ML20064G731

/03X-1 on 781107:malfunctions in 1A,1C & 1D Circulator Speed Measurement Caused Loss of High Speed Circulator Signals on Different Dates,Due to Elec Circuit Unbalance & Signal Cable Resistance Change in Modifiers

ML20064G731
Person / Time
Site:	Fort Saint Vrain
Issue date:	12/07/1978
From:	Gahm J PUBLIC SERVICE CO. OF COLORADO
To:
Shared Package
ML20064G723	List: ML20064G717 ML20064G725 ML20064G731
References
LER-78-005-03X, LER-78-5-3X, NUDOCS 7812130185
Download: ML20064G731 (7)

Text

7 7[*

. .. LICENSEE EVENT REPORT

• tCONTEOL8 (PtgAss PRINT C2 TYPg ALL RESul%E3 INPOEMATIONI

)C: l l l l l l 0l 0l 0l 0l 0l2h@l 4l uCENSE 1l 0 ll 2l 0l@l57 GAT l@

l Q 111 4 9 l CUCENSEE l O lCODE F l S l V l 1 l@15 0luCENSE 84 0l 0lNUMSER Ol26 Ol TYPE Jo 54 CON'T I

0111 3 umy l L l@l O l 5 l0 l 0 l0 l 216 17 @ll 11 10 1717 18 @l175 l 2 l 0 l 7 l 7 l 880]@ 74 4 60 el DOCKET NUMeER 68 09 EVENT DATE REPORT QATE EVENT DESCRIPTION AND PROBABLE CONSEQUENCES h iol2l l Operations personnel observed that taalfunctions in lA. 1C and ID cf re iil menr en..A l l o 13 l l measurement caused loss of circulator high speed signals. Problems occurred at I l o 14 l l different dates. circulators not affected at the same time. Reoortable ner l Ioi5l l Technical Specification AC 7.5.2(b; . operation under a degraded mode permitted by l

~

(( Tin -l -Lb0 4.4.1.-No-ehfeet on plant operation. Probable consecuence was loss of hinh l 7j l speed circulator trip function. No affect on public health or safety. Redundant I i o i8 i i system available and operable for each circulator. I E ODE SueC E COMPONENT CODE SU0 CODE SU E g lI lB l@ y@ l El@ lI l N l S l T l R l U l@ W@ y @ 13 18 19 20 7 s 9 to 11 -

12 SEQUENTIAL OCCURRENCE REPOMT REVISION LER EVENT YEAR .

REPORT NO. CODE TYPE NO.

@ ,ag/RO 17181 L-J 1010151 l'l 10131 1 xi 1-1 111

,,,, 21 22 23 24 26 27 28 29 30 31 32 K r) AC 0 0 T METH HOURS 58 ITT POR Us. SU U MANUP URER lx 33 l@l34xl@ LZ_1@

35

~13J@

36 l010IoIoI 37 40 LI.J@

el ULi@

42 LN_l@

43 lcl2l9l0l@

44 47 CAUSE DESCRIPTION AND CORRECTTVE ACTIONS h I t 1 o l l General Atomic circulator speed / wobble modifiers caused a loss of plant protective l I

' g l system functions to high speed trip circuits due to electronic circuit imhainnce and I

.h l signal cable resistance change. Modifiers adjusted, installed spare cable connected l li,i3i j as applicable. Adjustment of speed modifiers being checked weekly. Problem under I i,i,i l inves tigation. I 80 7 8 9 STA  % POWER ' OTHER STATUS RY DISCOVERY OESCRIPTION m LEJ@ l 0l 317 l@l N/A [ 015 Ol A l@l Operator Observation l u a_ a e a a 7

a4 ig7,,, -

EELEASE AYOUNTOF ACTIVITY LOCATION CP RELEASE l1 l 6 l l Z l @D CP RELEASE N/A lZI@l l l N/A l 7 8 9 10 tt 44 46 80

! PERSONNEL EXPOSURES NUMeER rYPE cEsCRiPTiON ,

l l 1 l 7 l l 0l 0l 0l@l Zl@l N/A PERSONNE L INJURIES NUMBER DESCRIPTION l l1 la3 l9l 0l 0l 0l@l12 N/A 80 l

l7 11 LOSS OF OR OAM AGE To FACluTY t TV'E O ESCRIPTION N/A l i

11191 7 d 9 l Zl@lto 60 issug CE CRIPTION 8, W lN fhl 7 3 3 10 N/A l 68 69 llllIlll 1!lIli

30. I aEPARER l' N* 08h8 PHONE: (303) 785-2253 f,