ML18039A824

Proposed Tech Specs Providing TS for Operation of Oscillation PRM Upscale Trip Function in Aprm,Which Is Part of Power Range Neutron Monitoring Sys

ML18039A824
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Site:	Browns Ferry
Issue date:	07/28/1999
From:	TENNESSEE VALLEY AUTHORITY
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ML18039A823	List: ML18039A822 ML18039A824
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NUDOCS 9908040132
Download: ML18039A824 (69)

Text

TS-398 BFN UNIT 3 MARKED-UP PAGES 9908040i$ 2 990728 PDR ADOCK 05000296',

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3.3 INSTRUMENTATION 3.3.1.1 Reactor Protection System (RPS) Instrumentation RP S Instrumentation 3.3.1.1 LCO 3.3.1.1 The RPS instrumentation for each Function in Table 3.3.1.1-1 shall be OPERABLE.

APPLICABILITY:

According to Table 3.3.1.1-1.

ACTIONS NOTE Separate Condition entry is allowed for each channel.

CONDITION REQUIRED ACTION COMPLETION TIME A. One or more required channels inoperable.

A.1 Place channel in trip.

OR 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> A.2 NOTE Not applicable for Functions 2.a, 2.b, 2.c, 2.

) r Z.f.

Place associated trip system in trip.

12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> (continued)

BFN-UNIT3 3.3-1 Amendment No. 213 September 03, 1998

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RPS Instrumentation 3.3.1.1

'CTIONS continued CONDITION REQUIRED ACTION COMPLETION TIME NOTE Not applicable for Functions 2.a, 2.b, 2.c,lQ) 2.Q t or 2,+.

One or more Functions with one or more required channels inoperable in both trip systems.

B.1 Place channel in one trip system in trip.

8.2 Place one trip system in trip.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 6 hours C. One or more Functions with'PS trip capability not maintained.

l C.1 Restore RPS trip capability.

1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> D. Required Action and associated Completion Time of Condition A, B, or C not met.

D.1 Enter the Condition referenced in Table 3.3.1.1-1 for the channel.

Immediately E. As required by Required Action D.1 and referenced in Table 3.3.1.1-1

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E.1 Reduce THERMAL POWER to < 30% RTP.

4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> F. As required by Required Action D.1 and referenced in

'able 3.3.1.1-.1; F.1 Be in MODE 2.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> (continued)

BFN-UNIT3 303 2 Amendment No. 213 September 03, 1998

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RPS Instrumentation 3.3.1.1

'ACTIONS continued CONDITION REQUIRED ACTION COMPLETION TIME G. As required by Required Action D.1 and referenced in Table 3.3.1.1-1.

G.1 Be in MODE 3.

12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> H. As required by Required Action D.1 and referenced in Table 3.3.1.1-1.'.1 Initiate action to fully insert all insertable control rods in core cells containing one or more fuel assemblies.

Immediately

~nger+4 BFN-UNIT3 3.3-3 Amendment No. 213 September 03, 1998

I.

As required by Required Action D.1 and referenced in Table 3.3.1.1-1.

I.1 Initiate alternate method to detect and suppress thermal hydraulic instability oscillations.

AND I.2 Restore required channels to OPERABLE.

12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> 120 days Required Action J.1 Be in Mode 2.

and associated Completion Time of Condition I not met.

4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />

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RPS Instrumentation 3.3.1.1

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SURVEILLANCEREQUIREMENTS continued SURVEILLANCE FREQUENCY SR 3.3.1.1.10 Perform CHANNELCALIBRATION.

184 days SR 3.3.1.1.11 (Deleted)

SR.3.3.1.1.12 Perform CHANNELFUNCTIONALTEST.

24 months SR 3.3.1.1.13 NOTE Neutron detectors'are excluded.

Perform CHANNELCALIBRATION.

24 months SR 3.3.1.1.14 Perform LOGIC SYSTEM FUNCTIONAL TEST.

