05000317/LER-1981-005-03, /03L-0:on 810119,during Surveillance Testing, Containment Cooler 14 Would Not Start in Slow Speed.Caused by Contacts Not Closing on Slow Speed Motor Starter Interlock Contact Assembly Due to Cracked Case

/03L-0:on 810119,during Surveillance Testing, Containment Cooler 14 Would Not Start in Slow Speed.Caused by Contacts Not Closing on Slow Speed Motor Starter Interlock Contact Assembly Due to Cracked Case

ML20003B756
Person / Time
Site:	Calvert Cliffs
Issue date:	02/17/1981
From:	Lagiewski J, Rizzo P BALTIMORE GAS & ELECTRIC CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20003B753	List: 05000317/LER-1981-005, Forwards LER 81-005/03L-0 05000317/LER-1981-005-03, /03L-0:on 810119,during Surveillance Testing, Containment Cooler 14 Would Not Start in Slow Speed.Caused by Contacts Not Closing on Slow Speed Motor Starter Interlock Contact Assembly Due to Cracked Case
References
LER-81-005-03L, LER-81-5-3L, NUDOCS 8102250447
Download: ML20003B756 (2)

LER-1981-005, /03L-0:on 810119,during Surveillance Testing, Containment Cooler 14 Would Not Start in Slow Speed.Caused by Contacts Not Closing on Slow Speed Motor Starter Interlock Contact Assembly Due to Cracked Case

Event date:
Report date:
3171981005R03 - NRC Website

text

NRC F-1 C65 U. S. NUCLEAR REGULATORY COMMISSION (7 77; LICENSEE EVENT REPORT A

CONTR ol B LOCK: l l

l l

1 l

(PLEASE PRINT CR TYPE ALL REQUIRED INFORMATIOM iotillsiO!CICini1 gl010!-10!0101010l-l010 @l411 il il il lel l@

7 3 3 LICENSEE CCCE 14 15 i.iCENSENwMdER 25 46 L. CENSE TY PE 40 57 CAT 5d CCN'T lclil ZRc! l L @l 0 i 5 l 0 l 0 l 01311 l 7 @l 0 l1 l1 l9 ! 811 @l012 Il 171811 l@

7 d

60 61 DOCKET %v9ER 68 63 EVENT DATE

'4

'5 REPORT OATE

$3 EVENT OESCRIPTICN AND PROBABLE CONSECUENCES h 10121 l At 0430, during the cerformance of surveillance testina, #14 Containment 1

i o,2 i l Cooler would not start in slow soeed (T.S. 3.6.2.2).

Corrective reoairs I

ioi.il were made and the unit returned to service at 2055. Three Containment I

io isi l Coolers remained ooerable during the event.

This has not been a repet-1 io ;3 i l itive event.

l Io i7I i I

i o !8 i i I

$0 7

$-3 E

CO E SL8C E COMPONENT COCE SUSC CE S

E lol31 l S l B l@ [ A l@ lC l@ lC lK lT IB [R lK l@ l 0 l@ W @

7 6

3 to 1'

12 13 18 19

0 CCCURAENCE REPCRT REWSION SEC,U ENTI AL RE CRT No.

CCCE TYPE No.

t EVENT YEAR

@ r=ga Ro l 8[ 1[

l_l l O! 01 Sj l/l l0l3l lL l l_l l0[

,_ 2 '

22 23 24 26 27 23 23 30 31 32 TAKE A

C CNPLANT T C HOURS SB I FCR S.

S8 IER VANLFAC RER lAl@lHl@

l Z l@. l Zl@

l 0l 0l 01 0l l Yl@

l Y l@

l Al@

l I l 0 l 0 l S l@

33 34 35 36 3/

40 41 42 43 44 47 cAusE oESCRIPTION AND CCRRECTIVE ACTIONS h li t a ; l The Slow Soeed Motor Starter Interlock contact assembly was found to be I

t i !i i i inocerative due to damaae caused by overtichtened mountinn screws.

The 1

i,,7, I

case was cracked, creventina contacts frem closina. The cart was re-l i,13 I

olaced with a scare.

Electrical fiaintenance eersonnel will be instruct-1 i, iA i l ed in these consecuences and methods to orevent similar errors.

I 7

9 3.

40 ST

'n PCWER OTHER STATUS ISCO RY DISCOVERY DESCRiPTICN Ii i 5 l l E l@ l01910 'l@l NA l

lBl@l Surveillance Test l

i2 o

a 45 46 80 CcTrENT ACTIVITY RELEASE AMCUNT OF ACTIVITY LCCATION CF RELE ASE l i i s l l Z i @D CF RELEASEW@l NA l

l NA l

neRSoNNEL ExpoSOES ESCRieTicN@

NuusER rY,5 li 121 l 010 l 0 l@l Z l@l NA l

~"

,ERScNNEt.N;uViES cESCRipr,cN@

NuveER It lal10101Ol@l NA l

7 d 9 11 12 80

$5,5

$ ESC #T o'N '' " @

5 I t 191 l Z i@l NA l

7 d 9 10 80 j,,2,,LoJ l N f@TE Cai,TicN@

8102250 447 NR uss cNa iSSU E l

yA I

i ll1IIIIII!Il; 68 69 30 5 7

3 3 TO J.S. Lagiewski/P.G. Rizzo

,ygga. (301) 269-4747/4786 2

NAME c m sn aEa

LER NO.

31-05/3L DOCKET NO.

50-317 LICENSE NO.

DPR-53 EVENT DATE 01-19-81 REPORT DATE 02-17-31 ATTACHMENT CAUSE DESCRIPTION AND CORRECT VE ACTIONS (CONT'D)

The damaged Slow Speed Motor Starter Interlock assembly's (ITE Catalog No. FIONOCL) function is to short some of the Slow Speed Starter Coil windings allowing sufficient current through the remainder of the coil to operate motor contacts. The broken case resulted in an open circuit through the assembly so that all coil windings were in the circuit, preventing contact actuation.

The assembly's mounting screws were stripped, indicating they had probably been inserted cross-threaded during a previous maintenance activity. This required excessive force to tighten the screws, overstressing the molded case of the Interlock assembly.

All Electrical Maintenance personnel will be instructed in these consequences and methods to avoid similar errors. Action will be completed by February 20,1981.