftco of Management and Buopet. Washington. DC 20503.

FACluTY NAME (1) DOCKET NUMBER (2) t FA NUMBFA #6) PAGE (3)

YEAR N N u sen suam Millstone Nuclear Power Station .

Unit 3 0] 5) 0l 0l 0l4 l2 l3 9l3 0l0l8 0l0 0l 3 OF 0l3 TEXT (11 rnore space is recuned, use addttional NAC Form 366A's) (17)

V. Addnional Information Other Licensee Event Reports (LERs) which have been submitted where personnel error in programming resulted in equipment being inoperable without the knowledge of Control Room staff, LER Number Ilile,89-029 Missed Axial Flux Difference Technical Specification Surveillance Due to Procedural Inadequacy.

LER 89-029 describes an event where a change was made to a subroutine on the process computer. This subroutine was used by several programs including the Axial Flux Difference (AFD) program. However, l no retest was required for the AFD program.' As a result, improper operation of the program was not detected. Corrective action for this event was directed at the Computer Services Department to ensure l l that adequate retests were specified after making software modifications.

Since the current event does not involve the process computer and adequate retests were specified, the corrective action for LER 59-029 would not have prevented the current event.

l Ells codec Sveten.s Comnonent Temperature Monitoring Software System - IM i l

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