24 months SR 3.3.1.1.15 VerifyTurbine Stop Valve - Closure and Turbine Control Valve Fast Closure, Trip Oil Pressure

- Low Functions are not bypassed when THERMALPOWER is z 30% RTP.

24 months SR 3.3.1.1.16 NOTE For Function 2.a, not required to be performed when entering MODE 2 from MODE 1 until 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after entering MODE 2.

Perform CHANNELFUNCTIONALTEST.

184 days

&nrem Q B BFN-UNIT3 3.3

~ Amendment No. 215 November 30, 1998

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IRsKRT B SR 3.3.1.1.17 VerifyOPRM is not bypassed when APRM Simulated Thermal Power is) 25% and recirculation drive flow is ( 60% ofrated recirculation drive fiow.

24 months

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RPS Instrumentation 3.3.1.1 Table 3.3.1.1-1 (page 2 of 3)

Reactor Protection System Instrumentation FUNCTION APPLICABLE MODES OR OTHER SPECIFIED CONDITIONS REQUIRED CHANNELS PER TRIP SYSTEM CONDITIONS REFERENCED FROM REQUIRED ACTION D.1 SURVEILLANCE ALLOWABLE REQUIREMENTS VALUE 2.

Average Power Range Monitors (continued) d.

Inop e.

2-Out-Ofd Voter Xny~ C 1,2 12 3(b)

G SR 3.3.1.1.1 SR 3.3.1.1.14 SR 3.3.1.1.16 NA SR 3.3.1.1.16 NA 3.

Reactor Vessel Steain Dome Pressure

- High 4.

Reactor Vessel Water Level-Low, Level 3 5.

MaIn Steam Isolation Valve-Closure 6.

Drywall Pressure - High 1,2 1,2 1,2 SR 3.3.1.1.1 SR 3.3.1.1.8 SR 3.3.1.1.10 SR 3.3.1.1.14 SR 3.3.1.1.1 SR 3.3.1.1.8 SR 3.3.1.1.13 SR 3.3.1.1.14 SR 3.3.1.1.8 SR 3.3.1.1.13 SR 3.3.1.1.14 SR 3.3.1.1.8 SR 3.3.1.1.13 SR 3.3.1.1.14 s 1090 pslg I

a 538 inches above vessel zero S 10% closed s 2.5 psig 7.

Scram Discharge Volume Water Level - High a.

Resistance Temperature Detector b.

Float Switch 1.2 5(a) 1,2 5(a)

H SR 3.3.1.1.8 S 50 gallons SR 3.3.1.1.13 SR 3.3.1.1.14 SR 3.3.1.1.8 s 50 gallons SR 3.3.1.1.13 SR 3.3.1.1.14 SR 3.3.1.1.8 S 50 gallons SR 3.3.1.1.13 SR 3.3.1.1.14 SR 3.3.1.1.8 S 50 gallons SR 3.3.1.1.13 SR 3.3.1.1.14 (continued)

(a)

With any control rod withdrawn from a core cell containing one or more fuel assemblies.

(b)

Each APRM channel provides inputs to both trip systems.

BFN-UNIT3 3.3-8 Amendment No: 214 September 08, 1998

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INSERT C I

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OPRM Upscale SR 3.3.1.1.1 SR 3.3.1.1.7 SR 3.3.1.1.13 SR 3.3.1.1.16 SR 3.3.1.1.17 NA

Recirculation Loops Operating 3.4.1

>3.4 REACTOR COOLANTSYSTEM (RCS) 3.4.1 Recirculation Loops Operating LCO 3.4.1 Two recirculation loops with matched fiows shall be in o eration.

ith re wa afu iong THE LP WE utsid egons and land he 0 ratio otP rmitte Regip of F'pure

.4.1 OR h

One recirculation loo ma be in o eratio ith re ow a

n on fTHJK LP W outyide ion la II dthe Op rat'N fPe itt Re ion f'Fi u 3.

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providedthe fo owing imits are applied when the associated L

is applicable:

P a.

LCO 3.2.1, "AVERAGEPLANARLINEARHEAT GENERATION RATE (APLHGR)," single loop operation limits specified in the COLR; b.

