ML17252A269

Transmittal of Reportable Occurrence Report No. 50-249/1976-32

ML17252A269
Person / Time
Site:	Dresden
Issue date:	12/02/1976
From:	Stephenson B Commonwealth Edison Co
To:	James Keppler NRC/RGN-III
References
BBS Ltr. #76-845 50-249/1976-32
Download: ML17252A269 (3)

Text

e Commonweal9dison Dresden Nuclear Power Station R.R. #1 Morris, Illinois 60450 Telephone 815/942-2920 BBS Ltr. #76-845 December 2, 1976 Mr. James G. Keppler, .

Regional Director

\

Directorate of Regulatory Operations - Region III U. S. Nuclear Regulatory Co'mmission 799 Roosevelt Road Glen Ellyn, Illinois 60137 Enclosed please find Reportable Occurr~nce report number This* report is being submitted to. your office in accordanc1 with* the Dresden Nuclear Power Station Technical Specifications, Section 6.6.B.

eph son Station Superiritendent Dre~den Nuc!'ear Power Station BBS :jo

• Enclosure cc: Director of Inspection & Enforcement l;lirector of Management Information & P*rogram Control File/NRC DEC 7 1976

.. LICE~SEE EVENT REPORT -

CONTROL BLOCK: I I 1

! I *. I *. I I .

• 6 (PLEASE PRINT ALL REQUIREOINFORMATION)

LICENSEE LICENSE EVENT NAME LICENSE NUMBER TYPE TYPE

@E] 1Ilt..IDIRISl31. 10101~10101016101-10101 1~111111111 10131 7 8 9 14. 15 ' 25 26 30 31 32 REPORT REPORT CATEGORY TYPE. SOURCE OOCKET NUMBER. EVENT OATE REPORT DATE

@E1 cowr I I I lbJ L&J !015101_.:._IOl;1..141ql I! It IOIS-171'1 1tI~1011171<01.

7 8 57 58 59 60 61 68 .68 74 75 . 80 EVENT DESCRIPTION 7

IQI?J8 9I WHILE TH£ UN!T-3 DIES.e.:L . GEN£.RATOR WA$ BEING- OPERATED .

TO .PERFORM I 80 l7o1318 8I 4 KV BRE:AKER .

SWITCH 1NCr, IT WAS FOUND TH11I THE £NGIN£" SPEED (t..oADJ I

. . . . . 80

@El lcouLP 13.£ j)ECR.£ASED BVT Nor 1Nc.Re:1tS£.D ERbpf TH£ .c.D!IJTR.01- Room. FUJ...L I 7 8 9 . .. . .. . - ,~, . . . . ,._. 80

~ I.ENG-INC: SP££D. CONTROL WAS P.V!tlL././BJ..,f: AT THE J....QCAL CONTROL STfJTtotJ.. Auro-1 7 8 8 . 80/

[£ffil fYJ!f//C ST. OF TH£

• oT 'AFFECTi.D

7. 8 9 PR:ME (5£G ATTAlt1CJ) S~£ET 80 SYSTEM CAUSE COMPONENT COMPONENT CODE COOE COMPONENT. COOE . SUPPLIER

• MANUFACTURER VIOLATION

@0 IELE I l_fil 1£ IN I G 11 INIEI ll!.J llV I :l I~ IO I lM 7 8 9 10 11 12 17. 43 : 44 47 I 48 CAUSE DESCRIPTION ..

lolsl8 8I TUE FAILURE WAS Cl\(;)$£D"--*ey"1k\*:7nsG:8.i§iN1C:AL tr1AiFVN~T10/.i oF*'_*:.if.1£~':*RAtSE *I.

7 . .* . . 80

• ~

7 8 8 I OVERTRAVt.L .*1-1mrr .

SWl'TU1 ONT!{ f)IESE& GoVE:/SNOR. e Tl-I/$ SWITGH LI vYI ITS 80 I

IT@ l]}.IE GOvERNoR.. sE:TT1N(;... ro A No~1-0Ao f::RiQ.itep.ic;v~ or!/~ -~~-fub. Hz

• FDJ..-Low1N& I T' 8 8

.. i=Ac1i:1ry

.. ~ETHOO OF .

($6£ R7rl'C~D ~ltSCT) 80 .

.. -.STATUS  % POWER OTHER STATUS DISCOVERY . DISCOVERY DESCRIPTION EEJ8

7. .

lliJ 9 . .

IO I oj o I 10 . 12 .. 13 .

vA 44

@.j 45 46 AIA

~----,--~----,-------*

80 J

FORM OF ACTIVITY CONTENT rn .~ *lZJ 7 8 RELEASED

.8 .

OF RELEASE 10 11 L.-1_

AMOUNT OF ACTIVITY

____,.._.,_/0_~_-"--__.

44 45 I

~-~~---"M~n~~~-*~~~_.I LOCATION OF .RELEASE 80 PERSONNEL EXPOSURES NUMBER TYPE DESCRIPTION

~ .101C>I01 lZJ ._____M_'.4-_*----------------~80 7 9_9. *11- 12. 13-PERSONNEL INJURIES NUMBER . DESCRIPTION EEi IO Io 10 I "'----~M.;..;..lfl.::-.- _______________________,_

7 8 9. 11 12 80

• OFFSITE CONSEQUENCES 12nl..

7 8 8. .

J\I. .

. 80 LOSS OR DAMAGE TO FACILITY TYPE DESCRIPTION

!))].

7 8 lZJ 10I .

9.

di/

80 PUBLICITY

. -*Bil I -- N/I .

7 8 8 80 ADDITIONAL FACTORS

~ /I/If 7 8 8 80

~ 80 7 8 9 NAME: TER.R.ANC£ £ ~ /_ANG- PHONE: £xr. 433 GPO 881 * ~67

_EVENT DESCRIPTION (Continued) by this failure. The lJnfr 2/3 diesel generator was immediately verified to be operable, as were the. Uni_t...:J. LPCI, core.spray, and *ccsw systems. (50-249/1976-32)

. ~ . *' '

• CAUSE DESCRIPTION (Con.tinued).,

the shutdown o,~~-~he* diesel. "The~'§_witch was apparently actuated when the diesel was last shut\gowq:,: and ,.remained open after. the subsequent start-.up of the diesel.

The failure of'the switch to close after start-up precluded remote speed control of the diesel in the manual mon~~

Th~-.;.--rais~

r_,,,._...r.,-_.,_:~-~.P"'o-overtravel limit sJ.~Tuh.

._,~~

incorporates

.a

• microswitch ~ith an attached

. ' actw~~g~&r~1! The 11m1t switch was found out of adJustment, apparently due to.

vibration;allowing the limit switch to remain open after start:....up of the diesel.

The switch arm was *actuated manuall.Y to ensure free movement of the contacts, and the actuating arm *was reset slightly .. -

.To prevent recu!rence, a modificatic>n request has been subm_itted t:o remove the, raise overtravel limit switches from the Unit-2, Unit-3 and Unit 2/3 diesel governors.

Since no-load frequency.for the diesel generators can be regulated.from the control room, the removal of these switches will have no-adverse effect on diesel generat:or

• frequency control. ;. A similar failure occurred on the Unit-:-3 diesel generator in 1972 . . The diesel governor _is a model uc..:.8 unit manufactured by the Woodward

.Go'vernor Company.