Text

Design Approach to Cold Shutdown.
	ML20003H738
Person / Time
Site:	Beaver Valley
Issue date:	04/24/1981
From:	; DUQUESNE LIGHT CO.
To:	;
Shared Package
ML20003H737	List: ML20003H736; ML20003H738;
References
	RTR-REGGD-01.139, RTR-REGGD-1.139 NUDOCS 8105070362
	Download: ML20003H738 (31)
	v • d • e

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_DESIGli APPROAct TO CO2 SN BEAVER VALL7.Y POtfER STATIOgg - UNIT NO. 2 f

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TABLE OF COtfrENTS 1.0 General 2.0 Approach to Safety-Grade Cold Shutdown 2.1 Heat Removal 2.2 Boration 2.3 Depressurization of the Reactor Coolant System 4

2.4 Residual Heat Removal System 2.5 Component Cooling Water Pump Motor Qualifications 3.0 Loss-of-Offsite Power Modifications for Cold Shutdown 4.0 Provisions for Cold Shutdown outside Control Room 4.1 General 4.2 Heat Removal - Outside Control Room 4.3 Boration - Outside Control Room 4.4 BCS Inventory Control - Outside Control Room 4.5 Depressurization - Outside Control Room l

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1.0 GENERAL Beaver Valley Power Station - Unit No. 2 (BVPS-2) is presently designed to maintain Bot Standby as a safe shutdown condition using safety grade compctients.

With the issue of USNRC Regulatory Guide 1.139, " Guidance for Residual Heat Removal", dated May 1978; Branch Technical Position RSB 5-1; and subsequent proposed changes to Reg. Guide 1.139 (i.e. March, 1980 Draft 2 and June,1980, proposed Revision 1), Duquesne Light Company has reviewed the existing design vs. Reg. Guide positions.

Since the BVPS-2 Residual Heat Removal System (RHS) is located inside containment, compliance with Reg. GuiCe 14 33 has more significant impact to design and procedures than a design with outside contain-ment RHS pumps and components.

Duquesne Light Company has investigated upgrade to Cold Shutdown utilizing R.G.1.139 as a basis and shall provide an " approach" to Safety-grade Cold Shutdown, wherever feasible, incluMng aspects of loss-of-of fsite power. Additionally, the design being considered i

has provisions for Cold Shutdown outside the Control Room.

This Design Concept is intended to amplify the approach taken by Duquesne Light Company as an upgrade frca a Hot Standby designed plant through compliance with the intent of Reg. Guide 1.139, with an approach to Safety-grade Cold Shutdown capability. The presentation is mainly technically oriented and does not address every aspect of the regulatory guide. However, th? information is intended to clearly identify the various concepts utilized in the overall approach. The inforntion is organized to present the " Approach to Safety Grade Cold Sautdown" first, followed by " Loss-of-offsite Power Modifications ict Cold Shutf.own", and " Provisions for Cold Shutdown outside Cortrol Room" last.

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2.0 APPROACH TO SAFETY-GRADE COLD SHUTDOWN 2.1 Heat Removal Initially Beaver Valley Power Station, Unit No. 2 is brought to Hot Standby by the insertion of control rods and maintained in this condition until cooldown to cold conditions is initiated.

During this time, at Hot Standby, residual heat is removed by utilization of the Auxiliary Feedwater System and the steam generators. If there is a loss of offsite power, natural f

circulation of reactor coolant is relied upon to transfer heat j

.l from the core to the steam generators.

For the first stage of cooldown, heat removal is also accom-plished by the Auxiliary Feedwater tiystem in conjunction with steam release from the steam generators. For purposes of specifying the volumetric requirements of auxiliary feedwater it is assumed that the plant remains at hot standby and boration for 11 hours1.273148e-4 days 0.00306 hours 1.818783e-5 weeks 4.1855e-6 months and is cooled to 3500F in another 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months as the preferred method. In order to maintain long-term hot standby (greater than 16 hours1.851852e-4 days 0.00444 hours 2.645503e-5 weeks 6.088e-6 months ) and provide adequate cooldown within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months to initiate residual neat removal, tne steam generator power operated relief valves must be safety-grade and an adequate supply of Auxiliary Feedwater must be established.

i The design review of these two concerns has resulted in the following modifications:

l 2.1.1 Atmospheric Steam Dump Capability (See Figure 1)

1. In the establishment of a Safety-giade Atmospheric Steam Dump Capability (steam generator PORV's) to provide cooldown to Residual Heat Removal System l

initiation, the tollowing criteria were utilized:

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a) Two (2) steam generators are required for cool-down.

b) Single failure is assumed.

c) All valves and piping are Seismic Category I, QA Category I, Safety Class 2.

d) All remote operated valves are Class IE, environ-l mentally qualified to IEEE 323-74 and IEEE 344-75.

