ML14071A152
ML14071A152 | |
Person / Time | |
---|---|
Site: | Sequoyah ![]() |
Issue date: | 03/13/2014 |
From: | Tennessee Valley Authority |
To: | Lisa Regner Plant Licensing Branch II |
Regner L | |
References | |
Download: ML14071A152 (30) | |
Text
Sequoyah Nuclear Plant Nuclear (SQN)
ITS P Project j
Electrical Systems y Presentation March 13, 2014
Agenda Nuclear 3/4 Purpose p of Proposed p Changes g
3/4 Shutdown Board Maintenance 3/4 SQN Electrical Design g
3/4 Current Technical Specifications (CTS) 3/4 p Improved Technical Specifications p ((ITS))
3/4 ITS Example 3/4 Summary y
Purpose of Proposed Changes Nuclear
- Relax overly restrictive CTS electrical requirements for systems shared between units
- Facilitate Shutdown Board maintenance q g a dual unit outage without requiring g
Shutdown Board Maintenance Nuclear
- Periodic preventive maintenance is required for electrical boards
- Shutdown Boards are shared between Unit 1 and Unit 2
- CTS require a dual unit outage to allow enough time to complete Shutdown Board maintenance
- Current Shutdown Board preventive maintenance has been deferred
Shutdown Board Maintenance Nuclear Changesg Needed to Allow Shutdown Board Maintenance Without a Dual Unit Outageg
- License amendment to allow one ERCW Pump per train
- Plant modification to the auxiliary control air system
- ITS implemented
SQN Electrical Design Nuclear
- The following slides show the SQN electrical system from f the switchyard to the onsite Class 1E distribution system
- There are two load groups, each load group is powered from two 6.9 kV shutdown boards
- Load Groupp A ((1A-A and 2A-A))
- Load Group B (1B-B and 2B-B)
SQN Electrical Design - Normal Alignment Nuclear 161 kV Switchyard (2 busses) 500 kV Switchyard (2 busses)
NC PCBs (2) NC PCBs (2)
Unit 2 Unit 1 CSST C CSST B (Spare) CSST A Main 2 Main 1 LTC LTC LTC LTC LTC LTC GCB GCB USST 2B USST 2A USST 1B USST 1A LTC LTC LTC LTC NC NC NO NO NO NO NC NC Start Bus 1A Start Bus 1B Start Bus 2A St t B Start Bus 2B NC NO NC NO NO NC NO NC (6.9 kV Unit Bds 2A (6.9 kV Unit Bds 1A 6 9 kV Unit Bd 2C 6.9 6 9 kV Unit Bd 2B 6.9 andd 2C are nott shown) h ) andd 1C are nott shown) h ) 6 9 kV Unit Bd 1C 6.9 6 9 kV Unit Bd 1B 6.9 6.9 kV Shutdown 6.9 kV Shutdown 6.9 kV Shutdown 6.9 kV Shutdown Bd. 2B-B Bd. 2A-A Bd. 1B-B Bd. 1A-A DG 2B-B DG 2A-A DG 1B-B DG 1A-A
Safety Related Power Distribution System - Normal Alignment, Both Units in Operation Nuclear DG 2B-B DG 2A-A DG 1B-B DG 1A-A Normal Supply Normal Supply Normal Supply Normal Supply From 2C Unit Bd. From 2B Unit Bd. From 1C Unit Bd. From 1B Unit Bd.
