Text

Proposed Tech Specs,Consisting of Suppl 10 to Change Request 93-16 Re Conversion to Improved TS
	ML20085D786
Person / Time
Site:	Peach Bottom
Issue date:	06/07/1995
From:	; PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	;
Shared Package
ML20085D783	List: ML20085D780; ML20085D786;
References
	NUDOCS 9506160348
	Download: ML20085D786 (53)
	v • d • e

k1' )

l AC Sources-Operating 3.8.1

[' 3.8 ELECTRICAL POWER SYSTEMS I

3.8.1 AC Sources-Operating LC0 3.8.1 The following AC electrical ower sources shall be OPERABLE: .

.C. w :s s

a. Two qualified circuit 3) e tween the offsite transmission network and the Unit 2 onsite Class IE AC Electrical Power stribution System; i C L+ 3

b. Four sel generators (DGs) capable of supplying the .

Unit nsite Class IE AC Electrical Power Distribution System; p4

c. The qualified circuit (s) between t offsite transmission network and the Unit )onsite Class IE AC ,

electrical power distribution subsystem (s) needed to '

gC 3 7tirppboFCthe UditD T powered equipment required to be ;

/0PERABLE by ~LCO LLLJ. ". Standby _. Gas Treatment (SGT)

/

/ System,"(C03.7.3," Emergency _lleatSinkMn'd LCO 3.8.4, Dc sources-Operating"; and k. La 2.

./ g 4, u .+ s .

- 'y

d. The DG(s) capable of supplying the Unit 3 onsite Class 1E AC electrical powfr distribution subsystem (s) needed ;

,_..x. to support the Unit (J) powered e.quipment required to be :

OPERABLE by LCO 3.5.4.3,(t.C0~3.7.31 and LCO 3.8.4. t

\

L LIz.

&_D 4 DES 1, 2, and 3. C LA 3 m an. z, !

APPLICABILIT). g 3,9,4

% .L. W:t 5 h Lcu 3. t s . t , "( . k s .M A 4-ehdt- /

b; LL ( o M 5p.L ,' ;

cun g m

u hdht

Leo M I, E"

oy y s.d ,' ;

t uc us ,u g;, (n he\ W

O " V i - ,,

j

,/.

4G l.S% ( t4C RE h $$)'0, s :

Aa- E I b

PBAPS UNIT 2 3.8-1 Amendment f

9506160348 950607 PDR ADOCK 05000277 <

P PDR

w. . - __ _ _ _ _ _ . . . .

F l AC Sources--Operating 3.8.1 SURVEILLANCE REQUIREMENTS 3 c, w.\s -

NOTE--------------------- --------------

SR 3.8.1.1 through SR 3.8.1.20 are applicab only to the Unit 2 AC sources.

SR 3.8.1.21 is applicable only to the Unit 3 AC sources.

......_____..........._________..__....... 1..__..____________...____________

2)y w SURVEILLANCE FREQUENCY SR 3.8.1.1 Verify correct breaker alignment and 7 days indicated power availability for each offsite circuit.

SR 3.8.1.2 -------------------NOTES-------------------

1. Performance of SR 3.8.1.7 satisfies this SR.

2. All DG starts may be preceded by an engine prelube period and followed by a warmup period prior to loading.

3. A modified DG start involving idling and gradual acceleration to synchronous speed may be used for this SR as recommended by the manufacturer. l When modified start procedures are not used, the time, voltage, and frequency tolerances of SR 3.8.1.7 must be met.

4. A single test at the specified i Frequency will satisfy this Surveillance for both units.

Verify each DG starts from standby 31 days conditions and achieves steady state '

voltage a: 4160 V and s 4400 V and frequency 2: 58.8 Hz and s 61.2 Hz.

(continued) l' P8APS UNIT 2 3.8-6 Amendment

(-

AC Sources-0perating 3.8.1 SURVEILLANCE REQUIREMENTS (continued) _

SURVEILLANCE FREQUENCY SR 3.8.1.3 -------------------NOTES-------------------

1. DG loadings may include gradual loading as recommended by the manufacturer.

2. Momentary transients outside the load range do not invalidate this test.

3. This Surveillance shall be ccnducted on only one DG at a time.

4. This SR shall be preceded by and immediately follow, without shutdown, a successful performance of SR 3.8.1.2 or SR 3.8.1.7.

5. A single test will satisfy this Surveillance for both units i' h synchronization to the Uni 2 kV GM3 emergency bus for one perio c t and synchronization to the Unit _ 4 kV emergency bus during the next periodic test. However, if e test is not performed on Unit 3 then the test shall e performe nchronized to the Unit 2 kV emergen bus.

Verify each DG is synchronized and loaded 31 days and operates for 2 60 minutes at a load 2 2400 kW and s 2600 kW.

SR 3.8.1.4 Verify each day tank contains 2 200 gal of 31 days fuel oil.

SR 3.8.1.5 Check for and remove accumulated water from 31 days each day tank.

(continued)

PBAPS UNIT 2 3.8-7 Amendment

AC Sources--Operating 3.8.1 SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.8.1.20 -------------------NOTES-------------------

1. All DG starts may be preceded by an engine prelube period.

2. A single test at the specified frequency will satisfy this Surveillance for both units.

Verify, when started simultaneously from 10 years standby condition, each DG achieves, in s 10 seconds, voltage 2: 4160 V and frequency at 58.8 Hz.

f_ u_a 3 SR 3.8.1.21 ---------

.-------NOTE--------------------

When Unit 3 is in MODE 4 or 5, or moving irradiated fuel assemblies in be secondary containment, the Note to Unit 3)SR 3.8.2.1 is applicable. - f, L a 3 g 33 c1G,La3 For uired Unit AC sources, the S e of In accordance Unit > Specification 3.8.1, exc 41 G. Lg+ with applicable SR 3.8.1.8 (when only one Unit 3 offs te SRs circuit is required), SR 3.8.1. 2, SR 3.8.1.13, SR 3.8.1.17, SR 3.8.1.18 (ECCS load block requirement only), and SR 3.8.1.19 are applicable.

PBAPS UNIT 2 3.8-18 Amendment

AC Sources-Shutdown 3.8.2 3.8 ELECTRICAL POWER SYSTEMS 3.8.2 AC Sources-Shutdown LC0 3.8.2 The following AC electrical poy r sources shall be OPERABLE:

3 4, L t 3

a. One qualified circuit . tween the offsite transmission network and the Unit 2 onsite Class IE AC electrical power distribution su system (s) required by LCO 3.8.8,

" Distribution Systems-Shutdown"; f g y,3

b. Two DGs each capable of supplying one Uni 2 onsite Class IE AC electrical power distribution subsystem required by LCO 3.8.8; (5) G 6.:ta

c. One qualified circuit bTe ween the offsite transmission network and the UnitU3 onsite Class IE AC electrical

.G, Le a N

{powerdistributionsubsystem(s)neededtosupportthe UnitTf/ powered equipment required to be OPERABLE by LC0 3.6.4 " Standby Gas Treatment [SGT) System,",and

" ~LC'0 378!$ [.3DFSources-Shutdown"; and

~

^

tco g,, 3t ,.q" e, @E.""y^'y I d. (One DG capable of supplying one Unit 3 onsite Class 1 V ," g w ( n atcg) ) AC electrical power distribution subsystem needed to

, / support the Unit 3 powered equipment required to be fOPERABLEby: '

4, u . + 3

[ I 1 . LC0 3.6.4.3.

j 1m LC0 3.8 APPLICABILITY: H0 DES 4 and 5, During movement of irradiated fuel assemblies in the secondary containment.

% M(n co p cAle J f

%gp 3;g eu sh 36 / <a ef

2. re e, d 4e la m2h Q W:4 g es . < < 8 e ip % g Leo R A 5, Lco n4' cof Ro 37.5

/

./

b) d

[, b4b 3 J

i l

(.

~

l PBAPS UNIT 2 3.8-19 Amendment

I, AC Sources--Shutdown !

3.8.2 i SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.8.2.1 -------------------NOTE--------------------

The following SRs are not required to be performed: SR 3.8.1.3, SR 3.8.1.9 through SR 3.8.1.11, SR 3.8.1.13 through SR 3.8.1.16, SR 3.8.1.18, and SR 3.8.1.19. ,

s JC L.A 3 For required Unit 2 AC sources the SRs of In accordance Specification 3.8. , except SR 3.8.1.8, with applicable SR 3.8.1.17, and SR 3.8.1.20, are SRs applicable.

(f)t; L t3 SR 3.8.2.2 ----------

NOTE-------------------- ,

When Unit (3)inot in MODE 1, 2, or 3, the Note to Unit 3 SR 3.8.2.1 is applicable.

c. (m33 41 JL L-a s For utred Unit 3 AC sources, the SRs of In accordance Unit Specification 3.8.1, exc t al 4. L t with applicable SR 3.8.1.8 (when only one Unit 3s o ffs te 3 SRs circuit is required), SR 3.8.1. 2, SR 3.8.1.13, SR 3.8.1.17, SR 3.8.1.18 (ECCS load block requirement only), SR 3.8.1.19, and SR 3.8.1.20, are applicable.

l l

PBAPS UNIT 2 3.8-23 Amendment

- - J

DC Sources-Operating 3.8.4 ,

3.8 ELECTRICAL POWER SYSTEMS 3.8.4 DC Sources-Operating i

LC0 3.8.4 The following DC electrical power subsystems shall be OPERABLE: 3 g g3 l

a. Unit 2 Division I and Division II DC electrical power i subsyst s; and :

4. Lt 3 :

b. Unit ivision I and Division II DC electrical power. !

subsystems.

APPLICABILITY: MODES 1, 2, and 3. l

(

ACTIONS ,

CONDITION REQUIRED ACTION COMPLETION TIME j c.. L,.a 3 :

A. One Unit DC -------------NOTE------------ l' electric power Enter applicable Conditions subsystem inoperable and Required Actions of LC0 ,

due to performance of 3.8.7, " Distribution ,

SR 3.8.4.7 or Systems--Operating," when 4 g,3 i SR 3.8.4.8. Condition A results in !

de-energization of a Unit o 4 kV emergency bus or de-energization of a Unit 3 4M3 DC bus. ;

A.1 Restore Unit 3 DC 7 days electrical power subsystem to OPERABLE i status. '

(continued)

PBAPS UNIT 2 3.8-27 Amendment i

DC Sources-Operating 3.8.4 i

SURVEILLANCE REQUIREMENTS

, & L. 3

....___.___.....___......._____------NOTE--------------------- ---------------

SR 3.8.4.1 through SR 3.8.4.8 are applicable only to the Uni 2 DC electrical power subsystems. SR 3.8.4.9 is applicable only to the Unit 3 DC electrical power subsystems. A L L'u SURVEILLANCE FREQUENCY l

SR 3.8.4.1 Verify battery terminal voltage is -----NOTE------

2123.S V on float charge. The 7 day i Frequency is l not applicable if the battery l is on equalize charge or has been on equalize charge at any time during the I previous 1 day.

7 days AND 14 days SR 3.8.4.2 Verify no visible corrosion at battery 92 days terminals and connectors. l QR Verify battery connection resistance is s 40 E-6 ohms.

SR 3.8.4.3 Verify battery cells, cell plates, and 12 months racks show no visual indication of physical damage or abnormal deterioration. )

(continued)

PBAPS UNIT 2 3.8-29 Amendment

DC Sources--Operating 3.8.4 i

l SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY f,,, w*.h SR 3.8.4.9 ----------

NOTE--------------------

When Unit 3 is in MODE 4 or 5, or moving irradiate fuel assemblies in e secondary containment, the Note to Unit 3 SR 3.8.5.1 is applicable. fl g, g_3 3

................. .x........ ............

