ML20137V250
| ML20137V250 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 04/15/1997 |
| From: | SOUTHERN CALIFORNIA EDISON CO. |
| To: | |
| Shared Package | |
| ML20137V216 | List: |
| References | |
| NUDOCS 9704170248 | |
| Download: ML20137V250 (31) | |
Text
.
AC Sources-Operating 3
3.8.1 i
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.8.1.7
NOTE--------------------
J All DG starts may be preceded by an engine prelube period.
1 Verify each DG starts from standby 184 days condition and achieves, in s 10 seconds, voltage a 3924 V and s 4796 V, and frequency a 58.8 Hz and s 61.2 Hz.
NOTE------------------
Credit may be taken for unplanned events that satisfy this SR.
Verify automatic and manual transfer of AC 24 months power sources from the normal offsite circuit to each alternate required offsite i
circuit.
(continued) 9704170248 970415 PDR ADOCK 05000361 p
PDR SAN ONOFRE--UNIT 2 3.8-7 Amendment No. 127
. - -.. ~
i AC Sources-Operating l
B 3.8.1 B-3.8. ELECTRICAL. POWER SYSTEMS l
B 3.8.1 AC Sources-Operating L
BASES BACKGROUND-The Class 1E Electrical Power Distribution System AC sources I
~
consist of the _offsite power sources (preferred or normal i
power sources and alternate (s)), and the onsite standby i
power sources (Train A and Train B diesel generators (DGs)).
As required by 10 CFR 50, Appendix A, GDC 17 (Ref.1), the design of the AC electrical power system provides independence and redundancy to ensure an available source of power to the Engineered Safety Feature (ESF) systems.
}
.The onsite Class 1E AC Distribution System is divided into i
redundant load groups.(trains) so that the loss of any one i
group does not prevent the minimum safety functions from being performed.
Each train has connections to two preferred offsite power sources and a single DG.
One source of offsite power (Offsite circuit #1) for each unit is normally provided through Reserve Auxiliary transfonners XR1 and XR2 for the specific unit. XR1 feeds one 4.16 KV ESF bus (Train A) A04 and XR2 feeds the other 4.16 KV ESF bus (Train B) A06 of the onsite Class 1E AC distribution system for each unit. The second source of offsite power (Offsite circuit #2) is provided by the other unit's Reserve Auxiliary Transformers XR1 and XR2 through the train oriented 4.16 KV ESF bus crossties between the two units.
In addition, each class 1E Switchgear can be connected to a third offsite power source via the Unit Auxiliary Transformers by manually removing the link in the isolated phase bus between the Main Generator and the Main transformer of the non-operating Unit and racking-in the 4.16 KV circuit breaker which is normally left racked-out (withdrawn) into the fully equipped cubicle connected to the Lnit Auxiliary transformer of the same Unit.
An offsite circuit includes all breakers, transformers, switches, interrupting devices, cabling, and controls required to transmit power from the offsite transmission network to the onsite Class 1E ESF bus or buses.
Certain required unit loads are returned to service in a predetermined sequence in order to prevent overloading the transformer supplying offsite power to the onsite Class 1E (continued)
. SAN ONOFRE--UNIT 2 B 3.8-1 Amendment No. 127
.. ~
o,
=.
AC Sources-0perating s
B 3.8.1 BASES BACKGROUND Distribution System. Within 77 seconds after the initiating (continued) signal is received, all automatic and permanently connected loads needed to recover the unit or maintain it in a safe condition are returned to service via the programmed time interval loid sequence.
The onsite standby power source for each 4.16 kV ESF bus is a dedicated DG. DGs G002 and G003 are dedicated to ESF buses A04 and A06, respectively. A DG starts automatically on a safety injection actuation signal (SIAS) (i.e., low pressurizer pressure or high containment pressure signals) or on an ESF bus degraded voltage or undervoltage signal.
After the DG has started, it will automatically tie to its respective bus after offsite power is tripped as a consequence of ESF bus undervoltage or degraded voltage, independent of or coincident with an SIAS signal.
The DGs will also start and operate in the standby mode without tying to the ESF bus on an SIAS alone.
Following the trip of offsite power, an undervoltage signal strips nonpermanent loads from the ESF bus. When the DG is tied to the ESF bus, loads are then sequentially connected to its respective ESF bus by the programmed time interval load sequence.
The sequencing logic controls the permissive and starting signals to motor breakers to prevent overloading the DG by automatic load application.
In the event of a loss of preferred power, the ESF electrical loads are automatically connected to the DGs in sufficient time to provide for safe reactor shutdown and to mitigate the consequences of a Design Basis Accident (DBA) such as a loss of coolant accident (LOCA).
Certain required unit loads are returned to service in a predetermined sequence in order to prevent overioading the DG in the process. Within 77 seconds after the initiating signal is received, all loads needed to recover the unit or maintain it in a safe condition are returned to service.
Ratings for Train A and Train B DGs satisfy the requirements of Regulatory Guide 1.9 (Ref. 3). The continuous service rating of each DG is 4700 kW with 10% overload permissible for up to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> in any 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period. However, for standby class of service like the San Onofre DGs the manufacturer allows specific overload values up to 116.1% of continuous duty rating based on the total hours the DG is (continued)
SAN ON0FRE--UNIT 2 B 3.8-2 Amendment No. 127
AC Sources-Operating g
B 3.8.1 BASES BACKGROUND operated per year. The ESF loads that are powered from the (continued) 4.16 kV ESF buses are listed in Reference 2, APPLICABLE The initial conditions of DBA and transient analyses in the SAFETY ANALYSES UFSAR, Chapter 6 (Ref. 4) and Chapter 15 (Ref. 5), 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 3.4, Reactor Coolant System (RCS); 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 tiie l
unit. This results in maintaining at least one train of 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 j
b.
A worst case single failure.
The AC sources satisfy Criterion 3 of NRC Policy Statement.
LCO Two qualified circuits between the offsite transmission network and the onsite Class 1E Electrical Power Distribution System and separate and independent DGs for each train ensure availability of the required power to shut down the reactor and maintain it in a safe shutdown condition after an anticipated operational occurrence (A00) or a postulated DBA.
Qualified offsite circuits are those that are described in the UFSAR and are part of the licensing basis for the unit.
(continued)
SAN ON0FRE--UNIT 2 B 3.8-3 Amendment No. 127
l AC Sources-Operating B 3.8.1 s
BASES l
LC0 Each offsite circuit must be capable of maintaining rated (continued) frequency and voltage, and accepting required loads during an accident, while connected to the ESF buses.
One source of offsite. power (Offsite circuit #1) for each
'I unit is normally provided through Reserve Auxiliary 1
Transformers XR1 and XR2 for the specific unit. XR1 feeds one 4.16 KV ESF bus (Train A) A04 and XR2 feeds the other 4.16 KV ESF bus (Train B) A06 of the onsite Class 1E AC distribution sy(Offsite circuit #2) is provided by the other stem for each unit.