Other applicable standards include IEE 279-71, ,

382-72, and 384-77.

I e) Maximum 36-hour period from normal RCS temperature l to 3500F (RHS initiation), including 11 hrs. of hot standby and boration and 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months of cooldown.

l f) Steam generator water lavel maintained at normal zero load band.

2. As a back-up to utilizing steam generator PORV'e fc.c cooldown, the design change currently being imple-mented by Duquesne Light Ccepany is to provide a larger capacity Residual Heat Release Valve (2SVS*HCV104) qualified to full safety-grade design.

This design change will allow long-term cooldown of 31 hours3.587963e-4 days 0.00861 hours 5.125661e-5 weeks 1.17955e-5 months of hot standby and 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months of cooldown, through the HCV as an alterna;e (redundant) method to the two-out-of-three existing steam generator PORV's (2SVS*PCv101A,101B, & 101C) with sufficient capacity to meet the total . Cold Shutdown mass flow for two r

steam generators, necessary to meet RHS initiation l criteria (within 36 hours4.166667e-4 days 0.01 hours 5.952381e-5 weeks 1.3698e-5 months ).

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3. The electric power supply for the three steam gener-ator PORV's will be placed on one IP. Bus (orange),

while the HCV valve will be on the other IE Bus (purple), thus providing redundancy of power supply.

4. Piping from PORV's and BCV from outlet to vent on the Main Steam Valve house roof will be designed as Seismic Category I, QA Category I, Safety Class 2.

The piping in this area has been analyzed such that i these lines qualify as a " break exclusion zone".

Eigure 1 depicts a simplified flow diagram for the PORV's and HCV, including power supplies (orange; AO, BO, CO; purple, ZP) as well as approximate line sizes.

l 2.1.2 Adequate Supely of Auxiliary Feedwater

1. The NSSS Supplier's study defined a time period of 11 hours1.273148e-4 days 0.00306 hours 1.818783e-5 weeks 4.1855e-6 months at hot standby and boration followed by 5 hours5.787037e-5 days 0.00139 hours 8.267196e-6 weeks 1.9025e-6 months of cooldown to 350 0F.

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2. The present auxiliary feedwater storage tank (2FWE-TK210) has a capacity of 140,000 gallons, sufficient for maintaining hot standby for 3 hours3.472222e-5 days 8.333333e-4 hours 4.960317e-6 weeks 1.1415e-6 months followed by a 4 hour4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months cooldown to 3500 F in the RCS, assuming a maximum water temperature o? 1200F and no makeup to the tank.

3. Af ter review of this concern, it was jointly agreed i

l between Duquesne Light Company and its suppliers that 1

the present Service Water System supply connections

! would be used as a safety-grade backup, if necessary.

4. To delay the of use of Service Water as long as possible and to provide more time before a decision to

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1 go to Cold Shutdown must be made, a cross-connection between the 600,000 gallon Domineralized Water Sto-rage Tank and the 140,000 gallon auxiliary feedwater storage tank has been implemented. The cross-connection will be normally closed with two locked ,

closed valves to maintain the safety related pressure boundary of the Auxiliary Feedwater Storage Tank, sinecs FAa 600,000 gallon tank is not safety-related.

f Although no licensing credit is assumed for this dodification, it will increase plant operation flex-ibility by providing sufficient water to maintain hot standby for 2-3 days.

2.2 Boration (including LetdowQ

) 2.2.1 Boration (!ee Figures 2 and 3) .

1. The safety grade means of injecting boron into the BCS is provided by utilizing the HHSI/ charging pumps to i

inject 4 wt. percent boric acid from the Boric 7.:id i'

Tank via Boric Acid Transfer Pumps or 2000 PPM bo ?ted

! water from the Refueling Water Storage Tank , This design was selected to address restrictions con-cerning local operator action. Charging pump throt-tling capability is added to allow charging flow control during shutdown operation.

