ML20210P418
| ML20210P418 | |
| Person / Time | |
|---|---|
| Site: | 05200003 |
| Issue date: | 08/19/1997 |
| From: | WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP. |
| To: | |
| Shared Package | |
| ML20210P416 | List: |
| References | |
| NUDOCS 9708270111 | |
| Download: ML20210P418 (8) | |
Text
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DC Sources. Operating 3.8.1 3.8, ELECTRICAL POWER SYSTEMS 3.8.1 DC Sources. Operating LCO 3.8.1 The Division A. B. C. and D Class IE DC power subsystems shall be OPERABLE.
-APPLICABILITY:
MODES 1. 2. 3. and 4.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME 1
l A.
One DC electrical A.1-Restore DC electrical 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> power subsystem power subsystem to inoperable.
OPERABLE status.
B.
Two DC electrical B.1 Restore DC electrical 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> power subsystems power subsystem to inoperable.
OPERABLE status.
C.
Required Action and C.1 Be in H0DE 3.
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> associated Completion Time not met.
AND C,2 Be in MODE 4.
36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> 9708270111 970819 PDR ADOCK 05200003 A
PDRa M AP600.omoi..,ono.,
3.8 1 08/97 Amendment 0
. % i......o
?
Distribution Systems Operating 3.B.5 3.8, ELECTRICAL-POWERSYSTEMS 3.8.5 Distributir.. Systems - Operating LCO 3.8.5 The Division A. B. C and D AC and DC instrument and control bus electricci power distribution subsystems shall be
- OPERABLE, 4
APPLICABILITY:
MODES 1. 2, 3. and 4.
ACTIONS.
CONDITION REQUIRED ACTION COMPLETION TIME A.
One Division AC A.1 Restore AC instrunent 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> instrument and and control bus to control bus OPERABLE status.
=AND Inoperable.
12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> from discovery j
of failure to i
I meet the LCO 1
B.
One Division DC B.1 Restore DC electrical 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> electrical power power distribution distribution subsystem to OPERABLE AND subsystem inoperable, status.
12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> from discovery of failure to meet the LCO (continued) b AP600.oi.o,ono, 3.8 11 08/97 -Amendment-0 oon,.co
..oa
Distribution Systems Operating 3.8.5
~ ACTIONS (continued)
CONDITJON REQUIRED ACTION COMPLETION TIME C.
Two Divisions AC C.1 Restore AC instrument 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> instrument and and control bus to control bus
-0PERABLE status.
AND inoperable.
16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> from discovery of failure to meet the LCO.
l D.
Two Divisions DC D.1 Restore DC electrical 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />s-electeical power power distribution l
distribution subsystem to OPERABLE AND subsystem inoperable, status.
16 hours1.851852e-4 days <br />0.00444 hours <br />2.645503e-5 weeks <br />6.088e-6 months <br /> from discovery of failure to meet the LCO.
E..
Required Action and E.1 Be in H0DE 3.
6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> associated Completion Time not met.
AND E.2 Be in H0DE 5.
36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> F.
Two Divisions with F.1 Enter LC0 3.0.3.
Immediately inoperable distribu.
tion subsystems that result in a loss of safety function.
b AP600.on.a nm 3.8 12 08/97 Amendment 0 uo uu...u o
DC Sources Operating B 3.8.1
, BASES (cont.inued)
APPLICABILITY The Class IE DC electrical power sources are required to be OPERABLE in H0 DES 1, 2, 3, and 4 to ensure safe unit operation and to ensure that:
a.
Acceptable fuel design limits and reactor coolant pressure boundary limits are not exceeded as a result of j
A00s or abnormal transients: and b.
Adequate core cooling is provided, and containment integrity and other vital functions are maintained in the j
event of a postulated DBA.
Class 1E DC electrical power requirements for MODES 5 and G i
are addressed in the Bases for LCO 3.8.2, "DC Sources
- Shutdown."
ACTIDNS A.1 inoperable, the remaining Class 1E DC electricafstems is If one of the Class 1E DC electrical power subs power subsystems have the capacity to support a safe shutdown and J.
to mitigate all design basis accidents, based on j
conservative analysis.
