05000285/LER-1982-010: Difference between revisions

From kanterella
Jump to navigation Jump to search
(StriderTol Bot insert)
 
(StriderTol Bot change)
 
Line 1: Line 1:
{{Adams
#REDIRECT [[05000285/LER-1982-010, Forwards LER 82-010/03L-0]]
| number = ML20053D914
| issue date = 05/03/1982
| title = LER 82-010/03L-0:on 820430,during Routine Operations,Reactor Protection Sys a Channel Trip Unit 3 (Reactor Coolant Flow) Setpoints Drifted Out of Spec in Nonconservative Direction. Caused by Faulty Negative 15-volt Power Supply
| author name = Mueller R
| author affiliation = OMAHA PUBLIC POWER DISTRICT
| addressee name =
| addressee affiliation = NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
| docket = 05000285
| license number =
| contact person =
| document report number = LER-82-010-03L, LER-82-10-3L, NUDOCS 8206070435
| package number = ML20053D910
| document type = LICENSEE EVENT REPORT (SEE ALSO AO RO), TEXT-SAFETY REPORT
| page count = 4
}}
{{LER
| Title = 
| Plant =
| Reporting criterion =
| Power level =
| Mode =
| Docket = 05000285
| LER year = 2082
| LER number = 10
| LER revision =
| Event date =
| Report date =
| ENS =
| abstract =
}}
 
=text=
{{#Wiki_filter:NRC F oRM y                                                                                                                  U. S. NUCLEAR RE2 ULATO7.Y COMMISSIOiJ (7 77)
LICENSEE EVENT REPORT CONTROL BLOC.<: l 1
l l    l    l    l lh 6
(PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION)
  ?
0 1 8 9 lNlE          l F l C l S l 141 l@l LICENSEE CODE                        IS 0 l 0 l 0 l 0LICENSE l 0 l 0NUMBER l 0 l 0 l 0 l 0 l 025 l@l26 4 l 1        l 1 l 1 l 1 l@l57 CAT LICENSE TYPE Jo l
b8 l@
CON'T IOlil 7        8 Z "C          l60' l@l 61015 l 0DOCKET        l 0 l NUMBER 0 l 2 l 8 l 568l@l69 0 l 413            l 0 l 8 l 21@l EVENT DATE          74      75 01510        l 3181280l@
REPORT DATE EVENT DESCRIPTION AND PROBABLE CONSEQUENCES h l o l 2 l l During routine operations at approximately 99% power, the Reactor Protective System                                                                            I g o ,3 ; ;"A" channel-trip unit No. 3 (Reactor Coolant Flow) setpoints had drif ted out of speci-l lol4llficiation in the nonconservative direction. Maintenance Order 14828 was written to                                                                                  l
[og.,;l Investigate the drift. The R.P.S. was immediately placed in a two-out-of-three logic l
,10161 l trip mode (fOr Reactor Coolant flow c:annels Oniv). Technical Specification 1.3(2) and o ,      l2.15 apply.                                                                                                                                                l
                                                                                                                                                        ~
101811                                                                                                                                                                      l E            CODE          SUBCO E                COMPONENT CODE                SUSCOD'E          SU    E 7
O 9 8                          9 ll lAl@ J @ W @ lllNlSlTlRlUlh W @ W @
10          11              12            13                        18          19              20
                                      ,,,                                        SEQUE NTI AL                    OCCURRENCE          REPORT                    REVISION LE R/RO          EVENT YEAR                                REPORT NO.                        CODE              TYPE                        NO.
                @y    R l8l2l                l-l              l 0l 1l 0l            {f__j        l0l3l                [,L j          ( ,)      [0_j 21        22        73              24          26      27          28      29          30            31        32 T If N AC O                      ON PL NT            M T                    HOURS          S8 IT D        FOR      8. SUPPL              MANUFAC RER lA JJ lgl34Zlg                    ]g 35
{@
36 l 0l 0l 0l 0l 3s                  40 W@ lNl@ lNl@ lPl3l114l@
41              42                43          44            47 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS h l i l 0 l lAf ter troubleshooting, it was discovered that the setpoints had drif ted out of soeci- l 3 i        l fication due to d faulty negative 15 volt Power supply (which feeds tne trip unit).                                                                    _
I g , ; 2 g lThe power supply was replaced, the unit was calibrateO per calibration procedure CP-                                                                              l 3 3      lRPS-3 and proper operation of the trip unit verified per applicable surveillance test.I i 4      lThe unit was returned to service in less than 8 hrs. from initiation of the problem.                                                                          l 7        8 9                                                                                                                                                            80 ST      S              % POWE R                        OTHER STATUS              IS O      Y                      DISCOVERY DESCRIPTION l i l s l [E,_J@ l 0 l 9 l 9 l@l                                        NA                l    [A_J@l              Operator Observation                                  l A TlVITY CO TEt. ;
RELEASED OF RELEASE                            AMOUNT OF ACTIVITY                                                  LOCATION OF RELEASE i r2      [Z_] @ [Z,,J @l                                NA                            l        l      NA                                                          _l 7      8 9                  10            13                                          44        45                                                                  80 PERSONNEL EXPOSURES NUUS E R                TYPE        DESCRIPTION i i      l010 l0 l@y@l                                            NA                                                                                                  l PERSONNELINJU IES NUMBER                  DESCRIPi10N i a                                                  NA                                                                                                                l
.7        .a 9 l 0 l 0 l 0 l@li2 si                                                                                                                                        80 LOS$ OF OR DAMAGE TO FACILITY TYPE        DESCRIPTION 9                                            NA                                                                                                                    l
(_Z_J@l                                                                                                                                                    s0 7        a e            30 Puaucuv                  8206070435 820528                                                                                            NRC USE ONLY
* PDR ADOCK 05000285                                                                                                                    .
2 O      usuto@DESca
[N_J        l                S                                  PDR                                                          l    llllllll1IlIli 7        8 9            to                                                                                                                68 69                        80
! ._ _ . m.NAME oF PREPARER                                          an@ M1er                                                  POE                                                  ;*
 