2. The throttling capability modification consists of two (2) redundant paths for RCS cold leg injection, l

including solenoid operated throttling valves and motor operated isolation valves (See. Figure 2). All valve operators will be qualified to IEEE 323-74 and IEEE 344-75.

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3. Safety grade monitoring of each HHSI charging flow path will be provided with flow transmitters (FT-940 and FT-943) qualified to IEEE 323-74 and 344-75 (See Figure 3). These flow transmitters will be suf-ficient for both cold shutdown and post-accident monitoring requirements (Reg. Guide 1.97). The Boric Acid Tank level instrumentation (Safety Grade) will confirm the volume of 4 wt. percent boric acid injected into the Ret.c. tor Coolant System. .

2.2.2 Letdown (See Figure 4)

1. The safety grade means of letdown is provided by the addition of a letdown line connection from the reactor vessel head to the Pressurizer Relief Tank.

The parallel and series valve arrangement provides reactor coolant letdown via redundant safety compo-nents.

i An additional benefit is that the connection provides a piped vent for normal plant startup, thereby reducing personnel exposure and fluid handling during normal venting operations. With the use of 4 percent boric acid, a one inch line provides sufficient letdown to achieve a 4 hour4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months boration period, consis-tent with the NSSS Supplier's Cold Shutdown Design bases.

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( reactor vessel head letdown system also provides a

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3. All active valve operators included in the Peactor Vessel Head Letdown and Vent System will be qualified to IEEE 323-74 and 344-75.

2.3 Depressurization of Reactor Coolant System 2.3.1 Pressurizer Power-Operated Relief Valves (See Figure 5)

The safety-grade derign proposed for depressurizini the RCS involves venting from the pressurizer to the Pres-surizer Relief Tank via new safety-grade solenoid Aper-ated power operated relief valves (PORV's). The new PORV's will be revised from control grade to protectica grade classification (including qualification to IEEE 323-74 and 344-75).

2.3.2 Pressurizer Motor Omrated Block Valves (See Figure 5)

The existing block valves will be upgraded as active valves for operation during post-accident conditions and to isolate a leaking PORV. The new valve operators will be qualified to IEEE 323-74 and IEEE 344-75.

l 2.3.3 Safety Injection Accumulator Vents (See Figure 6)

The Safety Injection Accumulator Nitrogen Supply Valves and Common Vent Header will be modified to provide redundant Class IE power supplies. Each SI Accumulator will be provided with two parallel nitrogen isola-tion / vent valves, while two parallel vent valves will be provided on the vent header. The valve operators will be

! qualified to IEEE 323-74 and 344 ~15.

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2.4 Residual Heat Removal System (RHS)

Since the RHS is located inside contain3ent for BVPS-2, the approach to safety grade has included a considerable number of audifications. The following are the mejor changes presently being implemented or investigated:

2.4.1 RBS Flow Transmitter 2 (See Figure 7)

Flow transmitters (F'l-605A and 605B) qualified to Class IE (IEEE 323-74) for inside containment use will be provided as an upgrade fer cold shutdown. Relocation cf transmitters above the maximum flood level shall also ba hplemented.

i 2.4.2 RHS Flow Control Valves (See Figure 7)

An upgrade of flow control valves (HCV 758A and 758B and FCV 605A and 605B) from motor operated (modulated) valves to air operated valves has been implemented for

! higher reli' ability. Restriction orifices will also be added to prevent RES pump runout during safety-grade operation with the assumption that new air-operated control valves fail in safe position (i.e. SCV-758 A&B Fail Open and FCV-605 A&B Fail Closed).

2. 4 . ':i RES Valve Relocation (See Figure 7)

Af ter a thorough investigation of alternatives (i.e.

motor actuator encapsulation, motor relocation with extended shaft, etc.), relocation of RHS suction and discharge valves has been implemented to location above the maximum flood leiel as part of the approach to safety-grade cold shutdcun. The valves (MOV 701A, 701B, 702A, 702B, 720A, and 720B) are normally closed as part of the pressure boundary between the Reactor Coolant l

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2.4.4 RHS Suction Valve Power Supplies (See Figure 8)

1. Four motor-operated valves (MOV 701A, 701B, 702A, And 702B) are provided in the piping freet the RCS loop'to the RBS pumps. Each pump suction line includes two of these valves, each powered from a different Class IE bus. A failure of either bus will prevent operation of the RHS System, since one valve, associated with the failed bus, in each suction line could not be opened.

