ML20042E156

LER 90-003-00:on 900307,individual Cell Voltage for Cell 53 Found to Be at 2.11 Volts,Contrary to Tech Spec Limit.Caused by Electrician Using Improper Acceptance Criteria Format & Inadequate Mgt Review of surveillance.W/900406 Ltr

ML20042E156
Person / Time
Site:	Byron
Issue date:	04/06/1990
From:	Pleniewicz R, Schrock J COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
90-0351, 90-351, LER-90-003-07, LER-90-3-7, NUDOCS 9004200283
Download: ML20042E156 (5)

Text

_

^ Commonwoahh Edison

/ j ByronNuclearStation i j ' 4450 NorthC:rman Church Road

• • ,\ Byron, Illinois 61010 ms I

April 6, 1990 Ltrl BYRON 90-0351  !

I U. S. Nuclear Regulatory Commission 5

Document Control Desk washington, D.C. 20555 j t

i Dear Sirt i 1

The enclosed Licensee Event Report from Byron Generating Station is being '

transmitted to you in accordance with the requirements of 10CTR50.73(a)(2)(1).

This report is number 90-003; Docket No. 50-454.

?

Sincerely,  ;

t

/

R. Pleniewicz / -

Station Manager g/

I Byron Nuclear Powet Station =

l

\

l- RP/dm Enclosures Licensee Event Report No.90-003 cc A. Bert Davis, NRC itegion III Administrator l W. Kropp, NRC Senior Resident Inspector l It4PO Record Center [

CECO Distribution List i

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9004200283 900406 PDR ADOCK 05000454 ,

S PDC l

(0553R/0065R) Ik I

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tlCCC$tt CV[NT R[p0RT (LER)

• facilityName21) Docket Number (2) Pace (3)

Bytan. Unit 1 Of El 01 01 01 41 51 4 1lefl0l4 Title (4)

Mebb e t LER Number (6)

Other Facilities Involved (B) 1YtAL.lt.le ($1 Rttert Date (7)

Month Day Year Year ///

fff Sequential ///j ff Revision Month Oay Year la.cl11tv.Natts J 2tte Lfkehtt(s. L _

/// Number /// Numler NONE _01ELDLOLoJ_1 L

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01 3 01 7 91 0 9l 0 ~'.31013 01 0 0l4 0l 6 9] 0. 01 51 01 01 Ol I L THl$ REPORT l$ $UBMITTED PUR$VANT TO THE REQVIREHENi$ OF 10CIR MERATING

((htik one er meed of the followino) f11) 1 20.402(b) 20.40$(c) 50.73(a)(2)(iv) 73.71(b)

POWER _ 20.405(a)(1)(1) _ 50.36(c)(1) 50.73(a)(2)(v) 73.71(c)

LCVtl 20.405(a)(1)(11) __ 50.36(c)(2) _ 50.73(a)(2)(vii) Other ($pecify (101 4 8 20.40$(a)(1)(Iti) .)L. 50.73(a)(2)(1) 50.73(a)(2)(viii)(A) in Abstract

/ / /// / /,// //, /,// / /,/,/ / /,/ / / / / / 20.405(a)(1)(iv) 50.73(a)(2)(ll) _, 50.73(a)(2)(viii)(B) below and in

//////j////',////}/}///}///////

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j ,_ 20.405(a)(1)(v) _ 50.73(a)(2)(iii) 50.73(a)(2)(r) text)

LICEN$tt CONTACT FOR THl$ LER (12)

Name TELEPHONE NUMBER AREA Coot

.A._hhtnkapeutinnlnninter h b._2116 81 1 I k_ IL.}314 I -LELaL4U c0MPLETE ONE LINE FOR EACH COM 0 FAILURE DESCRIBiD IN THli REPORT (131 CAV$t $Y$ftM COMPONENT MANUFAC- REPORTABLE CAU$E $YSTCH COMPONENT MANUFAC- REPORTABLE TURER TO NPRD$ 11LPER TO NPRDS I _] l 1 1_ l I i j I 1. I I I I l l l 1 1 I I l l l l l l SUPPLEMENTAL REPORT EXPECTED (14) tapected tionth l Day I Ytat Submi sion