J2 p. tma 3 for required Unit 3 DC elect ical power In accordance subsystems, the SRs of Unit Specification with applicable 3.8.4 are applicable. J1 g, u;,, s SRs an - - .

i r

h PBAPS UNIT 2 3.8-32 Amendment

1

'l DC Sources--Shutdown :

3.8.5 3.8 ELECTRICAL POWER SYSTEMS ;

3.8.5 DC Sources--Shutdown :

4 LC0 3.8.5 The following DC electrical power subsystems shall be .

OPERABLE: f, u;t :5 l

a. UnitWDC electrical power subsystems needed'to support ,

the DC electrical power distribution subsystem (s) :

required by LC0 3.8.8, " Distribution Systems--Shutdown";

and ' 33 J2 l

b. Unit DC electrical power subsystems needed to support the DC electrical power distribution subsystem (s) ;

required by LC0 3.8.8, " Distribution Systems--Shutdown." j MODES 4 and 5, !

APPLICABILITY:

During movement of irradiated fuel assemblies in the ;

secondary containment. !

ACTIONS

NOTE-------------------------------------

LC0 3.0.3 is not applicable.

CONDITION- REQUIRED ACTION COMPLETION TIME A. One or more required A.1 Declare affected Immediately DC electrical power required feature (s) subsystems inoperable. inoperable.

QB A.2.1 Suspend CORE Immediately ALTERATIONS.

AND (continued)

PBAPS UNIT 2 3.8-33 Amendment

r DC Sources-Shutdown 3.8.5 SURVEILLANCE REQUIREMENT:.,

SURVEILLANCE FREQUENCY SR 3.8.5.1 -------------------NOTE--------------------

The following SRs are not required to be performed: SR 3.8.4.7 and SR 3.8.4.8.

ForrequiredUnit(2/DCelectricalpower In accordance subsystems, the following SRs are with applicable applicable: SRs SR 3.8.4.1 SR 3.8.4.4 SR 3.8.4.7 SR 3.8.4.2 SR 3.8.4.5 SR 3.8.4.8.

SR 3.8.4.3 SR 3.8.4.6 f g 4, L a 3 SR 3.8.5.2 -------- b- ------NOTE--------------------

When Unit 3 is in MODE 4 or 5, or moving irradiated fuel assemblies in e secondary containment, the Note to Unit 3 SR 3.8.5.1 is applicable. ggu For required Unit DC elect ical power In accordance subsystems, the SRs of Unit 3 Specification with applicable 3.8.4 are applicable. g 4, y 3 SRs PBAPS UNIT 2 3.8-35 Amendment

Distribution Systems-Operating 3.8.7 3.8 ELECTRICAL POWER SYSTEMS 3.8.7 Distribution Systems-0perating LC0 3.8.7 The following AC and DC electrical power distribution subsystems shal be OPERABLE:

3

a. Unit ision I and Division II AC and DC electrical power istribution subsystems; and

b. Unit (3)AC and DC electrical power distribution subsystems needed to support equipment required to be OPERABLE by LC0 3.4.7, " Residual Heat Removal (RHR)

Shutdown Cooling System-Hot Shutdown," LC0 3.5.1, "ECCS-Operating," LCO 3.6.2.3, "RHR Suppression Pool Cooling," LCO 3.6.2.4, "RH3 Suppression Pool Spray,"

LC0 3.6.3.1, " Containment Atmospheric Dilution (CAD)

System," LC0 3.6.4.3, " Standby Gas Treatment (SGT) i System," LCO 3.7.1, "High Pressure Service Water (HPSW) l System," LC0 3.7.2, " Emergency Service Water (ESW) '

System and Normal Heat Sink," LC0 3.7.3, " Emergency Heat Sink," and LC0 3.8.1, "AC Sources-_0parating "

i

' uo h 4 ," S c^ C + I E"^ l Ear) W

~^

APPLICABILITY: MODES 1, 2, and 3. l y

& k.: t 5 3..

k P8APS UNIT 2 3.8-40 Amendment

Distribution Systems-Operating 3.8.7 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME L w..o A. One ore required -------------NOTE------------

Unit AC electrical Enter applicable Conditions power distribution and Required Actions of LC0 subsystems inoperable. 3.8.4, "DC Sources-Operating," when Condition A results in a de-en gization of a required Unit 3 125 V battery charger. '

.... w..____ ...__.....____

G 6.15 A.1 Rest po required 7 days Unitu/AC electrical power distribution subsystem (s) to

. [v -

OPERABLE status.

(" .-

- n

(@ 4. un QdLc,wn B. One ired Uni 3 DC B.1 Restore Unit 3 DC 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months electrical power electrical power distribution subsystem distribution inoperable, subsystem to OPERABLE status.

m _

(.9) 4; u_.o g, u C. OneUnit(2)AC C.1 Restore UnitLP,)AC 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months !

electrical power electrical power ,

distribution subsystem distribution MQ l inoperable. subsystem to OPERABLE l' status. 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months from discovery of failure to meet LC0 3.8.7.a i

(continued)

PBAPS UNIT 2 3.8-41 Amendment

Distribution Systems--Operating 3.8.7 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME

/d & u s 3 a w.3 D. One Unit DC D.1 Restore Unit DC 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months electrica power electrical power distribution subsystem distribution aHQ inoperable. subsystem to OPERABLE status. 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months from discovery of failure to meet LC0 3.8.7.a E. Required Action and E.1 Be in MODE 3. 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months associated Completion Time of Condition A, AND B, C, or D not met.

E.2 Be in MODE 4. 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months F. Two or more inoperable F.1 Enter LC0 3.0.3. Immediately electrical power distribution subsystems that result in a loss of function.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.8.7.1 Verify: 7 days

a. Correct breaker alignments to required AC electrical power distribution subsystems; and

b. Indicated power availability to required AC and DC electrical power distribution subsystems.

PBAPS UNIT 2 3.8-42 Amendment

Distribution Systees-Shutdown 3.8.8 3.8 ELECTRICAL POWER SYSTEMS 3.8.8 Distribution Systems-Shutdown LC0 3.8.8 The necessary portions of the following AC and DC electrical power dis r- bution subsystems shall be OPERABLE:

3 4, L.

3

a. Unit 2 AC and DC electrical power distribution

, subsystems needed to support equipment required to be OPE ptEg agd

b. Unit l AC and DC electrical power distribution subsystems needed to support equipment required to be OPERABLE by LC0 3.4.8, " Residual Heat Removal (RHR)

Shutdown Cooling System-Cold Shutdown," LCO 3.5.2, "ECCS-Shutdown," LC0 3.6.4.3, " Standby Gas Treatment (SGT) System," LC0 3.8.2, "AC Sources-Shutdown,"

LCO 3.9.7, "RH -High Water Level," and LC0 3.9.8, "RHR-Low Wate Level."

.(co 3J4, "Incin Cor.bol Rwm 8"T*'I venFlohen (mcacyl Sy*mi d APPLICABILITY: MODES 4 and 5, O L 43 During movement of irradiated fuel assemblies in the secondary containment. 1 ACTIONS

NOTE-------------------------------------

LC0 3.0.3 is not applicable.

CONDITION REQUIRED ACTION COMPLETION TIME A. One or more required A.1 Declare associated Immediately AC or DC electrical supported required power distribution feature (s) subsystems inoperable. inoperable.

98 A.2.1 Suspend CORE Immediately ALTERATIONS.

l AND (continued)

PBAPS UNIT 2 3.8-43 Amendment

AC Sources-Operating B 3.8.1 ,

BASES BACKGROUND through the 13.2/4.16 kV emergency auxiliary transformer (continued) no. 3. In addition, the alternate source can only be used to meet the requirements of one offsite circuit. A detailed description of the offsite power network and circuits to the onsite Class IE ESF buses is found in the UFSAR, Sections 8.3 and 8.4 (Ref. 2).

A qualified offsite circuit consists of all breakers, transformers, switches, interrupting devices, cabling, and controls required to transmit power from the offsite transmission network to the onsite Class IE emergency bus or buses.

Either of the two qualified circuits to the offsite power network can provide power to any of the four 4 kV emergency buses using interlocked circuit breakers. A loss of power or degraded voltage on a 4 kV emergency bus causes an automatic transfer to the alternate qualified circuit and, therefore, different offsite source of power. (See Bases for LC0 3.3.8.1, Loss of Power (LOP) Instrumentation). A loss of power or significantly degraded voltage on an emergency bus also disconnects all loads from that bus.

When the 4 kV emergency bus voltage returns to > 95% of nominal, a relay associated with each 4 kV emergency bus provides a permissive that allows individual timers to sequentially load the 480 V emergency load center and other essential loads including the low pressure ECCS pumps, if an accident signal is present. (See Bases for LC0 3.3.5.1, Emergency Core Cooling Syst .( E ) Instrumentation).

d ' C L,a 5 A description of the Unit 3 off e power sources is provided in the Bases for ni 3 LC0 3.8.1, "AC Sources-Operating." The description is identical with the exce i that the two offsite circuits provid .w er to the Uni 3 4kVemergencybuses(i.e.,eaAhUni offsite circuit s I;.t t3 common to its respective Unit (3Jffsite :ircuit except for the 4 kV emergency bus feeder b akers). -

d u3 The onsite standby power sour or the four 4 kV emergency buses in each unit consists of four DGs. The four DGs provide onsite standby power for both Unit 2 and Unit 3.

Each DG provides standby power to two 4 kV emergency buses-one associated with Unit 2 and one associated with Unit 3.

A DG starts automatically on a loss of coolant accident (LOCA) signal (i.e., low reactor water level signal or high drywell pressure signal) from either Unit 2 or Unit 3 or on (continued)

PBAPS UNIT 2 B 3.8-2 Revision 0 I

i

1 AC Sources-Operating B 3.8.1 BASES (continued)

APPLICABLE The initial conditions of DBA and transient analyses in the SAFETY ANALYSES UFSAR, Chapter 14 (Ref. 4), assume ESF systems are OPERABLE.

The AC electrical power sources are designed to provide sufficient capacity, capability, redundancy, and reliability to ensure the availability of necessary power to ESF systems so that the fuel, Reactor Coolant System (RCS), and containment design limits are not exceeded. These limits are discussed in more detail in the Bases for Section 3.2, Power Distribution Limits; Section 3.5, Emergency Core Cooling Systems (ECCS) and Reactor Core Isolation Cooling (RCIC) System; and Section 3.6, Containment Systems.

The OPERABILITY of the AC electrical power sources is consistent with the initial assumptions of the accident .

analyses and is based upon meeting the design basis of the unit. This includes maintaining the onsite or offsite AC sources OPERABLE during accident conditions in the event of: ,

a. An assumed loss of all offsite power or all onsite AC power; and

b. A worst case single failure.

AC sources satisfy Criterion 3 of the Ni!C Policy Statement.