The second source of 1
offsite power 1
i unit's Reserve Auxiliary Transformers XR1 and XR2 through the train oriented 4.16 KV ESF bus crossties between the two units.
In addition, each class 1E Switchgear can be connected to a third offsite power source via the Unit Auxiliary Transformers by manually removing the link in the isolated phase bus between the Main Generator and the Main 3
transformer of the non-operating Unit and racking-in the a.16 KV circuit breaker which is normally left racked-out 4
(withdrawn) ~into the fully equipped cubicle connected to the Unit Auxiliary transformer of.the same Unit.
3 Each DG must be capable of starting, accelerating to rated speed and voltage, and connecting to its respective ESF bus
+
on detection of bus undervoltage.
This will be accomplished within 10 seconds.
Each DG must also be capable of.
accepting required loads within the assumed loading sequence 1
intervals, and continue to operate until offsite power can be restored to the ESF buses. These capabilities are 1
required to be met from a variety of initial conditions such as: DG in standby with the engine hot, DG in standby with the engine at ambient conditions, and DG operating in a parallel test mode. A DG is considered already operating if the DG vrltage is a 3924 and 5 4796 volts and the frequency 4
is a 58.8 and s 61.2 Hz.
Proper sequencing of loads, including tripping of nonessential loads, is a required function for DG OPERABILITY.
The AC sources in one train must be separate and independent (to the extent possible) of the AC sources in the other train.
For the DGs, separation and independence are l.
complete j.
(continued)
A!
SAN ON0FRE--UNIT 2-B 3.8-4 Amendment No. 127 t
AC Sources-0perating s
B 3.8.1 BASES 1
LC0 For the offsite AC sources, separation and independence are (continued) to the extent practical. A circuit may be connected to more than one ESF bus, with fast transfer capability to the other l
circuit OPERABLE, and not violate separation criteria.
j l
APPLICABILITY The AC sources and associated automatic load sequence timers are required to be OPERABLE in MODES 1, 2, 3, and 4 to 4
ensure that:
a.
Acceptable fuel design limits and reactor coolant pressure boundary limits are not exceeded as a result 4
of A00s or abnormal transients; and b.
Adequate core cooling is provided and containment OPERABILITY and other vital functions are maintained in the event of a postulated DBA.
The AC power requirements for MODES 5 and 6 are covered in LCO 3.8.2, "AC Sources-Shutdown."
ACTIONS A.1 To ensure a highly reliable power source remains with the one offsite circuit inoperable, it is necessary to verify the OPERABILITY of the remaining required offsite circuit on a more frequent basis. Since the Required Action only specifies " perform," a failure of SR 3.8.1.1 acceptance criteria does not result in a Required Action not met.
i However, if a second required circuit fails SR 3.8.1.1, the second offsite circuit is inoperable, and Condition C, for two offsite circuits inoperable, is entered.
A.2 According to Regulatory Guide 1.93 (Ref. 6), operation may continue in Condition A for a period that should not exceed 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. With one offsite circuit inoperable, the reliability of the offsite system is degraded, and the potential for a loss of offsite power is increased, with attendant potential for a challenge to the unit safety (continued)
SAN ON0FRE--UNIT 2 8 3.8-5 Amendment No. 127
AC Sources-Operating B 3.8.1 i
BASES SURVEILLANCE SR 3.8.1.6 (continued)
REQUIREMENTS to maintain an adequate volume of fuel oil in the day tanks during or following DG testing.
In such a case, a 31 day Frequency is appropriate.
i SR 3.8.1.7 See SR 3.8.1.2.
j SR 3.8.1.8-Transfer of each 4.16 kV ESF bus power supply from the nonnal 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 I
engineerin9 Judgment, taking into consideration the unit conditions required to perform the Surveillance, and is intended to be consistent with expected fuel cycle lengths.
Operating experience has shown that these components usually pass the SR when performed at the 24 month Frequency Therefore, the Frecuency was concluded to be acceptable from a reliability stanc point.
This SR is modified by a Note which acknowledges that credit may be taken for unplanned events that satisfy this SR.
i SR~ 3.8.1.9
[
Each DG is )rovided with an engine overspeed trip to prevent damage to t1e engine.
Recovery from the transient caused by the loss of a large load could cause diesel engine overspeed, which, if excessive, might result in a trip of the engine. This Surveillance demonstrates the DG load response characteristics and capability to reject the largest single load without exceeding predetermined voltage.
and frequency and while maintaining a specified margin to the overspeed trip.
For this unit, the single load for each DG is the Auxiliary Feedwater pump and its horse)ower rating is 800 HP. As required by IEEE-308 (Ref. 13), t1e load rejection test is acceptable if the increase in diesel speed I
does not exceed 75% of the difference between synchronous (continued)
. SAN ON0FRE--UNIT 2 8 3.8-18 Amendment No. 127 i
NPF-10/15-483 I
l ATTACHMENT "B" (Existing Specifications) i Unit 3
AC Sources-Operating 3.8.1 l
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY j
NOTE--------------------
All DG starts may be preceded by an engine prelube period.
\\
Verify each DG starts from standby 184 days condition and achieves, in s 10 seconds, voltage a 3924 V,and s 4796 V, and frequency a 58.8 Hz and 5 61.2 Hz.
NOTE------------------
Credit may be taken for unplanned events that satisfy this SR.
M Verify automatic and manual transfer of AC 24 months power sources from the normal offsite circuit to each alternate required offsite circuit.
(continued) i 4
.I (continued)
SAN ONOFRE--UNIT 3 3.8-7 Amendment No. 116
f AC Sources-Operating l
B 3.8.1 l
5 8 3.8 ELECTRICAL POWER SYSTEMS 4
i I
B 3.8.1 AC Sources-Operating i
BASES i
BACKGROUND The Class 1E Electrical Power Distribution System AC sources consist of the offsite power sources () referred or normal.
power sources and alternate (s)), and t1e onsite standb power sources (Train A and Train B diesel-generators (yDGs)).
1 As required by 10 CFR 50, Appendix A, GDC 17 -(Ref.1), the i
design of the AC electrical power system provides independence and redundancy to ensure an available source of power to the Engineered Safety Feature -(ESF) systems.
4 l
The onsite Class 1E AC Distribution System is divided into redundant load groups (trains) so that the loss of any one l
group does not prevent the minimum safety functions from being performed.
Each train has connections to two preferred offsite power sources and a single DG.
One source of offsite power (Offsite circuit #1) for each unit is normally provided through Reserve Auxiliary transformers XR1 and XR2 for the specific unit. XR1 feeds one 4.16 KV ESF bus (Train A) A04 and XR2 feeds the other 4.16 KV ESF bus (Train B) A06 of the onsite Class 1E AC distribution sy(Offsite circuit #2) is provided by the other stem for each unit.
The second source of offsite power unit's Reserve Auxiliary Transformers XR1 and XR2 through the train oriented 4.16 KV ESF bus crossties between the two -
units.
