NL-16-2280, Vogtle Electric Generating Plant, Units 1 & 2, Updated Final Safety Analysis Report, Figure 7.6.5-1 (Sheet 1 of 2) Through Figure 8.3.1-1 (Sheet 4 of 34)
Text
REV 14 10/07 SAFETY INJECTION SYSTEM RECIRCULATION SUMP AND RHR SUCTION ISOLATION VALVES FIGURE 7.6.5-1 (SHEET 1 OF 2)
REV 14 10/07 SAFETY INJECTION SYSTEM RECIRCULATION SUMP AND RHR SUCTION ISOLATION VALVES FIGURE 7.6.5-1 (SHEET 2 OF 2)
VEGP-FSAR-7 REV 17 4/12 TABLE 7.7.1-1 (SHEET 1 OF 2)
PLANT CONTROL SYSTEM INTERLOCKS
Designation Derivation Function
C-1 1/2 neutron flux (intermediate Blocks control rod range) above setpoint withdrawal C-2 1/4 neutron flux (power range)
Blocks control rod above setpoint withdrawal C-3 2/4 overtemperature T above Blocks control rod setpoint withdrawal Actuates turbine runback via load reference C-4 2/4 overpower T above Blocks control rod setpoint withdrawal Actuates turbine runback via load reference C-5 1/1 turbine impulse chamber Indication only pressure below setpoint
VEGP-FSAR-7 REV 17 4/12 TABLE 7.7.1-1 (SHEET 2 OF 2)
Designation Derivation Function
C-7 1/1 time derivative (absolute Makes steam dump value) of turbine impulse valves available for chamber pressure (decrease either tripping or only) above setpoint modulation C-9 Any condenser pressure above Blocks steam dump to setpoint or no circulating condenser water pumps running C-11 Not used.
Not used. C-16 Reduce limit in coolant Stops automatic temperature above normal turbine loading until setpoint condition clears C-20 (a) Two-of-two turbine Arms AMSAC; below impulse chamber pressure setpoint blocks AMSAC above setpoint (generated in AMSAC; see section 7.7) P-4 Reactor trip Blocks steam dump control via load T av g controller Makes steam dump valves available for either tripping or modulation Absence of P-4 Blocks steam dump control via plant trip T av g controller
- a. Not part of control system (non-Class 1E).
REV 13 4/06 SIMPLIFIED BLOCK DIAGRAM OF REACTOR CONTROL SYSTEM FIGURE 7.7.1-1
REV 13 4/06 ROD DEVIATION COMPARATOR FIGURE 7.7.1-3
REV 13 4/06 BLOCK DIAGRAM OF PRESSURIZER PRESSURE CONTROL SYSTEM FIGURE 7.7.1-4
REV 13 4/06 BLOCK DIAGRAM OF PRESSURIZER LEVEL CONTROL SYSTEM FIGURE 7.7.1-5
REV 13 4/06 BLOCK DIAGRAM OF STEAM DUMP CONTROL SYSTEM FIGURE 7.7.1-8
REV 13 4/06 BASIC FLUX-MAPPING SYSTEM FIGURE 7.7.1-9
REV 13 4/06 ACTUATION LOGIC SYSTEM ARCHITECTURE FIGURE 7.7.1-10
REV 13 4/06 SIMPLIFIED BLOCK DIAGRAM ROD CONTROL SYSTEM FIGURE 7.7.2-1
REV 13 4/06 CONTROL BANK D PARTIAL SIMPLIFIED SCHEMATIC DIAGRAM POWER CABINETS 1BD AND 2BD FIGURE 7.7.2-2
VEGP-FSAR-8
8.1-1 REV 14 10/07 8.0 ELECTRIC POWER
8.1 INTRODUCTION
8.1.1 UTILITY GRID DESCRIPTION Southern Nuclear Operating Company (SNC) is a member of Southern Company's grid system, whose other members are Alabama Power Com pany, Georgia Power Company, Gulf Power Company, Mississippi Power Company, Sav annah Electric and Power Company, and the Southern Electric Generating Company. The S outhern Company is interconnected with Duke
Power Company, Florida Peninsula Systems, Middle South Utilities, South Carolina Electric and
Gas Company, and the Tennessee Valley Authority.
Southern Company's grid system consists of interconnected hydro plants, fossil-fueled plants, and nuclear plants supplying electric energy
over a transmission system consisting of various voltages up to 500 kV, as shown on drawing AX6DD402. The figure includes the planned transmission lines for VEGP. 8.1.2 ONSITE POWER SYSTEM DESCRIPTION The plant is supplied with ac power from a 230-kV switchyard. The Unit 1 generator is connected to the 230-kV switchyard and the Unit 2 generator is connected to the 500-kV
switchyard via step-up transformers. Two 230-to 500-kV autotransformers are provided for the
interconnection of the two switchyards. The 230-kV switchyard supplies power through two
230/13.8/4.16-kV reserve auxiliary transformers per unit (preferred power source) to the engineered safety features (ESF) buses and the balance of plant (BOP) buses. There is also a "swing" 13.8/4.16-kV, 10/12.5 MVA standby auxiliary transformer (SAT) which may be manually
connected to supply power to the ESF buses and to a portion of the BOP loads. The "swing" terminology when used to describe the SAT means that the SAT alignment to the onsite
electrical distribution system is selected, with the use of administrative controls and key
interlocked disconnect switches, to supply power to any one of the safety-related buses. The
standby power source for each ESF bus is its associated emergency diesel generator set. The
preferred power source of each unit BOP load is from the 25-kV generator buses through two
25/13.8/4.16-kV unit auxiliary transformers per unit.
The Class 1E ac power system is divided into two independent divisions to provide ac power to the two divisions of ESF loads. The onsite power systems are shown in drawings 1X3D-AA-A01A, 2X3D-AA-A01A, AX3D-AA-A01A, and AX3D-AA-A03A.
Four independent 125-V dc systems supply power to the four independent reactor protection channels and both independent Class 1E ac power systems. 8.1.3 SAFETY-RELATED LOADS Safety loads are defined as those systems and devices that require electric power in order to perform their safety functions. The ac safety loads are shown in drawings 1X3D-AA-K02A, 2X3D-AA-K02A, 1X3D-AA-K02B, and 2X3D-AA-K02B. Tables 8.3.2-1, 8.3.2-2, 8.3.2-3, and 8.3.2-4 list the loads on the Class 1E 125-V dc batteries. Power supplies for the reactor
protection system have sufficient stored energy to remain available through any anticipated VEGP-FSAR-8
8.1-2 REV 14 10/07 switching transients. The power supplies are shown on drawings 1X3D-AA-G02A, 1X3D-AA-G02C, and 1X3D-AA-G01B. 8.1.4 DESIGN BASES 8.1.4.1 Offsite Power System A. Electrical power from the power grid to the plant site is supplied by two physically independent circuits designed and located to minimize the likelihood of simultaneous failure. B. Based on the grid analysis, two physically independent reserve auxiliary transformers are provided to supply the onsite electrical distribution system.
There is also a physically independent st andby auxiliary transformer to supply power to the onsite electrical distribution system. C. The loss of one of the nuclear units at VEGP or the most critical unit on the grid will not result in the loss of offsite power to the Class 1E buses. D. The switchyard is designed with duplicate and redundant systems; i.e., two independent battery systems, two trip coils per breaker, and protective relay
schemes. 8.1.4.2 Onsite Power System A. The onsite power system includes a separate and independent Class 1E electric power system for each unit [General Design Criterion (GDC) 17]. B. The onsite Class 1E ac electric power systems for each unit are divided into two independent load groups referred to as trains, each with its own power supply, buses, transformers, loads, and associated 125-V dc control power. Each train is
independently capable of maintaining one unit in a safe shutdown condition (GDC 17). C. One independent diesel generator is provided for each Class 1E ac train in each unit. The diesel generator unit provides power to the appropriate ventilation equipment to maintain an acceptable environment within the diesel generator buildings.
The diesel generator unit is capable of starting, accelerating, being loaded, and carrying the design load described in paragraph 8.3.1.1.3. The unit energizes its
cooling equipment within an acceptable time.
A discussion on conformance to Regulatory Guide 1.9 concerning frequency and voltage limits and basis of the continuous rating is contained in section 1.9.
Mechanical and electric systems are designed so that a single failure affects the operation of only a single diesel generator.
Design conditions such as vibration, torsional vibration, and overspeed are considered in accordance with the requirements of Institute of Electrical and
Electronics Engineers (IEEE) Standard 387.
VEGP-FSAR-8
8.1-3 REV 14 10/07 Each diesel governor can operate in the droop mode, and the voltage regulator
can operate in the paralleled mode during diesel generator testing. If an
underfrequency condition occurs while the diesel generator is paralleled with the
preferred (offsite) power supply, the diesel generator breaker is tripped and the
governor and voltage regulator are automatically restored to the isochronous and
nonparalleled modes, respectively.
Each diesel generator is provided with control systems permitting automatic and manual control. The automatic start signal is functional except when the diesel
generator is in the maintenance mode. Also, the automatic start signal will not
override the rampup time when the governor is in the slow start mode. The
details of the affects during the slow start mode are described in paragraph
8.3.1.1.3.k. Provision is made for controlling each diesel generator from the
control room or from the diesel generator room. Paragraph 8.3.1.1.3 provides
further description of the control systems.
Voltage, current, frequency, var, and watt metering is provided in the control room to permit assessment of the operating condition of each diesel generator.
Surveillance instrumentation is provided in accordance with IEEE 387, as described in subsections 9.5.4 through 9.5.8.
Tests are conducted on each diesel generator unit in accordance with IEEE 387, as listed in paragraph 8.3.1.1.3. D. No provisions are made for automatic transfer of trains between redundant power sources. E. No portion (ac or dc) of the onsite standby power systems is shared between units (GDC 5). F. The Class 1E electric systems are designed to satisfy the single failure criterion (GDC 17). G. For each of the four protection channels, one independent 125-V dc and at least one 120-V vital ac power source are provided. Batteries are sized for 165 min of
operation for LOSP/LOCA and 240 min for SBO without the support of battery
chargers. H. Separate non-Class 1E dc systems are provided for non-Class 1E controls and dc motors. I. Raceways are not shared by Class 1E and non-Class 1E cables. J. Special identification criteria are applied for Class 1E equipment, including cabling and raceways. Refer to paragraph 8.3.1.3. K. Separation criteria are applied which establish requirements for preserving the independence of redundant Class 1E electric systems. Refer to paragraph 8.3.1.4.1. L. Class 1E equipment is designed with the capability of being tested periodically (GDC 18). 8.1.4.3 Design Criteria, Regulatory Guides, and IEEE Standards Compliance to GDC 17, 18, and 50 is discussed in section 3.1 and paragraphs 8.3.1.2, 8.3.2.2, and 8.3.1.1.12. The design of the offsite power and onsite Class 1E electric systems generally VEGP-FSAR-8
8.1-4 REV 14 10/07 conforms with the regulatory guides and standards listed below as clarified in section 1.9. Refer
to table 8.1-1 for acceptance criteria and guidelines and their applicability to chapter 8. A. General Design Criteria 1. GDC 2, Design Bases for Protection Against Natural Phenomena. 2. GDC 4, Environmental and Missile Design Bases.
- 3. GDC 5, Sharing of Structures, Systems, and Components.
- 4. GDC 17, Electric Power Systems.
- 5. GDC 18, Inspection and Testing of Electric Power Systems.
- 6. GDC 50, Containment Design Basis.
See section 3.1 for a discussion of conformance with each of the general design criteria. B. Nuclear Regulatory Commission (NRC) Regulatory Guides See section 1.9 for a discussion of conformance to the regulatory guides listed
below. 1. Regulatory Guide 1.6, Independence Between Redundant Standby (Onsite) Power Sources and Between Their Distribution Systems. 2. Regulatory Guide 1.9, Selection, Design, and Qualification of Units Used as Standby (Onsite) Electric Power Systems at Nuclear Power Plants. 3. Regulatory Guide 1.22, Periodic Testing of Protection System Actuation Functions. 4. Regulatory Guide 1.29, Seismic Design Classification.