}1tl._UL3ts. eemel ietEXPECTED $UBlinHQRJATE) X l NO Date (15)  ; lg ll AB$iRACI (Limit to 1400 spaces, i.e. approximately fif teen single-space typewritten lines) (16)

, On March 7,1990, while reviewing IDHS 8.2.1.2.b-1, "125 Volt Battery Bank Quarterly (Mvision 111) $urveillance".

(performed on 01/23/90) for system trending purposes, the individual cell voltage fe' eell *53 was found to be at

( 2.11 volts. This value is below the Technical Specification limit of }. 2.13 volts t t greater than the allowable l value of > 2,07 volts. The cell voltage was trenediately rechecked and confirmed * ~ ee low. The Division 111 f attery Bus was declared inoperable and timiting Condition for Operation Action krquirement (LC0AR) 100$ 8.2.1-la l was entered.

l l The root cause of this event is two fold. The electrician performing the surveillance did not correctly interpret

( the acceptance criteria stated in the surveillance due to improper acceptance criteria format. the acceptance criteria was in the form of a table instead of comparing As Found data with numerical setpoints noted as ccceptoce criteria. In addition, a management review of the surveillance proved inadequate due to lack of attention to detail combined with the improper acceptante criteria format.

Corrective actions include procedure revisions to clarify the surveillance requirements.

This event is reportable pursuant to 10CFR50.73 (a)(2)(1)(B) for operation prohibited by the plant's Technical Specifications.

(0553R/0065R)

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LIEEN$ft EVENT REPORT (LER) TEXT CONTINUATION Form Rev 2.0 FACILITY NAML (1)

DOCKET NUMBER (2) LER NUPSER (6) Pegt J 1 e Year Sequential

/// /// Revision fff fff

/// Number /// Number h ton. Unit 1 0 i L l 01010141 $14 910 - 01013 - 0I O 01 2 Or _nL4 TEXT Energy Industry Identification System (E!!$) codes are identifled in the text as (XX)

A. PLANT CONDITIONS PRIOR TO EVENT:

Ever.t Date/ Time 03/07/90 / 1445

• Unit 1 MODE _1._ - Power Operation Rx Power 481,_ RCS (AB) Temperature / Pressure yormal Operatina Unit 2 MODE 1 - power Ocaration __ Rx Power 81% RC$ (AB) Temperature / Pressure Normal Operatina._

B. QUERIPTION OF EVENT On 3/7/90, while reviewing 1BHS B.2.1.2.b-1, "125 Volt Battery Bank Quarterly (Division 111) Surveillance" ,

(performed on 1/23/90) for system trending data, the individual cell voltage for cell #53 was found to be at 2.11 volts. This value is below the Technical Specification limit of 12.13 volts but greater than the allowable value of > 2.07 volts. The cell voltage was immediately rechecked and found to be 2.095 volts.

This was less than the minimum 2.13 volts and therefore the Division 111 Battery Bus was declared ,

inoperable and Limiting CondItlon for Operation Action Requirement (LC0AR) 180$ 8.2.1-la was entered. NWR B74716 was written to place a single cell charger on the affected cell to restore the voltage to >2.13 volts.

No plant systems or components were previously (noperable that contributed to this event. No operator actions were taken which either increased or decreased the severity of this event. No safety system j actuations occurred during this event.

, $1nce the inoperability of the battery can be traced to the executed surveillance, the LC0AR should have l been entered on 1/23/90 which requires the parameter to be restored within 7 days. This event is .,

l reportable per 10CRF$0.73(a)(2)(1)(B) for an operation or condition prohibited by the plant's Technical Specifications.