LCO 3.2.2, "MINIMUMCRITICALPOWER RATIO (MCPR),'ingle loop operation limits specified in the COLR; c.

LCO 3.3.1.1, "Reactor Protection System (RPS)

Instrumentation, Function 2.b (Average Power Range Monitors Flow Biased Simulated Thermal Power - High), Allowable Value of Table 3.3.1.1-1 is reset for single loop operation; APPLICABILITY:

MODES 1 and 2.

BFN-UNIT3 3 4-1 Amendment No. 216 December 23, 1998

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Recirculation Loops Operating 3.4.1

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ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. R actoro eration ith re flo as a fu ion of THER L PO ER insid of Reg' I of Fi re 3.4.1 1.

1 Place ode switch in e

shu own position.

Immediatet B. Reacto operatio with core was af nctionof THE MALP ER insj e of Re ion II of F'pure 3.4. -1.

AND Place mo e switch in the shutdo position.

P Immediately u on discovery o thermal hy raulic instabil'tg B.2 Exit Region 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> t

A P Requirements 0

not met.

r as s

h ta A r Satisfy the requirements of the LCO.

24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />

. Required Action and associated Complet'ime of Conditio not met.

J5.1 Be in MODE 3.

8 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> OR No recircul tip oops in o eration.

fl in'D E.

o re rculat' lo s in operation ile i 6DE 1.

ace mo e swj chin e

shutdo pos'(ion.

me 'atel BFN-UNIT3 3A-2 Amendment No. 216 December 23, 1998

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'SURVEILLANCEREQUIREMENTS SURVEILLANCE Recirculation Loops Operating 3.4.1 FREQUENCY SR 3.4.1.1

-NOTE-Not required to be performed until 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after both recirculation loops are in operation.

Verify recirculation loop jet pump flow mismatch with both recirculation loops in operation is:

24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />

a. s 10% of rated core flowwhen operating at ( 70% of rated core flow; and

b. i5% of rated core flow when operating at z 70% of rated core flow.

S 3.4.1.2 V ifyther actoris Ctsideof gioniandii f Figure

.4.1-1.

mmediately after any increase

) 5% RTP wP e initial core Iow is (50% of ated AND mediately fter any deere e of

) 10% r ed core floww ile initial ther al poweri

) 4 % of rate BFN-UNIT3 3.4-3 Amendment No. 213 September 03, 1998

Recirculation Loops Operating 3.4.1 FN power low Stabili Regions

)teoton I

Reolon II Une 0NRod Une 70.00 So.

te ee I

eo.oo In

$0.00 Nole'tetl on N

(ted ln e Retfon Rod U 2'h Rod

.00 Ctr lotion 10.00 40 50 5560 0

S 10 IS 20 5

ore Flow r% of rated) 6S 70 7$

60 6S 00 0S 100 Fi ure 3.4.1-1 PglW V

SU OR LO STA IT+AEGIO (g aZ < ac~ rS ega)

BFN-UNIT3 3.4-4 Amendment No. 214 September 08, 1998

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RPS Instrumentation B 3.3.1.1 BASES APPLICABLE SAFETYANALYSES, LCO, and APPLICABILITY (continued)

Avera e Power Ran e Monitor The APRM channels provide the primary indication of neutron fluxwithin the core and respond almost instantaneously to neutron flux increases.

The APRM channels receive input signals from the local power range monitors (LPRMs) within the reactor core to provide an indication of the power distribution

'nd local power changes.

The APRM channels average these LPRM signals to provide a continuous indication of aver e

reactor power from a few percent to greater than RTP. Ense~+ b 7 s+

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~~ ZiC The APRM System is divided into four APRM channels and four 2-out-of-4 voter channels.

Each APRM channel provides inputs to each of the four voter channels.

The four voter channels are divided into two groups of two each, with each group of two providing inputs to one RPS trip system.

The system is designed to allow one APRM channel, but no voter channels, to be bypassed.