In addition, each class IE Switchgear can be connected to a third offsite power source via the Unit Auxiliary Transformers by manually removing the link in the.
isolated phase bus between the Main Generator and the Main transformer of the non-operating Unit and racking-in the 4.16 KV circuit breaker which is normally left racked-out (withdrawn) into the fully equi) ped cubicle connected to the Unit Auxiliary transformer of tie same Unit.
An offsite circuit includes all breakers, transformers, switches, interrupting devices, cabling, and controls required to transmit power from the offsite transmission network to the onsite Class 1E ESF bus or buses.
Certain required unit loads are returned to service in a predetermined sequence in order to prevent overloading the transformer supplying offsite power to the onsite Class 1E (continued)
SAN ON0FRE--UNIT 3 8 3.8-1 Amendment No. 116'
AC Sources-Operating 8 3.8.1 BASES BACKGROUND Distribution System. Within 77 seconds after the initiating (continued) signal is received, all automatic and permanently connected i
loads needed to recover the unit or maintain it in a safe condition are returned to service via the programmed time interval load sequence.
8 j
The onsite standby power source for each 4.16 kV ESF bus is
[
a dedicated DG. DGs G002 and G003 are dedicated to ESF
{
buses A04 and A06, respectively. A DG starts automatically on a safety injection actuation signal (SIAS) (i.e., low pressurizerpressureorhighcontainmentpressuresignals) or on an ESF bus degraded voltage or undervoltage signal.
After the DG has started, it will automatically tie to its respective bus after offsite power is tripped as a consequence of ESF bus undervoltage or degraded' voltage, independent of or coincident with an SIAS signal. The DGs I
will also start and operate in the standby mode without tying to the ESF bus on an SIAS alone.
Following the trip j
of offsite power, an undervoltage signal strips nonpermanent j
loads from the ESF bus. When the DG is tied to the ESF bus, loads are then sequentially connected to its respective ESF bus by the programmed time interval load sec uence. The sequencing logic controls the permissive anc starting signals to motor breakers to prevent overloading the DG by automatic load application.
In the event of a loss of preferred power, the ESF electrical loads are automatically connected to the DGs in sufficient time to provide for safe reactor shutdown and to mitigate the consequences of a Design Basis Accident (DBA) such as a loss of coolant accident (LOCA).
Certain required unit loads are returned to service in a predetermined sequence in order to prevent overloading the DG in the process. Within 77 seconds after the initiating signal is received, all loads needed to recover.the unit or maintain it in a safe condition are returned to service.
Ratings for Train A and Train B DGs satisfy the requirements of Regulatory Guide 1.9 (Ref. 3). The continuous service rating of each DG is 4700 kW with 10% overload permissible for u) to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> in any 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period. However, for stand)y class of service like the San Onofre DGs the manufacturer allows specific overload values up to 116.1% of continuous duty rating based on the total hours the DG is (continued)
SAN ONOFRE--UNIT 3 B 3.8-2 Amendment No. 116
(
AC Sources-Operating B 3.8.1 BASES BACKGROUND operated per year.
The ESF loads that are powered from the (continued) 4.16 kV ESF buses are listed in Reference 2.
APPLICABLE The initial conditions of DBA and transient analyses in the SAFETY ANALYSES UFSAR, Chapter 6 (Ref. 4) and Chapter 15 (Ref. 5), 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 3.4, Reactor Coolant System (RCS); 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 results in maintaining at least one train of 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.
The AC sources satisfy Criterion 3 of NRC Policy Statement.
LC0 Two qualified circuits between the offsite transmission network and the onsite Class 1E Electrical Power Distribution System and separate and independent DGs for each train ensure availability of the required power to shut down the reactor and maintain it in a sa.fe shutdown condition after an anticipated operational occurrence (A00) or a postulated DBA.
Qualified offsite circuits are those that are described in the UFSAR and are part of the licensing basis for the unit.
i (continued)
SAN ONOFRE--UNIT 3 B 3.8-3 Amendment No. 116
t,;
AC Sources-Operating B 3.8.1 i
i BASES l
LC0 Each offsite circuit must be capable of maintaining rated
.l (continued) frequency and voltage, and accepting required loads during an accident, while connected to the ESF buses.
i One source of offsite power (Offsite circuit #1). for each
'l unit is normally provided through Reserve Auxiliary Transformers XR1 and XR2 for the specific unit. XR1 feeds j
one4.16KVESFbus(TrainA)A04-andXR2feedstheother i
4.16 KV.ESF bus (Train B) A06 of the onsite Class 1E AC l
distribution sy(Offsite circuit #2) is provided by the other stem for each unit. The second source of offsite power.
unit's Reserve Auxiliary Transformers XR1 and XR2 through the train oriented 4.16 KV ESF bus crossties between the two units.
In addition, each class 1E Switchgear can be i-connected to a third offsite power source via the Unit Auxiliary Transformers by manually removing the link in the isolated phase bus between the Main Generator and the Main transformer of the non-operating Unit and racking-in the i
4.16 KV circuit breaker which is normally left racked-out (withdrawn) into the fully equiaped cubicle connected to the Unit Auxiliary transformer of t1e same Unit.
Each DG must be capable of starting, accelerating to rated speed and voltage, and connecting to its respective ESF bus on detection of has undervoltage. This.will be accomplished within 10 seconds.
Each DG must also be capable of accepting required loads within the assumed loading sequence intervals, and continue to operate until offsite. power can be restored to the ESF buses. These capabilities are required to be met from a variety of initial conditions such as: DG in standby with the engine hot, DG.in standby with the engine at ambient conditions, and DG operating in a parallel test mode. A DG is considered already operating if the DG voltage is a 3924 and s 4796 volts and the frequency is a 58.8 and s 61.2 Hz.
Proper sequencing of loads, including tripping of nonessential loads, is a required function for DG 1
1 The AC sources in one train must be separate and independent (to the extent possible) of the AC sources in the other train. For the DGs, separation and independence are complete.
(continued)
SAN ON0FRE--UNIT 3 B 3.8-4 Amendment No. 116
AC Sources-Operating B 3.8.1 BASES LC0 For the offsite AC sources, separation and independence are (continued) to the extent practical. A circuit may be connected to more l
than one ESF bus, with fast transfer capability to the other circuit OPERABLE, and not violate separation criteria, j
APPLICABILITY The AC sources and associated automatic load sequence timers are required to be OPERABLE in MODES 1, 2, 3, and 4 to ensure that:
a.
Acceptable fuel design limits and reactor coolant pressure boundary limits are not exceeded as a result of A00s or abnormal transients; and b.
Adequate core cooling is provided and containment OPERABILITY and other vital functions are maintained in the event of a postulated DBA.
The AC power requirements for MODES 5 and 6 are covered in LC0 3.8.2, "AC Sources -Shutdown."
ACTIONS A.1 To ensure a highly reliable power source remains with the one offsite circuit inoperable, it is necessary to verify the OPERABILITY of the remaining required offsite circuit on a more frequent basis. Since the Required Action only specifies " perform," a failure of SR 3.8.1.1 acceptance criteria does not result in a Required Action not met.
However, if a second required circuit fails SR 3.8.1.1, the second offsite circuit is inoperable, and Condition C, for two offsite circuits inoperable, is entered.
