ML19308D424
| ML19308D424 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 05/17/1977 |
| From: | Stewart W FLORIDA POWER CORP. |
| To: | |
| Shared Package | |
| ML19308D401 | List: |
| References | |
| NUDOCS 8002280728 | |
| Download: ML19308D424 (2) | |
Text
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _. _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _
Lit,L_a WJ LL.
Lv Ll'ii itLI LJi t i CONinOL ULOCK:l l
l l
l l
l i
(PLCASC I1ntNT ALL ntoulntD INFCR.'.1 AT:C.
1 G
LCENSEE a j'.m LCENSC EVENT t
N NAME LCENSE NUMUEn TYPE TveE
\\
,l F l L l Cl Rl P l 3l l 0 l 0*l-l 0l 0l 0l 0l 0l-l 0l 0l l4 l 1l 1l1l1l l0 l3 l 7"UD 14 15 25 20 30 31 32 Tyk S[)E cAftconY coCKET NUMOEA EVENT oATE REPoni oAtE
@ CONT l - l - l W l Ll l0l5l0l-l0l3l0l2l l0 l4 l 2l 7l 7l 7 l l0 l5 l1 l7 l7 l7 7 0 57 bu 50 00 61 60 GU 74 7b t
EVENT DESCIUPTION
@l In Mode 1 ope ration, Control Rod Group 7 dropped into the core on two occas' ions caus'ing 7 09 ti 0
l the overlap between Croup 6 and 7 to be less than 25% contrary to Technical Specification 7 n0 U
@l 3.1.3.6.
Redundancy N/A.
First and second occurrence of this type.
On both occasions.
7 Hu U.
0 l
the croun was retrieved and the overino adiusted to within 7 u9 the soecified if mits in the G.
o l
required time frame.
(LER 77-43) 7 0U pauE bs SYSifM CAUSE COMIONENT COMPONENT CODE CODE.
COMPONENT CooE SUPPleA MANUFACTUACR VOLAtON
@ l Rl Bl lE l l Cl Rl Dl Rl Vl El lNl lD l 1l 5 l 0 l lN l l
7 09 10 11 12 17 43 44 47 48 CAUSE DESCRIPTION 0
Ql The cause of these occurrences appears to have been a grounded shield in a connector 7 a9 Ql to the 24 volt program:ner that was not identified until after the second occurrence.
bi 7 H9 C*
The connector was repaired, clearing the ground and restoring the system operable.
Gi F AJiln Y METHoo oF STATUS
. % POWER oTHEn STATUS otSCovEnY otSCoVERY oESCRiPTON Q
[El l1l0 l0 l l
N/A l
l N/A l
70 9
10 12 13 44 45 46 BC Fo4M oF ACTMfY CONTENT nELE ASE D OF RELE ASE l AMOUNT oF ACTMTV LOCATION oF AELEASE 1
l Zl W
N/A l
l N/A l
7 0 3
10 11 44 45 O(
PERSONNEL EXPOSunES NUMDEA TYPE DESCAiPTON
$ l0l0l0l Wl N/A j'i 7 09 11 12 13 60 PEnSONNEL INJunIES NUMDE H DESCRIPTION 8 1 0l 0l Ol I
N/A l
7 00 11 12 80 OFFSITE CONSEOUENCES
@l N/A ll LOSS On OAMAGE TO FACILITY 00 I T Yl'E oESCIMDION 3 l._z,J l
N/A l
7 89 10 60 PUDLICITY
][
N/A l
7 89 co IOITIONAL FACTORS 1
Sec ateachod Supplenentary In fo rtna ti on
_,,, l 8002 280D O
/ uo
-- ;;J l
NAui. -
1.r. p m n... \\ > t
,,,,,m,. ou u see.-m
\\v]/
f SUPPLEMENTARY INFORMATION 1.
Report No:
50-302/77-43 2.
Facility:
Crystal River Unit #3 3.
Report Date:
17 May 1977 4.
Occurrence Date:
27 April 1977 5.
Identification of occurrence:
Regulating rods Group 7 out of specified limits contrary to Technical Specification 3.1. 3.6.
6.
Conditions Prior to Occurrence:
Normal Mode 1 steady state operation.
7.
Description of Occurrence:
i.
On two occasions, 0417 and 1020, regulating rods Group 7 dropped into the core causing the overlap between Group 6 and 7 to be less than the required ' overlap of 25%. On the first occasion, Group 7 automatically withdrew and the overlap was manually adjusted to the specified limit within the allowed time frame. The second occasion, Group 7 was re-latched and the overlap was manually adjusted to the specified limit s_
in 50 minutes.
8.
Designation of Apparent Cause of Occurrence:
The first occasion was investigated and no cause was determined. On the'second occasion, further investigation revealed a grounded connector shield in the 24 volt programmer.
9.
Analysis of Occurrence:
At no time during these two occurrences was the safety of the general public affected.
10.
Corrective Action:
i The connector in the 24 volt programmer was repaired.
This was thought to have been the corrective action solution, however, a 'similar event occurred on 13 May 1977.
Investigation into this problem is underway.
The latest occurrence will be reported when further information can be obtained.
11.
Failure Data:
These were the first and second occurrences of this type.
s._-
,n--
-,.