- 5. Regulatory Guide 1.30, Quality Assurance Requirements for the Installation, Inspection, and Testing of Instrumentation and Electric Equipment. 6. Regulatory Guide 1.32, Criteria for Safety- Related Electric Power Systems for Nuclear Power Plants. 7. Regulatory Guide 1.40, Qualification Tests of Continuous-Duty Motors Installed Inside the Containment of Water-Cooled Nuclear Power Plants. 8. Regulatory Guide 1.41, Preoperational Testing of Redundant Onsite Electrical Power Systems to Verify Proper Load Group Assignments. 9. Regulatory Guide 1.47, Bypassed and Inoperable Status Indication for Nuclear Power Plant Safety Systems. 10. Regulatory Guide 1.53, Application of the Single-Failure Criterion to Nuclear Power Plant Protection Systems. 11. Regulatory Guide 1.62, Manual Initiation of Protective Actions. 12. Regulatory Guide 1.63, Electric Penetration Assemblies in Containment Structures for Light-Water-Cooled Nuclear Power Plants. 13. Regulatory Guide 1.68, Preoperational and Initial Startup Test Programs for Water-Cooled Power Reactors.
VEGP-FSAR-8
8.1-5 REV 14 10/07 14. Regulatory Guide 1.73, Qualification Tests of Electric Valve Operators Installed Inside the Containment of Nuclear Power Plants. 15. Regulatory Guide 1.75, Physical Independence of Electric Systems. 16. Regulatory Guide 1.81, Shared Emergency and Shutdown Electric Systems for Multi-Unit Nuclear Power Plants. 17. Regulatory Guide 1.89, Qualification of Class 1E Equipment for Nuclear Power Plants. 18. Regulatory Guide 1.93, Availability of Electric Power Sources.
- 19. Regulatory Guide 1.100, Seismic Qualification of Electrical Equipment for Nuclear Power Plants. 20. Regulatory Guide 1.106, Thermal Overload Protection for Electric Motors on Motor-Operated Valves. 21. Regulatory Guide 1.108, Periodic Testing of Diesel Generators Used as Onsite Electric Power Systems at Nuclear Power Plants. 22. Regulatory Guide 1.118, Periodic Testing of Electric Power and Protection Systems. 23. Regulatory Guide 1.128, Installation Design and Installation of Large Lead Storage Batteries for Nuclear Power Plants. 24. Regulatory Guide 1.129, Maintenance, Testing, and Replacement of Large Lead Storage Batteries for Nuclear Power Plants. 25. Regulatory Guide 1.131, Qualification Tests of Electric Cables, Field Splices, and Connections for Light-Water-Cooled Nuclear Power Plants. C. IEEE Standards The onsite power system is generally designed in accordance with IEEE Standards 279, 308, 317, 323, 334, 336, 338, 344, 379, 382, 383, 384, 387, 450, and 484. 1. IEEE 279-1971, Criteria for Protection Systems for Nuclear Power Generating Stations. Refer to Regulatory Guide 1.22. 2. IEEE 308-1974, Criteria for Class 1E Power Systems for Nuclear Power Generating Stations. Refer to Regulatory Guide 1.32. 3. IEEE 317-1976, Electrical Penetration Assemblies in Containment Structures for Nuclear Power Generating Stations. Refer to Regulatory Guide 1.63. 4. IEEE 323-1974, Qualifying Class 1E Equipment for Nuclear Power Generating Stations. Refer to Regulatory Guide 1.89. 5. IEEE 334-1974, Type Tests of Continuous Duty Class IE Motors for Nuclear Power Generating Stations. Refer to Regulatory Guide 1.40. 6. IEEE 336-1971, Installation, Inspection, and Testing Requirements for Instrumentation and Electric Equipment During the Construction of
Nuclear Power Generating Stations. Refer to Regulatory Guide 1.30. 7. IEEE 338-1977, Criteria for the Periodic Testing of Nuclear Power Generating Station Class 1E Power and Protection Systems. For VEGP-FSAR-8
8.1-6 REV 14 10/07 application of this standard to various systems, refer to paragraph 7.1.2.7
and to Regulatory Guide 1.118. 8. IEEE 344-1975, Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations. Seismic qualification of Class 1E electric
equipment and the extent of compliance with IEEE 344-1975 are
discussed in section 3.10. Also refer to Regulatory Guide 1.100. 9. IEEE 379-1972, Application of the Single Failure Criterion to Nuclear Power Generating Station Class 1E Systems. Refer to Regulatory
Guide 1.53. 10. IEEE 382-1972, Type Test of Class 1 Electric Valve Operators for Nuclear Power Generating Stations. Refer to Regulatory Guide 1.73. 11. IEEE 383-1974, Type Test of Class 1E Electric Cables, Field Splices, and Connections for Nuclear Power Generating Stations. Refer to Regulatory
Guide 1.131. 12. IEEE 384-1981, Criteria for Independence of Class 1E Equipment and Circuits. Refer to Regulatory Guide 1.75. 13. IEEE 387-1977, Criteria for Diesel-Generator Units Applied as Standby Power Supplies for Nuclear Power Generating Stations. Conformance
with the design criteria of IEEE 387-1977 is discussed in paragraph
8.3.1.1.3, which addresses the details of the standby power supply. Also
refer to Regulatory Guide 1.9. 14. IEEE 450-1975, Maintenance, Testing, and Replacement of Large Lead Storage Batteries for Generating Stations and Substations. Refer to
Regulatory Guide 1.129. The safety-related batteries will be tested
periodically in accordance with the Technical Specifications and the
version of IEEE 450 as described in the Bases for the Technical
Specifications. 15. IEEE 484-1975, Installation Design and Installation of Large Lead Storage Batteries for Generating Stations and Substations. Refer to
Regulatory Guide 1.128. 16. IEEE 628-1987, Standard Criteria for the Design, Installation, and Qualification of Raceway Systems for Class 1E Circuits for Nuclear
Power Generating Stations.
VEGP-FSAR-8 REV 14 10/07 TABLE 8.1-1 (SHEET 1 OF 3)
ACCEPTANCE CRITERIA AND GUIDELINES FOR ELECTRIC POWER SYSTEMS Applicability (FSAR(a) Criteria Title Section/Subsection) Remarks 8.2 8.3.1 8.3.2 1. GDC Appendix A to10 Code of Federal Regulations (CFR) 50
- a. GDC 2 Design Bases for Protection Against Natural Phenomena A A b. GDC 4 Environmental and Missile Design Bases A A c. GDC 5 Sharing of Structures, Systems, and Components A A A d. GDC 17 Electric Power Systems A A A e. GDC 18 Inspection and Testing of Electrical Power Systems A A A f. GDC 50 Containment Design Bases A A 2. Regulatory Guide (RG)
- a. RG 1.6 Independence Between Redundant Standby (Onsite) Power Sources and Between Their Distribution Systems G G b. RG 1.9 Selection, Design, and Qualification of Diesel- Generator Units Used as Standby (Onsite)
Electric Power Systems at Nuclear Power
Plants G c. RG 1.32 Use of IEEE Standard 308, Criteria for Class 1E Power Systems for Nuclear Power Generating Stations G G G d. RG 1.47 Bypassed and Inoperable Status Indication for Nuclear Power Plant Safety Systems G G G VEGP-FSAR-8 REV 14 10/07 TABLE 8.1-1 (SHEET 2 of 3)
Criteria Title Applicability (FSAR(a) Section/Subsection)
Remarks 8.2 8.3.1 8.3.2 e. RG 1.63 Electric Penetration Assemblies in Containment Structures for Light-Water-Cooled Nuclear Power Plants G G f. RG 1.75 Physical Independence of Electric Systems G G g. RG 1.81 Shared Emergency and Shutdown Electric Systems for Multi-Unit Nuclear Power
Plants G G G h. RG 1.106 Thermal Overload Protection for Electric Motors on Motor-Operated Valves G G i. RG 1.108 Periodic Testing of Diesel Generators Used as Onsite Power Systems at Nuclear
Power Plants G j. RG 1.118 Periodic Testing of Electric Power and Protection Systems G G k. RG 1.128 Installation Design and Installation of Large Lead Storage Batteries for Nuclear Power Plant G l. RG 1.129 Maintenance, Testing, and Replacement of Large Lead Storage Batteries for Nuclear Power Plants G 3. Branch Technical Position (BTP)
- a. BTP ICSB 4 Requirements on Motor-Operated Valves
in the ECCS Accumulator Lines G See also FSAR subsection 7.6.4 G b. BTP ICSB 8 (PSB)
Use of Diesel-Generator Sets for Peaking
- c. BTP ICSB 11 (PSB) Stability of Offsite Power Systems G VEGP-FSAR-8 REV 14 10/07 TABLE 8.1-1 (SHEET 3 of 3)
Applicability (FSAR(a) Criteria Title Section/Subsection) Remarks 8.2 8.3.1 8.3.2 d. BTP ICSB 18 (PSB) Application of the Single Failure Criterion to Manually-Controlled Electrically-Operated Valves G e. BTP ICSB 21 Guidance for Application of RG 1.47 G G G See also FSAR section 7.5 f. BTP PSB-1 Adequacy of Station Electric Distribution System Voltages G h. BTP PSB-2 Criteria for Alarms and Indications Associated with Diesel-Generator Unit Bypassed and Inoperable Status G NUREG Reports a. NUREG/CR 0660 Enhancement of Onsite Diesel Generator Reliability G
- a. A denotes acceptance criteria. G denotes guidance.
VEGP-FSAR-8
8.2-1 REV 17 4/12 8.2 OFFSITE POWER SYSTEM 8.2.1 SYSTEM DESCRIPTION The Southern Company transmission system supplie s the offsite ac energy for operating the safety-related buses as well as startup and shutdown of Units 1 and 2.
Each unit represents about 6 percent of the total installed capacity of the Georgia Power Company system in 1990 and about 3.4 percent of the total installed capacity of the Southern
Company system in 1990.
Unit 1 is connected to the 230-kV switchyard through a step-up transformer, and Unit 2 is connected to the 500-kV switchyard through a step-up transformer. Two 500/230-kV
autotransformers connect the two transmission substations together. The offsite sources are
connected via the switchyard to the 230-kV and 500-kV transmission system. 8.2.1.1 Offsite Sources Drawing AX6DD402 shows the Southern Com pany transmission system plan for 1990.
Construction of the 230-kV and 500-kV lines is summarized in table 8.2.1-1. The transmission lines are not considered to have any unusual features, and the occasional crossings of
transmission lines as listed in table 8.2.1-1 are normal design practice for the Georgia Power
Company system.
The 230-kV and 500-kV transmission systems are des igned to deliver power to the various portions of the Georgia Power Company servic e area safely, efficiently, and dependably. As a result, the system offers a very dependable power source for the required offsite loads and is the preferred power source for the safety-related loads of the plant.
An additional "swing" preferred offsite power sour ce, the standby auxiliary transformer (SAT), is also available for plant loads in response to emergency conditions or for use during reserve auxiliary transformer (RAT) maintenance. The SAT receives power from the Georgia Power Company Plant Wilson switchyard (see drawing AX3D-AA-A03A). Plant Wilson is a six-unit
combustion turbine electric generating facility located approximately 1 mile east of the Vogtle
plant site. The SAT is supplied power through a direct buried cable from either the Southern
Company 230-kV grid or Plant Wilson's onsite combustion turbine electrical generation, both
methods via the Plant Wilson switchyard 13.8-kV power system.
There are five 230-kV lines, one of which is the connection to the Plant Wilson switchyard, and two 230-kV and 500-kV autotransformers that connect the 230-kV and 500-kV switchyards.
These transmission elements at the 230-kV bus comprise the power sources to the 230-kV
switchyard. The lines approach the plant site on five rights-of-way, from the north-west and
south. System load studies indicate that this arrangement has the capacity and capability to
supply the power necessary for the safety loads of one unit while placing the other unit in cold
shutdown.
The transmission line structures of both the 230-kV and 500-kV systems are designed to withstand standard light and medium loading conditions as specified in National Institute of
Standards and Technology Handbook No. 8 (ANSI, C2.2-1960, National Electric Safety Code).
