ML20084K622: Difference between revisions

From kanterella
Jump to navigation Jump to search
StriderTol Bot insert
 
StriderTol Bot change
 
Line 18: Line 18:
=Text=
=Text=
{{#Wiki_filter:~
{{#Wiki_filter:~
              - , &                  (O                               O G
(O O
    * * -      - .0                 'O REPORT hWBER: A0-50-.265/74-11 REPORT DATE: June-21, 1974 OCCURRE?;CE DATE: June 13, 1974 FACILITY: Quad Cities Nuclear Power Station Cordova, Illinois 61242 IDEUTIFIC ATION OF OCCURRENCE:
'O G
.0 REPORT hWBER: A0-50-.265/74-11 REPORT DATE: June-21, 1974 OCCURRE?;CE DATE: June 13, 1974 FACILITY: Quad Cities Nuclear Power Station Cordova, Illinois 61242 IDEUTIFIC ATION OF OCCURRENCE:
Condenser Pit Five-Foot Level Switch failed to actuate Control Room Annunciator during monthly testing.
Condenser Pit Five-Foot Level Switch failed to actuate Control Room Annunciator during monthly testing.
CONDITIONS PRIOR TO OCCURRENCE:
CONDITIONS PRIOR TO OCCURRENCE:
1     Unit 2 Reacter in cold shutdown.
1 Unit 2 Reacter in cold shutdown.
2     All three Unit 2 Circulating Water Pumps operating.
2 All three Unit 2 Circulating Water Pumps operating.
DESCRTW TON OF OCC m W CE:
DESCRTW TON OF OCC m W CE:
Level Switch LS-2-4441-24A did not actuate the Control Room Annunciator when monthly surveillance of the Condenser Pit Five-Foot Level Switches was performed in accordance with Technical Specification 4.5.H.1.d. This switch circuitry was jumpered in the tripped fail-safe condition oer^
Level Switch LS-2-4441-24A did not actuate the Control Room Annunciator when monthly surveillance of the Condenser Pit Five-Foot Level Switches was performed in accordance with Technical Specification 4.5.H.1.d.
This switch circuitry was jumpered in the tripped fail-safe condition oer
^
Technical Specification 3.5.H.2 A work request was imediately initiated to investigate and repair the apparent malibnetioning trip and alarm cir-cuitry.
Technical Specification 3.5.H.2 A work request was imediately initiated to investigate and repair the apparent malibnetioning trip and alarm cir-cuitry.
DESIGNATION OF APPARE?"P CAUSE OF OCCURRE'!CE:                 N.
DESIGNATION OF APPARE?"P CAUSE OF OCCURRE'!CE:
N.
4 The apparent cause of the failure of the surveillance test of LS-2-4441-24A to actuate the Control Room Annunciator is that the Level Switch Float Plunger was not fully lifted vertically during testing, thus not closing the switch contacts.
4 The apparent cause of the failure of the surveillance test of LS-2-4441-24A to actuate the Control Room Annunciator is that the Level Switch Float Plunger was not fully lifted vertically during testing, thus not closing the switch contacts.
ANALYSIS OF OCCURRENCE:
ANALYSIS OF OCCURRENCE:
Line 33: Line 37:
CORRECTIVE ACTIO?!:
CORRECTIVE ACTIO?!:
Further testing and investigation showed the 1cvel switch trip and alarm circuitrv to ba fully operable. The jumpers on the switch circuitry were t
Further testing and investigation showed the 1cvel switch trip and alarm circuitrv to ba fully operable. The jumpers on the switch circuitry were t
050k                                           )f,
050k
)f


        ^
. D l''
                  . D l'' 'AO 50-2k5h removed. Operators will be instructed in the proper method of actuating these level switches for future testing.
'AO 50-2k5h
^
removed. Operators will be instructed in the proper method of actuating these level switches for future testing.
FAILURE DATA:
FAILURE DATA:
The Five-Foot Condenser Pit Level Switches have performed satisfactorily in previous tests. A similar incident also occurred on June 13, 1974 in testing Unit I Five-Foot Condenser Pit Level Switches (Reference A,0,-
The Five-Foot Condenser Pit Level Switches have performed satisfactorily in previous tests. A similar incident also occurred on June 13, 1974 in testing Unit I Five-Foot Condenser Pit Level Switches (Reference A,0,-
Line 43: Line 50:
i e
i e
a a
a a
l i
l ii
i
)
  )
-,...}}
        - , . . .}}

Latest revision as of 04:26, 14 December 2024

AO 50-265/74-11,on 740621,condenser Pit 5 Ft Level Switch Failed to Actuate Control Room Annunciator.Caused by Failure to Fully Lift Level Switch Float Plunger During Testing
ML20084K622
Person / Time
Site: Quad Cities  
Issue date: 06/21/1974
From:
COMMONWEALTH EDISON CO.
To:
US ATOMIC ENERGY COMMISSION (AEC)
Shared Package
ML20084K617 List:
References
AO-50-265-74-11, NUDOCS 8305190498
Download: ML20084K622 (2)


Text

~

(O O

'O G

.0 REPORT hWBER: A0-50-.265/74-11 REPORT DATE: June-21, 1974 OCCURRE?;CE DATE: June 13, 1974 FACILITY: Quad Cities Nuclear Power Station Cordova, Illinois 61242 IDEUTIFIC ATION OF OCCURRENCE:

Condenser Pit Five-Foot Level Switch failed to actuate Control Room Annunciator during monthly testing.

CONDITIONS PRIOR TO OCCURRENCE:

1 Unit 2 Reacter in cold shutdown.

2 All three Unit 2 Circulating Water Pumps operating.

DESCRTW TON OF OCC m W CE:

Level Switch LS-2-4441-24A did not actuate the Control Room Annunciator when monthly surveillance of the Condenser Pit Five-Foot Level Switches was performed in accordance with Technical Specification 4.5.H.1.d.

This switch circuitry was jumpered in the tripped fail-safe condition oer

^

Technical Specification 3.5.H.2 A work request was imediately initiated to investigate and repair the apparent malibnetioning trip and alarm cir-cuitry.

DESIGNATION OF APPARE?"P CAUSE OF OCCURRE'!CE:

N.

4 The apparent cause of the failure of the surveillance test of LS-2-4441-24A to actuate the Control Room Annunciator is that the Level Switch Float Plunger was not fully lifted vertically during testing, thus not closing the switch contacts.

ANALYSIS OF OCCURRENCE:

Investigation indicates that no switch failure, and thus no occurrence, actually occurred. Therefore, this incident has no safety implications.

CORRECTIVE ACTIO?!:

Further testing and investigation showed the 1cvel switch trip and alarm circuitrv to ba fully operable. The jumpers on the switch circuitry were t

050k

)f

. D l

'AO 50-2k5h

^

removed. Operators will be instructed in the proper method of actuating these level switches for future testing.

FAILURE DATA:

The Five-Foot Condenser Pit Level Switches have performed satisfactorily in previous tests. A similar incident also occurred on June 13, 1974 in testing Unit I Five-Foot Condenser Pit Level Switches (Reference A,0,-

50-254/74-19).

1 4

i e

a a

l ii

)

-,...