LC0 Two qualified circuits between the offsite transmission network and the onsite Class IE Distribution System'and four cu$ separate and independent DGs ensure availability of the (LkM required power to shut down the reactor and maintain it in a b '" .

safe shutdown condition after an abnormal __ operational @W 3 transient or a postulated DB_A6 addition, since

[D r.si equlp)mentrequiredbyUnit(,2)ispoweredfromU sou g

(i.e. Standby Gas Treatment'(SGT) System, eniEWncy heapg u.z s

-p u z ' csiiirualifiesLcircuit(s) componen_ty,fand etween the Unil l25 VDC battery "]char

@ transmission offsite q network and the Unit bnsite Class IE AC electrical power .

distribution subsyst s)neededtosupportthisequipment I t, v 3 must also be OPERABLE. 2. ,c v 3 A qualified Unit fksItVckrcuitconsistsoftheincoming Dqtlb ga hsg breaker and disconnect to the startup and emergency j

)

A c,3 ,i 6 auxiliary transformer, the respective circuit path to the ,

emergency auxiliary transformer, and the circuit path to b7] g* three Unit 2 4 kV emergency buses including feeder breakers W 7)G u 3 (continued)

PBAPS UNIT 2 B 3.8-4 Revision 0

AC Sources-Operating i B 3.8.1 ;

3 BASES O LC0 to t three Uni 4 kV emergency buses. A qualified (continued) Unit offsite circuit's requirements are the same as the ;

Unit circuit's requirements, except that th rcuit_ ,

"3 41 ing the feeder breakers, is to the Unit 4 kV ;

4, L, 3 emergency buses required to be OPERABLE by LC 3.8.7,

" Distribution Systems-0perating." Each offsite circuit must be capable of maintaining rated frequency and voltage,. >

and accepting required loads during an accident, while connected to the emergency buses.

Each DG must be capable of starting, accelerating to rate speed and voltage, and connecting to its respective Unit 2 8 4 kV emergency bus on detection of bus undervoltage.

sequence must be accomplished within 10 seconds. .Each DG Th s g }g must also be capable of accepting required loads within the assumed loading sequence intervals, and must continue to operate until offsite power can be restcred to the emergency buses. These capabilities are required to be met from a ,

variety of initial conditions, such as DG in standby with the engine hot and DG in standby with the engine at ambient ;

condition. Additional DG capabilities must be demonstrated ;

to meet required Surveillances, e.g., capability of the DG i to revert to standby status on an ECCS signal while ,

operating in parallel test mode. Proper sequencing of loads, including tripping of all loads, is a required j function for D P RABI TY. 3 4y3 In addition quipment required by Unit 2 is '

powered f o,m Uni sources, the DG(s) capable of supplying the Unit 3 nsit ass IE AC electrical power distribution subsystem s) needed to support this equipment must be ;

OPERABLE. The OPERABILITY requirements for these DGs are .

the same as described above, except that each required, must be capable of connecting to its respective UnitL3)4 kV 4M i emergency bus. (In addition, the Unit O3 ECCS initiation S logic SRs are not applicable, as descri ed in SR 3.8.1.21 Bases.) g The AC sources must be separate and independent (to the extent possible) of other AC sources. For the DGs, the separation and independence are complete. For the offsite AC sources, the separation and independence are to the ;

extent practical. A circuit may be connected to more than ;

one 4 kV emergency bus division, with automatic transfer ,

capability to the other circuit OPERABLE, and not violate (continued)

PBAPS UNIT 2 B 3.8-5 Revision 0 I

AC Sources-Operating B 3.8.1

-- BASES ACTIONS ftd (continued)

Condition G corresponds to a level of degradation in which !

redundancy in the AC electrical power supplies has been !

lost. At this severely degraded level, any further losses in the AC electrical power system may cause a loss of function. Therefore, no additional time is justified .for continued operation. The unit is required by LCO 3.0.3 to

commence a controlled shutdown.

SURVEILLANCE The AC sources are designed to permit inspection and REQUIREMENTS testing of all important areas and features, especially those that have a standby function, in accordance with UFSAR, Section 1.5.1 (Ref. 7). Periodic component tests are supplemented by extensive functional tests during refueling outages (under simulated accident conditions). The SRs for- '

demonstrating the OPERABILITY of the DGs are consistent with the recommendations of Regulatory Guide 1.9 (Ref. 3),

Regulatory Guide 1.108 (Ref. 8), and Regulatory Guide 1.137 (Ref. 9). 3 g g3 As Noted at the beginning of the SRs, SR 3.8 .1~through {

SR 3.8.1.20 are applicable only to the Unit 2 AC sources and ;

SR 3.8.1.21 is applicable only to the Unit AC sources.

z A tut 3 Where the SRs discussed herein specify voltag and frequency :

tolerances, the following summary is applicable. The minimum steady state output voltage of 4160 V corresponds to the minimum steady state voltage analyzed in the PBAPS emergency DG voltage regulation study. This value allows for voltage drops to motors and other equipment down through the 120 V level. The specified maximum steady state output voltage of 4400 V is equal to the maximum steady state operating voltage specified for 4000 V motors. It ensures that for a lightly loaded distribution system, the voltage ;

at the terminals of 4000 V motors is no more than the maximum rated steady state operating voltages. The specified minimum and maximum frequencies of the DG are 58.8 Hz and 61.E Hz, respectively. These values are equal to i 2% of the 60 Hz nominal frequency and are derived from the recommendations found in Regulatory Guide 1.9 (Ref. 3). -i (continued)

\

v PBAPS UNIT 2 B 3.8-17 Revision 0 o -

, ,-- w. -

AC Sources-0perating )

B 3.8.1 ;

i BASES ;

SURVEILLANCE SR 3.8.1.3 (continued) :

REQUIREMENTS !

The normal 31 day Frequency for this Surveillance is !

consistent with Regulatory Guide 1.9 (Ref. 3). l Note 1 modifies this Surveillance to indicate that diesel engine runs for this Surveillance may include gradual loading, as recommended by the manufacturer, so that~

mechanical stress and wear on the diesel engine are ,

minimized.

Note 2 modifies this Surveillance.by stating that momentary transients because of changing bus loads do not invalidate this test. Similarly, momentary power factor transients i above the limit do not invalidate the test. ,

Note 3 indicates that this Surveillance should be conducted on only one DG at a time in order to avoid common cause failures that might result from offsite circuit or grid perturbations. ;

Note 4 stipulates a prerequisite requirement for performance of this SR. A successful DG start must precede this test to credit satisfactory performance. 4us !

To minimize testing of the DGs ote 5 allows a single test (instead of two tests, one fo each unit) to satisfy the requirements for both unit with the DG synchronized to th 4kVemergencybusofUnit@s.for one periodic t c2 synchronized to the 4 kV emergency bus of Uni 3 uring the next periodic test. This is allowed since the main purpose 4 U 3 of the Surveillance, to ensure DG OPERABILITY, is still '

being verified on the proper frequency, and each unit's breaker control circuitry, which is only being tested every l second test (due to the staggering of the tests), l historically have a very low failure rate. If the DG fails one of these Surveillances, the DG should be considered !

inoperable on both units, unless the cause of the failure n can be directly related to only one unit. In tion i c* th t is scheduled to be performed on Uni and the Uni TS allowance that provides exception o performing N * '

b M5 the t is used (i.e., when Uni is in MODE 4 or 5, or l moving irradiated fuel assemb s the secondary l containment, the Note to Unit 3 SR 3.8.2.1 provides an exception to performing this est) hen the test shall be l performed synchronized to th Unit' 4 kV emergency bus.

Ied L M3 (continued) caa3v)g (a G.:t 3 PBAPS UNIT 2 B 3.8-20 Revision 0

AC Sources-Operating B 3.8.1 BASES SURVEILLANCE SR 3.8.1.6 (continued)

REQUIREMENTS the fuel oil transfer pump is OPERABLE, the fuel oil piping system is intact, the fuel delivery piping is not obstructed, and the controls and control systems for automatic fuel transfer systems are OPERABLE.

The Frequency for this SR is 31 days because the design of the fuel transfer system is such that pumps operate automatically in order to maintain an adequate volume of fuel oil in the day tanks during or following DG testing and proper operation of fuel transfer systems is an inherent part of DG OPERABILITY.

SR 3.8.1.8 Transfer of each 4 kV emergency bus power supply from the normal offsite circuit to the alternate offsite circuit demonstrates the OPERABILITY of the alternate circuit distribution network to power the shutdown loads. The 24 month Frequency of the Surveillance is based on '

engineering judgment taking into consideration the plant conditions required to perform the Surveillance, and is intended to be consistent with expected fuel cycle lengths.

Operating experience has shown that these components will pass the SR when performed on tne 24 month Frequency. -

Therefore, the Frequency war concluded to be acceptable from a reliability standpoint.

This SR is modified by a Note. The reason for the Note is that, during operation with the reactor critical, performance of this SR could cause perturbations to the electrical distribution systems that could challenge 3 continued steady state operation and, as a result, plant safety systems.- This Surv lance tests the applicable lWiii_asyciatedliWUliT 2. The comparable test specified 4W3 - in Un tions tests the applicable M lbgTc_itU3TechnicalSpecif associated _with_ Unit 3 Consequently, a test must be yS performed within the specified Frequency for each unit. As the Surveillance represents separate tests, the Note c y' specifying the restriction for not performing the test while 3 v the unik-4s in MODE 1, 2, or 3 does not havq applicability to UnitL3) The Note only applies to Unit / 2) tJyls the Unit Surveillance shall not be performed with ~it U2 in MODE 1, 2, or 3. Credit may be taken for unplann d ev nts that a3 satisfy this SR. - ,

(S 3 r, u 3 (continued)

PBAPS UNIT 2 B 3.8-22 Revision 0

AC Sources-Operating B 3.8.1 i

BASES SURVEILLANCE SR 3.8.1.11 (continued)

REQUIREMENTS heat removal function are not desired to be realigned to the ECCS mode of operation. In lieu of actual demonstration of the connection and loading of these loads, testing that ;

adequately shows the. capability of the DG system to perform these functions is acceptable. This testing may include any series of sequential, overlapping, or total steps so that the entire connection.and loading sequence is verified.

The Frequency of 24 months takes into consideration plant conditions' required to perform the Surveillance, and is intended to be consistent with expected fuel cycle lengths.

This SR is modified by two Notes. The reason for Note 1 is to minimize wear and tear on the DGs during testing. For the purpose of this. testing, the DGs shall be started from standby conditions, that is, with the engine coolant and oil being continuously circulated and temperature maintained consistent with manufacturer recommendations. The reason >

for Note 2 is that performing the Surveillance would remove .

a required offsite circuit from service, perturb the !

electrical distribution system, and challenge safety ,

stemsu TM s Survei ance tests the applicable logic M3 ,3 sassociat 4 with Unit 2 The comparable test specified in !

Unit 3 echnical peci ions tests the applicable _ 4 p -

S logic associated with Unit onsequently, a teit must be .

performed within the specif e Frequency for each unit. As the Surveillance represents separate tests, the Note i specifying the restriction for not performing the test while l

, X the uni bis in MODE 1, 2, or 3 does not h applicability FIo'Unii(_3) The Note only applies to Unit th the Unit

(,4 Surveilrances shall not be performed with Unit 2 in MOD i 2, or 3. Credit may be taken for unplan d eve s that. '

satisfy this SR.