Because of the passive system design and the use of fail safe components, the remaining Class 1E DC electrical power subsystems have the capacity to support a safe shutdown and to mitigate most DBAs following a subs 0quent worst case single failure.
The 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> Completion-Time is reasonable based on engineering judgement balancing the risks of operation without one DC subsystem against the risks of a forced shutdown. Additionally, the Completion Time reflects a reasonable time to assess plant status; attempt to repair or replace, thus avoiding an unnecessary shutdown: and, if necessary, prepare and effect an orderly and safe shutdown.
Inw+ A e
The installed spare battery bank and charger may be used to restore an inoperable Class 1E DC electrical power subsystem: however, all applicable Surveillances must be met by the spare equi ment used, prior to declaring the-subsystem OPERABLE.
(continued) h AP600 B 3.8 4 08/97 Amendment 0
-..o u..... w. m.oi.ov er m,
o Distribution Systems Opersting B 3.8.5 BASES ACTIONS A.1 (continued)
Because of the passive system design and the use of fail safe components, the remaining Class 1E AC instrument and control buses have the capacity to support i safe shutdown and to mitigate most design basis accidents following a subsequent worst case single failure. The 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> Completion Time is reasonable based on engineering judgement balancing the risks of operation without one AC instrument and control bus against the risks of a forced shutdown. Additionally, the Completion Time reflects a reasonable time to assess plant stctus: attempt to repair or replace, thus avoiding an unnecessary shutdown: and, if necessary, prepare and effect an orderly and safe shutdown.
This 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> limit is shorter than Completion Times allowed for most supported systems which would be without power.
Taking exception to LC0 3.0.2 for components without adequate DC Power, which would have Re Completion-Times shorter than 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, quired Actionis accepta of:
a.
The potential for decreased safety by requiring a change in unit conditions (i.e., requiring a shutdown) while allowing stable operations to continue; b.
The potential for decreased safety by requiring entry into numerous applicable Conditions and Required Actions for components without DC power and not providing 1
sufficient time for the operators to perform the-necessary evaluations and actions for restoring power to the affected division; and
- c. The potential for an event in conjunction with a single failure of a redundant component.
The 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> Completion Time takes into account the importance to safety of restoring the Class 1E AC instrument and control bus to OPERABLE status, the passive des: 1 of the ESF systems, the redundant capability afforded by the other OPERABLE Class IE AC instrument and control buses, and the low probability of a DBA occurring during this period which requires more than two OPERABLE AC instrument and control buses.
ln S er b h.
(continued) b AP600 B 3.8 27 08/97 Amendment 0 ootiu~,uo mem,o, orm, 1
Distribution Systems Operating B 3.8.5
' BASES ACTIONS A.1 (continued)
The second Completion Time for Required Action A.1
)
establishes a limit on the inaximum time allowed for any i
combination of requireo distribution subsystems to be inoperable during any single contiguous occurrence of failing to meet the LCO, If Co'idition A is entered while, for instance, a DC bus it, inoperable and subsequently restored OPERABLE, the 1.C0 may already have been not met for up to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. This could lead to a total of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />, since initial failure of the LCO, to restore the AC i
instrutant and control distribution system, At this time, a DC circ'Jit could again become inoperable, and AC instrument and con *rol distribution restored OPERABLE, This could continue indefinitely.
The Completion Time allows for an exception to the normal I
" time zero" for beginning the allowed outage time " clock."
This will result in establishing the ' time zero" at the time i
the LCO was initially not met, instead of the time Condition A was entered. The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Completion Time is aa acceptable limitation on this potential to fail to meet the LCO indefinitely, I
i With one Division of the Class 1E DC electrical power distribution subsystem inoperable, the remaining Divisions i
have the capacity to support a safe shutdown and to mitigate j-all-DBAs,- based on conservathe analysis.