A.2 According to Regulatory Guide 1.93 (Ref. 6), operation may continue in Condition A for a period that should not exceed 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. With one offsite circuit inoperable, the reliability of the offsite system is degraded, and the potential for a loss of offsite power is increased, with attendant potential for a challenge to the unit safety (continued)
SAN ON0FRE--UNIT 3 8 3.8-5 Amendment No. 116
~. _ - _
AC Sources-Operating B 3.8.1 s
I BASES t
l SURVEILLANCE.
SR 3.8.1.6 (continued) i REQUIREMENTS to maintain an adequate volume of fuel oil in the day tanks L
during or following DG testing.
In such a case, a 31 day i
Frequency is appropriate.-
l' SR 3.8.1.7-a J
f See SR 3.8.1.2.
- -~
)
f Transfer of each 4.16 kV ESF bus power supply from the i
normal offsite circuit to the alternate offsite circuit 1
l demonstrates the OPERABILITY of the alternate circuit i
distribution network to power the shutdown loads. The 24 month Frecluency of the Surveillance is based on engineering ;udgment, taking into consideration the unit i
conditions required to perform the Surveillance, and is intended to be consistent with expected fuel cycle lengths.
Operating experience has shown that these components usually pass the SR when performed at the 24 month Frequency.
i Therefore, the Frec uency was concluded to be acceptable from a reliability stanc point.
This SR is modified by a Note which acknowledges that credit may be taken for unplanned events that satisfy this SR.
SR 3.8.1.9 Each DG is )rovided with an engine overspeed trip to prevent damage to tie engine. Recovery from the transient caused by the loss of a large load could cause diesel engine overspeed, which, if excessive, might result in a trip of the engine. This Surveillance demonstrates the DG load response characteristics and capability to reject the largest sir.gle load without exceeding predetermined voltage and frequency and while maintaining a specified margin to the overspeed trip.
For this unit, the single load for each DG is the Auxiliary Feedwater pump and its horse)ower rating is 800 HP. As required by IEEE-308 (Ref.13), t1e load rejection test is acceptable if the increase in diesel speed does not exceed 75% of the difference between synchronous (continued)
SAN ONOFRE--UNIT 3 B 3.8-18 Amendment No. 116
NPF-10/15-483 d
f ATTACHMENT "C" (Proposed Specifications)
Unit 2
=
AC Sources-Operating 3.8.1 SURVEILLANCE REQUIREMENTS i
SURVEILLANCE FREQUENCY SR 3.8.1.7
NOTE--------------------
All DG starts may be preceded by an engine prelube period.
Verify each DG starts from standby 184 days l
condition and achieves, in 5 10 seconds, voltage a 3924 V and 5 4796 V, and frequency a 58.8 Hz and 5 61.2 Hz.
NOTES-----------------
i 13 Credit may be taken for unplanned events that satisfy this SR.
2 f.'~^~ Te's ti rig ~to"Tati s ff' thi s" SR ' Wha l T
^~ "~" include' actual' automatic and: manual 24 months
' transfer, to >at:least,one al ternate' offsite circuiti The'other alternate
^ ffsite circuit may,'be varified ~by;'"'"
o overjapping,ci rcui t tests ;"~"""-
i i
Verify [spitiility*ghf automatic and manual y
transfer of'^C power sources from the normal offsite circuit to each alternate required offsite circuit.
J (continued)
SAN ONOFRE--UNIT 2 3.8-7 Amendment No.
t
=
AC Sources-Operating B 3.8.1 B 3.8 ELECTRICAL POWER SYSTEMS B 3.8.1 AC Sources-Operating i
l BASES t
BACKGROUND The Class 1E Electrical Power Distribution System AC sources consist of the offsite power sources (#6hidi; preferred ee 1
l neraal ihdfaltifnitE?p*refpFFid power s6ufEss" and altern:tf(i))T"shdthe 5iBit3* standby (6WiftE[ power sources j
l (Train A and Train B Diesel Generators"(DGs))'. As required 1
l by 10 CFR 50, Appendii A, GDC 17 (Ref. 1), the design of the AC electrical power system provides independence and redundancy to ensure an available source of power to the Engineered Safety Feature (ESF) systems.
The onsite Class 1E AC Distribution System is divided into redundant load groups (trains) so that the loss of any one group does not prevent the minimum safety functions from being performed.
Each train has connections to two preferred {offsite)jpowersourcesandasingleDG.
One-IWiM6ddi?1?thf6'6thi4F*thsiW6riid17pFsfEFFidlyssif source M 6fMit?
P(O f f si t~e c i FEu i t*11 )"fo F"esch* dui t"i s nc = lly pr vided thr ugh Reserve Auxiliary transformers XR1 and XR2 for the specific unit. XR1 feeds one 4.16 kV ESF bus (Train A) A04 and XR2 feeds the other 4.16 kV ESF bus (Train B) A06 of the onsite Class 1E AC distribution system for each unit. The ::::nd EltFFhitdT 6
source cf Off:ite p= r (Offsite ciF60f t"y2)'pfsfEFFEdl7pJdg* the is7FP!f3 otherunit'sReserveAuxiliaryTransformersXR1andXR2R6Fj thdT6tfiifTshitrstuhit?AnKilfiryITF&hifshdEBXU1 through"the t'Esth*6Frintid*4".'16*kV"ESF"60sTr6isti^es"bsWssn the two units. Thd?4716?kV!ESF;blis?hlF (ditifmihesnhiehlitfinsfdrmeli(s)s#hdishEfW!thdI6th^EEI serVesfiilths141tunais preferrid ?p6ssMihafeehilfstheE4i>16s kVj ESES bJsfi6f thsF6thif ini tns?ali hneditsitheiRisefssYAniliatyiTfinsf6rM(XR1 Eof XR2)Hthsntthit}tfinsf6fseriisitheifequffedfaltehate ~"""
pfefeffsdij6ssMsdupesMIfsthh4ill'61kVsESMbbsOn!thdT6this unitMs[ititransfal ignent0%thsiUhi tiAbill i hrisTEirisfo rmsM g g gggg g ( f6rserils?then sy g pm?ilternitsjpf then%th eferred
~~ ~.- -
~~~
In cdditi:n,'1hiM6ddii5?sWdI6%^shihithENiiHTsE66 Fit 6FEi5?h6t1 e a c h* Cl is~i'I E"SQi t 6ge a F~da d' bs~E o n set te d
- t 6T~^"
6pErating) tite p"fEfdrfid power source via the Unit Auxiliary thifdSf.