S O 4 6u 4 Lt3 SR 3.8.1.12 Consistent with Regulatory Guide 1.9 (Ref. 3),

paragraph C.2.2.5, this Serve 111ance demonstrates that the DG automatically starts and achieves the required voltage and frequency within the specified time (10 seconds) from the design basis actuation signal (LOCA signal) and operates for a 5 minutes. The 5 minute period provides sufficient time to demonstrate stability. SR 3.8.1.12.d and (continued)

PBAPS UNIT 2 B 3.8-26 Revision 0 2

AC Sources-Operating B 3.8.1 BASES SURVEILLANCE SR 3.8.1.16 (continued)

REQUIREMENTS

~ ,_Surv lance tests the applicable logic associated Uni 2 The comparable test specified in the Uni Techn cal Specificati ns tests the applicable logic U3

/ - associate _d_with_ Uni 3; Consequently, a test must be 2 As

&'.;r 3 f;mjperfo_rmedwithinthespecifiedFrequencyforeachunit.

the Surveillance represents separate tests, the Note t

specifying the restriction for not performing the test while N theunitdsinMODE1,2,or3doesnoth applicability O 7o Unit (J4 The Note only applies to Uni th s the Uni Surveillances shall not be performed with nit 2, or 3. Credit may be taken for unplan d eve s inthat MODE 1, 4 f satisfy this SR. -

d SR 3.8.1.17 SQ Consistent with Regulatory Guide 1.9 (Ref 3),

paragraph C.2.2.13, demonstration of the test mode override ensures that the DG availability under accident conditions is not compromised as the result of testing. Interlocks to -

the LOCA sensing circuits cause the DG to omaticaUy-reset to ready-to-load operation if a Uni ECCS initiation c L b signal is received during operation in th st mode while synchronized to either Unit 2 or a Unit 3 4 kV emergency bus. Ready-to-load operation is defined as the DG running at rated speed and voltage with the DG output breaker open.

The requirement to automatically energize the emergency loads with offsite power is essentially identical to that of SR 3.8.1.12. The intent in the requirements associated with SR 3.8.1.17.b is to show that the emergency loading is not affected by the DG operation in test mode. In lieu of actual demonstration of connection and loading of loads, testing that adequately shows the capability of the emergency loads to perform these functions is acceptable.

This testing may include any series of sequential, overlapping, or total steps so that the entire connection and loading sequence is verified.

The 24 month Frequency takes into consideration plant conditions required to perform the Surveillance and is intended to be consistent with expected fuel cycle length.

(continued)

PBAPS UNIT 2 B 3.8-31 Revision 0

AC Sources-Operating B 3.8.1 BASES SURVEILLANCE SR 3.8.1.17 (continued) i REQUIREMENTS To minimize testing of the DGs, the Note allows a single test (instead of two tests, one for each unit) to satisfy the requirements for both units. This is allowed since the main purpose of the Surveillance can be met by performing the test on either unit. If the DG fails one of these Surveillances, the DG should be considered inoperable on both units, unless the cause of the failure can be directly related to only one unit.

l SR 3.8.1.18 under accident and loss of offsite power conditions, loads are sequentially connected to the bus by individual load timers. The sequencing logic controls the permissive and starting signals to motor breakers to prevent overloading of the DGs due to high motor starting currents. The 10% load t

sequence time interval tolerance ensures that sufficient time exists for the DG to restore frequency and voltry prior to applying the next load and that safety analysis assumptions regarding ESF equipment time delays are not violated. Reference 11 provides a summary of the automatic loading of emergency buses.

The Frequency of 24 months takes into consideration plant conditions required to perform the Surveillance, and is intended to be consistent with expected fuel cycle lengths.

This SR is modified by a Note. The reason for the Note is that performing the Surveillance would remove a required offsite circuit from service, perturb the electrical distribution system, and challenge safety systems. This Sur ijlance tests the applicable logic associated wi g, u 3 . ' Tint 2) The comparable test specified in the Unit y Tech aLSpecificati s tests the applicable logi LU 3

g p& Woci_ated erformed withinwith Consequently, a test must be Unit 3 Frequency for each unit. As the specified the Surveillance represents separate tests, the Note specifying the restriction for not performing the test while the unit is in MODE 1, 2, or 3 does not h applicability to Uniti3) The Note only applies to Uni th ,the Uni 2 Yurveillances shall not be performed with nit . 2 /in MODE 1, j p y 2- 2, or 3. Credit may be taken for unplann ed eve ts that satisfy this SR. 3 g (O

v

/ "' Nontinuedl PBAPS UNIT 2 B 3.8-32 Revision 0 l

l AC Sources-Operating l B 3.8.1 BASES SURVEILLANCE SR 3.8.1.19 ,

REQUIREMENTS {

(continued) In the event of a DBA coincident with a loss of offsite '

power, the DGs are required to supply the necessary power to ESF systems so that the fuel, RCS, and containment design limits are not exceeded.

This Surveillance demonstrates DG operation, as discussed in the Bases for SR 3.8.1.11, during a loss of offsite power actuation test signal in conjunction with an ECCS initiation signal. In lieu of actual demonstration of connection and loading of loads, testing that adequately shows the capability of the DG system to perform these functions is acceptable. This testing may include any series of .

sequential, overlapping, or total steps so that the entire !

connection and loading sequence is verified.

The Frequency of 24 months takes into consideration plant conditions required to perform the Surveillance and is intended to be consistent with an expected fuel cycle length of 24 months.

l This SR is modified by two Notes. The reason for Note 1 fs !

l to minimize wear and tear on the DGs during testing. For )

the purpose of this testing, the DGs must be started from standby conditions, that is, with the engine coolant and oil being continuously circulated and temperature maintained consistent with manufacturer recommendations. The reason for Note 2 is that performing the Surveillance would remove a required offsite circuit from service, perturb the electrical distribution system, and challenge safety systems.~ ThisSurveJ1 .

( 3 '8soWateDHFUnVJ)]anceThe tests the applicable comparable logic in test specified l fx the Unit [3JTechnical Speci aft 9ns tests the appli_cattd Y j g l oijfc associated with Uni c2 Consequently, a test must be L Lt3 performed within the speci ' frequency for each unit. As the Surveillance represents separate tests, the Note specifying the restriction for not performing the test while

? the uni is in MODE 1, 2, or 3 does not haye applicability

'JQ tflin 3, The Note only applies to UnitC2,) thut the Uni 2 x3 Surveil ances shall not be performed with Unit (2)in MODE 1, 2, or 3. Credit may be taken for unplanned evepts that 4 3 satisfy this SR.

u 3 (continued) l PBApS UNIT 2 B 3.8-33 Revision 0

AC Sources-Operating B 3.8.1 BASES i

SURVEILLANCE SR 3.8.1.20 REQUIREMENTS (continued) This Surveillance demonstrates that the DG starting ,

independence has not been compromised. Also, this Surveillance demonstrates that each engine can achieve i proper speed within the specified time when the DGs are started simultaneously.

The 10 year Frequency is consistent with the recommendations '

of Regulatory Guide 1.108 (Ref. 8). This SR is modified by '

two Notes. The reason for Note 1 is to minimize wear on the DG during testing. For the purpose of this testing, the DGs must be started from standby conditions, that is, with the engine coolant and oil continuously circulated and temperature maintained consistent with manufacturer recommendations. To minimize testing of the DGs, Note 2 allows a single test (instead of two tests, one for each unit) to satisfy the requirements for both units. This is allowed since the main purpose of the Surveillance can be met by performing the test on either unit. If a DG fails one of these Surveillances, a DG should be considered inoperable on both units, unless the cause of the failure can be directly related to only one unit.

SR 3.8.1.21 & La 3 With the exception of this Surveillance, all other Surveillances of this Specification (SR 3,8 4.1 through SR 3.8.1.20) are applied only to the Unit ( 2 C sources.

This Surveillance is provided to d t th the_approp i te '

Surveillanc.es_for_theaequired n'i sources are Iu d ~ governed ~5y the applicable Uni 3 nical Specifications. 5 Performance the applicable Un SurveTllances TtTlT J2 n - siti ~UnT requirements, as wel as satisfying this

- cf Un Sury lance Requirement. Six exceptions are noted G cc,4 4 SR 3.8.1.8 is excepte 3

Uni 3 34)Rs ontr0[efti offsiteofcircuit LC0is3.8.1.

required by the Uni ,

,) Sp 7ec fication, since there is not a second circuit to transfer tr. SR 3.8.1.12, SR 3.8.1.13, SR 3.8.1.17, 4d3 J SR 3.8.1.18 (ECCS load block requirements only), and ~

SR 3.8.1.19 are excepted since these SRs test the Unit 3 s ECCS initiation signal, which i not needed for the AC sources to be OPERABLE on Unit 2

- ' 3 (continued)

PBAPS UNIT 2 B 3.8-34 Revision 0

f l

AC Sources-Operating B 3.8.1 BASES SURVEILLANCE SR 3.8.1.21 (continued) cQ C L;t 3 REQUIREMENTS The frequency required by the applicabl Uni 3 SR also governs performanc that SR for Uni 2

4. Ut3 C UT As Noted, if Uni in MODE 4 or 5, or moving irradiated

' g fuel semblies i -

Unit (3/SR 3.8.2.1 isthe a secondary ble. Thiscontainment, ensures that athe Uni Note to h2

.[.,

u3 h SR w % t require a )SR to be performed, when the & L.A3 Technical Specifica ons exempts ormance of a n1t SR (However, as stated in the Uni SR 3.8.2.1 Note, while performance of an SR is exempted, t SR still must be

,Ch c, u t 3 v

REFERENCES 1. UFSAR, Sections 1.5 and 8.4.2.

2. UFSAR, Sections 8.3 and 8.4.

3. Regulatory Guide 1.9, July 1993.

4. UFSAR, Chapter 14.

5. Generic Letter 84-15.

6. Regulatory Guide 1.93, December 1974.

7. UFSAR, Section 1.5.1.

8. Regulatory Guide 1.108, August 1977.

9. Regulatory Guide 1.137, October 1979.

10. UFSAR, Section 8.5.

PBAPS UNIT 2 B 3.8-35 Revision 0

T AC Sources-Shutdown B 3.8.2 BASES APPLICABLE certain testing and maintenance activities must be SAFETY ANALYSES conducted, provided an acceptable level of risk is not (continued) exceeded. During MODES 4 and 5, performance of a significant number of required testing and maintenance activities is also required. In MODES 4 and 5, the activities are generally planned and administratively controlled. Relaxations from typical MODES 1, 2, and 3 LCO requirements are acceptable during shutdown MODES, based on:

a. The fact that time in an outage is limited. This is a risk prudent goal as well as a utility economic consideration.

b. Requiring appropriate compensatory measures for certain conditions. These may include administrative controls, reliance on systems that do not necessarily meet typical design requirements applied to systems credited in operation MODE analyses, or both,

c. Prudent utility consideration of the risk associated with multiple activities that could affect multiple systems.

d. Maintaining, to the extent practical, the ability to perform required functions (even if not meeting MODES 1, 2, and 3 OPERABILITY requirements) with systems assumed to function during an event.

In the event of an accident during shutdown, this LC0 ensures the capability of supporting systems necessary for avoiding immediate difficulty, assuming either a loss of all offsite power or a loss of all onsite (diesel generator (DG)) power.

The AC sources satisfy Criterion 3 of the NRC Policy Statement.

0 L u. + 3 LCO One offsite circuit supplying the Unit C)onsite Class 1E power distribution subsystem (s) of LC0 3.8.8, "Distrib * .3' Systems-Shutdown," ensures that all required Unit (2Jpowere (.,

loads are powered from offsite power. Two OPERABLE DGs, M3 associated with the Unit (

distributionsubsystem(s)ConsiteClassIEpower i required OPERABLE by LC0 3.8.8, ensures that a diverse power source is available for providing electrical powei support assuming a loss of the EW3 (continued)

PBAPS UNIT 2 B 3.8-37 Revision 0

4_ , Lt 3 .

p L.a (S S L, c,,J.1 b E;s py AC Sources-Shutdown g h B 3.8.2 I

wAbw qW~

BASES

~

\

4 Lo fD \

t 4 L:t 3 LC0 offsite circuit. n addition, s e equ at may be (continued) required by Unit is powered fro Unit sources

Standby _GasTreament(SGT) System). T erefore, &(e.g., g k*

f~ qualified circui@etween the offsite transmission network

&M and_the_ Unit (bonsite Class IE AC electrical power distribution subsystemls), andA3 D@not necessarily 3

g 7 eerELT 3.8.2.b b) "&

1,a[dliferent DEthan those being usedrequirementsi ne o he ga capa

.a required UnitGJsubsystems of each of the requ red 5' # #

'omponents 5st also be OPERABLE. Together, OPERABILITY of 3

- the required offsite circuit (s) and required DG(s) ensures (2- the availability of sufficient AC sources to operate the fM"4 ,, O 3 plant in a safe manner and to mitigate the consequences of A%p6- postulated events during shutdown (e.g., fuel handling

' 'D.u, (p accidents and reactor vessel draindown).