NO NC NO NC NO NC NO NC 6.9 kV 6.9 kV 6.9 kV 6.9 kV Shutdown Shutdown Shutdown Shutdown Bd. 2B-B Bd. 2A-A Bd. 1B-B Bd. 1A-A ERCW** U2 B ESF ERCW** U2 A ESF ERCW** U1 B ESF ERCW** U1 A ESF Loads* Loads* Loads* Loads*
480 V Loads 480 V Loads 480 V Loads 480 V Loads Air Return Fan 2B-B Air Return Fan 2A-A Air Return Fan 1B-B Air Return Fan 1A-A CCS Pump 2B-B CCS Pump 2A-A CCS Pump 1B-B CCS Pump 1A-A CCS Pump C-S** ABGTS Fan A-A** EGTS Fan B-B** EGTS Fan A-A**
ABGTS Fan B-B** Aux Control Air Compressor A-A** CR AHU B-B** CR AHU A-A**
Aux Control Air Compressor B-B** 125 V Vital Batt Chrgr III** 125 V Vital Batt Chrgr II** 125 V Vital Batt Chrgr I**
125 V VitVitall Batt B tt Chrgr Ch IV** 120 V Vit Vitall IInverters t 1 1-III, III 2-III**
2 III** 120 V Vit Vitall IInverters t 1 1-II, II 2-II**
2 II** 120 V Vit Vitall IInverters t 1 1-I, I 2-I**
2 I**
120 V Vital Inverters 1-IV, 2-IV**
Current Technical Specifications Nuclear LCO 3.8.1.1 As a minimum, the following AC electrical power sources shall be OPERABLE:
- a. Two physically independent circuits between the offsite transmission network and the onsite Class 1E distribution system, and
- b. Four separate and independent diesel generators (DGs). . .
APPLICABILITY: MODES 1, 2, 3, and 4.
Current Technical Specifications Nuclear ACTION:
- a. With one offsite circuit inoperable restore offsite circuit within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
b With DGs 1A
- c. With one offsite circuit and one DG inoperable restore one of the inoperable sources within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
- d. With two offsite circuits inoperable restore one offsite source within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
- e. With either DGs 1A-A and/or 2A-A inoperable simultaneously with 1B-B and/or 2B-B inoperable, restore either: 1) 1A-A and 2A A or 2) 1B 2A-A, 1B-BB andd 2B 2B-B.
B . . within ithi 2 h hours.
Current Technical Specifications Nuclear LCO 3.8.2.1 The following AC electrical boards shall be OPERABLE and energized with tie breakers open between redundant boards:
6900 Volt Shutdown Boards 1A-A & 1B-B 6900 Volt Shutdown Boards 2A-A & 2B-B 480 Volt Shutdown Boards 1A1-A, 1A2-A, 1B1-B, & 1B2-B 480 Volt Shutdown Boards 2A1-A, 2A2-A, 2B1-B, & 2B2-B 120 Volt A.C. Vital Instrument Power Board Channels 1-I and 2-I energized from inverters 1-I and 2-I 120 Volt A A.C.
C Vital Instrument Power Board Channels 1 1-II II and 2 2-II II energized from inverters 1-II and 2-II 120 Volt A.C. Vital Instrument Power Board Channels 1-III and 2-III energized from inverters 1-III and 2-III 120 Volt A.C. Vital Instrument Power Board Channels 1-IV and 2-IV energized from inverters 1-IV and 2-IV APPLICABILITY: MODES 1, 2, 3, and 4.
Current Technical Specifications Nuclear ACTION:
- a. With less than the above compliment of AC boards OPERABLE and energized, restore the inoperable boards to OPERABLE status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. . .
Current Technical Specifications Nuclear OPERABLE - OPERABILITY A system, subsystem, train, or component or device shall be OPERABLE or have OPERABILITY when it is capable of performing its specified function(s) function(s), and when all necessary attendant instrumentation, controls, a normal and {emphasis added} an emergency electrical power source, cooling or seal water lubrication or other auxiliary equipment that are required
- water, for the system, subsystem, train, component or device to perform its function(s) are also capable of performing their related support f
function(s).