C. (& $E OF EVENT:

The cause of this event is two-fold. The electrician performing the surveillance did not correctly interpret the acceptance criteria stated in the surveillance. In addition, a management review of the surveillance f ailed to identify the low cell voltage.

l The root cause of the electrician (non-licensed) not realizing the cell voltage was below its acceptance ,

criteria was due to confusion in reading the Battery Surveillance Requirements provided in the surveillance l due to improper acceptance criteria format.

Currently the acceptance criteria in the surveillance is listed in the form of a table which is a subset of '

l the table and notes appearing in Techt.ical Specifications. This table is divided into two categories l relating to the battery parameters, one category listing the minimum " LIMITS FOR EACH CONNECTED CELL" and a ,-

second category listing the minimum " ALLOWABLE VALUE FOR EACH CONNECTED CELL". The individual performing the surveillance incorrectly read the table believing the battery was operable provided each connected cell was within its ALLOWABLE value even though the cell voltage was less than its LIMIT. - However, per a note explaining the LIMIT parameters, the actual requirement is that the battery may only be considered operable provided the voltage is restored to within its LIMITS within seven days. This note did not explicitly require a LC0AR entry. Therefore, believing the voltage was within its acceptance criteria, the -

appropriate personnel were not notified.

(0$$3R/0065R) t f

LICENSLE EVENT REPORT (LER) TEXT CONTINUATION form Rev 2.0

, FACILITY NAME (1) 00CKE1 NUPeER (3) . LEll nut 9ER (6) Page (3)

• Year Sequential Revision

///

/// Number

(//

///

f Number. l Byron. Unit 1 0 1 5 1 0 1 0 1 0 1 41 51 4 910 - Ol013 - 01 0 01 3 0F 01 4 TEXT Energy Industry Identification System (E!!$) codes are identifled in the text as [XX) l The root cause of the (Ladequate management review of the completed surveillance was due to cognitive personne' error because the people performing the review did not recognize the low voltage condition.

Contributing to the inadeovate review was the procedure format which did not clearly state the acceptance criteria and compare the Technical Specification values to surveillance data.

The surveillance was signed complete by the electrician at 1430, on 1/23/90, as documented on the "

, surveillance data package cover sheet. The Electrical Maintenance Foreman (non-licensed) completed the surveillance sunnary checklist on the surveillance cover sheet at 1435, on 1/23/90. The Foreman Indicated the surveillance was found within the acceptance criteria, and that no failures were found during the surveillance. The SRO acknowledgement and review was completed by a Shift Foreman (licensed) at 1500 on 1/23/90. A subsequent review of results was performed by a Maintenance $taf f Supervisor (non-licensed) on 1/29/90, Operating Engineer (licensed) on 2/21/90, and Technical Staff Engineer (non-licensed) on 2/28/90, and all reviews failed to identify the low voltage reading.

D. $AFETY ANALY$11:

There was no effect on plant or public safety. With one cell's voltage low, the individual cell had experienced some degradation, however, the cell would not have affected the ability of the battery bank to perforin its safety function. Also, during this period, the battery bus voltage was maintained at >126 volts at all times. In addition, IBV5 8.2.1.2.d-1, "125 Volt Battery Bank Service Test", performed 1/17/90, demonstrated the battery bank was capable of carrying all the required accident loads on the bus.

Finally, a previous analysis has shown that the battery bank with only 57 of $8 connected cells, and not cross-tied to the opposite unit, has suf ficient capacity to carry the actual I?vs 111 loads. During the period between 1/23/90 and 3/7/90, the Olvision 111 Battery Bank was not cross-tied to the opposite unit and therefore was capable of performing its design safety function.

Had this event occurred under a more severe set of initial conditions, the redundant train of batteries was always operable to provide the required DC power.