The transmission line structures for the rerouted portion of 500-kV West McIntosh transmission
line near the 500-kV switchyard are designed to withstand medium zone loading conditions as VEGP-FSAR-8
8.2-2 REV 17 4/12 well as 100 mph extreme wind as specified by the 2007 National Electric Safety Code (IEEE C2-2007). 8.2.1.2 Switchyard The 230-kV and 500-kV switchyards are arranged as shown in drawings AX3D-AA-L50A and AX3DL060. The 230-kV breaker-and-a-half arrangement is used to incorporate the redundancy
offered by having two energized buses with three breakers to service each pair of connections.
The 500-kV ring bus arrangement allows two breakers to service each terminal connection.
The switchhouse, located in the switchyard, contains two independent 125-V batteries, the primary and secondary relaying for the transmission lines, and the breaker failure relaying. It
also contains the 480-V metal-clad switchgear and motor control centers for the substation.
Two trip coils are provided in each 230-kV and 500-kV circuit breaker for independent tripping from the primary and secondary relaying systems.
Redundant closing coils are not provided in each 230-kV circuit breaker. However, the 125-V dc supplies are arranged to ensure that at
least one offsite source is available upon the loss of either substation battery. Tables 8.2.1-2
and 8.2.1-3 respectively show the 230-kV and 500-kV circuit breaker control circuits supplied by
each battery.
Each of the offsite sources from the 230-kV switchyard can be energized through either or both
of the two switchyard circuit breakers. The high voltage switchyard raceway network consists of
a system of concrete trenches with concrete lids. Control cables to the four circuit breakers are
routed through the trenches in such a way that lengthy trench sections do not include circuits to
all four offsite source breakers. Control cables to the plant control room for these breakers are
routed outdoors in conduit within a reinforced concrete duct run and within the plant in cable
tray. These cables are arranged within these raceways in such a manner that no two breakers
from different offsite sources are in a common raceway. Areas in which circuits to all four
breakers are common in this duct run are limited to the three pull boxes. Areas in which circuits
to all four breakers are routed in a common trench are limited to some areas of the switch house
interior and a small area of the trench adjacent to the switch house.
In these areas, the trench is protected by location or adjacent structure (i.e., switch house), and additional separation is not practical. All cable is fire retardant (in accordance with IEEE 383-
1974), and no oil containment equipment is located in the vicinity of the cable trench.
Two feeders emerge from the 230-kV substation to supply power to the RATs for both Units 1 and 2. (The arrangement is shown in drawings 1X3D-AA-A01A and 2X3D-AA-A01A.) Offsite source No. 1 supplies Unit 1 RAT 1NXRA and Unit 2 RAT 2NXRB. Offsite source No. 2 supplies Unit 1 reserve auxiliary transformer 1NXRB and Unit 2 RAT 2NXRA. These two offsite sources are separated physically as they leave the 230-kV substation and are arranged so that
no one event such as a falling line, tower, or other structure will damage both lines.
The 13.8-kV power circuit to the SAT is above grade only at the Plant Wilson switchyard connection point and in the Vogtle low voltage switchyard at the 13.8-kV switchgear circuit
breaker and at the SAT. Between these two points, the power circuit is either direct buried or
pulled in conduit through a concrete encased electrical duct run. The 13.8-kV power circuit is
therefore physically separated from the other offs ite power source lines. No one event, such as a falling line, tower, or other structure will damage the 13.8-kV power circuit and one of the 230-
kV power feeders. The 13.8-kV circuit breaker has a single trip coil which, along with the
protective relaying, is supplied 125-V-dc power from the turbine building batteries.
VEGP-FSAR-8
8.2-3 REV 17 4/12 The secondary windings of the RATs are connected to the various groups of metal-clad switchgear by Calvert cable busses. The Calvert cable busses from transformers 1NXRB and 2NXRA are carried in underground trenches from the transformers to the turbine building wall.
The other Calvert cable busses are run overhead to the turbine building.
The secondary winding of the SAT is connected to the various groups of metal-clad switchgear by a 4.16-kV switchgear circuit breaker, Husky cable bus, and cable bus disconnect switches.
The 4.16-kV circuit breaker has a single trip coil which, along with the protective relaying, is
supplied 125-V-dc power from the turbine building batteries. The Husky cable bus from the SAT
switchgear runs overhead to the vicinity of each RAT. At that point, the Husky cable bus is
connected to a switch that may be closed to connect the SAT to the Calvert cable bus between
the RAT and the Class 1E switchgear. Another switch in the Calvert cable bus between the
Class 1E switchgear and the RAT is opened before the SAT cable bus switch is closed. The
two cable bus switches allow the Class 1E switchgear to be connected to either a RAT or the
SAT. The manual cable bus switches are key interlocked to prevent having both the RAT and
the SAT connected to the same Class 1E bus. The switching arrangement is shown on drawings 1X3D-AA-A01A, 2X3D-AA-A01A, and AX3D-AA-A03A.
The Calvert cable busses enter the turbine building and proceed to the non-Class 1E metal-clad switchgear installed in the turbine building. The Calvert cable busses continue through the
cable tunnel between the turbine building and the control building to the Class 1E metal-clad
switchgear busses located in the control building. As these busses traverse the buildings, adequate spacing and arrangement to the extent practical are provided to minimize the chances
that both offsite sources will be eliminated by one occurrence.
8.2.2 ANALYSIS 8.2.2.1 Loss of VEGP Unit 1 or 2 or the Largest Unit A study simulating 1990 peak conditions has been made to determine the effect of the loss of either VEGP Unit 1 or 2 on the Georgia Powe r Company transmission system and its ability to
maintain continuity of service to the loads. This study reveals that the transmission system is
adequate to maintain continuity of service to the load areas and the offsite power to the safety-
related loads at the plant site.
A study simulating 1990 peak conditions has been made to determine the effect of the loss of both Units 1 and 2 and the ability of the offsite source to supply emergency and safety-related
loads at VEGP. It was found that the offsite transmission is adequate. The voltage at the
VEGP 230-kV bus is above 100 percent under any normal planning criteria.
The largest unit of the Georgia Power Company sy stem is VEGP Unit 1 or Unit 2 and loss of these units as explained above does not result in the loss of the offsite power to the safety-related buses at the plant site. The loss of the next largest unit (Bowen No. 3 or No. 4) likewise
does not result in the loss of offsite power to the safety-related buses at the plant site. 8.2.2.2 VEGP Voltage Operating Range The 230-kV bus voltage will not be less than 230 kV (100 percent) or greater than 242 kV (105 percent) for all system loading conditions and under severe contingencies such as loss of any
large generating plant, including VEGP itself (Unit 1 and Unit 2 shutdown and/or loss-of-coolant
accident loads), or loss of any single transmission element. (See GPC letters SL-2110 dated VEGP-FSAR-8
8.2-4 REV 17 4/12 March 9, 1987, and GN-1525 dated December 13, 1988, for a detailed description of the effect
of switchyard voltages on in-plant loads.) 8.2.2.3 VEGP Transient Stability Based on the offsite power system described in subsection 8.2.1, a transient stability study simulating 1990 summer peak and spring valley loading conditions has been made to determine
the transmission line, bus arrangement, and/or special equipment requirements to ensure stable
operation of the grid for VEGP Units 1 and 2.
These extreme system loading conditions ensure
that the stability performances of VEGP are analyzed under all reactive loading conditions or
power factor conditions. The following contingencies are simulated for which the grid is
required to remain stable: A. Three-phase fault with breaker failure anywhere in the system. B. Sudden loss of any large generating plant.
C. Sudden loss of all lines on any common right-of-way.
D. Sudden loss of any large aggregation of load or load center anywhere in the system.
Of these contingencies, it was found that a three-phase fault with breaker failure results in the largest transient swing. For this severe contingency, grid stability is maintained. Specific
stability performance issues of VEGP are discussed below. A. Frequency Decay Rate The maximum frequency decay rate possible from theoretical considerations for
the 230-kV and 500-kV systems is 5 Hz/s and 5.4 Hz/s, respectively. These
frequency decay rates are the theoretical maximums that occur with the
simultaneous tripping of many 500-kV, 230-kV and 115-kV lines such that a large
island is formed in which all generation, other than one VEGP unit, is off line.
The probability for such a scenario is immeasurably small. If for the improbable
scenario just described, one additional major generating unit is in operation, the
expected frequency decay rate is reduced to approximately 2 Hz/s for VEGP.
However, the probability for this system condition is also immeasurably small. B. Load Dispatch System Automatic load dispatch is not used at the plant; therefore, the load dispatch
system will not interfere with safety actions required of the reactor protection system.
In addition to the transient stability study described above, the stability of the grid is also
assessed whenever a major electrical element, such as a bulk power transmission line or a
500/230-kV autotransformer in the vicinity of VEGP, is temporarily out of service. The assessment, although not specifically required, is to verify that preferred power will be available in the event another major transmission system element is lost while the offsite power system is
in this temporary configuration. This assessment is based upon the guidelines of the
Southeastern Electric Reliability Council (SERC) planning criteria to ensure that preferred power
will be available. The assessment consider s the actual and projected system power requirements, actual transmission elements in service, intercompany transactions, and other
information, as applicable. If the grid is found to be potentially unstable, then appropriate
actions will be taken in a timely manner.
VEGP-FSAR-8
8.2-5 REV 17 4/12 8.2.2.4 Conformance to Criteria The preferred power sources; i.e., the offsite sources, are not Class 1E and are not
manufactured and purchased under a quality assurance program as described in chapter 17.
However, all material is the highest grade of commercial equipment manufactured to the
industrial standards listed below. The design is similar to the Class 1E systems and subjected
to the same type of reviews, checks, and calculation methods. As a result, the design is
considered to meet General Design Criterion 1 of 10 CFR 50, Appendix A.
To comply with General Design Criterion 3, t he offsite power systems have spatial separation and/or totally enclosed raceways over their entire length. Fire protection and detection are provided as discussed in subsection 9.5.1.
To comply with General Design Criterion 4, two of the offsite power sources are either direct buried or routed in duct banks and trenches below grade in exterior areas, and the other offsite
source is routed overhead in cable trays.
Thus, all features of the offsite (preferred) power supply are designed to provide maximum practical reliability and redundancy in servicing the station safety load groups. Compliance with
General Design Criterion 17, Electric Power System, is demonstrated by supplying the
switchyard with ac power by two or more physically independent 230-kV circuits. Furthermore, the offsite power sources to the engineered safety features buses are either brought in by two
physically independent circuits from the switchya rd through the reserve auxiliary transformers (RAT) or another method of providing offsite power to either one of the engineered safety
features buses is available with a 13.8-kV underground circuit emanating from the Georgia Power Company Plant Wilson switchyard th rough the standby auxiliary transformer (SAT)
located in the Vogtle low voltage switchyard. Physical separation, the breaker-and-a-half
switching configuration, redundant switchyard protection systems, and the transmission system are designed on load flow and stability studies to minimize simultaneous failure of all offsite
power sources.
Compliance with General Design Criterion 18 is achieved by designing testability and inspection capability into the system and then implement ing a comprehensive testing and surveillance program. The inspection and testing of the 230-kV and 500-kV breakers or disconnects, and
the transmission line protective relaying can be done on a routine basis, without removing either
the RATs, the SAT, or most transmission lines from service. 8.2.2.5 Standards and Guides In addition to the Nuclear Regulatory Commission General Design Criteria, the industry guides and standards listed below, and references thereto, are used in the design and procurement of
the offsite power system. A. Institute of Electrical and Electronic Engineers (IEEE) Standard 450-1975, IEEE Recommended Practice for Maintenance, Testing, and Replacement of Large
Stationary Type Power Plant and Substation Lead Storage Batteries. The
safety-related batteries will be tested periodically in accordance with the
Technical Specifications and the version of IEEE 450 as described in the Bases
for the Technical Specifications. B. American National Standards Institute (ANSI) C37.010-1972, Application Guide for ac High Voltage Circuit Breakers.