Transformers by inshu~ ally removing the linki in the isolated phase bus between the Main Generator and the Main (continued)
SAN ONOFRE--UNIT 2 8 3.8-1 Amendment No. 127
AC Sources-Operating B 3.8.1 i
BASES BACKGROUND transformer of the non-operating (H6ddC5Ysh'dI6 Unit and bl~6KiWyrecking in the 4.16 kV circdit'bFsikin[. ich ic (continued)
Ei-51 Ly !cft rccked cet Nithdr=n) int the fc!!y -
cubicle cenaccted to the Unit Auxiliary transformer o?ci: ped t ie Trans. Uni t. ilW!thigsllfviisihQthQdi tifAbif]Tiyy__fe_rgj same formeGjXVI)Rservesyasgthe?requiregaltegnate;pge PA H g ouyg g{p g g yJSg b y ej,Ejg g eg geg g lig j
An offsite circuit includes all breakers, transformers, switches, interrupting devices, cabling, and controls required to transmit power from the offsite transmission network to the onsite Class 1E ESF bus or buses.
Ce.ctain required unit loads are returned to service in a predetermined sequence in order to prevent overloading the transformer supplying offsite power to the onsite Class 1E Distribution System. Within 77 seconds after the initiating signal is received, all automatic and permanently connected loads neeed to recover the unit or maintain it in a safe condition are returned to service via the programmed time interval load sequence.
The onsite standby power source for each 4.16 kV ESF bus is a dedicated DG. DGs G002 and G003 are dedicated to ESF buses A04 and A06, respectively. A DG starts automatically on a safety injection actuation signal (SIAS) (i.e., low pressurizer pressure or high containment pressure signals) or on an ESF bus degraded voltage or undervoltage signal.
After the DG has started, it will automatically tie to its respective bus after offsite power is tripped as a consequence of ESF bus undervoltage or degraded voltage, independent of or coincident with an SIAS signal.
The DGs will also start and operate in the standby mode without tying to the ESF bus on an SIAS alone.
Following the trip of offsite power, an undervoltage signal strips nonpermanent loads from the ESF bus. When the DG is tied to the ESF bus, loads are then sequentially connected to its respective ESF bus by the programmed time interval load secuence.
The sequencing logic controls the permissive anc starting signals to motor breakers to prevent overloading the DG by automatic load application.
In the event of a loss of preferred power, the ESF electrical loads are automatically connected to the DGs in sufficient time to provide for safe reactor shutdown and to mitigate the consequences of a Design Basis Accident (DBA) such as a loss of coolant accident (LOCA).
(continued)
SAN ON0FRE--UNIT 2 8 3.8-2 Amendment No. 127
AC Sources-Operating 8 3.8.1 BASES BACKGROUND Certain required unit loads are returned to service in a (continued) predetermined sequence in order to prevent overloading the DG in the process. Within 77 seconds after the initiating signal is received, all loads needed to recover the unit or.
maintain it in a safe condition are returned to service.
Ratings for Train A and Train 8 DGs satisfy the requirements of Regulatory Guide 1.9 (Ref. 3). The continuous service rating of each DG is 4700 kW with 10% overload permissible for u) to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> in any 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period. However, for standay class of service like the San Onofre DGs the manufacturer allows specific overload values up'to 116.1% of continuous duty rating based on the total hours the DG is operated'per year.
The ESF loads that are powered from the 4.16 kV ESF buses are listed in Reference 2.
APPLICABLE The initial conditions of DBA and transient analyses in the SAFETY ANALYSES UFSAR, Chapter 6 (Ref. 4) and Chapter 15 (Ref. 5), 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 3.4, Reactor Coolant System (RCS); 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 results in maintaining at least one train of 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.
The AC sources satisfy Criterion 3 of NRC Policy Statement.
(continued)
SAN ONOFRE--UNIT 2 8 3.8-3 Amendment No. 127
0 e
AC Sources-0perating B 3.8.1 BASES 4
LC0 Two qualified circuits between the offsite transmission network and the onsite Class 1E Electrical Power Distribution System and separate and independent DGs for each train ensure availability of the required power to shut i
down the reactor and maintain it in a safe shutskwn condition after an Anticipated Operational Occurrence (A00)-
i or a postulated DBA.
Qualified offsite circuits are those that are described in the UFSAR and are part of the licensing basis for the unit.
REQU1FsdBiff si tQ11F2Hitifi^fE5th5WEIEf rEUi;ti5thatYifi SEej}egajdjgegugyditggejppeyaplg1 peg [L,CQ8jl]"'
Each FsijdifEd offsite circuit must be capable of maintaining eated"frsquency and voltage WithfhispEdifidd311 sit'i, and acce ating required loads dur'ing*hn"scEidEht~"^Ghili" connected to t1e ESF buses.
1 One-IHTM5; dss!n?*'(0ffsite"di^rbuit71) 'f6F" isch"y6^ ER source 1sthP5BiWI4EthiiH3FiihTyFififfEd G
- f ffiitd"pi uni t~is n0mally pr0vided through Reserve Auxiliary Transformers XR1 and XR2 for the specific unit. XR1 feeds one 4.16 kV ESF i
bus (Train A) A04 and XR2 feeds the other 4.16 kV ESF bus (Train B) A06 of the onsite Class 1E AC distribution system for each unit. The :econd alternate preferred power source other unit'pc cr (Offsite circuit #2) is prcvid.d by the cf Offsite s Reserve Auxiliary 'Tra55fo'rmer'XU1 through^the the"oth'eFU6it's"Un~it"Adxiliar, Transformers XR1 and XR2;"~oij y
train ~ oriented 4.'16'kV^ESF bus crossties ~beWee'n the two units. Th~e"4:16^'kV"ESF' bus 'ali defsreines which transformer (s)gniriehtin"the otheF'uhit serves as the' alternate preferred power source.s If the 4.16 kV ESF bus in the dthe'f unit'is aligned to the, Reserve Auxiliary Transformer (XRI' of XR2),: then,that transformer is the required alternate ~~'~'
preferred power source., If the 4.16 kV ESF bus in thd*Bth' f, e
unit is aligned to the Unit' Auxiliary Transformer,(XU1)f"*'
then that transfonner is the required' alternate preferred Ppwerjourcej- "' "~ ^'~^'^~' ~^
' " " " " ~ ~ ~ ~ ^ ^ ' ~ ' ~ ~ ~ " ~ " " ' ~ " "
In additien, IWTH6dsiT573HdI6HshE5?tfisTiiiiH's~si5EfitHETs h3tibpTFit i nji'E sc h"Cl ass"1 E" Sni ts hghsF'c s n* b e"c o h ns c fsd"t o i~ third"5ffL te pFEfsFFFd power source via the Unit Auxiliary Transformers *by manually removing the linki; in the isolated phase bus between the Main Generator and ths Main transformer of the non-operating ;(M6dsi?STsn^d[6 Unit and
[165@ racking in the 4.16 kV circuit"brehkerl[ich in (continued)
SAN ONOFRE--UNIT 2 8 3.8-4 Amendment No. 127
a AC Sources-Operating c
B 3.8.1 BASES LC0
- = lly left r :ked ::t (withdr: n) int: the fe!!y :~ai: ped (continued)
- bi:!: ::::::ted to the Unit Auxiliary transformer of t1e same Unit. IWiftM1761fiiisiE^rit!9thEUhi.tTAniTiki9 TFHifdHiiiE2(fs)d8'1ggpssys)i@gni fedihl tiphatiiQiffir;iWd XU1 iservesifasythelre N5$$NsNN5 ig{(pgjylpgitj
.Each DG must be capable of starting, accelerating to ratedspeed and volta ective ESF busondetectionofge,andconnectingtoitsresge us undervoltage.