2. All valves are located inside containment with their motor control centers (MCC) lo.:ated in the cable vault and rod control area. Only valves Mov 701B and 702A need to oe provicec witn an alternate power supply, since failure of the bus supplying the recond valve on each suction line would also affect the pump power supply of that suction line. Therefore, only these two valves, wnich are powered from the opposite bus as their associated RHS pump, have to be provided witn power supplies tros both Class IE buses.

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3. The proposed method, currently being implementud, is similar to that used for the swing (installed apare)

! HHSI/ Charging pump and swing Service Water pump. A power supply tros each MCC will be wired to a local enclosure in the cable vault and rod control area containing two mechanically interlocked breaker as-semblies. Each power supply will also have a set of

breakers between the MCC and the enclosure. Mechani-cal interlocks and unique keys will be utilized to prevent closure of all breakers at once and cross-connection of both Class IE buses.

The proposed transfer break assembly (transfer swi-tch) will consist of two molded case " Breaker Assen-blies" each with two breakers in series. The transfer switch will incorporate a mechanism to al'4ow the breakers to oe locked in the "open" or " closed" position by means of a key lock system. The " Breaker Assemblies" will be interlocked to prevent simul-taneous power supply (from both IE buses) to the selected valve. All equipment included in the Transfer switch will be qualified to IEEE 323-74 and 344-75. 'The three-cmpartment enclosure will meet separation criteria in accordance with Reg. Guide 1.75, Rev. 2 and shall be seismically qualified.

4. Although utilization of the alternate power supply will defeat the safety related interlocks (which prevent opening or automatically closing the suction valves when the RCS pressure is above the RHS system design) for the two referenced valves, the remaining two valves, one in each train, will continue to be -

interlocked. The loss of control interlocks af ter manual transfer is considered acceptable, since a prior failure must already have occurred to require electrical transfer, and only one single failure need~~~

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2.4.5 RHS Pump Motor Qualification The RHS pump motors are non-class IE motors and are located inside containment. An initial investigation determined that the RHS pump motor full qualification testing is presently infeasible from aspects of industry i capability as well as factors relating to schedule impact and high cost.

Duquesne Light Company has initiated subsequent investi-gation, as an " Approach to Safety-grade", for environment-al qualification of the RHS pump motor. This approach includes investigation by the NSSS Euppliar, with evalu-ation by the A/E-Constructor and Duquesne Light Company, teto the ability of the motor materials to withstand radiation exposute and high temperature transients. At the conclusion of this investigation, a licensing posi-tion will be developed.

2.5 Component Cooling Water Pump Motor Qualification i

Use of the CCP pumps for safety-grade cold shutdown requires that the qualification include accident environments. The CCP l

pump motors, located in the Auxiliary Building, have been included in the BVPS-2 Envircamental Qualification program.

3.0 LOSS-OF-OFPSITE POWER MODIFICATICN FOR COLD SHUIDOWN (See Figure 9) l I

Although the basic licensing approach to BVPS-2 upgraded design is an

" Approach to Safety-Grade Cold Shutdown" which is independent of offsite power (See Section 2.0); Duquesne Light Company also recognizes that achievement of cold shutdown, utilizing normally available non-safety-grade systems and components, is desirable with postulation of loss-of-offsite power (IDP) as the initiating event.

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Pursuant to t sis concern, Duquesne Light reviewed the normally available systems (control grade) necessary to achieve Cold Shutdown with LOP and determined that a relati'tely limited number of control grade components were affected.

For this upgrade, all air operated valve solenoids which are applicable to normal enarging ano letdown paths will be supplied with new " Black" diesel-generator tdedicated, non-IE bus) power. In addition, the " Black" diesel generator bus will provide power for a non-safety grade air compressor, which supplies back-up air to the AOV's, to flow control valve FCV-122, and PCV 145.

4.0 EROVISIONS FOR COID SHUTDOWN OUTSIDE CottfROL ROOM 4.1 General .

1. The present Emergency Shutdown Panel (ESP) locate $ outside

'.t control room was established to provide an alternate means of safe shutdown (to Hot Standby) in the event of control room inhabitability.

2. Since this requirement excludes accident postulation other than control room inhaoitability, the ESP is not safety-related.