VEGP-FSAR-8
8.2-6 REV 17 4/12 C. ANSI C37.90-1971, IEEE Standard for Relays and Relay Systems Associated with Electric Power Apparatus. D. ANSI C57.12.00-1973, General Requirements for Distribution, Power, Regulating Transformers, and Shunt Reactors. E. Insulated Cable Engineers Association (ICEA) S-19-81 (5th Edition), Rubber-Insulated Wire and Cable for the Transmission and Distribution of Electrical
Energy, Revision 5, 1976. F. ICEA S-66-524, Cross-Linked-Thermosetting-Polyethylene-Insulated Wire and Cable for the Transmission and Distribution of Electrical Energy, Revision 5, 1976. G. ICEA S-68-516, Ethylene-Propylene-Rubber-Insulated Wire and Cable for the Transmission and Distribution of Electrical Energy, Revision 1, 1977. H. IEEE Standard 383, Standard for Type Test of Class 1E Electric Cables, Field Splices, and Connections for Nuclear Power Generating Stations, February 28, 1974. I. American Society of Testing Materials (ASTM) B8, Standard Specification for Concentric-Lay-Stranded Copper Conductors, Hard, Medium-Hard, or Soft, 1971.
J. ASTM-B33, Standard Specification for Tinned Annealed Copper Wire for Electrical Purposes, 1971. K. ASTM-B189, Specification for Lead-Coated and Lead-Alloy-Coated Soft Copper Wire for Electrical Purposes, 1981.
VEGP-FSAR-8 REV 14 10/07 TABLE 8.2.1-2 THE ASSIGNMENT OF 230-kV CIRCUIT BREAKER SUPPLIES TO SUBSTATION BATTERIES Battery No. 1 Battery No.2 230-kV CB Line Relaying (a) Close Trip No. Line Relaying (a) Close Trip No.
161760 P X 1 S 2 161860 P X 1 S 2 161960 P 2 S X 1
161750 (b) P X 1 S 2 161850 (b) P X 1 S 2 161950 (b) P 2 S X 1 161710 P X 1 S 2 161810 P X 1 S 2 161910 P 2 S X 1
161730 S X 1 P 2 161830 S 2 P X 1 161930 S 2 P X 1
161720 P X 1 S 2 161820 P X 1 S 2 161920 P 2 S X 1
161740 P X 1 S 2 161840 P X 1 S 2 161940 P 2 S X 1
161770 S X 2 P 1 161990 P 1 S X 2
- a. P denotes primary; S denotes secondary.
- b. Future.
VEGP-FSAR-8 REV 14 10/07 TABLE 8.2.1-3 THE ASSIGNMENT OF 500-kV CIRCUIT BREAKER SUPPLIES TO SUBSTATION BATTERIES Battery No. 1 Battery No. 2 Line Line 500-kV PC B Relaying (a Close Trip No. Relaying (a) Close Trip No. 161520 P X 1 S 2 161620 P X 1 S 161660 P 2 S X 1
161540 S X 1 P 2 161640 S 2 P X 1
- a. P denotes primary; S denotes secondary.
VEGP-FSAR-8 REV 14 10/07 TABLE 8.2.2-1 46-, 69-, 115-, 230-, AND 500-kV LINE INTERRUPTIONS CAUSED BY LIGHTNING INTERRUPTIONS FOR 100 MILES FOR YEAR 1979 Type of Lines and Voltage Miles No. of Lightning Outages Outages per 100 Miles 500-kV steel towers 766.83 3.0 0.39 230-kV steel H-frame 3,289.03 23.0 0.70 and wood H-frame 115-kV wood H-frame, 5,408.72 305.00 5.64 wood SP, steel SP 69-kV wood H-frame 464.41 68.00 14.64
wood single pole 46-kV wood single pole 4,006.69 848.00 21.16 Duration of Outage 230-kV Lines Month Day Time (h) (min) (s) Austin Dr.-Klondike 230 kV (a) 07 21 1510 000 00 00 Austin Dr.-Scottdale 230 kV((a) 07 20 1629 000 00 00 Bio-Center 230 kV((a) 06 30 0520 000 00 00 Bonaire-Butler 230 kV (a) 04 09 0138 000 00 00 Boulevard-Peachtree 230 kV (a) 08 26 1646 000 00 00 Bowen-Hammond No. 1 230 kV 04 12 0720 001 15 00 Bowen-Pinson 230 kV (a) 06 30 0442 000 00 00 Branch-Klondike 230 kV(a) 08 10 0004 000 00 00 Bremen-Villa Rica 230 kV 06 02 1413 000 00 15 Dum Jon-Evans 230 kV(a) 07 18 1403 000 00 00 Dum Jon-Evans 230 kV(a) 08 01 1423 000 00 00 E. Dalton-Widows Creek 230 kV (a) 05 13 0755 000 00 00 E. Dalton-Widows Creek 230 kV (a) 07 21 0929 000 00 00 Farley-S. Bainbridge 230 kV (a) 09 01 1936 000 00 00 Gaston AL-Yates 230 kV 08 10 1305 000 00 03 McDonough-Northwest 1 230 kV (a) 04 13 0914 000 00 00 McDonough-Northwest 1 230 kV (a) 04 13 0915 000 00 00 McDonough-Northwest 1 230 kV (a) 09 28 1928 000 00 00 McDonough-Northwest 1 230 kV (a) 09 28 1935 000 00 00 McDonough-Peachtree 230 kV (a) 05 01 0006 000 00 00 McDonough-Peachtree 230 kV (a) 08 31 2000 000 00 00 Nelson-Norcross 230 kV(a) 04 13 0834 000 00 00 Nelson-Norcross 230 kV(a) 08 11 1200 000 00 00
- a. Instantaneous; time was not recorded.
VEGP-FSAR-8 REV 14 10/07 TABLE 8.2.2-2
SUMMARY
OF TRANSMISSION LINE FAILURES - 1979 Type of Failure Number Cause of Failure Number Pole 9 Lightning 1247 Line insulator 66 Trees 61 Switch 31 High winds 6 Cold weather 22 Conductors 33 Others (b) 532 Crossarm 14 Shield wire contact 13 Others (a) 146 Total failures 312 1868
Voltage Structure Number of Failure per Class Miles Failures 100 Miles of Line 500 kV 766.83 6 0.78 230 kV 3,289.03 43 1.31 115 kV 5,408.72 495 9.15 69 kV 464.41 109 23.47 46 kV 4,006.69 1527 38.11 Total 13,935.68 2180 15.64
- a. Other types of failure include conductor shorted together, foreign matter on lines, line switch failures, prearranged outages, and unknown causes.
- b. Other causes of failure include vandals, automobiles, trucks, airplanes, and unknown
causes.
VEGP-FSAR-8 REV 14 10/07 TABLE 8.3.1-1 (SHEET 1 OF 3)
DIESEL GENERATOR ANNUNCIATOR POINTS
- 3. High temperature lube oil - in 4. High temperature lube oil - out 5. Trip - high temperature lube oil 6. Low level lube oil 7. Trip - high temperature engine bearing 8. Trip - high crankcase pressure 9. Trip - vibration 10. Trip - overspeed 11. Low temperature jacket water - in 12. Low temperature jacket water - out 13. High temperature jacket water - in 14. High temperature jacket water - out 15. Trip - high temperature jacket water 16. Low pressure jacket water 17. Trip - low pressure jacket water 18. Low level jacket water
- 19. Deleted 20. Generator trouble 21. High generator bearing temperature 22. High generator control panel temperature
- 23. Deleted 24. Generator fault 25. Trip - generator differential 26. Maintenance lock out
VEGP-FSAR-8 REV 14 10/07 TABLE 8.3.1-1 (SHEET 2 OF 3)
- 27. Low pressure lube oil 28. Trip - low pressure lube oil 29. Low pressure turbo oil - right 30. Low pressure turbo oil - left 31. Trip - low pressure turbo oil
- 32. High P fuel oil filter 33. Low pressure fuel oil
- 34. High level diesel fuel oil storage tank 35. Low level diesel fuel oil storage tank 36. High/low level diesel fuel oil day tank
- 37. Low pressure control air 38. Low pressure starting air 39. High pressure starting air 40. Failed to start 41. Switch not in auto 42. Barring device engaged 43. Panel intrusion 44. High engine control panel temperature 45. Emergency start 46. Diesel generator bypassed (a) 47. High P lube oil filter 48. Low oil pressure sensor malfunction 49. Low voltage 50. Engine control in local 51. Diesel generator emergency trip not reset
- 52. Generator underfrequency 53. Diesel generator circuit breaker inoperable 54. Loss of generator dc control power 55. Loss of starting air dc control power
VEGP-FSAR-8 REV 14 10/07 TABLE 8.3.1-1 (SHEET 3 OF 3)
- 56. High level fuel injection burst protection tank 57. Diesel generator engine panel annunciator power failure (b) 58. Engine control panel power A failure 59. Engine control panel power B failure
- a. This alarm is displayed on the system status monitoring panel in the control room only.
- b. This alarm is displayed on the control room annunciator only.
VEGP-FSAR-8 REV 16 10/10 TABLE 8.3.1-2 DIESEL GENERATOR LOADING PROFILE FOR LOCA AND LOSS OF OFFSITE POWER
Inrush Running (Cumulative)(b)
Step kW kVAr kVA kW kVAr kVA 0 2384 (a) 23881 (a) 24000 (a) 0 0 0 0.5 2471 4912 5499 1041 597 1200 5.5 1795 3509 3995 1399 747 1586 10.5 2021 2802 3455 1767 921 1993 15.5 2745 3683 4593 2278 1108 2533 20.5 4414 9255 10254 3527 1672 3903 25.5 5922 10257 11844 4675 2261 5193 30.5 5275 3889 6553 4900 2571 5334 36.0(RESET)
(c) 6791 8093 10564 5716 3062 6485 For Loss of Offsite Power (No LOCA) 0 3178 (a) 31842 (a) 32000 (a) 0 0 0 0.5 2292 4828 5344 993 571 1146 5.5 0 0 0 993 571 1146 10.5 2558 2271 3421 2212 1074 2459 15.5 3376 4563 5676 2837 1306 3123 20.5 4923 9457 10662 4085 1870 4493 25.5 6453 10448 12280 5233 2458 5781 30.5 5938 4475 7435 5440 2613 6035 31.5(RESET)
(c) 7284 8147 10929 6444 (d) 3102 7152
(a) The 4160/480V SWGR transformer inrush contribution during energization. This transformer inrush is present for approximately six cycles. (b) Running load includes; running load of previous steps plus the equivalent running load of the loads which are started during that step. (c) Loads added after RESET step are connected manually and randomly up to the diesel generator capacity. (d) EDG surveillance testing per Technical Specification 3.8.1 is performed at a load 6500 kW, though the actual maximum load is < 6500 kW.