( E. CORRECTIVE ACTIONS:

Upon discovery of the low voltage condition on cell #53, LC0AR 180$ 8.2.1-la was immediately entered and NWR 874716 was written to place a single cell charger on Cell #53 to restore the cell to the required voltage. On 03/14/90 at 0856, cell #53 was jumpered out of the battery bank via Temporary Alteration 90-1-011 as interim corrective action. To complete this alteration, 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> LC0AR 180$ B.2,1-la was  !

entered. At 0925 on 03/14/90, the installation of the Temporary Alteration was completed, and the Olvision r 111 Battery was restored. LC0AR 180$ 8.2.1-la was exited. As permanent corrective action, the cell was  ;

i replaced under NWR B74736 on 03/31/90.  !

l A Personnel Error Review Board and a Human Performance Enhancement System GIPES) evaluation has been l conducted for this event. The corrective actions to ensure the acceptance criteria are properly identified l and ensure the procedure is adequately reviewed are as follows:

l

1. Remove the existing Technical Specification Table used for the acceptance criteria, and replace it with specific setpoint limits relating to minimum voltage, specific gravity, temperature and corrosion.

This will enable an easier comparison of actual data vs. Its associated Technical $pecification value.

Action Item Record (AIR)90-079 will track this item.

2. Add notes to the surveillance ahead of acceptance criteria steps stating to stop and contact the $hif t Engineer when the acceptance criteria is not met. AIR 90-079 will track this item.

(0553R/0065R)

p. ,

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LIEEN$EE EVENT REPORT (LER) TEXT CON 11 M LION form ptLM FACILITY NAMC* -(1) DOCKET nut @ER (2) LER NUPSER (6) page (3) ,

• ** Year / Sequential // Revision j/j/j/

// Number j///j/j Number

.h ron. Unit 1 0 l 5 i O l 0 1 0 1 41 51 4 910 - 01013 - 01 0 0! 4 0F 01 4 Text Energy Industry Identification System (E!!$) codes are identified in the text as (XX)

3. Add a signof f to the data sheets to verify the acceptance criteria for each step has been met. AIR 90-079 will track this action.

4. The Electrical Maintenance Department will be briefed on this event and the corrective actions to be

• taken. AIR 90-080 wt11 track this action.

5. Add acceptance criteria "g" signs to the Data $heets to properly identify when acceptance criteria data is being taken. AIR 90-079 will track this action. l

6. Review other Electrical Maintenance surveillances for similiar problems, and make any changes as '

necessary. AIR 90 081 will track this item.

7. A Required Reading package etntaining a summary of the event and a copy of the performed data sheets will be routed within the Electrical Maintenance and Operating Departments. AIR 90-082 will track this item.

While reviewing the calculations allowing the temporary alteration to be Installed, a potentially reportable condition was discovered. A supple

• ental report will be submitted upon completion of the investigation if the event is determined to be reportable. AIR 90-087 will track the in estigation.

F. PREVIOU$ OCCURRENCE 11 One previous event was identified at Byron that resulted in a missed LC0AR and increased surveillance

, frequency due to inadequate surveillance review and improper procedure format.

WTER 111LE LER 89-001 (Docket 454) Technical $pecification Hot Channel Far. tor Surveillance Performed Late Due .

to Personnel Error.

G. (QMPONENT FAILURE DATAt l

a. tRNUFACTURER @l4ENCLATURE W DEL NUPSER MFG PART NUtBER GNB Battery Lead-Calcium Battery M01-2014-92 762098

b. RESULTS OF NpRDS SEARCH:

A Nuclear Plant Reliability Data Systems (NPRD$) search of wet cell battery f ailures identified 75 failure reports. Of these, 24 reports were due to low voltage and indicated the f ailure was thought to be due to normal / age related f ailures. A common mode failure mechanism was not identified. A .

Component Failure Analysis Report (CFAR) did not prove significant since this was the first f ailure at Byron, i

(0553R/0065R)