4S-69 L u The qualified UnitG)offsWe circuit must be capable of

'p*'

maintaining rated frepency and voltage while connected to the respective UnitL7.14 kV emergency bus (es), and of accepting required loads during an accident. Qualified offsite circuits are those that are described in the UFSAR and are part of the licensing basis for the unit. A Uni f5 offsite circuit consists of the incoming breaker and disconnect to the startup and emergency auxiliary 40 transformer, the respective circuit path to the emergen auxiliary transformer, and the circuit path to the Unit

-) 4 kV_ emergency _byses_ rec uired by LC0 3.8.8, including f er bFeakers_to_the equirecTnHQ)4 kV emergency buses. A

-(M'iiualifiedUni ffsite circult's requirements are the same 4, L r q as the U Dit circuit's requirements, except that the 3 O circuit pat @, hincluding the feeder breakers, is to the Un 4 kV emergency buses required to be OPERABLE by C0 .8.

The required DGs mu capable of starting, accelerating to rated speed a 1tage, and connecting to their respective Unit emergency bus on detection of bus undervoltage. T is sequence must be accomplished within 10 seconds. Each DG must also be capable of accepting required loads within the assumed loading sequence intervals, and must continue to operate until offsite power can be restored to the 4 h emergency buses. These ,

capabilities are required to be met from a variety of 1 initial conditions such as DG in standby with engine hot and 1 DG in standby with engine at ambient conditions. Additional l (continued)

(<

PBAPS UNIT 2 B 3.8-38 Revision 0

AC Sources-Shutdown '

B 3.8.2 b BASES LC0 DG capabilities must be demonstrated to meet required (continued) Surveillances, e.g., capability of the DG to revert to ,

standby status on a ECCS signal while operating in parallel test mode. Proper sequencing of loads is a required function for DG OPERABILITY. The necessary portions of the !

Emergency Service Water System are also required to provide appropriate cooling to each required DG. !

(9 f., L.it rements for s

the DG capable of supplying The OPERABILITY re ,

power to the Unit powered equipment are the same as described above, except that the required DG must be capable of connecting to its respective Unit (f)4 kV emergency bus. ;

(In addition, the Unit ECCS initiafion logic SRs are not applicable, as describ SR 3.8.2. 2 Bases.)

4. kka -(D ,

It is acceptable for 4 emergency bttfes to be cross tied during shutdown conditions, permitting a single offsite '

power circuit to supply all required buses. No automatic transfer capability is required for offsite circuits to be considered OPERABLE.

APPLICABILITY The AC sources are required to be OPERABLE in MODES 4 and 5 and during movement of irradiated fuel assemblies in the i secondary containment to provide assurance that:

a. Systems providing adequate coolant inventory makeup are available for the irradiated fuel assemblies in the core in case of an inadvertent draindown of the reactor vessel;

b. Systems needed to mitigate a fuel handling accident are available;

c. Systems necessary to mitigate the effects of events that can lead to core damage during shutdown are available; and

d. Instrumentation and control capability is available for monitoring and maintaining the unit in a cold shutdown condition or refueling condition.

AC power requirements for MODES 1, 2, and 3 are covered in LCO 3.8.1.

(continued)

PBAPS UNIT 2 B 3.8-39 Revision 0 i

AC Sources-Shutdown B 3.8.2 BASES ACTIONS A.2.1. A.2.2. A.2.3. A.2.4. B.2.1. B.2.2. B.2.3. B.2.4. C A C.2. C.3. and C.4 (continued) sufficiently conservative actions is made. With two or more required DGs inoperable, the minimum required diversity of AC power sources may not be available. It is, therefore, required to suspend CORE ALTERATIONS, movement of irradiated fuel assemblies in the secondary containment, and activities that could result in inadvertent draining of the reactor vessel.

Suspension of these activities shall not preclude completion of actions to establish a safe conservative condition.

These actions minimize the probability of the occurrence of postulated events. It is further required to immediately initiate action to restore the required AC sources and to continue this action until restoration is accomplished in order to provide the necessary AC power to the plant safety systems.

The Completion Time of immediately is consistent with the required times for actions requiring prompt attention. The restoration of the required AC electrical power sources should be completed as quickly as possible in order to minimize the time during which the plant safety systems may be without sufficient power.

Pursuant to LC0 3.0.6, the Distribution System ACTIONS would not be entered even if all AC sources to it are inoperable, resulting in de-energization. Therefore, the Required Actions of Condition A have been modified by a Note to indicate that when Condition A is entered with no AC power to any required 4 kV emergency bus, ACTIONS for LC0 3.8.8 must be immediately entered. This Note allows Condition A to provide requirements for the loss of the offsite circuit whether or not a required bus is de-energized. LC0 3.8.8 provides the appropriate restrictions for the situation involving a de-energized bus.

SURVEILLANCE SR 3.8.2.1 REQUIREMENTS SR 3.8.2.1 requires the SRs from LC0 3.8.1 that ar

' 4

~

g necessary for ensuring the OPERABILITY of the Uni 2 sources in other than MODES 1, 2, and 3. SR 3.8.1. is not required to be met since only one offsite circuit is required to be OPERABLE. SR 3.8.1.17 is not required to be (continue 41 PBAPS UNIT 2 B 3.8-41 Revision 0

i AC Sources-Shutdown l B 3.8.2 l BASES SURVEILLANCE SR 3.8.2.1 (continued) t REQUIREMENTS met because the required OPERABLE DG(s) is not required to undergo periods of being synchronized to the offsite circuit. SR 3.8.1.20 is excepted because starting independence is not required with the DG(s) that is not required to be OPERABLE. Refer to the corresponding Bases for LCO 3.8.1 for a discussion of each SR.

This SR is modified by a Note. The reason for the Note is to preclude requiring the OPERABLE DG(s) from being paralleled with the offsite power network or otherwise rendered inoperable during the performance of SRs, and to preclude de-energizing a required 4 kV emergency bus or disconnecting a required offsite circuit during performance of SRs. With limited AC sources available, a single event could compromise both the required circuit and the DG. It is the intent that these SRs L.ust still be capable of being met, but actual performance is not required during periods when the DG and offsite circuit are required to be OPERABLE.

SR 3.8.2.2 ; f g

t. 2 3 3

~(

This Surveillance is y ided to di at the appropriate Surveillances for th equired Uni C sources are governed by the Un1 3 ) Technical S fications.

Performance o the ap icable Uni 3 Surveillances will C sit iy Unit 3 requirements, as wel as satisfying this O Uni >Surv ' lance Requirement. Seven exceptions are noted g, u - to _ Unit (ASBs of LC0 3.8.1. SR 3.8.1.8 is excepte e W

ohl_y one1n1tU3 offsite circuit is required by the Uni Specification, since there is not a second circuit to transfer to. SR 3.8.1.12, SR 3.8.1.13, SR 3.8.1.17, I" #

SR 3.8.1.18 (ECCS load block requirements only), and /

SR 3.8.1.19 are excepted since these SRs test the Unit 3

ECCS initiation signal, which sources to be OPERABLE on Uni 2)notneededfortheAC SR 3.8.1.20 is excepted since starting independence is o required with the DG(s) that is not required to be OPERABL b 4. f' 4 The Fregt.ancy required by the applicabl ni 3 SR also governs performance of that SR for Uni 2 (continued) e Lt 3 l l

PBAPS UNIT 2 B 3.8-42 Revision 0

AC Sources-Shutdown B 3.8.2 i

BASES SURVEILLANCE SR 3.8.2.2 (continu i., k+ l 3

REQUIREMENTS

,9 . sJAed, if Unit is not i MODE 1, 2, or 3, the Note to (f> UnitU3, SR 3.8.2.1 s appi le. This ensures that a Unit 2 SR w not require a Uni SR to be performed, when the fug 3 d' ' ',3 '

i U 3' Technical Speci 4qa ons exempts performance of a Unit SR o when Unit 3)is defueled. (However, as stated in the Unit JSR3.8.2. Note, while performance of an SR is exempted, t SR still must be met).

REFERENCES None. 4 F l

i i

l i

l PBAPS UNIT 2 B 3.8-43 Revision 0 l

1

i DC Sources-Operating B 3.8.4 B 3.8 ELECTRICAL POWER SYSTEMS B 3.8.4 DC Sources-Operating BASES BACKGROUND The DC electrical power system provides the AC emergency power system with control power. It also provides a source l of reliable, uninterruptible 125/250 VDC power and 125 VDC control power and instrument power to Class IE and non-Class 1E loads during normal operation and for safe shutdown of the plant following any plant design basis event or accident as documented in the UFSAR 'Ref.1), independent of AC power availability. The DC Electrical Power System meets the intent of the Proposed IEEE Criteria for Class IE Electrical Systems for Nuclear Power Generating Stations (Ref. 2). The DC electrical power system is designed to have sufficient independence, redundancy, and testability to perform its safety functions, assuming a single failure.

The DC power sources provide both motive and control power, and instrument power, to selected safety related equipment, as well as to the nonsafety related equipment. There are two independent divisions per unit, designated Division I and Division II. Each division consists of two 125 VDC batteries. The two 125 VDC batteries in each division are connected in series. Each 125 VDC battery has two chargers (one normally inservice charger and one spare charger) that are exclusively associated with that battery and cannot be interconnected with any other 125 VDC battery. The chargers are supplied from separate 480 V motor control centers (MCCs). Each of these MCCs is connected to an independent emergency AC bus Some of the chargers are capable of being i supplied hy_Uattf3 iCCs, which receive power from a 4 kV

[ h emergenc_y bus, vn) manual transfer switches. However, for a required battery charger to be considered OPERABLE when the M3 unit is in MODE 1, 2, or 3, it must receive power from its associated _ Unit PfiCC. The safety related loads between the riT~I25/250 VDC sub(system are not transferable except for the ,

W Automatic Depressurization System (ADS) valves and logic )

4 LA' circuits and the main steam safety / relief valves. The ADS '

logic circuits and valves and the main steam safety / relief )

valves are normally fed from the Division I DC system.

(continued)

PBAPS UNIT 2 B 3.8-54 Revision 0 l

DC Sources--Operating B 3.8.4 BASES ,

BACKGROUND bank fully charged. Each battery charger has sufficient (continued) capacity to restore the battery from the design minimum charge to its fully charged state within 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months while supplying normal steady state loads following a LOCA coincident with a loss of o ite power.

463 '

A description of th Unit power sources is provided in the Bases for Uni LC0 3 8.4, "DC Sources--Operating."

R) -c, L_a 3 v

APPLICABLE The initial conditions of Design Basis Accident (DBA) and SAFETY ANALYSES transient analyses in the UFSAR, Chapter 14 (Ref.1), assume that Engineered Safety Feature (ESF) systems are OPERABLE.