VEGP-FSAR-8 REV 14 10/07 TABLE 8.3.1-3 (SHEET 1 OF 12)
ONSITE POWER SYSTEM FAILURE MODES AND EFFECTS ANALYSIS Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks
- 1. 1AA02, control Receive and A Grounded, Switchgear trouble None; loss of train During a LOSP when building 4160-V distribute bus fault alarm in cont rol A; train B available the bus is fed from 1E switchgear, electric power room the diesel generator, train A via breakers a single ground fault will not cause a trip of train A
- 2. Breaker 05, (c) Open on loss of A Fail to open Failure to open None; loss of train This breaker preferred power to preferred power alarm in c ontrol A; train B available electrically interlocked item 1, 1E and remain open room from item 5 with item 3 and switchgear, train item 77 breakers A, normally closed Inadvertent None None; loss of train closure A; train B available
- 3. Breaker 19, (c) Close on loss of A Fail to close Alarm in control None; loss of train This breaker diesel generator offsite power room; safety A; train B available electrically interlocked 1A power to item and remain equipment failed with item 2 and 1, 1E switchgear, closed to start from item 77 breakers train A, open item 5 sequencer Inadvertent Switchgear trouble None; loss of train opening alarm in control A; train B available room 4. Diesel generator Provide onsite A Fail to start Diesel generator None; loss of train Diesel generator 1A, train A ac power upon failed to star t A; train B available started by item 5 loss of preferred alarm in control sequencer upon power room loss of preferred power or receipt of a safety injection signal Fail to run Various specific None; loss of train alarms provided A; train B available in control room and at local diesel generator control panels
VEGP-FSAR-8 TABLE 8.3.1-3 (SHEET 2 OF 12)
REV 14 10/07 Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks
- 5. Sequencer, train A Shed all loads from train A Class 1E power system upon loss of preferred power and reconnect
all required safe shutdown loads to diesel generator, item 4, via item 1 switchgear in a programmed manner A Fail to operate(d) Sequencer trouble alarm, audio and visual, in control room None; loss of train A; train B available
- 6. Breaker 10, (c) item 1, 1E 4160-V switchgear, to
item 7, 1AB15X transformer, train A, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 7. 1AB15X transformer, item 1, 4160-V switchgear, to item 9, 480-V switchgear, train A Reduce 4160 V to 480 V A Fail to operate Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 8. Breaker 01, (c) item 7 transformer to item 9, 480-V switchgear, train A, normally closed Open on load shedding and reclose on sequencer program A Fail to open None None Slightly heavier load on initial sequencer step Fail to reclose Alarm in control room; safety equipment failed to start from item 5
sequencer None; partial loss of train A; train B available
- 9. 1AB15, 1E, 480-V switchgear, auxiliary building, train A Receive and distribute electric power via breakers A Grounded, bus fault Switchgear trouble alarm in control room Partial loss of train A;
train B available System can operate with a single grounded phase
- 10. Breaker 10, (c) item 9, 480-V switchgear, to item 11 MCC, train A, normally closed Provide continuity and protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 11. 1ABD, 1E MCC, auxiliary building, train A Receive and distribute electric power via breakers A Grounded, bus fault Item 9 switchgear trouble alarm Partial loss of train A;
train B available Ground would be sensed and alarmed in control room from item 9 switchgear (see item 1 method of failure detection); system can VEGP-FSAR-8 TABLE 8.3.1-3 (SHEET 3 OF 12)
REV 14 10/07 Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks operate with a single grounded phase
- 12. Breaker 9, (c) item 9, 480-V switchgear, to item 13 MCC, train A, normally closed Provide continuity and protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 13. 1ABB, 1E MCC, auxiliary building, train A Receive and distribute electric power via breakers A Grounded, bus fault Same as 11 Same as 11 Ground would be sensed and alarmed in control room from item 9 switchgear (see item 1 method of failure detection); system can operate with a single grounded phase
- 14. Breaker 21, (c) item 1, 1E 4160-V switchgear, to item 15, 1AB05X transformer, train A, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 15. 1AB05X transformer, item 1, 4160-V switchgear, to item 17 480-V switchgear, train A Reduce 4160 V to 480 V Fail to operate Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 16. Breaker 01, (c) item 15 transformer to item 17, 480-V switchgear, train A, normally closed Open on load shedding and
reclose on sequencer program A Fail to open None None Slightly heavier load on initial sequencer step Fail to reclose Alarm in control room; safety equipment failed to start from item 5 sequencer None; partial loss of train A; train B available
- 17. 1AB05, 1E 480-V switchgear, control
building, train A Receive and distribute electric power
via breakers A Grounded, bus fault Switchgear trouble alarm in control room Same as 9 System can operate with a single grounded phase
- 18. Breaker 14, (c) item 17, 480-V switchgear, to item 19 MCC, train A, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 19. 1ABF, 1E MCC, diesel Receive and distribute A Grounded, Item 17 switchgear Same as 9 Ground would be VEGP-FSAR-8 TABLE 8.3.1-3 (SHEET 4 OF 12)
REV 14 10/07 Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks generator building, train A electric power
via breakers bus fault trouble alarm sensed and alarmed in control room from item 17 switchgear; system can operate with a single grounded phase
- 20. Breaker 5, (c) item 17, 480-V switchgear, to item 21 MCC, train A, normally closed Provide continuity and protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 21. 1ABC, 1E MCC, control building, train A Receive and distribute electric power via breakers A Grounded, bus fault Same as 19 Same as 9 Ground would be sensed and alarmed from item 17 switchgear; system can operate with a single grounded phase
- 22. Breaker 2, (c) item 17, 480-V switchgear, to item 23 MCC, train A, normally closed Provide continuity and protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 23. 1ABA, 1E MCC, control building, train A Receive and distribute electric power via breakers A Grounded, bus fault Same as 19 Same as 9 Ground would be sensed and alarmed from item 17 switchgear; system can operate with a single grounded phase
- 24. Breaker 20, (c) item 1, 1E 4160-V switchgear, to
item 25, 1AB04 transformer, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 25. 1AB04X transformer, item 1, 4160-V switchgear, to item 27, 480-V switchgear, train A Reduce 4160 V to 480 V A Fail to operate Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 26. Breaker 01, (c) item 25 transformer to item 27, 480-V switchgear, train A, normally closed Open on load shedding and reclose on sequencer program Fail to open None None Slightly heavier load on initial sequencer step Fail to reclose Alarm in control room; safety equipment failed to start from item 5 sequencer None; partial loss of train A; train B available
VEGP-FSAR-8 TABLE 8.3.1-3 (SHEET 5 OF 12)
REV 14 10/07 Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks
- 27. 1AB04, 1E 480-V switchgear, control building, train A Receive and distribute electric power via breakers Grounded, bus fault Switchgear trouble alarm in control room Same as 9 System can operate with a single grounded phase
- 28. Breaker 02, (c) item 27, 480-V switchgear, to item 29 MCC, train A, normally closed Provide continuity and protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train A; train B available
- 29. 1ABE, 1E MCC, control building, train A Receive and distribute electric power via breakers A Grounded, bus fault Item 27 switchgear trouble alarm Same as 9 Ground would be sensed and alarmed in control room from item 27 switchgear; system can operate with a single grounded phase
- 30. Breaker 22, (c) item 1, 1E 4160-V switchgear, to item 31, 1NB01X non-1E transformer, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; loss of train A oriented non-1E power; train B oriented non-1E power available The sequencer does not automatically reclose this breaker under safety injection conditions; it can be closed manually under administrative
control 31. 1NB01X transformer, item 1, 1E 4160-V switchgear, to item 33, 480-V switchgear, train A
oriented Reduce 4160 V to
480 V A Fail to operate Switchgear trouble alarm in control room None; loss of train A oriented non-1E power; train B oriented non-1E power available
- 32. Breaker 01, (c) item 31 transformer to item 33, 480-V switchgear, train A oriented, normally closed Open on load shedding and
reclose on sequencer program A Fail to open None None Slightly heavier load on initial sequencer step Fail to reclose Alarm in control room; safety equipment failed to start from item 5 sequencer None; partial loss of train A; train B available, but power is train A and B oriented non-1E The sequencer does not automatically reclose this breaker under safety injection conditions; it can be closed manually under administrative control 33. 1NB01, non-1E 480-V switchgear, control building, train A oriented Receive and distribute electric power via breakers A Grounded, bus fault Switchgear trouble alarm in control room Same as 30 System can operate with a single grounded phase VEGP-FSAR-8 TABLE 8.3.1-3 (SHEET 6 OF 12)
REV 14 10/07 Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks
- 34. Breaker 02, (c) item 33, 480-V switchgear, to item 35 MCC, train A oriented, normally closed Provide continuity and protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train A oriented power; train B oriented power available
- 35. 1NBS, non-1E MCC, control building, train A
oriented Receive and distribute electric power
via breakers A Grounded, bus fault Item 33 switchgear
trouble alarm Same as 30 Ground would be sensed and alarmed in control room from item 33 switchgear; system can operate with a single grounded phase
- 36. Breaker 08, (c) item 33, 480-V switchgear, to item 37 MCC, train A oriented, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train A; train B available, but power is train A and B oriented non-1E
- 37. 1NBI, non-1E MCC, diesel generator building, train A oriented Receive and distribute electric power
via breakers A Grounded, bus fault Same as 35 Same as 30 Ground would be sensed and alarmed in control room from item 33 switchgear; system can operate with a single grounded phase
- 38. 1BA03, control building, 4160-V 1E switchgear, train B Receive and distribute electric power via breakers A Grounded, bus fault Switchgear trouble alarm in control room None; loss of train B;
train A available During a LOSP when the bus is fed from the diesel generator, a single ground fault will not cause a trip of
train B 39. Breaker 19, (c) diesel generator 1B power to item 38, 1E switchgear, train B, normally open Close on loss of offsite power and remain closed A Fail to close Alarm in control room; safety equipment failed to start from item 42 sequencer None; loss of train B;
train A available This breaker electrically interlocked with item 40 and item 78 breakers Inadvertent opening Switchgear trouble alarm in control room None; loss of train B;
train A available
- 40. Breaker 01, (c) preferred power to item 38, 1E switchgear, train B, normally closed Open on loss of preferred power and remain open A Fail to open Failure to open alarm in control room from
item 42 sequencer None; loss of train B; train A available This breaker electrically interlocked with item 39 and item 78 breakers Inadvertent closure None None; loss of train B; train A available
VEGP-FSAR-8 TABLE 8.3.1-3 (SHEET 7 OF 12)
REV 14 10/07 Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks
- 41. Diesel generator 1B, train B Provide onsite ac power upon loss of preferred power A Fail to start Diesel generator failed to start alarm in control
room None; loss of train B; train A available Diesel generator started by item 42 sequencer upon loss of preferred power or receipt of a safety injection signal Fail to run Various specific alarms provided in control room
and at local diesel generator control panels None; loss of train B; train A available
- 42. Sequencer, train B Shed all loads from train B Class 1E power system upon loss of preferred power and reconnect all required safe shutdown loads to diesel generator, item 4, via item 1 switchgear in a programmed manner A Fail to operate(d) Switchgear trouble alarm, audio and visual, in control room None; loss of train B; train A available
- 43. Breaker 09, (c) item 38, 1E 4160-V switchgear, to item 44, 1BB16X transformer, train B, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 44. 1BB16X transformer, item 38, 4160-V switchgear, to item 46, 480-V switchgear, train B Reduce 4160 V to 480 V A Fail to operate Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 45. Breaker 01, (c) item 44 transformer to item 46, 480-V switchgear, train B, normally closed Open on load shedding and reclose on sequencer program A Fail to open None None Slightly heavier load on initial sequencer step Fail to reclose Alarm in control room; safety equipment failed to start from item 42
sequencer None; partial loss of train B; train A available
- 46. 1BB16, 1E 480-V switchgear, auxiliary
building, train B Receive and distribute electrical power via breakers A Grounded, bus fault Switchgear trouble alarm in control room Same as 38 System can operate with a single grounded phase
VEGP-FSAR-8 TABLE 8.3.1-3 (SHEET 8 OF 12)
REV 14 10/07 Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks
- 47. Breaker 10, (c) item 46, 480-V switchgear, to item 48 MCC, train B, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 48. 1BBD, 1E MCC, auxiliary building, train B Receive and distribute electric power via breakers A Grounded, bus fault Item 46 switchgear trouble alarm Same as 47 None; would be sensed and alarmed in control room from item 46 switchgear
- 49. Breaker 9, (c) item 46, 480-V switchgear, to item 50 MCC, train B, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 50. 1BBB, 1E MCC, auxiliary building, train B Receive and distribute electric power
via breakers A Grounded Same as 48 Same as 47 None; would be sensed and alarmed in control room from item 46 switchgear