A trip from any one unbypassed APRM willresult in a "half-tri " in all four of the voter channels, but no trip inputs to either RPS trip system.

ffttrip from any two unbypassed APRM channels willresult in a fulltrip in each of the four voter channels, which in turn results in two tri in uts to each RPS np system logic channel (A1, A2, B1, or B2). Three of the four APRM channels and all four of the voter channels are required to be OPERABLE to ensure that no single failure willpreclude a scram on a valid signaI.

In addition, to provide adequate cover'age of thepntire core, consistent with the design bases'or the APRMfunctions, at least twenty (20) LPRM inputs, with at east three M inputs from each of the four axial levels at which the LPRMs are located, must be operable for each APRM channel.

continued BFN-UNIT3 B 3,3-9 Amendment No. 213 September 03, 1998

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Each APRM also includes an Oscillation Power Range Monitor (OPRM) Upscale Function which monitors small groups ofLPRM signals to detect thermal-hydraulic instabilities.

INSERT K APRM trip Functions 2.a, 2.b, 2.c and 2.d are voted independently from OPRM Upscale Function 2.f. Therefore, any Function 2.a, 2.b, 2.c, or 2.d INSERT F Similarly, a Function 2.ftrip from any two unbypassed APRM channels willresult in a full trip from each ofthe four voter channels.

INSERT G For the OPRM Upscale Function 2.f, LPRMs are assigned to "cells" with either 3 or 4 detectors, with a total of33 "cells" assigned to each OPRM channel. A minimum of23 cells, each with a minimum of2 LPRMs must be OPERABLE for the OPRM Upscale Function 2.fto be OPERABLE.

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RPS Instrumentation B 3.3.1.1 I

, BASES APPLICABLE SAFETYANALYSES, LCO, and APPLICABILITY (continued) 2.d. Avera e Power Ran e Monitor - Ino Three of the four APRM channels are required to be OPERABLE for each of the APRM Functions.

This Function (Inop) provides assurance that the minimum number of APRMs are OPERABLE. For any APRM channel, any time its mode switch is in any position other than "Operate," an APRM module is unplugged, or the automatic self-test system detects a critical fault with the APRM channel, an Inop tri is sent to all four voter channels.

Inop trips from two or mor

- ypassed APRM channels result in a trip output from all four voter channels to their associated trip system.

This Function was not specifically credited in the accident analysis, but it is retained for the overall redundancy and diversity of the RPS as required by the NRC approved licensing basis.

There is no Allowable Value for this Function.

This Function is required to be OPERABLE in the MODES where the APRM Functions are required.

continued BFN-UNIT3 B 3.3-14 Amendment No. 21 3 September 03, 1998

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BASES RPS Instrumentation B 3.3.1.1 APPLICABLE SAFETYANALYSES, LCO, and APPLICABILITY (continued)

nc/~ding

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2.e. 2-Out-Of-4 Voter The 2-Out-Of-4 Voter unction provides the interface between the APRM Function and the final RPS trip system logic. As such, it is required to be OPERABLE in the MODES where the'PRM Functions are required and is necessary to support the safety analysis applicable to each of those Functions.

Therefore, the 2-Out-Of-4 Voter Function needs to be OPERABLE in MODES 1 and 2.

Allfour voter channels are required to be OPERABLE. Each voter channel includes self-diagnostic functions.

Ifany voter channel detects a critical fault in its own processing, a trip is issued from that voter channel to the associated trip system.

~nyet There is no Allowable Value for this Function.

0 BFN-UNIT3 B 3.3-15 continued Amendment No. 213 September 03, 1998

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The 2-Out-Of-4 Voter Function votes APRM Functions 2.a, 2.b, 2.c, and 2.d independently ofFunction 2.f. The voter also includes separate outputs to RPS for the two independently voted sets ofFunctions, each ofwhich is redundant (four total outputs).

The voter Function 2.e must be declared inoperable ifany ofits functionality is inoperable.