The DC electrical power system provides normal and emergency DC electrical power for the DGs, emergency auxiliaries, and control and switching during all MODES of operation. The OPERABILITY of the DC subsystems is consistent with the initial assumptions of the accident analyses and is based upon meeting the design basis of the unit. This includes maintaining DC sources OPERABLE during accident conditions in the event of:

a. An assumed loss of all offsite AC power or all onsite AC power; and

b. A worst case single failure.

The DC sources satisfy Criterion 3 of the NRC Policy Statement. '

e

& La 3 LC0 The Uni vision I and Division II DC electrical power subsystems, with each DC subsystem consisting of two 125 V station batteries in series, two battery chargers (one per battery), and the corresponding control equipment and interconnecting cabling supplying power to the associated bus, are required to be OPERABLE to ensure the availability of the required power to shut down the reactor and maintain it in a safe condition after an abnormal operational transient or a postulated DBA. In addition, DC control power (which provides control power for the 4 kV load circuit breakers and the feeder breakers to the 4 kV emergency bus) for two of the four 4 kV emergency buses, as well as control powe or two of the diesel generators, is ,

provided by the Unit 3 MC electrical power subsystems.

Therefore, Unit (j)Div sion I and Division II DC electrical i power subrystems ares, required to be OPERABLE. A Unit t

ua (continued) m s PBAPS UNIT 2 B 3.8-56 Revision 0

l l

DC Sources-Operating l C L_.t 3 6M 3 BASES LC0 DC electrical po r subsystem OPE BI requirements are (continued) the same as the required for ni 2 DC electrical power subsystem, exce t that the Uni 1 Division I DC electrical po subsystem is a owed to consist of only the 125 V batter C an associated battery charger, and the corresponding control equipment and interconnecting cabling supplying 125 V power to the as!.ociated bus; and 2)

Division II DC etlecttical )ower s ystem is allowed to

.c; y 3 ;'sJ coniTit of o~nly the 125Tiilter J an associated battery charger, and the corresponding con rol equipment and interconnecting cabling supplying 125 V power to the associated bus. This exception is allowed only if all 250 VDC loads ar emoved from the associated bus. In

\[ a dTE on, a Uii battery charger can be powered from a Unit 2 AC source, pp described in the Background section of bF S the ases for UnitU3 LC0 3.8.4, "DC Sources-Operating"),

and be considered 0 )ERABLE for the purposes of meeting this LCO. Thus, loss of. any DC electrical power subsystem does notpreventtheminiimumsafetyfunctionfrombeing performed. t gg v

APPLICABILITY The DC electrical power sources are required to be OPERABLE in MODES 1, 2, and 3 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 abnormal operational transients; and

b. Adequate core cooling is provided, and containment integrity and other vital functions are maintained in the event of a postulated DBA.

The DC electrical power requirements for MODES 4 and 5 are addressed in LC0 3.8.5, "DC Sources- Shutdown."

ACTIONS M Pursuant to LC0 3.0.6, the Distribution Systems-Operating ACTIONS would not be entered even if the DC electrical power ,

subsystem inoperability resulted in de-energization of an AC or DC bus. Therefore, the Required Actions of Condition A are modified by a Note to indicate that when Condition A (continued)

PBAPS UNIT 2 B 3.8-57 Revision 0 i

i DC Sources-Operating )

B 3.8.4 i l

BASES 4u 3

ACTIONS M (conti ued "O

, g ) 4 L-a t resul in (f-energization,of a Unit 4 kV emergency bus or a Uni DC bus, Actions for LC0 3.8. must be immediately entere . ThisallowsCfditionAtoproviderequirements for the loss of a Uni 3'DC electrical power subsystem (due to performance of SR 3. 4.7 or SR 3.8.4.8) without regard to whether a bus is de-energized. LC0 3.8.7 provides the appropriate r triction for a de-energized bus.

62) 4.G~t1 If one Unit 3. C electrical power subsystem is inoperable due to performance of SR 3.8.4.7 or SR 3.8.4.8, the remaining DC electrical power subsystems have the capacit to support a safe shutdown and to mitigate an ident 4. La condition. In the case of an inoperable Uni 3 DC 3 electrical pcwer subsystem, since a subsequen postulated worst case singb failure could result in the loss of safety function, continued power operation should not exceed -

7 days. The 7 day Completion Time is based upon the Uni 3d DC electrical power subsystem being inoperable due to performance of SR 3.8.4.7 or SR 3.8.4.8. Performance dM these two SRs will result in inoperability of the Uni 3D 3 divi nal batteries since these batteries are needed or 3 DiiT operation, more time is provided to restore the -

batt ies, if the batteries are inoperable for performance 4ua3 of required Surveillances, to preclude the need for a unit shutdown to perform these Surveillances. The Uni U electrical power subsystems also d at provide power t the 3 same type of equipment as the Uni DC sources. The Completion Time also takes into ac unt the capacity and capability of the remaining DC sources.

4 ut3 Pursuant to LC0 3.0.6, the Distribution Systems-Operating ACTIONS would not be entered even if the DC electrical power subsystem inoperability resulted in de-energization of an AC bus. Therefore, the Required Actions of Condition A are modified by a Note to indicat. that when Condition A results l in de-energization of a Uni kV emergency bus, Actions i for LCO 3.8.7 must be immedi ly entered. This allows Condition A to provide requirements for the loss of a Uni DC electrical power subsystem without regard to whether a l bus is de-energized. LC0 3.8 .7 provides the appropriate 4 W3 i restriction for a de-energizel bus. !

D (continued)

PBAPS UNIT 2 B 3.8-58 Revision 0

DC S urcas-Operating B 3.8.4 BASES l

ACTIONS M (continued) c7 4 Q 3 If one of the Uni 3 DC electrical power subsystems is :

inoperable for reasons other than Condition A, the remaining DC electrical power subsystems have the cap;;ity to support a safe shutdown and to mitigate an accident condition.

Since a subsequent worst case single failure could, however, result in a loss of minimum necessary DC electrical >

subsystems to mitigate a worst case accident, continued power operation should not exceed 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . The 12 hour1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months Completion Time reflects a reasonable time to assess unit status as a function of the inoperable DC electrical power subsy tem and takes into_ consideration the importance of the Uni 3 C electrical power subsystem.

0 & J3 M 3 g La 3 Condition C represents one Uni 2 division with a loss of ability to completely respond to an event, and a potential loss of ability to remain energized during normal operation.

It is therefore imperative that the operator's attention -

focus on stabilizing the unit, minimizing the potential for complete loss of DC p wer.

4 L i- 3 !

If one of the Uni C electrical power subsystems is .

inoperable (e.g., noperable battery / batteries, inoperable required battery charger / chargers, or inoperable required.

battery charger / chargers and associated battery / batteries),

the remaining DC electrical power subsystems have the capacity to support a safe shutdown and to mitigate an accident condition. Since a subsequent worst case single failure could result in the loss of minimum necessary DC electrical subsystems to mitigate a worst case accident, continued power operation should not exceed 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months . The 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Completion Time is consistent with Regulatory Guide 1.93 (Ref. 4) and reflects a reasonable time to assess unit status as a function of th noperable DC electrical power division and, if the Uni DC electrical power ;

division is not restored to OPE LE status, to prepare to '

initiate an orderly and safe uni shutdown. The 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months limit is also consistent with tr,e allowed time for an t inoperable Uni DC Distributi'n System division.

b' v

3 (continued) i PBAPS UNIT 2 B 3.8-59 Revision 0

P

I DC Sources-Operating i B 3.8.4 l l

BASES )

ACTIONS D.1 and (LZ i (continued)

If the DC electrical power subsystem cannot be restored to OPERABLE status within the required Completion Time, the unit must be brought to a MODE in which the LC0 does not apply. To achieve this status, the unit must be brought to at least MODE 3 within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and to MODE 4 within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months . The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems. The Completion Time to bring the unit to MODE 4 is consistent with the time l specified in Regulatory Guide 1.93 (Ref. 4).

L1 .

1 Condition E corresponds to a level of degradation in the DC electrical power subsystems that causes a required safety function to be lost. When more than one DC source is lost, this results in a loss of a required function, thus the plant is in a condition outside the accident analysis.

Therefore, no additional time is justified for continued operation. LC0 3.0.3 must be entered immediately to commence a controlled shutdown.

~

A ( ) f L _:+ 3 1 SURVEILLANCE As Noted at the beginning of the SRs, SR 3 r4. M hrough l REQUIREMENTS SR 3.8.4.8 are applicable only to the Uni 2 DC electrical power subsystems and SR 3.8.4.9 is applica e only to the Uni 3,DC electrical power subsystems. ;

(O C Ut 3 SR 3T8.4.1 Verifying battery terminal voltage while on float charge for !

the batteries helps to ensure the effectiveness of the l charging system and tha ability of the batteries to perform !

their intended function. Float charge is the condition in l which the charger is supplying the continuous charge required to overcome the internal losses of a battery (or battery cell) and maintain the battery (or a battery cell) in a fully charged state. The voltage requirements are (continued)

PBAPS UNIT 2 8 3.8-60 Revision 0 i

DC Sources-Operating B 3.8.4 BASES SURVEILLANO. SR 3.8.4.8 (continued)

REQUIREMENTS satisfy the Surveillance. The DC batteries of the other unit are exempted from this restriction since they are required to be OPERABLE by both units and the Surveillance cannot be performed in the manner required by the Note without resulting in a dual unit shutdown.

1 SR 3.8.4.9 With the exception of this Surveillance, all,ather Surveillances of this Specification (SR (4.1 through SR 3.8.4.8) are applied only to the Uni DC electrical power subsystems. This Surveillance is p vided to direct that the. appropriate Surveillances for the required UnitC3) '

[d2 Je.chnical Specifications.DC

\ elect icalAfpower Performance subsystems are governed the applicable -

"' Unit

" , , well(3)Sur as satufying <eillances will sat _isfy UnitQ) this Unitb21Survet11/ ncerequirements, Req ement. as 4; ws 3 Q). 3 & .L d5 The Frequency required by the ppl cab Uni SR also gover performance of that SR for Unit 2f A Noted, if Unit ( is in MODE 4 or 5, or moving irradiated fuel ,

assem ies in the secondary containment, the Note to Unit ~

,(; u SR 3.8.5.1 is applicable This ensures that a Unit 2 SR 'M h will trequireaUnit(s3 SR to be performed, when (th)e 3 Technical SpecifiJ:)ations exempts performance of a f f k uni (However, as. stated in the Unit (3]SR 3.8.5.1 b/ UNote, while SR.

performance ' f the SR is exemptecl, the SR still o must be met.) 4 v

REFERENCES 1. UFSAR, Chapter 14.

2. " Proposed IEEE Criteria for Class 1E Electrical Systems for Nuclear Power Generating Stations," June 1969.

3. IEEE Standard 485, 1983.

4. Regulatory Guide 1.93, December 1974.

5. IEEE Standard 450, 1987, i

I PBAPS UNIT 2 B 3.8-66 Revisiu 0

DC Sources-Shutdown B 3.8.5 B 3.8 ELECTRICAL POWER SYSTEMS B 3.8.5 DC Sources-Shutdown !

BASES BACKGROUND A description of the DC sources is protided in the Bases for LCO 3.8.4, "DC Sources-Operating."

APPLICABLE- The initial conditions of Desig's Basis Accident and SAFETY ANALYSES transient analyses in the UFSAR, Chapter 14 (Ref.1), assume that Engineered Safety Feature systems are OPERABLE. The DC electrical power system provides normal and emergency DC electrical power for the diesel generators (DGs), emergency auxiliaries, and control and switching during all MODES of operation.