- 51. Breaker 04, (c) item 38, 1E 4160-V switchgear, to item 52, IBB07X transformer, train B, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 52. 1BB07X transformer, item 38, 4160-V switchgear, to item 54, 480-V switchgear, train B Reduce 4160 V to 480 V A Fail to operate Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 53. Breaker 01, (c) item 52 transformer to item 54, 480-V switchgear, train B, normally closed Open on load shedding and
reclose on sequencer program A Fail to open None None Slightly heavier load on initial sequencer step Fail to reclose Alarm in control room; safety equipment failed to start from item 42 sequencer None; partial loss of train B; train A available
- 54. 1BB07, 1E 480-V switchgear, control
building, train B Receive and distribute electric power via breakers A Grounded, bus fault Switchgear trouble alarm in control room Same as 47 System can operate with a single grounded phase
VEGP-FSAR-8 TABLE 8.3.1-3 (SHEET 9 OF 12)
REV 14 10/07 Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks
- 55. Breaker 14, (c) item 54, 480-V switchgear, to item 56 MCC, train B, normally closed Provide continuity
and protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 56. 1BBF, 1E MCC, diesel generator building, train B Receive and distribute electric power via breakers A Grounded, bus fault Item 54 switchgear trouble alarm Same as 47 Ground would be sensed and alarmed in control room from item 54 switchgear
- 57. Breaker 5, (c) item 54, 480-V switchgear, to item 58 MCC, train B, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 58. 1BBC, 1E MCC, control building, train B Receive and distribute electric power
via breakers A Grounded, bus fault Same as 56 Same as 47 Ground would be sensed and alarmed in control room from item 54 switchgear
- 59. Breaker 2, (c) item 54, 480-V switchgear, to item 60 MCC, train B, normally closed Provide continuity and protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 60. 1BBA, 1E MCC, control building, train B Receive and distribute electric power via breakers A Grounded, bus fault Same as 56 Same as 47 Ground would be sensed and alarmed in control room from item 54 switchgear
- 61. Breaker 06, (c) item 38, 1E 4160-V switchgear, to item 62, 1BB06X transformer, normally closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 62. 1BB06X transformer, item 38, 4160-V switchgear, to item 64, 480-V switchgear, train B Reduce 4160 V to 480 V A Fail to operate Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 63. Breaker 01, (c) item 62 transformer to item 64, 480-V switchgear, train B, normally closed Open on load
shedding and reclose on sequencer program A Fail to open None None Slightly heavier load on initial sequencer step VEGP-FSAR-8 TABLE 8.3.1-3 (SHEET 10 OF 12)
REV 14 10/07 Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks Fail to reclose Alarm in control room; safety equipment failed to start from item 42 sequencer None; partial loss of train B; train A available
- 64. 1BB06, 1E 480-V switchgear, control
building, train B Receive and distribute electric power via breakers A Grounded, bus fault Switchgear trouble alarm in control room Same as 47 System can operate with a single grounded phase
- 65. Breaker 02, (c) item 64, 480-V switchgear, to item 66 MCC, train B, normally closed Provide continuity and protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train B; train A available
- 66. 1BBE, 1E MCC, control building, train B Receive and distribute electric power via breakers A Grounded, bus fault Item 64 switchgear trouble alarm Same as 47 Ground would be sensed and alarmed in control room from item 64 switchgear
- 67. Breaker 18, (c) item 38, 1E 4160-V switchgear, to item 68, 1NB10X non-1E transformer, normally
closed Provide continuity and
protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; loss of train B oriented non-1E power; train A orient enon-1E power available The sequencer does not automatically recluse this breaker under SI conditions; it can be closed manually under administrative control
- 68. 1NB10X transformer, item 38, 1E 4160-V switchgear, to item 70, 480-V switchgear, train B oriented Reduce 4160 V to
480 V A Fail to operate Switchgear trouble alarm in control room None; partial loss of train B oriented non-IE power; Train A oriented non-IE power available
- 69. Breaker 01, (c) item 68 transformer to item 70, 480-V switchgear, train B oriented, normally closed Open on load shedding and reclose on sequencer program A Fail to open None None Slightly heavier load on initial sequencer step Fail to reclose Alarm in control room; safety equipment failed to start from item 42 sequencer None; loss of train B; train A available, but power
is train A and B oriented non-1E The sequencer does not automatically reclose this breaker under safety injection conditions; it can be closed manually under administrative control VEGP-FSAR-8 TABLE 8.3.1-3 (SHEET 11 OF 12)
REV 14 10/07 Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks
- 70. 1NB10, non-1E 480-V switchgear, control
building, train B oriented Receive and distribute electric power via breakers A Grounded, bus fault Switchgear trouble alarm in control room Loss of train B oriented non-1E power; train A oriented non-1E power available System can operate with a single grounded phase
- 71. Breaker 02, (c) item 70, 480-V switchgear, to item 72 MCC, train B oriented, normally closed Provide continuity and protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train B; train A available, but power is train A and B oriented non-1E
- 72. 1NBR, non-1E MCC, control building, train B
oriented Receive and distribute electric power
via breakers A Grounded, bus fault trouble
alarm Item 70 switchgear
trouble alarm Same as 70 Ground would be sensed and alarmed from item 70 switchgear
- 73. Breaker 12, (c) item 70, 480-V switchgear, to item 74 MCC, train B oriented, normally closed Provide continuity and protect circuit A Inadvertent opening Switchgear trouble alarm in control room None; partial loss of train B; train A available, but power is train A and B oriented non-1E
- 74. 1NBO, non-1E MCC, diesel generator building, train B oriented Receive and distribute electric power
via breakers A Grounded, bus fault Same as 72 Same as 70 Ground would be sensed and alarmed from item 70 switchgear. System can operate with a single grounded phase
line; train B
- 75. Preferred power from offsite power supply via reserve auxiliary transformer 1NXRA (train A), 1NXRB (train B), or standby auxiliary transformer ANXRA to item 1 switchgear via item 2 or item 77 breaker (non-1E power) Provide preferred power to train A safety-related buses A Loss of power Switchgear trouble alarm in control room None; momentary loss of power until item 4 diesel generator comes on available
VEGP-FSAR-8 TABLE 8.3.1-3 (SHEET 12 OF 12)
REV 14 10/07 Plant Method of Failure Effect Item Description Safety Operating Failure Failure on System Safety No. of Component Function Mode Mode(s) Detection Function Capability General Remarks
- 76. Preferred power from offsite power supply via auxiliary transformer 1NXRB (train B), 1NXRA (train A), or standby auxiliary transformer ANXRA to item 38 switchgear via item 40 or item 78 breaker (non-1E power) Provide preferred power to train B safety-related buses A Loss of power Switchgear trouble alarm in control room None; momentary loss of power until item 41 diesel generator comes on line; train A available
- 77. Breaker 01, (c) alternate preferred power to item 1, 1E switchgear, train A, normally open When closed, opens on loss of preferred power and remains
open A Failure to open Failure to open alarm in control room from
item 5, sequencer None; loss of train A; train B available This breaker electrically interlocked with item 2 and 3 breakers Inadvertent closure Switchgear trouble alarm in control room None; loss of train A;
train B available
- 78. Breaker 05, (c) alternate preferred power to item 38, 1E switchgear, train B, normally open When closed, opens on loss of preferred power and remains
open A Failure to open Failure to open alarm in control room from
item 5, sequencer None; loss of train B; train A available This breaker electrically interlocked with item 39 and 40 breakers Inadvertent closure Switchgear trouble alarm in control room None; loss of train B;
train A available
- a. Plant operating mode A represents a loss of offsite power and/or safety injection; offsite power is the preferred power source. The only postulated failures of interconnecting power cable are a short circuit and/or a ground on the 4-kV system cabling, which would result in inadvertent opening of the associated circuit breaker. All power is reestablished to Class 1E buses following loss of preferred power automatically and requires no operator action.
- b. Unit 1 shown; Unit 2 essentially identical.
- c. It is to be understood that the failure of any one circuit breaker to open when required to under fault conditions will result in the loss or partial loss of the associated train with the redundant train still available.
- d. A Diversity and Defense-in-Depth Analysis addressed software common-mode failure effects.
VEGP-FSAR-8 REV 14 10/07 TABLE 8.3.1-4 (SHEET 1 OF 6)
CIRCUITS ANALYZED FOR SEPARATION REQUIREMENTS A.(a) 1. 7300 Process Control System 2. Nuclear Instrumentation System 3. Solid State Protection System
B. An analysis was performed for selected Unit 1 cables larger than 8 AWG and terminating in multitrain panels. The analysis determined which cables could not ignite under fault conditions (i.e. where there is insufficient available energy or where the backup protection was fast enough to open the faulted circuit before the cables could ignite). Those cables which could not ignite under fault conditions were exempted from separation verification.
C. VEGP generally complies with the separation requirements of IEEE 384-1981. A series of tests and analyses has been performed for circuits of 480-V or lower voltage to establish alternate reduced minimum separation distances where separation distances specified in IEEE 384 are not met. Analyses have also been performed to justify separation of Class 1E 4160-V cables from non-1E 480 V and lower cables. These tests and analyses have been performed as allowed by Sections 6.1.1.3 and 6.6.2 of IEEE 384-1981 and Regulatory Guide 1.75. The test results are documented in Wyle Laboratories Test Report No. 48141-02 and Wyle Laboratories Test Report No. 17959-02, which have been submitted for review by the NRC under separate cover.
Based on the Wyle Laboratories test results,(b) the following minimum separation distances were established:
The separation distances are applied between raceways and cables of any separation group for both vertical (above and below) and horizontal (side by side) physical configurations or as noted.
VEGP-FSAR-8 TABLE 8.3.1-4 (SHEET 2 OF 6)
REV 14 10/07 Minimum Spatial Configuration/Service Level Separation Distance 1. Between trays carrying cables of 480 V or lower voltage of sizes 2/0 AWG or smaller.
12 in. 2. Cables in tray with cover on the bottom from non-class 1E cables in tray or free air (the non-Class 1E cables are limited to 480 V or lower voltage and size 2/0 AWG or smaller and located below or along side Class-1E
tray). 3/4 in. 3. Cables in tray or free air running either vertically, or horizontally (side-by-side) from horizontal non-Class 1E cable in tray (the non-Class 1E cables are limited to 480 V or lower voltage and size 2/0 AWG or smaller).
1 in. 3a. Cables in tray or free air running either vertically, or horizontally (side-by-side) from horizontal non-Class 1E cable in free-air (the non-Class 1E cables are limited to 480 V or lower voltage and size 2/0 AWG or smaller).
1-3/4 in. 4. Tray (a) or free-air cables to a non-Class 1E rigid steel conduit carrying cables of 480 V or lower voltage and sizes 2/0 AWG or smaller.
Contact 4a. Tray or free-air cables to a non-Class 1E rigid steel conduit carrying cables of 480 V or lower voltage and sizes 3/0 AWG through 500MCM.
3/4 in. 5. Tray or free-air cables to a rigid steel conduit (the free-air cables, cables in the tray, and in the conduit are limited to 480 V or lower voltage and size 2/0 AWG or
smaller).
1/2 in. 5a. Cables in tray to a rigid steel conduit routed below or beside the tray (the cables in the tray, and in the conduit are limited to 480 V or lower voltage and size 2/0 AWG
or smaller).
Contact 6. Tray or free-air cables to a non-Class 1E flexible conduit (the non-Class 1E cables are limited to 480 V or lower voltage and size 2/0 AWG or smaller).
1 in. 6a. Tray or free-air cables to a non-Class 1E stripped flexible conduit (the non-Class 1E cables are limited to 480 V or lower voltage and size 2/0 AWG or smaller).
Contact VEGP-FSAR-8 TABLE 8.3.1-4 (SHEET 3 OF 6)
REV 14 10/07 Minimum Spatial Configuration/Service Level Separation Distance 7. Tray or free-air cables to a flexible conduit (the free-air cables, cables in the tray and in the conduit are limited to 480 V or lower voltage and size 2/0 AWG or smaller).
1 in. 8. Tray or free-air cables to a non-Class 1E aluminum sheathed cable of size 8 AWG or smaller or non-Class 1E electrical metallic tubing (EMT) carrying cables of sizes 8 AWG or smaller. (Limited to lighting, communications, and fire detection cables) 1 in. 9. Tray or free-air cables to a non-Class 1E metal-clad cable (type MC) of size 8 AWG or smaller.
3/4 in. 10. Tray or free-air cables to a non-Class 1E steel-armored 480-V cable (500 MCM or smaller).
3/4 in. 10a. Tray or free-air cables (480V or lower voltage and size 2/0 AWG or smaller) to steel-armored 480-V cable (500 MCM or smaller).
3/4 in. 11. Cables in flexible conduit to cables in flexible conduit (the cables are limited to 480 V or lower voltage and size 500 MCM or smaller).
1 in. 11a. Cables in stripped flexible conduit to non- Class 1E cables in stripped flexible conduit (the non-Class 1E cables are limited to 480 V or lower voltage and size 2/0 AWG or smaller).
Contact 11b. Cables in stripped flexible conduit to cables in stripped flexible conduit (the cables are limited to 480 V or lower voltage and size 2/0 AWG or smaller).
Contact 12. Cables in flexible conduit to non-Class 1E cables in rigid steel conduit (the non-Class 1E cables are limited to 480 V or lower voltage and size 2/0 AWG or smaller).
Contact 13. Between two rigid steel conduits (the cables in the conduits are limited to 480 V or lower voltage and size 2/0 AWG or smaller).
Contact 13a. Cables in rigid steel conduit to non-Class 1E cables in rigid steel conduit (the non-Class 1E cables are limited to 480 V or lower voltage and size 2/0 AWG or smaller).