Because of the passive system design and the use of l
fail safe components, the remaining Divisions have the capacity to support a safe shutdown' and to raitigate most design basis accidents followin a subsequent worst case sitigle failure. The 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> Com letion Time is reasonable based on engineering judgement alancing the risks of o>eration without one Division against the risks of a forced slutdown.
Additionally, the completion tinie reflects a o
reasonable time to assess plant status; attempt to repair or i
replace, thus avo'iing an unnecessary shutdown: and, if necessery, prepare and effect an orderly and safe shutdown.
nset C.
(continued) 4 h AP600 B 3.8 28 08/97 Amendment 0
- oo u.o..o.ow.os,o,o m er
_. - _ _. _ _. = _ _. _ _ _ _ _ _ _ _ _. ~ _ _ _
d j
Distribution Systems
-Operating B 3.8.5 l'ASES ACTIONS B.1 (continued)
~~
U This / hour limit is shorter than Completion Times allowed 1
for most supported systems which would be without power.
Taking exception to LCO 3.0.2 for components without adequate DC power, which would have Required Action Completion Times shorter than 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, is acceptable because of:
a.
The potential for decreased safety by requiring a change in unit conditions (i.e., requiring a shutdown) while i
allowing stable operations to continue:
b.
The potential for decreased safety by requiring entry into numerous applicable Conditions and Required Actions for components without DC power and not providing sufficient time for the operators to perform the necessary evaluations and actions to restore power to the i
affected division: and c.
The potential for an event in conjunction with a single failure of a redundant component, The second Completion Time for Required Action B.1 establishes a limit on the maximum time allowed for any combination of required distribution subsystems to be inoperable during any single contiguous occurrence of failing to meet the LCO.
If Condition B is entered while, for instance, an AC instrument and control bus is inoperable and subsequently returned OPERABLE. the LC0 may already have been not met for up to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. This could lead to a total of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, since initial failure of the LCO, to restore the DC distribution system.
At this time, an AC train could again become inoperable, and DC distribution restored OPERABLE. This could continue indefinitely.
This Completion Time allows for an exception to the normal
~
" time zero" for beginning the allowed outage time " clock."
This will result in establishing the " time zero" at the time i
the LC0 was initially not met, instead of the time Condition B was entered. The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Completion Time is an acceptable limitation on this potential to fail to meet the LC0 indefinitely.
(continued) h AP600 B 3.8 29 08/97 Amendment 0 AP01 techseecd4030805 r07 073197
AS N b' The 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> Con 1pletion Time is also consistent with the time specified for restoration of one (of four) Engineered Safety Features Actuation Cabinet (ESPAC) or Protection Logic. Cabinet (PLC) division (LCO 3.3.2, ESFAS Instrumentation).
Depending on the natere of the DC electrical power subsystem inoperability, one supported division ofinstrumentation could be considered inoperable. Inoperability of an ESPAC or PLC is similar to loss of one DC electrical power subsystem. In both cases, actuation of the safety functions associated with one of the four subsystems / divisions may no longer be available.
IC5 eft SL '-
The 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> Completion Time is also consistent with the time specified for restoration of one (of four) Engineered Safety Features Actuation Cabinet (ESFAC) or Protection Logic Cabinet (PLC) digigf$chg3 2 ESFASfnstrumenta th$perability, one O
j Depending on the nature of the M - n- -
supported division ofinstrumentation could ba co of an ESFAC or PLC is similar to loss of one Mgipg igp'erable fugrab lig^*
q
-..... n 7.L,,,,,,,,, M n both cases, actuation of the safety functions associated with one of the four subsystema/ divisions mr.y no longer be available.
IBMrt O'.
The 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> Completion Time is also consistent with the time specified for restoration of one (of four) Engineered Safety Features Actuation Cabinet (ESPAC) or Protection Logic Cabinet (PLC) division (LCO 3.3.2 ('s/sTm ino SFAS Instrumentation).
Depending on the nature of the DC electrical powe/M supported division ofinstrumentation could be considered inopera t Inoperability of an ESFAC or PLC is similar to loss of one DC electrical power $Ws both cases, actuation of the safety functions associated with one of the four subsystems / divisions may no longer be available.
.. =
= -.
.