This will accomplished within 10 seconds. Each DG must also be capable of accepting required loads within the assumed loading sequence intervals, and continue to operate until offsite power can be restored to the ESF buses.
These capabilities are required to be met from a variety of initial conditions such as: DG in standby with the engine hot, DG.in standby with the engine at ambient' conditions, and DG operating in a parallel test mode. A DG is considered already operating if the DG voltage is a 3924 and s 4796 volts and the frequency is a 58.8 and s'61.2 Hz.
Proper sequencing of loads, including tripping of nonessential loads, is a required function for DG OPERABILITY.
The AC sources in one train must be separate and independent (to the extent possible) of the AC sources in the other train.
For the DGs, separation and independence are complete.
l For the offsite AC sources, separation and independence are to the extent practical. A circuit may be connected to more than one ESF bus, with ht-transfer capability to the other circuit OPER?SLE, and not violate ESRbus separation
~~'""
criteria.
APPLICABILITY The AC sources and associated automatic load sequence timers are required to be OPERABLE in MODES 1, 2, 3, and 4 to ensure that:
1 a.
Acceptable fuel design limits and reactor coolant pressure boundary limits are not exceeded as a result of A00s or abnormal transients; and (continued)
-SAN ON0FRE--UNIT 2 B 3.8-5 Amendment No. 127
=-
a AC Sources-Operating B 3.8.1 BASES i
SURVEILLANCE SR 3.8.1.6 (continued)
REQUIREMENTS to maintain an adequate volume of fuel oil in the day tanks during or following DG testing.
In such a case, a 31 day Frequency is appropriate.
i SR 3.8.1.7 J
See SR 3.8.1.2.
Trr.:fer cf Verifithti6n'"'of"ths^ chpability'tB"trais'fEf each 4.16 kV ESF bus ' power" supply *from' the normal ^' preferred"p'use~f so~u~rce^'(offsite circuit)(offsite circuit), via~ths~triiWi to ee-each' re~quirdd ~ alternate' ~~'
preferred' posef ~s6Urce
aligned 4.16' kv crosstie b'etWeeh' Unit" 2 and Unit 3,r^^*'~^'"
demonstrates' the" 0PERABILITY~of' the ' al ternate '~;ircui t 4
p' refer'rsd'p6w^eri distribution network to )ower the 'p6st9 accident and shutdown loads. For~ 2A04 tie no'rmal' offsiti
~
power source is^2XR1',an'dthe~"' alternate offsite power souFd^i
^
is 3XR1 or,3XU1. ' For 2A06 the normal' offsite power, s'ource'~'
is'2XR2, and^the alternate offsite power" source;is 3XR2 o 3XU1.' A required: alternate offsite power' source'is'the'~g source that.is' credited'as'the alternate source of offsits power in LCO '3.8.It sTherefore, the, alignment of the ESE~~
buses 'in Unit'3 detemines' which alternate offsite> circuit' is;,the'lequiye,d ciycuj,(at any ppint in' timej~'~^~~^^~~~~~~~~
F6~f~esch'"4~.'16^ kV"ESF/has'^(2A04 ~6r^ 2A06)~this~~s^JWiillinud requirement may be satisfied by performing both'a' manual'
' source to at< least one of' the alternate offsite power ~' "~~~,rj transfer and an auto-transfer from the normal offsite poid
^ The tested source may, then be_ credited as ths sources.
requir;ed alternate;offsite power source per LCO'.3.8.1.'^ This surveillance may be satisfied for the' remaining power,' source by' performing,a circuit. functional test in addition' to the"~
transfer test above. 'Thissfunctional; test'shall'be*~'~"~~~
performed such that+ all components that'are required ^td
~
function for a successful manual or auto-transfer that:EdFE not included in the transfer tests above, are tested i his T
testing may include any series of sequential, overlapping;~
or total steps'so;that the entire manual and acto'-transfer capability of the source is verified., This>is explained i6
~ ~ ~ _to this S.R!.~~
' ~ ' ~ ~ ' ^ " ~
^ ~ ^ " ^ ~ ~ ~ '
a note
~ -.. -
(continued)
SAN ON0FRE--UNIT 2 8 3.8-18 Amendment No. 127
. r HPF-10/15-483 ATTACHMENT "D" (Proposed Specifications)
Unit 3 I
1 l
l l
AC Sources-Operating i
3.8.1 REQUIREMENTS i
SURVEILLANCE I
FREQUENCY SR 3.8.1.7
NOTE--------------------
All DG starts may be preceded by an engine prelube period.
Verify each DG starts from standby 184 days condition and achieves, in s 10 seconds, voltage t 3924 V and s 4796 V, and frequency a 58.8 Hz and s 61.2 Hz.
NOTES-------------------
17 Credit may be taken for unplanned events
"" that satisfy this SR.
I 2:'"Tisti ng ' to sati sfi~ thi s"SR"'shal l Tidcl uds
'~~' actual' automatic and man'ual transfer'to~'
24 months
'at least one' alternate;'offstte:'dircuitil The 'other, alternate of fstte' may be'~^~~'
3
- ver,i f,l ed ' by ove rl appi ng gi rcui t
__________________________________i__teiti]
1 Verify $1pibilpf!6f; automatic and manual transfer of*AC power sources from the normal offsite circuit to each alternate required offsite circuit.
(continued)
A i
(continued)
SAN ONOFRE--UNIT 3 3.8-7 Amendment No.
. i 4
AC Sources-Operating 8 3.8.1 j
83.8 ELECTRICAL POWER SYSTEMS i
-B 3.8.1 AC Sources-Operating
}
i BASES 1
BACKGROUND The Class-1E Electrical Power Distribution System AC sources i
i consist of the offsite, power sources (h'6hiil preferred ee n =1 :ihdIditVFhitEYp*refiffid power s6Efees and j
- 1t:=tME))Tsud*the5EsitFstandby;(6hiitE{powersources (Train A and Train B Diesel Generators,(DG5)). As required t
i by 10 CFR 50, Appendii A, GDC 17 (Ref. 1), the design of the AC electrical power system provides independence and 4
i-_
redundancy to ensure an available source of power to the Engineered Safety Feature (ESF) systems.
t l
The onsite Class 1E AC Distribution System is divided into i
redundant load groups (trains) so that the loss of any one j
group does not prevent the minimum safety functions from being performed.
Each train has connections to two preferred {offsite{powersourcesandasingleDG.
e One-IH'M6disTI?thE6'GihT4',]tf?20it*#1)pfififfidy6Whi source th67hbiissTT Of ?fsitFp!?*(0ffsite
'fdF~ssEh*uhit*is nc = lly p = ided th = gh Reserve Auxiliary transformers XR1 and XR2 for the specific unit. XR1 feeds one 4.16 kV ESF i
bus (Train A) A04 and XR2 feeds the other 4.16 kV ESF bus (Train B) A06 of the onsite Class 1E AC distribution systein I
i for each unit.