The OPERABILI'Y of the DC subsystems is consistent with the initial assumptions of the accident analyses and the requirements for the supported systems' OPERABILITY.

The OPERABILIT) of the minimum DC electrical power sources during MODES 4 'and 5 and during movement of irradiated fuel ,

assemblies in secondary containment ensures that:

a. The facility can be maintained in the shutdown or refueling condition for extended periods;

b. Sufficient instrumentation and control capability is- i available for monitoring and maintaining the unit status; and I

c. Adequate DC electrical power is provided to mitigate events postulated during shutdown, such as an .

inadvertent draindown of the vessel or a fuel handling l accident.

The DC sources satisfy Criterion 3 of the NRC Policy i Statement.

LC0 The Unit 2tDC (electrical O ) 6powerL_asubsystems, 3 with each DC subsystem consisting of two 125 V station batteries in series, two battery chargers (one per battery), and the corresponding control equipment and interconnect',g cabling I supplying power to the associated bus, are required to be (continued)

PBAPS UNIT 2 B 3.8-67 Revision 0 i

DC Sources-Shutdown B 3.8.5 BASES gg y

LC0 2)DCdistributionsubsystems-(continued) OPERABLE required CPERABLE tobysupport LCO Unit (3.8.8, " Distribution Systems Shutdown." When the equipment required OPERABLE: 1) does not require 250 VDC from the DC electrical power subsystem; and 2) does not require 125 VDC from one of the two 125 batteries of the DC electrical power subsystem, the Unit DC electrical power subsystem requirements can be modifi C5 to only include one 125 V battery (the battery needed to '

provide power to required equipment), an associated battery charger, and the corresponding control equipment and interconnecting cabling supplying 125 V power to the ,

associated bus. This exception is allowed only if all -

250 VDC loads are removed from the associated bus. In addition, DC control power (which provides control power for the 4 kV load circuit breakers and tiie feeder breakers to the 4 kV emergency bus) for two of Llie four 4 kV emergency buses, as well as control power for of the diesel generators, is provided by the Un Celectricalpower,g subsystems. Therefore, the Uni 3 TEtrical power subsystems needed to support requ ritd c.omp.9aents_are also /

T :

required to be OPERABLE. The Unit (J3 DC electrical power O '

c subsyitem_0PIRABILI L requirements are the same as those 3 required for a Viilt 2)DC electrical power subsystem. In i 4 addition, battery c argers (Unit 2 and Unit 3) can be o_: t 3 powered from the opposite unit's AC source (as described in the Background section of the Bases for LC0 3.8.4, "DC Sources-Operating"), and be considered OPERABLE for the ,

purpose of meeting this LCO.

This requirement ensures the availability of sufficient DC electrical power sources to operate the unit in a safe manner and to mitigate the consequences of postulated events during shutdown (e.g., fuel handling accidents and inadvertent reactor vessel draindown).

APPLICABILITY The DC electrical power sources required to be OPERABLE in MODES 4 and 5 and during movement of irradiated fuel assemblies in the secondary containment provide assurance :

that:

a. Required features to provide adequate coolant inventory makeup are available for the irradiated fuel assemblies in the core in case of an inadvertent draindown of the reactor vessel; ,

(continued) '

PBAPS UNIT 2 B 3.8-6B Revision 0 ;

DC Sources-Shutdown B 3.8.5

( llASES ACTIONS A.I. A.2.1. A.2.2. A.2.3, and A.2.4 (continued)

Suspension of these activities shall not preclude completion of actions to establish a safe conservative condition.

These actions minimize the probability of the occurrence of postulated events. It is further required to immediately initiate action to restore the required DC electrical power subsystems and to continue this action until restoration is accomplished in order to provide the necessary DC electrical power to the plant safety systems.

The Completion Time of immediately is consistent with the required times for actions requiring prompt attention. The restoration of the required DC electrical power subsystems should be completed as quickly as possible in order to minimize the time during which the plant safety systems may be without sufficient power.

SURVEILLANCE SR 3.8.5.1 REQUIREMENTS SR 3.8.5.1 requires performance of all Surveillances required by SR 3.8.4.1 through SR 3.8.4.8. Therefore, see the corresponding Bases for LC0 3.8.4 for a discussion of each SR.

This SR is modified by a Note. The reason for the Note is to preclude requiring the OPERABLE DC electrical power subsystems from being discharged below their capability to provide the required power supply or otherwise rendered inoperable during the performance of SRs. It is the intent that these SRs must still be capable of being met, but actual performance is not required.

SR 3.8.5.2 g4g This Surveillance is provided to direc that the appropriate Surveillances for the required Unit ' C electrical power subsystems are governed by the Unit 3 echnical Specifications. Performance of he applicable Unit Cy Surveillances will s sfy Uni 3) requirements,asw 1 as satisfying this Uni 2 urvei1 The Frequency required y he app -}icable Unince 3 R Requiregent.

also governs performance of tha SR for U i D 3 M d

(continued)

U "g h g 3 4.

( L-0 PBAPS UNIT 2 B 3.8-70 Revision 0

DC Sources-Shutdown B 3.8.5 BASES SURVEILLANCE SR 3.8.5.2 (contin ^ ) g 4 Ut3 REQUIREMENTS '3 As Noted, if Uni ) s in MODE 4 5, or moving irradiated fu semblies i the secondary',o ,

"tirii SR 3.8.5.1 is appli T5. containment,theNotetoThis ensures th g y3 SR_ w not require a Unit 3)SR to be performed, when the .u3

'g ni 3) Technical Specifications exempts per ance of a ditt)SR. (However, as stated in the Unit 3 SR 3.8.5.1 Note, while performance of an SR is exempted the SR still must be met.)

REFERENCES 1. UFSAR, Chapter 14.

l l

l PBAPS UNIT 2 B 3.8-71 Revision 0 i

I Distribution Systems-Operating j B 3.8.7 8 3.8 ELECTRICAL POWER SYSTEMS B 3.8.7 Distribution Systems-0perating BASES BACKGROUND The onsite Class 1E AC and DC electrical power distribution system is divided into redundant and independent AC and DC electrical power distribution subsystems. g TheprimaryACdistributionsystemforUnit[2,onsistsof four 4 kV emergency buses each having two offsite sources of power as well as an onsite diesel generator (DG) source.

Each 4 kV emergency bus is connected to its normal source of power via either emergency auxiliary transformer no. 2 or no. 3. During a loss of the normal supply of offsite power to the 4 kV emergency buses, the alternate supply breaker from the alternate supply of offsite power for the 4 kV emergency buses attempts to close. If all offsite sources are unavailable, the onsite emergency DGs supply power to the 4 kV emergency buses. (However, these supply breakers are not governed by this LC0; they are governed by LC0 3.8.1, "AC Sources-0perating".)

3 The secondary plant distrit,utjon system for Uni 2 includes 480 VAC load centers p EQ4,

($ _Eq)4, (3) E334, and E414.-($

6f3 (.'

There are two independelt 125/250 VDC electrical power distribution subsystems for Unit 2 that support the necessary power fo EgFfu tions. g 3 In addition, since tome c . nents required by Unit 2 O L :t 3 l receive power throug ni 3 electrical power distribution i subsystems, the Uni AC and DC electrical power distribution subsyst ms needed to support the required G equipment re also addressed in LC0 3.8.7. A description of 6 LJ 3 Nfthe'Un~TI' AC and DC Electrical Power Distribution System is provided n the Bases for Uni 3 LC0 3.8.7, " Distribution System-Operating ( ".us(.)

r - ~' 4 y4 3 The list of required Unit 2; distribution buses is presented in Table B 3.8.7-1.

(continued) l PBAPS UNIT 2 B 3.8-79 Revision 0

Distribution Systems-Operating B 3.8.7 BASES (continued)

APPLICABLE The initial conditions of Design Basis Accident (DBA) and SAFETY ANALYSES transient analyses in the UFSAR, Chapter 14 (Ref.1), assume Engineered Safety Feature (ESF) systems are OPERABLE. The AC and DC electrical power distribution systems are designed to provide sufficient capacity, capability, redundancy, and reliability to ensure the availability of necessary power to ESF systems so that the fuel, Reactor Coolant System, and containment design limits are not exceeded. These limits are discussed in more detail in the Bases for Section 3.2, Power Distribution Limits; Section 3.5, Emergency Core Cooling Systems (ECCS) and Reactor Core Isolation Cooling (RCIC) System; and Section 3.6 Containment Systems.

The OPERABILITY of the AC and DC electrical power distribution subsystems is consistent with the initial assumptions of the accident analyses and is based upon meeting the design basis of the unit. This includes maintaining distribution systems OPERABLE during accident conditions in the event of:

a. An assumed loss of all offsite power or all onsite AC electrical power; and

b. A postulated worst case single failure.

The AC and DC electrical power distribution system satisfies Criterion 3 of the NRC Policy Statement.

G k.3 3 LC0 The Unit and DC electrical power distribution -

subsystems are required to be OPERABLE. TherequiredUnit@2 electrical power distribution subsystems listed in (,, u Table B 3.8.7-1 ensure the availability of AC and DC s electrical power for the systems required to shut down the reactor and maintain it in a safe condition after an abnormal operational transient or a postulated DBA. As W 3 stated in the Table, each division of the AC and L: 3 Oy3 In b .5 h~ electrical power additiont .ince s somedistribution componentssystems required by isUnit a subsyste 2 receive

[C-6~~\f, powenthr.oug(e.Uriit(3>

subsystems ( g., Standbyelectrical power(SGT)

Gas Treatment distribution Systep, A4- .A gmergency-heat ~s~fhK componentib, and DC control power for two pp1*44 of the four 4 kV emergency buses, as wel f control power ssu -

for two of the diesel generators), t nit 3 AC and DC 4 w\2J3 7 c, m (continued)

L Wi5 g b $N<.Wh s k*, j

% k b.l W Ew"3*y PBAPS UNIT 2 8 3.8-80 @ n0

', s

Distribution Syste:Is-Operating B 3.8.7 BASES LCO electrical power distribution subsystems needed to supp (continued) the required equipment must also be OPERABLE. The Unit electrical power distributio subsystems that may be required are listed nsUnit 3 able B 3.8.7-1. E' M 5 4 Le s G) C L t3 Maintaining the Uni 2DivisionIandIIandrequiredUrdt,q AC and DC electrical power distribution subsystems OPERABL ensures that the redundancy incorporated into the design of ESF is not defeated. Therefore, a single failure within any system or within the electrical power distribution subsystems will not prevent safe shutdown of the reactor.

The Unit 2 and Unit 3 AC electrical power distribution subsystems require the associated buses and electrical circuits to be energized to their proper voltages. The Unit 2 and Unit 3 DC electrical power distribution subsystems require the associated buses to be energized to Cu3 their proper voltage from eithe he associated batteries o e chargers. However, when a Uni DC eTiiictYR1175Wr subsystem is only required to h e one 125 V battery and associated battery charger to be considered OPERABLE (as -

described in the LCO section of the Bases for LC0 3.8.4, "DC Sources-Operating"), the proper voltage to which the associated bus is required to be energized is lowered from 250 V to 125 V (as read from the associated battery charger).