3. Table 1 lists the components which could be controlled from the ESP and those other plant parameters which could be monitored p ior to the cold shutdown modifications.

4. Table 2 lists the modifications included for cold shutdown to controls and monitoring.

5. Presented below are the present and modified functions to the ESP in the approach to Cold Shutdown outside the control room for Heat Removal, Boration, RCS Inventory Control, and Depressurization.

4.2 Heat Removal - Outside Control Room (See Figure 10)

1. Cooldown from RCS normal operating conditions to 350 0F using the auxiliary feedwater pumps, supply valves, and atmospheric steam dump valves (steam generator PORV's) can be controlled from the ESP, as initially designed. In addition, steam generator level, RCS hot leg and cold leg temperatures are also included in the intial design.

2. The RHS must be initiated when the ECS reaches 3500 F to ,

continue cooldown. Controis tor the Service Water System Pumps (SWS), Component Cooling Wator Pumps (CCP), and Residual Heat Removal Pumps (RHS) and indication of the RHS heat exchanger outlet temperature are available at the ESP as initially designed. To provide RHS cooling, the following modification will be implemented: Controls for CCP supply valves to the RHS neat exchanger, RHS isolation and flow control valves, and RHS flow indication.

3. The SI accumulator isolation valves and controls for blocking safety injection initiation will be included in the ESP modification.

4.3 Boration - Outside Control Room (See Figure 11) -

1. Boration of the RCS, pressurizer, and RHS utilizes the Charging pumps, Boric Acid Transfer Pumps, charging and auxiliary spray flow paths and the Boric Acid Tanks or Refueling Water Storage Tank. The normal charging path. .

isolation valve MOV 310, charging flow ~ control valve FCV122, aux 111ary spray valve MOV 311 and temperature monitor of auxiliary spray TE 123 were not included in the initial design and will be included in the ESP modification.

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2. Boration of the RHS via the crossconnection to the letdown line requires operation of BCV142 and the two new MOV's (.N and MOVXXXB) being added to the RBS pump discharges. Operation of these valves will be included in the ESP modification, as they are located inside contain-ment and : manual operation is difficult.

3. The Charging pump suction lines frcus the Boric Acid Tank, volume Control Tank and letST include valves MOv350; LCV ll5C and Ic/115E; and ICI 115D and IC/ ll5B, respectively, all of which will be included in the ESP modification.

4.4 BCS Inventory Control - Outside Control Room (See Figure 11)

1. The charging is required and the letdown flow paths, Volume Centrol Tank and Coolant Recovery Tanks are beneficial for inventory control. Modifications to the ESP, in addition to those identified in 4.3, include LC"I 460A, Irv 460B, ACV 204, PC"I 145, and two new valves (MOVYYYA and MCMmfB) added to provide letdown to the BVPS-1 Coolant Recovery Tanks.

2. Pressurizer level indicates LT459 and LT460 will also be included in the ESP modification. "

4.5 Depressurization - Outside Control Room The Charging pumps via the auxiliary spray line provide aCS depressurization capability. RCS pressure indication PT 402 and PT 403 has been provided on the ESP with the initial design.

The ESP unlification will include charging path temperature monitoring with TE 123.

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I TABLE I EMERGENCY SHUTDOWN PANEL - PRESENT Co m 0LS/ INDICATION l

@ Item / Mark No. Control / Indication Components I Auxiliary Feedwater Motor-driven pumps 2 die *P23A, B

- Control Sw./ Indicating Lights g Steam supply valves to Turbine-driven Control Sw./ Indicating Lights S Aux. Feed Pumps 2 MSS *A0V105A,B Primary Plant Component Cooling Water Control Sw./ Indicating Lights I Pumps 2CCP*P21A, B, C Service Water Pumps 2SWS*P21A, B, C Control Sw./ Indicating Lights Atmospheric Steam Dump Valves Manual Indicating Controller 2SVS*PCV101A, B, C Residual Heat Removal Pumps Control Sw./ Indicating Lights 2RHS*P21A, B Letdown Orifice Isolation Valves Control Sw./ Indicating Lights 2CHS*A0V200A, B, C Charging Pump Flow Control Valve Manual Indicating Controller

i. 2CHS*FCV122 g Containment Air Recirculation Control Sw./ Indicating Lights g Cooler Fans 2HVR*FN201A, B, C CRDM Shroud Fans 2HVR*FN202A1, Control Sw./ Indicating Lights