ti ( )
Current Technical Specifications Nuclear LCO 3.0.5 When a system system, subsystem, subsystem train, train component or device is determined to be inoperable solely because its emergency power source is inoperable, or solely because its normal power source is inoperable, it may be considered OPERABLE for the p purpose p of satisfying y g the requirements q of its applicable pp Limiting Condition for Operation, provided: (1) its corresponding normal or emergency power source is OPERABLE; and (2) all of its redundant system(s),
subsystem(s), train(s), component(s) and device(s) are OPERABLE, or likewise satisfy the requirements of this Specification Specification. Unless both conditions (1) and (2) are satisfied, within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> action shall be initiated to place the unit in a MODE in which the applicable Limiting Condition for Operation does not apply by placing it as applicable in:
- 1. At least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />,
- 2. At least HOT SHUTDOWN within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and 3 At least COLD SHUTDOWN within the subsequent 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />
- 3. hours.
This Specification is not applicable in MODES 5 or 6.
Improved Technical Specifications Nuclear LCO 3.8.1 The following g AC electrical sources shall be OPERABLE:
- a. Two qualified circuits between the offsite t
transmission i i network t k andd th the onsite it Class Cl 1E AC Electrical Power Distribution System; and
- b. Four diesel generators (DGs) capable of supplying the onsite Class 1E AC Electrical Power Distribution System.
APPLICABILITY: MODES 1, 1 22, 33, and 44.
Improved Technical Specifications Nuclear CONDITION REQUIRED ACTION COMPLETION TIME Highlighted portions of ITS Action A reflect CTS A. One offsite circuit A.1 Perform SR 3.8.1.1 for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Action a requirements for inoperable for reasons OPERABLE offsite circuit. the restoration of an other than Condition C. AND inoperable offsite circuit, Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter with the exception that inoperable offsite power AND sources to Shutdown A.2 Declare required feature(s) 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from Board 2A-A or 2B-B are with no offsite power discovery of no offsite available inoperable when power to 6.9 kV addressed in Condition C.
its redundant required Shutdown Board feature(s) is inoperable. 1A-A or 1B-B concurrent with inoperability of redundant required feature(s)
AND A.3 Restore offsite circuit to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> OPERABLE status.
Improved Technical Specifications Nuclear CONDITION REQUIRED ACTION COMPLETION TIME Highlighted portions of ITS Action B reflect CTS B. DG 1A-A inoperable. B.1 Perform SR 3.8.1.1 for the 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Action b requirements for offsite circuits.
circuits OR AND the restoration of inoperable DG(s), with DG 1B-B inoperable. Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter the exception that OR AND inoperable DGs on DGs 1A-A and 2A-A Sh d Shutdown B Boards d 2A 2A-A A
inoperable. B.2 Declare required feature(s) 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> from supported by the inoperable discovery of and 2B-B are OR DG inoperable when its Condition B required redundant concurrent with addressed in Condition D.
DGs 1B-B and 2B-B feature(s) is inoperable. inoperability of inoperable inoperable. redundant required feature(s)
AND B.3.1 Determine OPERABLE 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> DGs are not inoperable due to common cause failure.
OR B.3.2 Perform SR 3.8.1.2 for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> OPERABLE DGs.
AND B.4 Restore DG(s) to 7 days OPERABLE status.
Improved Technical Specifications Nuclear CONDITION REQUIRED ACTION COMPLETION TIME Highlighted portions of ITS Action E reflect CTS E Two offsite circuits E. E1 E.1 Declare required feature(s) 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> from Action d requirements for inoperable. inoperable when its discovery of redundant required Condition E the restoration of an feature(s) is inoperable. concurrent with inoperable offsite circuit.
inoperability of redundant required features AND E.2 Restore one offsite circuit to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> OPERABLE status.
