ML20009B994

LER 81-017/03L-0:on 810619,during Reactor Protection Sys Motor Generator Set Relay calibr,3B Set Undervoltage Relay Failed to Trip on Undervoltage Signal.Cause Will Be Determined When Relay Can Be Broken Down & Examined

ML20009B994
Person / Time
Site:	Dresden
Issue date:	07/10/1981
From:	Morgan W COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20009B990	List: ML20009B989 ML20009B994
References
LER-81-017-03L-01, LER-81-17-3L-1, NUDOCS 8107200128
Download: ML20009B994 (2)

Text

. -

NRC FORM 366 - - - - - - - - - - - - - - - --

-- - - . U.S. NUCLEAR REGULATORY COMMISSION (7 77)

LICENSEE EVENT REPORT CONTROL SLOCK: l l l l l l l (ptgASE t*RINT OR TYPE ALL REQUIRED INFORMATIONI i e l o l 81 9l l I l LICENSEE 7

L l D lCODE R l S 14l 3 lgl5 0 l 0 l - lLICENSE 1

0 l 0 NUM8ER l 0 l 0 l 0 l- l 0 25l 0 lgl4 ;6 l1 l1 l1 [1 UCENSE TYPE JO l l 57 CAT 58 l

CON'T lalti 7 8 3c "E'0

,"y l L @l 0 l 5 l0 JO l0 l2 l4 l9 @l0l6l 1l 9l 8l l@l 0l 7 l 1l 0l 8 l1 J@ -

60 61 QoCKET NUVSER 68 63 EVENT DATE 74 75 REPORT QATE 80 EVENT DESCRIPTION AND PROSABLE CCNSEQUENCES h l o l 21 l During RPS MG Set relav calibration. the 3B MG Set uncervoltage relay failed to trip l Al on an undervoltage signal. This was of minimal safety significance, since the pro- l

. l o 141 l tective function of the RPS system was not inhibited. There was no effect on public l loisl l health or safety. This is the first occurrence of this type at Dresden. . l lo (6 l l l l o l 71 I l I o 187 I l 7 8 9 80 0E OE SLSC E COMPONENT CODE SUS ode SU E 10191' l Il A l@ lE l@ l Al@ lR lE lL l A [Y lX l@ l D l@ J Z [Q 7 8 9 10 11 12 13 18 19 20

_ SEcutNTIAL oCOURRENCE REPORT R EVISION LER/Ro EVENT YEAR REPORT No. CODE TYPE No.

@ RE l8 l1 l 21 22 l-l 23 l0l1l7l 24 26 l/l 27 l 0l 3l 28 29 lL l 30 g

31 l0l 32 N ACT ONP T ME MouRS 22 S8 i PCR 8. SL MANUP RER LvJ@l2J@

33 34 1.z_.1@

35 Iz 36 l@ l 37 I I I I 40 I"_J di

@ l' !@ l El@

42 43 l44G I o I 8 I o47f@ -

CAUSE DESCRIPTION AND CORRECTIVE ACTIONS h li io I l The cause will not be resolved until the relay can be broken down and examined l li ii i i during the next scheduled unit outage of sufficient length. Upon discovery of the gl nature of the problem, the relay will be repaired or replaced, and a supplemental LER g

,,,3, l will be submitted. The 3A Reac' tor Protection Bus will remain on the backup power  ;

l l supply until the relay is repaired.  ;

7 S 9 80

( STA  % POWER CTH ER STATUS iO RY DISCOVERY CESCRIPTIoN l ii 15 I (,E_j@ l 0 l 8 l 9 l@l N/A l l l@ldeRoutine Surveillance l 7 12 is 44 4s so 8 4 ,,, 1g7, rELnSEo CP RELEASE LOCATION OF RELEASE @

M [3]h lZl@l N/A AMCUNT OF "

ACTIVITY @N/Al l

l PERSONNEL ExPcSuRES NUMSER TYPE CESCRIPT1oN l 1 l 7 l l0 l 0 l0 l@lZ l@l N/A l PERSONNe'L iNau'R,,,

2 i3 so NuMsER CESCRiPrioN l7 t l a8 l9l 0 l 0 l 0 l@l12 N/A l 11 90 E CE PT N l7 t 191 l Z l@l N/A l .. _

• • 8 PUsuNTv 9107200129 810710 NRC USE ONLY PDR ADOCK 05000249 QQjlNfhlcESCRiPTiON @

issue , ,

N/A S PDR l lllllll[ l!It[j  ;

7 8 9 10 68 *' S0 5

_y Wayne Morgan g, 942 920 Ext 422 o I

w

,. (d s

DEVIATION REPORT

, \- ova so, -

Commonwealth Ed,i son STA UNIT YEAR N O.

D - 12 81 - 36 PART Il TI TLE OF DEVIATION OCCU RRED 3B RPS MG Set Failure to Trip on Undervoltage 6/19/81 10:25 g ,7g 7, yg SYSTEM AFFECTED 500 PLANT CONDITIONS TESTING Rx Protection Run 2250 715

~

DESCRIPT.ON OF EVENT During RPS MG Set undervoltage relay calibration, the 3B RPS MG set failed to trip on an undervoltage signal.

DESCRIPTION OF CAUSE Unknown at this time. *

~

WTHER AP LICABLE INFORMAT10N None EQUIPMENT C YES OR NO. W8 NO.

Michael Wright 6f19/81 FAILURE R NO N/A 14290 RESPONSIBLE SUPERVISOR DATE PART 2 l OPERATING ENGINEERS COMMET o The 3A RPS Bus will remain on backuo feed until the tripping problem is resolved.

SAFETY-TYPE OF CEVIATION EVENT OF POTENTIAL TECH SPEC NON-REPORTABLEANNUAL l RELATED R_EPORTABLE OCCURRENCE PUBLIC INTEREST VIOLATION OCCURRENCE REPORTING WR ISSUED 10CrR21 YES y 1 14 OAY _ YES x lXl30 CAY T1 FI Ct.T I ON l _ NO NO 6.6.B.2.5 RIPORT/BLE OCCURRENCE ACTION ITEM NO. PROMPT ON-SI TE NOTI FI CATION NUMBER R. M. Ragan 6/19/81 l'. : 30 TITLE DATE _T i '4 E TITLE CATE TIME 0

24-gggA N PROMPT OFF-SITE NOTIFICATION tebRf NOTI F? CATION X TPH M. Jordan 6/19/81 1100 F. Palmer 6/19/81 12:42 REGION 111 CATE TIME TITLE DaTE TIME TGM REGION lli & COL CATE TIME T I TL E CATE TlvE RESPONSIBLE COMPANY OFFICER INFORMED OF 10 C F R 21 CONDITlONS AND TWEl R AEPO AT TO NPC + TlTLE CATE i i M ::.

REV1 EW AND COMPLETED Michael Wright 6/19/81 OPERATi % ENGINEkM e DATE CCEPT BY STATION PEVIEW #

jg {g 1 + .

DATE b# ~

- / -

RESOLUTION APPROVEC AND /h1 k j AUTHORIZED FOR CISTRIBUTION '

SJrATIOS SUPERINTENDENT

....,n ,e n m ,....n.n u ef /' EATE I

. - __ _