~

B1, C1, A2, B2, C2 Pressurizer Backup Heaters Control Sw./ Indicating Lights Groups A, B l Boric Acid Transfer Pumps Control Sw./ Indicating Lights 2CHS*P22A, B Auxiliary Feed Pu=p Discharge Control Sw./ Indicating Lights Valves 2FWE*HCV100A-F Charging Pumps 2CHS*P21A, B, C Control Sw./ Indicating Lights t g Emergency' Diesel Generators Start-Stop Pushbuttons I

g 2EGF*EG2-1, 2 Supply Breakers between Control Sw./ Indicating Lights l Normal and Emergency Buses - 42A,

! 3423, 2A10, 2D10, 2E7, 2F7 F

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m tE i DfERGENCY SHUTDOW PANEL - PRESENT CONTROLS / INDICATION Co= trots / Indication O Ite.< Mark No.

Supply Breakers - Emergency Control Sv./ Indicating Lights Diesel Generators 2E10, 2E10 Indications Auxiliary Feedvater Flov 2 Pt. Indicator 2DE*IT100A, 3, C 1 Pt. Indicator 2 Pt. Indicatcr Steam Generator Level 2EVS*LT477, 487, 497 1 Pt. Indicator Steam Generator Pressure 2 Pt. Indicater 2 MSS *PT474, 485, 496 1 Pt. Indicator Source and Intermediate Range 4 Pt. Indicator Neutron Detectors - Level and Startup Rate Indication RER Heat Exchanger Outlet 1 Pt. Indicator Temperature 2RES-TE606A, 3 1 Pt. Indicater.

4,160 V Emergency Eus Voltage Voltmeter Buses 2AE, 2DF p

Pressurizer Level 1 Pt. Indicator 2RCS*LT459, 460 1 Pt. Indicator I

E Pressurizer Pressure 1 Pt. Indicator 2RCS-IT444, 455 1 Pt. Indicator RCS Loop Hot Leg Te=perature 3 Pt. Indicator l

2RCS*IE413, 423, 433 RCS Loop Cold Leg Te_.perature 3 Pt. Indicator 2RCS*TE410, 420, 430 l

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TABLE 1 DESIGN CHANGES TO ESP O Item / Mark No. Control / Indication CGP Supply Valves to RHS Heat Exchangers Control Sw./ Indicating Lights 2CCP*MOV112A, B RHS Isolation Valves Control Sw./ Indicating Lights 2RHS*MOV701A, B 2RHS*MOV702A, B 2RHS*MOV720A,B RHS Flow Control Valves Manual Indicating Controller 2RHS*FCV605A, B 2RHS*HCV758A, B ,

Charging Flow Path Valve Control Sw./ Indicating Lights 2CHS*MOV310 Auxiliary Spray Valve Control Sw./ Indicating Lights I 2CHS-MOV311 RHS Crossconnection Valves Control Sw./ Indicating Lights l W S*MOVXXXA, B 2CHS*HCV142 Manual Indicating Controller Pressurizer Low Level Isolation Control Sw./ Indicating Lights

)1 Valves 2CHS*LCV460A, B .

a Letdown Valves to Coolant Control Sw./ Indicating Lights Recovery Tanks l~ y 2CHS*MOVXXXA, B Letdown Valve Outside Containment Control Sw./ Indicating Lights 2CHS*A0V204 11 Air Supply Solenoid Valves for:

l 2CHS*A0V204 M' Control Sw.

2CHS*FCV122 Charging Pump Suction Valves Control Sw./ Indicating Lights 2CHS*LCV115B, C, D, E

(( SIS Accumulator Isolation Control Sw./ Indicating Lights /

M Isolaton Valves 2 SIS *M0V865A, B, C Banana Plugs (Electrical Power Removal)

SI Safety Injection Blocking Controls ControiSw.

Train A, B l7 j 1 of 1 Y

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.] E RHS Flow Instrumentation 1 Pt. Indic2 tor Q 2RHS-FT605A, B Charging Flow Path Temperature Instrumentation 1 Pt. Ir. dica te r 2CHS*TE123 l

Charging Flow Instrumentation 1 Pt. Indic.. tor 2CHS-FT122 VCT Level Instrumentation 2 Pt. Indicato:

2CHS-LT112, 115 NOTE: Transfer switches must le provided for all controls on 0.e ESP.

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