Improved Technical Specifications Nuclear CONDITION REQUIRED ACTION COMPLETION TIME Highlighted portions of ITS Action F reflect CTS F One offsite circuit F. NOTE
NOTE------------------- Action c requirements for inoperable for reasons Enter applicable Conditions and other than Condition C. Required Actions of LCO 3.8.9, the restoration of either "Distribution Systems - Operating," an inoperable offsite AND when Condition F is entered with no AC power source to 6.9 kV power source or a DG, DG 1A-A or 1B-B Shutdown Board 1A-A or 1B-B.
inoperable. ------------------------------------------------
with the exception that combinations involving F.1 Restore offsite circuit to 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> OPERABLE status. inoperable offsite power OR sources and/or DGs to Shutdown Board 2A-A or F.2 Restore DG to OPERABLE status. 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 2B-B are addressed in Conditions G, H or I.
Improved Technical Specifications Nuclear CONDITION REQUIRED ACTION COMPLETION TIME Highlighted portions of ITS Action J reflect CTS J. One or more Train A J.1 Restore one train of DGs to 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> Action e requirements for DG(s) inoperable. OPERABLE status.
the restoration of one AND train of inoperable DGs.
One or more Train B DG(s) inoperable.
Improved Technical Specifications Nuclear CONDITION REQUIRED ACTION COMPLETION TIME ITS Action C contains Required Actions for an C. One offsite circuit C.1 Perform SR 3.8.1.1 for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> inoperable offsite power inoperable solely due to OPERABLE offsite circuit.
an offsite power source AND source to Shutdown to 6.9 kV Shutdown Board 2A-A or 2B-B Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Board 2A-A or 2B-B.
inoperable inoperable. thereafter AND Requires declaring C.2 Declare required feature(s) 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from required features with no with no offsite power discovery of no offsite offsite power available available inoperable when power to 6.9 kV its redundant required Shutdown Board inoperable 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> from feature(s) is inoperable. 2A-A or 2B-B concurrent with discovery of concurrent inoperability of inoperable redundant redundant required feature(s) feature, or 7 days from AND time offsite power source C.3 Declare associated 7 days declared inoperable.
required feature(s) inoperable.
Improved Technical Specifications Nuclear CONDITION REQUIRED ACTION COMPLETION TIME ITS Action D contains Required Actions for an D. DG 2A-A or 2B-B D.1 Perform SR 3.8.1.1 for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> inoperable DG to inoperable inoperable. OPERABLE offsite circuit(s). AND Shutdown Board 2A-A or Once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> 2B-B.
thereafter AND Requires declaring required i d ffeatures D.2 Declare required feature(s) 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> from supported by the inoperable discovery of supported by the DG inoperable when its Condition D redundant required concurrent with inoperable DG inoperable feature(s) is inoperable. inoperability of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> from discovery of redundant required feature(s) concurrentt inoperable i bl AND redundant features, or 7 days from time DG D.3.1 Determine OPERABLE 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> DGs are not inoperable due declared inoperable.
t common cause failure.
to f il OR D.3.2 Perform SR 3.8.1.2 for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> OPERABLE DGs.
AND D.4 Declare associated 7 days required feature(s) inoperable.
Improved Technical Specifications Nuclear CONDITION REQUIRED ACTION COMPLETION TIME ITS Action G contains requirements related to a G One offsite circuit G. G1 G.1 Declare required feature(s) 7 days combination of an inoperable solely due to on associated Unit 2 6.9 kV an offsite power source Shutdown Board inoperable offsite power to 6.9 kV Shutdown Board 2A-A or 2B-B inoperable. source to Shutdown inoperable. Board 2A-A or 2B-B with AND an inoperable Unit 1 DG.
DG DG 1A-A or 1B-B inoperable. Required Action for declaring required features supported by the inoperable DG or offsite circuit inoperable with concurrent inoperable redundant features are addressed in ACTIONS A, B, C, and D, as applicable.
Improved Technical Specifications Nuclear CONDITION REQUIRED ACTION COMPLETION TIME ITS Action H contains requirements related to a H. One offsite circuit H.1 Declare required feature(s) 7 days combination bi ti off an inoperable for reasons on associated Unit 2 6.9 kV other than Condition C. Shutdown Board inoperable offsite power AND inoperable. source to Shutdown Board 1A-A or 1B-B with DG 2A-A 2A A or 2B 2B-BB inoperable. an inoperable i bl U Unitit 2 DG DG.