Based on the number of safety significant electrical loads associated with each bus listed in Table B 3.8.7-1, if one or more of the buses becomes inoperable, entry into the appropriate ACTIONS of LC0 3.8.7 is required. Other buses, such as motor control centers (MCC) and distribution panels, which help comprise the AC and DC distribution systems are i not listed in Table B 3.8.7-1. The loss of electrical loads 1 associated with these buses may not result in a complete loss of a redundant safety function necessary to shut down l the reactor and maintain it in a safe condition. Therefore, j should one or more of these buses become inoperable due to a failure not affecting the OPERABILITY of a bus listed in Table B 3.8.7-1 (e.g., a breaker supplying a single MCC i fails open), the individual loads on the bus would be considered inoperable, and the appropriate Conditions and ;

Required Actions of the LCOs governing the individual loads would be entered. If however, one or more of these buses is .

inoperable due to a failure also affecting the OPERABILITY I of a bus listed in Table B 3.8.7-1 (e.g., loss of a 4 kV (continued)

PBAPS UNIT 2 B 3.8-81 Revision 0 ,

I

N Distribution Systems-Operating B 3.8.7 BASES (continued)

- ACTIONS L.1 l Pursuant to LC0 3.0.6, the DC Sources-Operating ACTIONS would not be entered even if the AC electrical power i distribution subsystem inoperability resulted in de- i energization of a required battery charger. Therefore, the j Required Actions of Condition A are modified by a Note to indicate'that w en Condition A results in de-energization of a equired U_ni_t battery charger, Actions for LCO 3.8.4 L must be immedia y entered. This allows Condition A to provide requirements for the loss of a Unit M3 electrical rb. 0"

[W3 )ower distribution subsystem without regardTo whether a aattery charger is de-energized. LCO 3.8.4 provides the 3

appropriate restriction for a de-energ ed battery charger. '

2- /,Lt3 .

If one or more of the required Unit 3 C electrical power distribution subsystems are inoperab e, and a loss of function has not occurred as described in Condition F, the :

remaining AC electrical power distribution subsystems have ,

the capacity to support a safe shutdown and to mitigate an accident condition. Since a subsequent worst case single. ,

failure could, however, result in the loss of certain safety functions, continued power operation should not exceed 7 days. The 7 day Completion Time takes into account the capacity and capability of the remaining AC electrical power distribution subsystems, and is based on the shortest restoration time allowed for the systems affected by the inoperable AC electrical power distribution subsystem in the respective system Specification.

'Z C Cf3 If one of the Unit 3 C electrical power distribution subsystems is inoperable, .the remaining DC electrical power t distribution subsystems have the capacity to support a safe !

shutdown and to mitigate an accident condition. Since a !

subsequent worst case single failure could, however, result in the loss of safety function, continued power operation ,

should not exceed 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . The 12 hour1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months Completion Time t reflects a reasonable time to assess unit status as a function of the inoperable DC electrical power distribution subs s< tem and takes into consideration the importance of the -

Unit C electrical power distribution subsystem. ;

2- .C' LF3 (continued) l j

i C

PBAPS UNIT 2 B 3.8-83 Revision 0 l

M-- - . , . ._w. - -

Distribution Systems-Operating B 3.8.7 BASES w

ACTIONS L1 <3 g u3 (continued)

With one Unit 2 AC electrical power distribution subsystem inoperable, the remaining AC electrical power distribution subsystems are capable of supporting the minimum safety functions necessary to shut down the reactor and maintain it in a safe shutdown condition, assuming no single failure.

The overall reliability is reduced, however, because a single failure in the remaining power distribution subsystems could result in the minimum required ESF 8 E' W functions not being supported. Therefore, the Unit . C electrical power distribution subsystem must be restored to OPERABLE status within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months .

The Condition C worst scenario is one 4 kV emergency bus without AC power (i.e., no offsite power to the 4 kV emergency bus and the associated DG inoperable). In this

/ ~ Condit4on, the unit is more vulnerable to a complete loss of

.[; y 3{,3 U_n g 2,AC power. It is, therefore, imperative that the unit operators' attention be focused on minimizing the potential for loss of power to the remaining buses by stabilizing the unit, and on restoring power to the affected bus (es). The 8 hour9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months time limit before requiring a unit shutdown in this Condition is acceptable because:

a. There is a potential for decreased safety if the unit operators' attention is diverted from the evaluations and actions necessary to restore power to the affected bus (es) to the actions associated with taking the unit to shutdown within this time limit,

b. The potential for an event in conjunction with a single failure of a redundant component in the division with AC power. (The redundant component is verified OPERABLE in accordance with Specification 5.5.11, " Safety Function Determination Program (SFDP).")

The second Completion Time for Required Action C.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 LC0 3.8.7.a If Condition C is entered while, for instance, a UnithC bus is inoperable and subsequently returned OPERAB _E, this LC0 may already have been not met for up to 2 hou rs. This situation could lead

# 3 (continued)

PBAPS UNIT 2 8 3.8-84 Revision 0

Distribution Systems-Operating B 3.8.7 BASES E' #

ACTIONS L1 (continued) to a total duration of 10 hours1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months sinc gitial failure of the LCO, to restore the Unit @2C El ctrital Power .

Distribution System. At this time a Unit (MDC bus could again become inoperable, and Unit C Electrical Power Distribution System could be resto(2)dre 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 results in establishing the " time zero" at the time LCO 3.8.7.a was initially not met, instead of at the time Condition C was entered. The 16 hour1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months Completion Time is an acceptable limitation on this potential to fail to meet the LC0 3.8.7.a indefinitely.

.f, U 3 With one Unit C electrical power distribution subsystem inoperable, t e remaining DC electrical power distribution subsystem is capable of supporting the minimum safety functions necessary to shut down the reactor and maintain it in a safe shutdown condition, assuming no single failure.

The overall reliability is reduced, however, because a single failure in the remaining DC electrical power distribution subsystem could result in the minimum requi ed ESF functions not being supported. Therefore, the Unit ODC electrical power distribution subsystem must be restore to OPERABLE status within 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months .

3 S L:t 3 3 ,, tut 3 Condition D represents one Unit 2 lectrical power distribution subsystem without adequate DC power, potentially with both the battery (s) significantly degraded and the associated charger (s) nonfunctioning. In this situation the plant is sign

, complete loss _of_All_Unitl2)ificantly C power. It more vulnerable to a is, therefore,

~ inperative that the operator's attention focus on 3 stabilizing the plant, minimizing the potential for loss of power to the remaining electrical power distribution

'('*' y $ subsystems, and restoring power to the affected electrical power distribution subsystem.

(continued _).

\.

PBAPS UNIT 2 8 3.8-85 Revision 0

Distribution Systeas-Operating l B 3.8.7 BASES ,

ACTIONS D_d (continued)

This 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months limit is more conservative than Completion Times allowed for the majority of components that would be without power. Taking exception to LC0 3.0.2 for components without adequate DC power, which would have Required Action Completion Times shorter than 2 hours2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months , is acceptable because '

of:

a. The potential for decreased safety when requiring a

, change in plant conditions (i.e., requiring a '

shutdown) while not allowing stable operations to-continue;

b. The potential for decreased safety when requiring _

entry into numerous applicable Conditions and Required Actions for components without DC power, while not p my! ding sufficient time for the operators to perform the necessary evaluations and actions for restoring power to the affected subsystem;

c. The potential for an event in conjunction with a i single failure of a redundant component.

The 2 hour2.314815e-5 days 5.555556e-4 hours 3.306878e-6 weeks 7.61e-7 months Completion Time for DC electrical power i distribution subsystems is consistent with Regulatory Guide 1.93 (Ref. 2).

The second Completion Time for Required Action D.1 establishes a limit on the maximum time allowed for any combination of required electrical power distribution subsystems to be inoperable during any single contiguous occurrence of failing to meet LC0 3.8. .a.

is entered while, for instance, a Uni If_ Contitt@arQ)4, 2 At bus iP gp33 inoperable and subsequently restored 0 BLE, LCO 1.8.h. (4, y may already have been not met for up to 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months . This situation could lead to a total duration of 10 hour1.157407e-4 days 0.00278 hours 1.653439e-5 weeks 3.805e-6 months since/3 initial failure of LCO 3.8.7.a. to restore the Uni C Q Elec cal Power Distribution System. At this ti a h') Unit 2 JAC bus could again become inoperable, and Unit 2 DC Elec cal Power Distribution System could be restored 5 U3 OPERABLE. This could continue indefinitely.

(continued)

PBAPS UNIT 2 B 3.8-86 Revision 0 ,

1

Distribution Systems-0perating B 3.8.7 Table B 3.8.7-1 (page 1 of 1) ]

AC and DC Electrical Power Distribution Systems '

TYPE VOLTAGE DIVISION I* DIVISION II*

l AC buses 4160 V Emerge cy Buses Eme cy Buses E '2 E E42) 3 E12)M4

__Q / gj) S u s 480 V Load Centgrs Loh nurs E24,E3'24 ,E@

j

(

RS)'%* E( @& (Q 4. w G DC buses 250 V Distribution Panel Distribution Panel d'AD18 @BD18 l (S) # 7' fG ) & W 3

Each division of the AC and DC electrical power distribution systems is a subsystem.

I PBAPS UNIT 2 B 3.8-89 Revision 0

Distribution Systems-Operating B 3.8.7 Table B 3.8.7-1 (page 1 of 1)

AC and DC Electrical Power Distribution Systems TYPE VOLTAGE DIVISION I* DIVISION II*

AC buses 4160 V Eme y B ses Emergepcy Buses E E E@, E )

AT (3 3 4Ws 480 V Loa Centgrs low Cen rs E24,E44 Eq4, Ep H@'ji ' (h(S) 4. ut 3 DC buses 250 V Distribution Panel Distribution Panel

(?,AD18 018 (3) # 7'

&R3

Each division of the AC and DC electrical power distribution systems is a subsystem.

l:

i l

F l

PBAPS UNll 2 B 3.8-89 Revision 0 l

Distribution ' Systers-Shutdown -

B 3.8.8

~

BASES (continued)

LCO- Various combinations of subsystems, equipment, and' components are required OPERABLE by other LCOs, depending on the specific plant condition. Implicit in those requirements is the required OPERABILITY of necess M support required features. This LCO explicit equires 4,.

energization of the portions of the Uni e actrical . u;F 3 distribution system necessary to support PERABILITY of.

Technical Specifications required systems, equipment,- and components-both specifically addressed by their own LCO,.

and implicitly required by the definition of OPERABILITY, In addition, some components that may be required by Unit

~

OL receive power through' UnitQ) electrical power distribution f

.f. a subsystems (e.g., Standby Gas Treatment (SGT) System,and DC 3 control power for two of the four 4 kV emergency bys'es, as well as control ower for two of the diesel gener ors).

Therefore, Unit 3 AC and DC electrical power d ribution subsystems neede to support the required e pment must also be OPERABLE. g 3 y ca,t g b L In addition, it is acceptable for requirea puse% s to%,5LA.Sp ne 4

cross-tied during shutdown conditions, permitting a single us.s.

source to supply multiple redundant buses, provided the

_.s source is capable of maintaining proper frequency-(if .

required) and voltage.

Maintaining these portions of the distribution system energized ensures the availability of sufficient power to operate the plant in a safe manner to mitigate the consequences of postulated events during shutdown (e.g.,

fuel handling accidents and inadvertent reactor vessel draindown).

APPLICABILITY The AC and DC electrical power distribution subsystems required to be OPERABLE in MODES 4 and 5 and during movement of irradiated fuel assemblies in the secondary containment 4

j provide assurance that:

e"

a. Systems to provide adequate coolant inventory makeup are available for the irradiated fuel in the core in case of an inadvertent draindown of the reactor vessel;

b. Systems needed to mitigate a fuel handling accident are available;

... (continued) k-..

.PBAP UNIT 2 B 3.8-91 Revision 0

_

ML20085D786

Text

Navigation menu

Search