Contact 14. Between perpendicular rigid steel conduits carrying cables of 480 V or lower voltage and sizes 3/0 AWG 1/8 in.
VEGP-FSAR-8 TABLE 8.3.1-4 (SHEET 4 OF 6)
REV 14 10/07 Minimum Spatial Configuration/Service Level Separation Distance through 500 MCM.
- 15. Cables in rigid steel conduit crossing non-Class 1E cables in tray or free air (the non-Class 1E cables are limited to 480 V or lower voltage and size 2/0 AWG or smaller). The angle of crossing shall be 30~ or greater.
Contact 16. Free-air cables to free-air cables, where one of the groups is wrapped in three layers (200 percent overlap) of silicon dioxide cloth (Siltemp 188 CH). Service
voltage is limited to 480 V or lower voltage and sizes of 500 MCM or smaller.
6 in. 16a. From non-Class 1E free air cables 480 V or lower voltage and size of 500 MCM or smaller, wrapped with three layers (200 percent overlap) of silicon dioxide cloth (Siltemp 188 CH) to Class 1E free-air cables.
6 in. 17. Free-air cables 480 V or lower voltage and size of 500 MCM or smaller, to free air control or instrumentation cables (8 AWG or smaller). The control or instrumentation cables are wrapped in two layers (100 percent overlap) of silicon dioxide cloth (Siltemp 188 CH). 1 in. 18. Between free air instrumentation or control cables of 125 V-dc or 120 V-ac or lower, sizes number 8 AWG or
smaller. 1 in. 19. Between free air instrumentation or control cables (125 V-dc or 120 V-ac or lower sizes number 8 AWG or smaller) with either group of cables wrapped in two layers (100 percent overlap) of silicon dioxide cloth (Siltemp 188 CH).
Contact 20. Free-air, class 1E cable(s) to free-air non-class 1E cables with the class 1E cables wrapped in two layers (100 percent overlap) of silicon dioxide cloth. The non-class 1E cables are limited to 480 V or lower voltage of sizes 500 MCM or smaller.
1 in. 21. Within panels and control boards: a. Between instrumentation or control cables of 125 V-dc or 120 V-ac of sizes number 8 AWG or smaller.
1 in.
VEGP-FSAR-8 TABLE 8.3.1-4 (SHEET 5 OF 6)
REV 14 10/07 Minimum Spatial Configuration/Service Level Separation Distance b. Between instrumentation or control cables with either group of cables wrapped in two layers (100 percent overlap) of silicon dioxide cloth (Siltemp 188 CH). The cables are limited to 120 V-ac, 125 V-dc, or lower voltage of sizes number 8 AWG or smaller. Contact c. Separation distances shown for general plant areas in items 4, 5, 6, 10, 13, and 14 have been applied to separation requirements within panels.
- d. Separation distances for cable installed in rigid steel or flexible conduit inside panels are the same as those tested in items 11, 11a, 11b, 12, 13, 13a, and 14.
Where:
Tray - Ventilated (punched bottom) tray or tray fittings, solid bottom tray, or tray fittings
Conduit - Hot dipped galvanized rigid steel conduit
Flexible Conduit - Flexible steel conduit, sealtite, type UA
Steel-Armored -Cable EPR insulation/hypalon jacket with galvanized steel armor. Used for 480-V switchgear loads in tray only.
Aluminum Sheathed -
Cable (ALS) A factory assembly of insulated conductors enclosed in a smooth continuous aluminum sheath. Used for lighting system application.
Metal-Clad Cable -
(MC) A factory assembly of one or more conductors each individually insulated, covered with an overall insulating jacket, and all enclosed in a metallic sheath of interlocking galvanized steel. Used in non-1E circuit only.
Electrical - Metallic Tubing (EMT) Thinwall, steel conduit which conforms to ANSI standard C80.3-1977.
This material provides a barrier equal to, or better than, the aluminum sheathing on ALS because it is manufactured from steel which has higher strength and a higher melting temperature than aluminum.
Free-air cables may consist of steel armored or nonarmored cables, ALS, or type MC cables of any size or voltage level unless otherwise limited in the specific configuration description.
VEGP-FSAR-8 TABLE 8.3.1-4 (SHEET 6 OF 6)
REV 14 10/07 D. Non-class 1E fire detection Protectowire has been used in safety related cable tray within containment to detect cable tray fires. This wiring is installed in a zig-zig fashion along the length of the tray in close proximity to the cables. It consists of two conductors individually encased in heat sensitive material. The encased conductors are twisted together to impose a spring pressure between them. When heated to the critical for operating temperature the heat sensitive material yields to the pressure on it, permitting the conductors to move into contact with each other. A supervisory current of 2.5 mA at a maximum of 26.4 V dc normally flows through the Protectowire. During an alarm condition this current rises to a maximum of 20 mA. Therefore, Protectowire is considered a low energy circuit, which is designed to short during an alarm condition, and cannot cause degradation of any Class 1E cables in the vicinity. A separate Protectowire panel is provided for each train thereby providing electrically independent monitoring of the cable tray temperatures in each train. Based on the discussion above, no separation is required between the non-class 1E fire protection Protectowires and any class 1E cables.
- a. The analyses/tests performed for the above equipment are further described in paragraph
7.1.2.2.1.
- b. The test configuration of target cables above the fault cable represents the worst case, since
heat/flame has tendency to flare vertically upwards.
- c. For the purpose of testing, the cables in the punched bottom tray are considered the same as cables in free air since the cables in the tray are directly exposed to the heat generated by the faulted cable in the areas of the tray that have been punched.
VEGP-FSAR-8 REV 13 4/06 TABLE 8.3.2-1 125-V-dc BATTERY A LOAD REQUIREMENTS (LOCA/LOSP)
Current Required per Time Interval after ac Power Loss (A)
Load Description Unit (b) 0-1 min 1-165 min Random Load 1 441 239 202 2 431 257 174 Total load includes inverters, MOV (a), dc distribution panels,(a,c) dc switchgear, MCC indication and relaying.
- a. The field flash current has not been added to the first period or random load and the MOV current has not been added to the random load since the peak load occurring during the period has been considered. The peak load is due to the breakers closing, which does not occur coincidentally with the field flash or MOV currents.
- b. Differences between switchgear and control load design configurations cause amperages to vary between Units 1 and 2.
- c. The dc distribution panels include the following loads: Class 1E ac switchgear circuit breaker operation, safety features status indication relays and lights, diesel generator field flashing, diesel generator control, reactor trip switchgear, solenoid valves, and Class 1E control cabinet circuit indicators.
VEGP-FSAR-8 REV 13 4/06 TABLE 8.3.2-2 125-V-dc BATTERY B LOAD REQUIREMENTS (LOCA/LOSP)
Current Required per Time Interval after ac Power Loss (A)
Load Description Unit (b) 0-1 min 1-165 min Random Load 1 445 243 202 2 429 255 174 Total load includes inverters, MOV (a), dc distribution panels,(a,c) dc switchgear, MCC indication and relaying.
- a. The field flash current has not been added to the first period or random load and the MOV current has not been added to the random load since the peak load occurring during the period has been considered. The peak load is due to the breakers closing, which does not occur coincidentally with the field flash or MOV currents.
- b. Differences between switchgear and control load design configurations cause amperages to vary between Units 1 and 2.
- c. The dc distribution panels include the following loads: Class 1E ac switchgear circuit breaker operation, safety features status indication relays and lights, diesel generator field flashing, diesel generator control, reactor trip switchgear, solenoid valves, and Class 1E control cabinet circuit indicators.
VEGP-FSAR-8 REV 13 4/06 TABLE 8.3.2-3 125-V-dc BATTERY C LOAD REQUIREMENTS (LOCA/LOSP)
Current Required per Time Interval after ac Power Loss (A)
Load Description Unit (b) 0-1 min 1-165 min Random Load 1 224 92 82.3 2 217 84 82.3 Total load includes inverters, MOV (a), dc distribution panels,(c) dc switchgear, MCC indication and relaying.
- a. The RHR isolation valve is not required to operate when ac power is not available to the RHR system.
- b. Differences between switchgear and control load design configurations cause amperages to vary between Units 1 and 2.
- c. The dc distribution panel includes the following loads: turbine-driven auxiliary feedwater pump control panel, safety features status indication relays and lights, miscellaneous control, and dc switchgear space heaters.
VEGP-FSAR-8 REV 13 4/06 TABLE 8.3.2-4 125-V-dc BATTERY D LOAD REQUIREMENTS (LOCA/LOSP)
Current Required per Time Interval after ac Power Loss (A)
Load Description Unit (b) 0-165 min 1 77 Total load includes inverters, MOV (a), dc distribution panels,(c) dc switchgear, MCC indication and relaying. 2 70
- a. The RHR isolation valve is not required to operate when ac power is not available to the RHR system.
- b. Differences between switchgear and control load design configurations cause amperages to vary between Units 1 and 2.
- c. The dc distribution panel includes the following loads: miscellaneous control and train D switchgear space heaters.
VEGP-FSAR-8 REV 13 4/06 TABLE 8.3.2-5 (SHEET 1 OF 10)
CLASS 1E 125-V dc AND 120-V VITAL ac SYSTEM FAILURE MODES AND EFFECTS ANALYSIS
Item No. Description of Component Safety Function Plant Operating ode Failure Mode(s) Method of Failure Detection Failure Effect on System Safety Function Capability General Remarks
- 1. Redundant Provide dc A, B No output Annunciator in None; item 2 charger For single failure battery charger; power when ac main control room; available; battery analysis; since train A 1AD1CA, power available one battery can provide 2 3/4 h these components train B 1BD1CA and maintain charger trouble without charger; are redundant train C 1CD1CA, battery in a alarm for input train B available to item 2, failure train D 1DD1CA charged undervoltage, of items 1 and 2 condition; either output overvoltage, components would item 1 and/or and loss of require two single item 2 in output failures; thus, service at this would not be any time considered. C No input Annunciator in None; battery This component main control room; available for 4 h cannot function one battery during blackout charger trouble alarm for input undervoltage, output overvoltage, and loss of output
- 2. Redundant Provide dc A, B No output Annunciator in None; item 2 charger For single failure battery charger; power when ac main control available; battery analysis; since train A 1AD1CB, power available room; one battery can provide 2 3/4 h these components train B 1BD1CB, and maintain charger trouble without charger; are redundant to train C 1CD1CB, battery in a alarm for input train B available item 1, failure of train D 1DD1CB charged undervoltage, out-items 1 and 2 condition, either put overvoltage, components would item 1 and/or and loss of require two single item 2 in output failures; thus service at any this would not be time considered
C No input Annunciator in None; battery This component motor control available for cannot function room; one battery 4 h during blackout charger trouble alarm for input undervoltage, output overvoltage, and loss of output
VEGP-FSAR-8 TABLE 8.3.2-5 (SHEET 2 OF 10)
REV 13 4/06 Item No. Description of Component Safety Function Plant Operating Mode Failure Mode(s) Method of Failure Detection Failure Effect on System Safety Function Capability General Remarks
- 3. Battery; train A Backup to battery A, B No output One switchgear None; battery 1AD1B, train B charger trouble alarm in chargers (items 1 1BD1B, train C during load main control room and 2) available; 1CD1B, train D cycling (in for bus train B available 1DD1B rush current) undervoltage, and provide dc ground detection, power for and improper 2 3/4 h without breaker position battery charger output for LOCA/ C No output Control room None; train B LOSP conditions, voltmeter, available and 4 h for SBO annunciator conditions. isolation device panel trouble alarm, loss of related control room equipment indicating lights.
- 4. 125-V dc switch- Distribute A, B, Grounded, One switchgear None; train B Power still available with gear; train A power via C bus fault trouble alarm in available a single ground. 1AD1, train B breakers to main control room 1BD1, train C loads from for bus Power not available with 1CD1, train D chargers and undervoltage, bus fault. 1DD1 battery ground detection, and improper breaker position; for bus fault, no switchgear alarm. Annunciator isolation device panel trouble alarm for bus fault.