Required Action for declaring required f t features supported t d by b the th inoperable DG or offsite circuit inoperable with concurrent inoperable redundant d d t features f t are addressed in ACTIONS A, B, C, and D, as applicable.
Improved Technical Specifications Nuclear CONDITION REQUIRED ACTION COMPLETION TIME ITS Action I contains requirements related to a I. One offsite circuit --------------------NOTE-------------------
combination of an inoperable inoperable solely due to Enter applicable Conditions and offsite power source and DG an offsite power source Required Actions of LCO 3.8.9, to Shutdown Board 2A-A or to 6.9 kV Shutdown "Distribution Systems - Operating,"
Board 2A-A or 2B-B when Condition I is entered with no 2B-B.
inoperable. AC power source to 6.9 kV Sh td Shutdown B Board d 2A 2A-A A or 2B 2B-B.B Required R i dAActions ti ffor d declaring l i AND ------------------------------------------------
required feature(s) supported DG 2A-A or 2B-B I.1 Restore offsite circuit to 7 days by the inoperable DG or offsite inoperable. OPERABLE status.
circuit inoperable with OR concurrent inoperable p
I.2 Restore DG to OPERABLE 7 days redundant feature(s) are status. addressed in ACTIONS A, B, C, and D, as applicable.
Note requires entering Conditions and Required Actions of LCO 3.8.9 when 6.9 kV Shutdown Board 2A-A or 2B-B is de-energized.
Improved Technical Specifications Nuclear LCO 3.8.9 389 Train T i A anddTTrain i B AC AC, vital i l DC DC, AC vital, i l andd diesel generator (DG) DC electrical power y
distribution subsystems shall be OPERABLE.
APPLICABILITY: MODES 1, 2, 3, and 4.
Improved Technical Specifications Nuclear CONDITION REQUIRED ACTION COMPLETION TIME A. One or more Unit 1 AC A.1 --------------NOTE--------------
electrical power Enter applicable Conditions distribution subsystems and Required Actions of inoperable. LCO 3.8.4, "DC Sources -
Operating," for vital DC trains made inoperable by inoperable power distribution subsystems.
Restore Unit 1 AC electrical 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> power distribution subsystem(s) y ( ) to OPERABLE status.
B. One or more AC vital B.1 Restore AC vital 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> subsystems inoperable. subsystem(s) to OPERABLE status.
C. One vital DC electrical C.1 Restore vital DC electrical 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> power distribution power distribution subsystem inoperable. subsystem to OPERABLE status.
D O D. One or more Unit U it 2 AC D1 D.1 Declare D l associated i t d I Immediately di t l electrical power required feature(s) distribution subsystems inoperable.
ITS Example - Shutdown Board 2B-B De-Energized; Unit 1 in Mode 1-4 (Unit 2 in Mode 5 or 6)
Nuclear DG 2B-B DG 2A-A DG 1B-B DG 1A-A Normal Supply Normal Supply Normal Supply Normal Supply From 2C Unit Bd. From 2B Unit Bd. From 1C Unit Bd. From 1B Unit Bd.