However, due to the independent voting ofAPRM trips, and the redundancy ofoutputs, there may be conditions where the voter Function 2.e is inoperable, but trip capability for one or more ofthe other APRM Functions through that voter is still maintained.

This may be considered when determining the condition ofother APRM Functions resulting from partial inoperability ofthe Voter Function 2.e.

INSERT I 2.f. Oscillation Power Ran e Monitor OP U scale The OPRM Upscale Function provides compliance with GDC 10 and GDC 12, thereby providing protection from exceeding the fuel MCPR safety limit(SL) due to anticipated thermal-hydraulic power oscillations.

References 13, 14 and 15 describe three algorithms for detecting thermal-hydraulic instability related neutron flux oscillations: the period based detection algorithm, the amplitude based algorithm, and the growth rate algorithm. Allthree are implemented in the OPRM Upscale Function, but the safety analysis takes credit only for the period based detection algorithm. The remaining algorithms provide defense in depth and additional protection against unanticipated oscillations.

OPRM Upscale Function OPERABILITY for Technical Specification purposes is based only on the period based detection algorithm.

The OPRM Upscale Function receives input signals from the local power range monitors (LPRMs) within the reactor core, which are combined into "cells" for evaluation ofthe OPRM algorithms.

The OPRM Upscale Function is required to be OPERABLE when the plant is in a region ofpower-flow operation where anticipated events could lead to thermal-hydraulic instability and related neutron flux oscillations. Withinthis region, the automatic trip is enabled when THERMALPOWER, as indicated by the APRM Simulated Thermal Power, is 2 25% RTP and reactor core flow, as indicated by recirculation drive flow is < 60% of rated flow, the operating region where actual thermal-hydraulic oscillations may occur.

Requiring the OPRM Upscale Function to be OPERABLE in Mode 1 provides consistency with operability requirements for other APRM functions and assures that the OPRM Upscale Function is OPERABLE whenever reactor power could increase into the region ofconcern without operator action.

An OPRM Upscale trip is issued from an APRM channel when the period based detection algorithm in that channel detects oscillatory changes in the neutron flux, indicted by the combined signals ofthe LPRM detectors in a cell, with period confirmations and relative cell amplitude exceeding specified setpoints.

One or more cells in a channel exceeding the trip conditions willresult in a channel trip. An OPRM Upscale trip is also issued from the channel ifeither the growth rate or amplitude based algorithms detect growing oscillatory changes in the neutron fluxfor one or more cells in that channel.

Three ofthe four channels are required to be OPERABLE. Each channel is capable of detecting thermal-hydraulic instabilities, by detecting the related neutron flux oscillations, and issuing a trip signal before the MCPR SL is exceeded.

There is no allowable value for this function.

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'BASES RPS Instrumentation B 3.3.1.1 ACTIONS (continued)

A.1 and A.2 Because of the diversity of sensors available to provide trip

'ignals and the redundancy of the RPS design, an allowable out of service time of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> has been shown to be acceptable (Ref. 9 and 12) to permit restoration of any I

inoperable channel to OPERABLE status.

However, this out of service time is only acceptable provided the associated Function's inoperable channel is in one trip system and the Function still maintains RPS trip capability (refer to Required Actions B.1, 8.2, and C.1 Bases).

Ifthe inoperable channel cannot be restored to OPERABLE status within the allowable out of service time, the channel or the associated trip system must be placed in the tripped condition per Required Actions A.1 and A.2. Placing the inoperable channel in trip (or the associated trip system in trip) would conservatively compensate for the inoperability, restore capability to accommodate a single failure, and allow operation to continue.

Alternatively, ifit is not desired to place the channel (or trip system) in trip (e.g., as in the'case where placing the inoperable channel in trip would result in a full scram),

Condition D must be ed and its Required Action taken.

]o~ 2.f As noted Action is not applicable for APRM Functions 2.a, 2.b, 2.c, 2.d Inoperability of one required APRM channel affects both trip systems.

For that condition, Required Action A.1 must be satisfied, and is the only action (other than restoring operability) that will restore capability to accommodate a single failure.