The :: end iTtifristii Fwd
- r (Offsite ciF6Hft~#2)"pFETiFPidTg5%y source j
ef eff:it:
is1???rd the i
other unit's Reserve Auxiliary Transformers XR1 and XR2776Tj thiT6thsynhttIW7UWit?AnillTiry}jTfdhif6fliEVZXUli through"tNE i
gg.iffstFd"4716*kV"ESF"biis'cr6YstfEI"EsNsin the two units.
ThiT4716EkVIESPbui?il ighisiht%paisthiyalterhats fWIthE76thiqUWIf
'ditifiiriss$"w"eYiosfEeMIfjthel4f16tl@;;ESFjbsstih5thsf6th hibhistransf6pme~r(s)ssefyss pysfsppidy whidTsiaipolineditolthelRis'eris XR2)Mthsethit{tfansfopier$ s?Auiiliarygiransf6piiri(glji@
i-ithsWi"nipedisifsFnsts" Fiferri' ?p~o^%eBibirdsiSIfiths!4?16 ESubusUhittiiT6the]
(sit %iffilis6sd7t'6fths%UnittAnil
}f d
2 9 2ar m ((ff g jp g g e g gu _ g gatg jfe eyy
~
u r
.XUl t W i ( p trs th 4'
!n :ddition,IhiM6ddil5?fiddQ,9hiWith67iisi'hYsE66Yif6ffli?Tidt 6p~ifitihg? eidh"C1"sss"1E"SettthissFts*be~6onn'dathd*tPA thiFd"Bf.:'ite (*Peferfid power source via the Unit Auxiliary i
i Transformers by ininsiTTy removing the links; in the isolated i
phase bus between the Main Generator and the Main a
(continued) 4 j
SAN ON0FRE--UNIT 3 B 3.8-1 Amendment No. 116 i
n.. -
~
=
,i...'
i
+
i
..e.
AC Sources-Operating 8 3.8.1 l-i BASES BACKGROUND transformerofthenon-operating:(Hsdss!5?sdI6[fSi:
+
Unit and (continued)
Elis F ra:Eing in the 4.16 kV circilit^bVWik'sf"E NA i
left r: hed :t (:ithdr= ) int the fully :-
- bicle ::::::ted to the Unit Auxiliary transformer o?ci g:d t ie hoggsigd3f(XUI)isiNss%gishdyi$gjpg)gp i
same Unit.
TFihif6HiiiiF3 dthiEpquitidisitiphu ggggggg i
An offsite circuit includes all' breakers, transformers, switches, interrupting devices, cabling, and controls I
required to transmit power from the offsite transmission j
j network to the onsite Class 1E ESF bus or buses.
7' Certain required unit loads are returned to service in a predetermined sequence in order to prevent overloading the i
transformer supplying offsite power to the onsite Class 1E j
Distribution System. Within 77 seconds after the initiating signal is received, all automatic and permanently connected loads needed to recover the unit or maintain it in a safe condition are returned to service via the programmed time 3
interval load sequence.
The onsite standby power source for each 4.16 kV ESF bus is a dedicated DG. DGs G002 and G003 are dedicated to ESF buses A04 and A06, respectively. A DG starts automatically on a safety injection actuation signal (SIAS) (i.e., low 4
pressurizer pressure or high containment pressure signals) i or on an ESF bus degraded voltage or undervoltage signal.
After the DG has started, it will automatically tie to its respective bus after offsite power is tripped as a consequence of ESF bus undervoltage or degraded voltage, independent of or coincident with an SIAS signal. The DGs will also start and operate in the. standby mode without tying to the ESF bus on an SIAS alone.
Following the trip of offsite power, an undervoltage signal strips nonpermanent loads from the ESF bus. When the DG is tied to the ESF bus, loads are then sequentially connected to its respective ESF bus by the programmed time interval load secuence.
The sequencing logic controls the permissive anc starting signals to motor breakers to prevent overloading the DG by i
automatic load application.
In the event of a loss of preferred power, the ESF electrical loads are automatically connected to the DGs in sufficient time to provide for safe reactor shutdown and to mitigate the consequences of a Desi n Basis Accident (DBA) i such as a loss of coolant accident LOCA).
(continued)
SAN ONOFRE--UNIT 3 B 3.8-2 Amendment No. 116
a r e AC Sources-Operating B 3.8.1 I
I' BASES BACKGROUND Certain required unit loads are returned to service in a (continued) predetermined sequence in order to prevent overloading the DG in the process. Within 77 seconds after the initiating t
signal is received, all loads needed to recover the unit or maintain it in a safe condition are returned to service.
[
Ratings for Train A and Train B DGs satisfy the requirements of Regulatory Guide 1.9 (Ref. 3). The continuous service c
rating of each DG is 4700 kW with 10% overload permissible i
for u) to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> in any 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> period.
However, for stand)y class of service like the San Onofre DGs the manufacturer allows specific overload values uo to 116.1% of continuous duty' rating based on the total hours the DG is operated per year. The ESF loads that are powered from the 4.16 kV ESF buses are listed in Reference 2.
APPLICABLE The initial conditions of DBA and transient analyses in the SAFETY ANALYSES UFSAR, Chapter 6 (Ref. 4) and Chapter 15 (Ref. 5), 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 3.4, Reactor Coolant System (RCS); and Section 3.6, Containment Systems.
1 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.
inis results in maintaining at least one train of 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.
The AC sources satisfy Criterion 3 of NRC Policy Statement.
4 (continued)
SAN ON0FRE--UNIT 3 8 3.8-3 Amendment No. 116
AC Sources-Operating j
=
B 3.8.1 BASES e
l LC0 Two qualified circuits between the offsite transmission i
network and the onsite Class 1E Electrical Power Distribution System and separate and independent DGs for each train ensure availability of the required power to shut down the reactor and maintain it in a safe shutdown condition after an Anticipated Operational Occurrence (A00) or a po'tulated DBA.
i Qualified offsite circuits are those that are described in the UFSAR and are t of the licensing basis for the unit.
4 l
Req _ditudf.v...h...d....i..f...e.,g.,!E uiTe~disffifth itiTEFilth3iV %ildiiis%th~ ~ P
^51 Ere a
ui siti4I0pe...f...a.b...l.e..otpe#1N., 3 1
wymgg ygggy
.m 4
~.=:
y, g y y
et-ed"f(rsijuEHey and voltage Eithili{spibifiEdliffiY#, andEac i
i acce) ting required loads durtny"aii acifdeht7"GhiWconnected i
to t1e ESF buses.
t one-1WiM6diiB17thF6EiWE4M*thiT5EfsETTpFEfiffidTp^ Wit is 5iffij source efO'fffMPfff!P"(OffsitedTFEUit*ll)iliaryTransformersXR1 3
f6Peleh*d n:- =y previded through Reserve Aux p
and XR2 for the specific unit.