NO NC NO NC NO NC NO NC 6.9 kV 6.9 kV 6.9 kV 6.9 kV Shutdown Shutdown Shutdown Shutdown Bd. 2B-B Bd. 2A-A Bd. 1B-B Bd. 1A-A ERCW U2 B ESF ERCW U2 A ESF ERCW U1 B ESF ERCW U1 A ESF Loads Loads Loads Loads Need LAR approved 480 V Loads 480 V Loads 480 V Loads 480 V Loads Air Return Fan 2B-B Air Return Fan 2A-A Air Return Fan 1B-B Air Return Fan 1A-A Not needed for Unit 1 CCS Pump 2A-A CCS Pump 1B-B CCS Pump 1A-A CCS Pump 2B-B ABGTS Fan A-A** EGTS Fan B-B** EGTS Fan A-A**
Aux Control Air Compressor A-A** CR AHU B-B** CR AHU A-A**
Not needed for Unit 1 125 V Vital Batt Chrgr III** 125 V Vital Batt Chrgr II** 125 V Vital Batt Chrgr I**
CCS Pump C-S**
120 V Vital Inverters 1-III, 1 III, 2 2-III**
III 120 V Vital Inverters 1-II, 1 II, 2 2-II**
II 120 V Vital Inverters 1-I, 1 I, 2 2-I**
I N t needed Not d d for f Unit U it 1, 1 CCS Pump 1B-B will satisfy B Train ABGTS Fan B-B**
Enter LCO 3.7.12 Condition A (7 days)
Aux Control Air Compressor B-B**
Need Mod completed 125 V Vital Batt Chrgr IV IV**
Enter LCO 3.8.4 Condition A (7 days) 120 V Vital Inverters 1-IV, 2-IV**
Inverters operable with power input from the 125 VDC Vital Batteries **Shared System
ITS Example - Shutdown Board 2B-B De-Energized; Unit 2 in Mode 5 or 6 Nuclear DG 2B-B DG 2A-A DG 1B-B DG 1A-A Normal Supply Normal Supply Normal Supply Normal Supply From 2C Unit Bd. From 2B Unit Bd. From 1C Unit Bd. From 1B Unit Bd.
NO NC NO NC NO NC NO NC 6.9 kV 6.9 kV 6.9 kV 6.9 kV Shutdown Shutdown Shutdown Shutdown Bd. 2B-B Bd. 2A-A Bd. 1B-B Bd. 1A-A ERCW U2 B ESF ERCW U2 A ESF ERCW U1 B ESF ERCW U1 A ESF Loads Loads Loads Loads Not needed for Unit 2 Not needed
- for Unit 2 480 V Loads 480 V Loads 480 V Loads 480 V Loads Air Return Fan 2A-A Air Return Fan 1B-B Air Return Fan 1A-A CCS Pump 2A-A CCS Pump 1B-B CCS Pump 1A-A Air Return Fan 2B-B ABGTS Fan A-A EGTS Fan B-B EGTS Fan A-A Not needed for Unit 2 Aux Control Air Compressor A-A CR AHU B-B CR AHU A-A CCS Pump 2B-B 125 V Vital Batt Chrgr III 125 V Vital Batt Chrgr II 125 V Vital Batt Chrgr I Not needed for Unit 2 120 V Vital Inverters 1-III, 1 III, 2 2-III III 120 V Vital Inverters 1-II, 1 II, 2 2-II II 120 V Vital Inverters 1-I, 1 I, 2 2-II CCS Pump C-S Not needed for Unit 2 ABGTS Fan B-B Not needed for Unit 2 Aux Control Air Compressor B-B Not needed for Unit 2 125 V Vital Batt Chrgr IV Note ### :
Not needed for Unit 2 - Mode 5: RCS loops filled and 120 V Vital Inverters 1-IV, 2-IV 2 SG water level 21% NR, or Not needed for Unit 2 ### - Mode 6: Reactor Vessel water level 23 ft above flange
Summary Nuclear 3/4 Changes to the SQN TSs are required to facilitate 6.9 kV and 480 V board maintenance and alleviate the overly restrictive CTS requirements 3/4 ITS will establish controls commensurate with the safety function of the affected equipment 3/4 Additional Actions for inoperable AC power sources (or de-energi ed boards) on the opposite unit energized nit ha have e been de developed eloped 3/4 ITS LCO 3.8.1 Actions will require declaring required features supported by the inoperable AC power source inoperable when redundant features are also inoperable, with a backstop 3/4 ITS LCO 3.8.9 Actions will require declaring the required features supported by the de-energized de energized board inoperable immediately