O lek No. 82J010 Omaha Public Power District Fort Calhoun Station Unit No. 1 4
Docket No. 05000285 Attachment No. 1 Safety Analysis The Fort Calhoun Station Reactor Protective System (RPS) is de-signed such that no single failure can prevent the RPS instrumentation and equipment from performing its design safety function.                      During the inoperability of the RPS channel "A", trip unit No. 3                    " Reactor Coolant Flow", the three remaining reactor coolant flow trip channels (B, C, and D).were operable and functioning at the appropriate setpoints. Since channel "A" was immediately placed in the bypass condition,.the RC flow-channels were then operable in a two-out-of-three trip _ logic until the faulty power supply could be replaced and the subject trip unit re-calibrated.
The trip setpoints for the RC flow channels of the RPS are verified monthly per Surveillance Test ST-RPS-3, F.2. This monthly surveillance test ensures the RC flow pretrip and trip setpoints are properly function-ing and will detect setpoint drifting or system malfunction.
***M"''A.a > -m  me #  Q4  4 , fr. 6 -+ %p e p; dm A%
* m e  w- % ._eM M**
* a d Wh W .4  ,M M  , ,W J w %daus a 4'kF L 4W i' 9 '. 414' We i AIW-
 
s LER No. 82-010 Omaha Public Power District Fort Calhoun Station Unit No. 1 Docket No. 05000285 Attachment No. 2 Corrective Action Upon inspection of the trip unit and associated circuitry, it was discovered that the RPS "A" channel trip unit No. 3 had a faulty negative 15 volt power supply. The defective trip unit was-immediately placed in
        " bypass". The power supply was replaced with a spare. The trip unit was recalibrated per calibration procedure CP-RPS-3, satisfactorily tested for operation via applicable portions of surveillance test ST-RPS-3, F.2 and returned to operation. This repair process took less than 8 hours to complete.                                        .
                                    ..-.w -
                                            ...--+++.mm % ~u - aan-- .,=  A<~~ e . u+,
 
LER No. 82-010 omaha Public Power District Fort Calhoun Station Unit No. 1 Docket No. 05000285 Attachment No. 3 Failure Data This is the third reportable failure of a Reactor Coolant Flow Channel. The first and second failures were reported per LER's 78-20 and 80-12, respectively.
w.s                    ,  ..+    . . , , . .        ,s a  s ,e wwa s -  .a . a u ,a2  n . .4 ~, *~
}}
 
{{LER-Nav}}

Latest revision as of 04:27, 19 March 2020

Redirect to:

Retrieved from "https://kanterella.com/w/index.php?title=05000285/LER-1982-010&oldid=2629041"