XR1 feeds one 4.16 kV ESF bus (Train A) A04 and XR2 feeds the other 4.16 kV ESF bus (Train B) A06 of the onsite Class 1E AC distribution system for each unit.
The ::::nd alternate of eff ite p=:r (Offsite circuit #2) preferred power source
^
is pr:vid.d by the.
other unit's Reserve Auxiliary Transformers XR1 and XR2p^;Tr^
i t;WiK6thiffshiQs;U6ftQUff}Ti@[ijifsfEEH}g through the; i
tFiin*"0HE6 tid 4.16"kV ESF bGs crossties listween the two units. ThEJ4716TkVJESEstiGiYiirihEEhtifWithET5tlidWiidit ditEWiiiiiestWii clistsihtfasid(he?4316s.kV5 ESEjbhW3Mthd7 s)nsirsistasitheisitsensfi I
ppsfiFFid56ntisbufsiisdifft
~
hil tFisfsli ghidit03ths$RissrysIAsiilfsfpJradiformef3
)(R2$thehithit{tpshsfo&nfis$thdWsqutridtslisFWitiP(XR1!6W preferfed@def!5shresMM fgth;el41161kVIESEsbus$hiftiseWJij uni tyisfih gheditditheIU6i t4uiiil.iify3TPahif6fiet[(fgg)!]
XU1 M(nithjyftgfgggj$hjyjQigdpl{ej@{eyj3 g
powerssou_rce.
-m j.
i In :dditien THEM6 dei!5Tisd!6EinfishifEEiiilififhgeneratifEf3 fi6E6pififlIj7EWch"Cl ais*'1E'SWith hisii'""diff"be*E0nnedYed"t o l'
4" thiry 5ffEt pFi^fiffid power source via the Unit i
Auxiliary TransfoFmiF5"by manually removing the linki in the i
isolated phase bus between the Main Generator and ths Main ElFild{ racking'in the 4.16 kV circuit"b]reak'sfgich i:
transformerofthenon-operating;(M6 dei 57Ehd Unit and i
- j (continued)
SAN ON0FRE--UNIT 3 8 3.8-4 Amendment No. 116
-- - -.--.- - ~- -..
.h AC Sources-Operating B 3.8.1 BASES LC0
--ly left r::hed ::t (withdr:: ) int the fully ci: ped (continued)
- Siel: ::::::t:d to the Unit Auxiliary?A E11TiWtransformer c7 same Unit. 15TthTiT3HJ6iiisstWthiiU61t Rihsffdiiigxul)gelESfjpp@s)2jgMpsjpeggQhhirissisisth P2SIjsjugcejfgg
-Each DG must be capable of starting, accelerating to ratedspeed and voltr busondetectionof$a,andconnectingtoitsres)ectiveESF us undervoltage.
This will
)e accomplished within 10 seconds.
Each DG must also be capable of accepting required loads within the assumed loading sequence irtervals, and continue to operate until offsite power can be restored to the ESF buses.
These capabilities are required to be met from a variety of
-initial conditions such as: DG in standby with the engine hot, DG in standby with the engine at ambient conditions, and DG cperating in a parallel test mode. A DG is considered already operating if the DG voltage is a 3924 and s 4796 volts and the frequency is a 58.8 and s 61.2 Hz.
Proper sequencing of loads, including tripping of nonessential loads, is a required function for DG OPERABILITY.
The AC sources in one train must be separate and independent (to the extent possible) of the AC sources in the other train.
For the DGs, separation and independence are complete.
For the offsite AC sources, separation and independence are i
to the extent practical. A circuit may be connected to more than one ESF bus, with M 4-transfer capability to the other circuitOPEPASLE,andnotviolate{Sgbujseparation criteria.
APPLICABILITY The AC sources and associated automatic load sequence timers are required to be OPERABLE in MODES 1, 2, 3, and 4 to ensure that:
a.
Acceptable fuel de' sign limits and reactor coolant pressure boundary limits are not exceeded as a result of A00s or abnormal transients; and (continued)
SAN ON0FRE--UNIT 3 8 3.8-5 Amendment No. 116
j,.
ea
.U'*
AC Sources-Operating B 3.8.1 BASES SURVEILLANCE SR 3.8.1.6 (continued)
REQUIREMENTS to maintain an adequate volume of fual oil in the day tanks during or following DG testing.
In iuch a case, a 31 day Frequency is appropriate.
SR 3.8.1.7 See SR 3.8.1.2.
-T=fer of VFrific'atidh~of'the^^ ^apabilityJts"tFihsfe^f each c
4.16 kV ESF bus'^ power"supplf" from' ths"ndrmal'~ preferred ~p~6s]e soWcF"(d~p'bsFrsF#cF'(offsite circuit), via~th^ tlFiin:
offsite circuit) to ee-Fich"Fe(si^Nd ' Sit'Frnate preferre e
aligned 4.16:ky crosstieb~etWFe~nUriit' 2 and Unit ~3/~"~~^'*
' demon's t rat e s ^ the'0PERABIL'ITY 'o f^the *al te rna te^ c i r:di t i
.accidentrand'sh;utdown1oads.prefeVrsd pbWer distribution network
)ower the ~pbst'J For"2A04;t ie~^~n6~iiiiilPoffsite power' source is' 2XR1',"und 'the~~ alternate offsite power < souRE
~
is 3XR1 or'3XU1,: For'2A06 the: normal loffsit'e power: source"
is ' 2XR2,< and the,al ternate'! of fsite' power, source l'isi 3XR2 'ori 3XU1. ' A required;asternate offsite: power source'is?the^"
source that is credited as1the alternate' source of/dffsitj
^
power in LC01.8.1. <'Therefore, 'the ' alignments oftheESFi ous'esin Unit;3;determinek which alternate offsite^c'ircuit is je requi re d3i rc u i t3t_anLpo i n til n t i nef'"~*'" '~ ^""~~
For'lich4':16~ kV' ESF~ b~si'~(3A04 "oF3A06)" thii^ssWe^ il lihEs requirement may be satisfied by performing'both~'a'~ma'nual" transfer and'an auto-transfer fron'the/ norma 1'offsite po^ifj s
source to at least','one 'of'the, alternate offsite power ~ "~
'ources. The tested source may then be ' credited ~as thi s
required alternate offsite' power' source'per LCO 3.8.'1./ Tliis surveillance may be satisfied for the remaining power source by, performing a circuit' functional test'in a'ddition to the~^^
transfer test' above.' This functional,' test shall3be~^"~'^"^^
performed such that all components that are, required ~td i
function for a successful manual or. auto-transfer that sere not included in the transfer tests 'above, are tested !This testing may', include any series of seque'ntial,<overlappingT or total steps so that;the entire manual and auto-transfer capability of'the source is verified.
This is explained 'iri a ' n o t eJo,, t h i s SR (^"~~~""~ ' ^~~ *' ^ ~' "~ ^^"~^ ~ ~~ ~~ ~ ~ ""~ ~^
(continnd)
SAN ON0FRE--UNIT 3 B 3.8-18 Amendment No. 116