- 5. Breaker(b) Provide circuit A, B Inadvertent One switchgear None; item 2 charger train A 1AD106, continuity and opening trouble alarm in available; battery train B 1BD107, protection main control room can provide 2 3/4 h train C 1CD106, between item 1 for bus without charger; train D 1DD106 battery charger undervoltage, train B available and item 4 ground detection, switchgear and improper breaker position C Inadvertent One switchgear None; battery This component opening trouble alarm in available for cannot function main control room 4 h during blackout for bus undervoltage, ground detection, and improper breaker position
VEGP-FSAR-8 TABLE 8.3.2-5 (SHEET 3 OF 10)
REV 13 4/06 Item No. Description of Component Safety Function Plant Operating
Mode Failure Mode(s) Method of Failure
Detection Failure Effect on System Safety Function Capability General Remarks
- 6. Breaker(b) Provide circuit A, B Inadvertent One switchgear None; item 1 charger train A 1AD107, continuity and opening trouble alarm in available; battery train B 1BD106, protection main control room can provide 2 3/4 h train C 1CD107, between item 2 for bus without charger; train D 1DD107 battery charger undervoltage, train B available and item 4 ground detection, switchgear and improper breaker position C Inadvertent One switchgear None; battery This component opening trouble alarm in available for cannot function main control room 4 h during blackout for bus undervoltage, ground detection, and improper breaker position
- 7. Breaker(b) Provide circuit A, B Inadvertent One switchgear None; battery (normally closed); continuity and opening trouble alarm in chargers (items 1 train A 1AD101, protection main control room and 2) available; train B 1BD101, between battery for bus train B available train C 1CD101, and item 4 under voltage, train D 1DD101 switchgear ground detection, and improper breaker position; plus breaker open alarm in main control room
C Inadvertent Control room None; train B opening voltmeter, available annunciator isolation device panel trouble alarm, loss of related control room equipment indicating lights.
- 8. Breaker(b) Provide circuit A, B, Inadvertent Annunciator None; train B (normally closed); continuity and C opening isolation device available train A 1AD109, protection panel trouble train B 1BD109 between item 4 alarm. switchgear and 125-V dc panel 1 (A, B) D12
VEGP-FSAR-8 TABLE 8.3.2-5 (SHEET 4 OF 10)
REV 13 4/06 Item No. Description of Component Safety Function Plant Operating
Mode Failure Mode(s) Method of Failure
Detection Failure Effect on System Safety Function Capability General Remarks
- 9. Breaker(b) Provide circuit A, B Inadvertent One switchgear None; train B (normally closed); continuity and opening trouble alarm in available train A 1AD105, protection main control room train B 1BD105, between item 4 for bus train C 1CD104, switchgear and under voltage, train D 1DD104 125-V dc panel ground detection, 1 (A,B, C, D) and improper D11 breaker position; plus one panel trouble alarm per panel in main control room for bus undervoltage, ground detection, and branch breaker overload. For 1CD104 and 1DD104, failure detection is control room annunciator isolation device panel trouble alarm.
C Inadvertent One switchgear Single failure on For 1CD104 opening trouble alarm in auxiliary feedwater breaker auxiliary main control room turbine-driven pump feedwater for bus control panel function only; undervoltage, functions; blackout for other function ground detection, does not require train D available and improper single failure criteria breaker position; plus one panel trouble alarm per panel in main control room for bus under voltage, ground detection, and branch breaker overload. For 1CD104 and 1DD104, failure detection is control room annunciator isolation device panel trouble alarm.
VEGP-FSAR-8 TABLE 8.3.2-5 (SHEET 5 OF 10)
REV 13 4/06 Item No. Description of Component Safety Function Plant Operating
Mode Failure Mode(s) Method of Failure
Detection Failure Effect on System Safety Function Capability General Remarks
- 10. BreakerLhM Provide circuit A, B, Inadvertent One switchgear None; system safety (normally closed); continuity and C opening trouble alarm in function can be met train A 1AD110, protection main control room with loss of one and 1AD104 between item 4 for bus undervoltage, channel train B 1BD110, switchgear and ground detection, and 1BD104 inverter 1AD1I1, and improper train C 1CD109 1BD1I2, 1CD1I3, breaker position; and 1CD108, 1CD1I5, 1DD1I4, plus inverter trouble train D 1DD109 1DD1I6, 1AD1I11, alarm in main and 1DD108 1BD1I12 control room.
- 11. BreakerLhM Provide circuit A, B Inadvertent One switchgear None; train B For breaker 1AD111 (normally closed); continuity and opening trouble alarm in available and 1BD111 train A 1AD111, protection main control room train B 1BD111, between item 4 for bus undervoltage, train C 1CD111 and 125-V dc ground detection, MCC 1 (A, B, C) and improper D1M breaker position; plus one MCC trouble alarm in main control room for bus undervoltage C Inadvertent One switchgear Single failure on For breaker 1CD111 opening trouble alarm in auxiliary feedwater main control room turbine-driven pump for bus motor-operated undervoltage, valves and ground detection, associated controls; and improper blackout does not breaker position; require single plus one MCC failure criteria trouble alarm in main control room None; train B For breakers for bus undervoltage available 1AD111 and 1BD111.
VEGP-FSAR-8 TABLE 8.3.2-5 (SHEET 6 OF 10)
REV 13 4/06 Item No. Description of Component Safety Function Plant Operating
Mode Failure Mode(s) Method of Failure
Detection Failure Effect on System Safety Function Capability General Remarks
- 12. Inverter; train Convert 125-V A, B,C, No output, Common None; system safety No high ac output for A 1AD1I1, 1AD1I11 dc to 120-V high output annunciator in main function can be met Westinghouse inverters, no train B 1BD1I2, ac and pro-voltage, high control room for with loss of one high dc voltage for Elgar 1BD1I12 train C vide voltage output - Low dc voltage channel inverters, inverter failure for 1CD1I3, train D to vital frequency - High dc voltage solid-state controls inverters 1DD1I4 instrument - Low ac output only. panels 1AY1A, voltage 1BY1B, 1CY1A, - High ac output 1DY1B, 1AY2A, voltage 1BY2B - Inverter trouble.
- 13. Regulated trans- (c) Backup to inverter A, B No output None None; train B For single failure former; (item 12) when available analysis: since train A 1ABB40RX it is isolated these components and 1ABC09RX for maintenance are redundant to train B 1BBB40RX or malfunction item 1, failure of and 1BBA07RX (requires local item 1 and 2 train C 1ABA07RX manual switching components would train D 1BBC09RX at item 14 panel) require two single failures; thus this should not be considered; however, these components are redundant to item 12
C No input None None; train B This component available cannot function during blackout 14. 120-V ac vital Distribute A, B, Ground and Panel trouble None; system safety Power still instrument panel; power via C bus fault alarm in main function can be met available with a train A 1AY1A, breakers to control room with loss of one single ground. 1AY2A, train B loads for ground channel 1BY1B, 1BY2B, detection and bus train C 1CY1A, undervoltage train D 1DY1B
VEGP-FSAR-8 TABLE 8.3.2-5 (SHEET 7 OF 10)
REV 13 4/06 Item No. Description of Component Safety Function Plant Operating
Mode Failure Mode(s) Method of Failure
Detection Failure Effect on System Safety Function Capability General Remarks
- 15. Interlock Provide local A, B, Inadvertent Panel trouble None; momentary breaker(b) one manual switching transfer alarm in main loss of power to per train between inverter control room item 14 panels; (located at (item 12) and for ground train B available item 14 panel) regulated transformer detection and bus (item 13) and undervoltage preclude both being connected A, B Inadvertent Panel trouble None; train B together; also opening alarm in main available provide incoming control room overload protection for ground detection and bus undervoltage
C Inadvertent Panel trouble None; panels are opening alarm in main normally fed from control room inverters which for ground are backed by detection and bus batteries that are undervoltage available for 4 h
- 16. 125-V dc panel; Distribute A, B, Ground, One panel trouble None; train B Power still train A 1AD12, power via C bus fault alarm per panel available available with a train B 1BD12 breakers to in main control single ground loads room for branch breaker overload. Power not available Bus fault will with bus fault. provide an annunciator isolation device panel trouble alarm. Ground detection provided by control room alarm for the panel supply switchgear.
- 17. 125-V dc panel; Distribute A, B, Ground, One panel trouble Same as 16 Power still train A 1AD11 power via C bus fault alarm per panel available with a train B 1BD11 breakers to in main control single ground loads room for bus undervoltage and branch breaker overload. Ground detection provided by control room alarm for the panel supply switchgear.
VEGP-FSAR-8 TABLE 8.3.2-5 (SHEET 8 OF 10)
REV 13 4/06 Item No. Description of Component Safety Function Plant Operating
Mode Failure Mode(s) Method of Failure
Detection Failure Effect on System Safety Function Capability General Remarks
- 18. 125-V dc MCC; Distribute A, B, Ground, MCC trouble None; train B Power still train A 1AD1M, power via C bus fault alarm in main available available with a train B 1BD1M breakers to control room single ground loads for bus undervoltage, and branch breaker overload. Ground will provide a control room alarm for the MCC supply switchgear.
- 19. 125-V dc panel; Distribute A, B, Ground, One panel trouble None; train D Power still train C 1CD11, power via C bus fault alarm per panel available available with a train D 1DD11 breakers to in main control single ground loads room for branch breaker overload. Power not available Bus fault will for bus fault. provide control room annunciator isolation device panel trouble alarm. Ground detection provided by control room alarm for the panel supply switchgear.
C Ground, One panel trouble Single failure; For 1CD104 bus fault alarm per panel in single failure on breaker auxiliary main control room auxiliary feedwater feedwater function for branch breaker turbine-driven pump only; for other overload. Bus space heater and function train D fault will provide control panel available control room functions; blackout annunciator isolation does not require device panel single failure trouble alarm. criteria Ground detection provided by control room alarm for the panel supply switchgear.
VEGP-FSAR-8 TABLE 8.3.2-5 (SHEET 9 OF 10)
REV 13 4/06 Item No. Description of Component Safety Function Plant Operating
Mode Failure Mode(s) Method of Failure
Detection Failure Effect on System Safety Function Capability General Remarks
- 20. 125-V dc MCC; Distribute A, B Ground, MCC trouble alarm None; ac drive train C 1CD1M power via bus fault in main control auxiliary feedwater breakers to room for bus available loads undervoltage, and branch breaker overload. Ground will provide a control room alarm for the MCC supply switchgear.
C Ground, MCC trouble alarm Single failure; bus fault in main control single failure on room for bus auxiliary feedwater undervoltage, turbine-driven pump and branch breaker motor-operated overload. Ground valves and associated will provide a controls; blackout control room alarm does not require for the MCC supply single failure criteria switchgear
- 21. Inverter; Convert 125-V A, B, No output One inverter None; trains A and train C 1CD1I5, dc to 480 V, C trouble alarm per B and train C or D train D 1DD1I6 3 to provide inverter in main available power to operate control room residual heat removal isolation valves 22. Motor starter; Controller for A, B, Inadvertent One starter None; trains A and train C 1CD1I5N, residual heat C opening of trouble alarm per B and train C or D train D 1DD1I6N removal isolation input breaker starter in main available valves control room for loss of voltage and motor overload Motor overload One starter None; trains A and trouble alarm per B and train C or D starter in main available control room for loss of voltage and motor overload No operation No change in None; trains A and status of B and train C or D indicating lights in available main control room
VEGP-FSAR-8 TABLE 8.3.2-5 (SHEET 10 OF 10)
REV 13 4/06 Item No. Description of Component Safety Function Plant Operating
Mode Failure Mode(s) Method of Failure
Detection Failure Effect on System Safety Function Capability General Remarks
- 23. Individual Cell Equalizer None A, B, C Open A. Cell voltage None; the battery cell A short in the reading will be effectively ICE device will B. Measure ICE returned to its fail to an open current. original configuration state.
- a. Plant operating modes are represented as follows:
A - normal (offsite power available). B - loss of offsite power.
C - blackout (loss of all ac systems, except 120-V ac vital system).
System success criteria are as follows:
125-V dc system - one of two (train A or B and train C or D) channels required. 120-V ac vital system - three of four channels required.
- b. It is to be understood that the failure of any one circuit breaker to open when required to under fault conditions will result in the loss of the associated train with redundant train still available.
- c. Unit 2 transformer numbers are suffixed by "RX" in lieu of "X."