Inoperability of more than one required APRIVI channel of the same trip function results in loss of trip capability and entry into Condition C, as well as entry into Condition Afor each channel.

continued BFN-UNIT3 B 3.3-30 Amendment No. 213 September 03, 1998

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RPS Instrumentation B 3.3.1.1

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. BASES ACTIONS 8.1 and B.2 (continued)

The 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> Completion Time is judged acceptable based on the remaining capability to trip, the diversity of the sensors available to provide the trip signals, the low probability. of extensive numbers of inoperabilities affecting all diverse Functions, and the low probability of an event requiring the initiation of a scram.

A. ALt.net'ton 'tn Fg.ff,f'+'fO Alternatel, ifit is not desired to place the inoperable channels (or one trip system) in trip (e.g., as in the case where placing the inoperable channel or associated trip system in trip would result in a scram or RPT), Condition D must be entered and its Required Action taken.

As noted, Condition B is not applicable for APRM Functions 2.a, 2.b, 2.c,(ti92.d tnoperabitity of an APRM channel affects both trip systems and is not associated with a specific trip system as are the APRM 2-out-of-4 voter and other non-APRM channels for which Condition B applies.

For an inoperable APRM channel, Required Action A.1 must be satisfied, and is the only action (other than restoring operability) that willrestore capability to accommodate a single failure. Inoperability of more than one required APRM channel results in loss of trip capability and entry into Condition C, as well as entry into Con i ion Aforeach channel.

Because Conditions A and C provide Required Actions that are appropriate for the Or 2.

inoperability of APRM Functions 2.a, 2.b, 2.c,

.d, and these functions are not associated with specific trip systems as are the APRM 2-out-of-4 voter and other non-APRM channels, Condition B does not apply.

continued BFN-UNIT3 B 3.3-32 Amendment No. 213 September 03, 1998

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'BASES RPS Instrumentation B 3.3.1.1 ACTIONS (continued)

D.1 Required Action D.1 directs entry into the appropriate Condition referenced in Table 3.3.1.1-1.

The applicable Condition specified in the Table is Function and MODE or other specified condition dependent and may change as the Required Action of a previous Condition is completed.

Each time an inoperable channel has not met any Required Action of Condition A, B, or C and the associated Completion Time has expired, Condition D will be entered for that channel and provides for transfer to the appropriate subsequent Condition.

E.1 F.1 G.1 Ifthe channel(s) is not restored to OPERABLE status or placed in trip (or the associated trip system placed in trip) within the allowed Completion Time, the plant must be placed in a MODE or other specified condition in which the LCO does not apply.

The allowed Completion Times are reasonable, based on operating experience, to reach the specified condition from full power conditions in an orderly manner and without challenging plant systems.

In addition, the Completion Time of Required Action E.1 is consistent with the Completion Time provided in LCO 3.2.2, "MINIMUMCRITICALPOWER RATIO (MCPR)."

continued BFN-UNIT3 B 3.3-34 Amendment No. 213 September 03, 1998

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RPS Instrumentation B 3.3.1.1 BASES ACTIONS (continued) onself 4 3

Ifthe channel(s) is not restored to OPERABLE status or placed in trip (or the associated trip system placed in trip) within the allowed Completion Time, the plant must be placed in a MODE or other specified condition in which the LCO does not apply.

This is done by immediately initiating action to fully insert all insertable control rods in core cells containing one or more fuel assemblies.

Control rods in core cells containing no fuel assemblies do not affect the reactivity of the core and are, therefore, not required to be inserted.

Action must continue until all insertable control rods in core cells containing one or more fuel assemblies are fullyinserted.

SURVEILLANCE As noted at the beginning of the SRs, the SRs for each RPS REQUIREMENTS instrumentation Function are located in the SRs column of Table 3.3.1.1-1.

The Surveillances are modified by a Note to indicate that when a channel is placed in an inoperable status solely for performance of required Surveillances, entry into associated Conditions and Required Actions may be delayed for up to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, provided the associated Function maintains RPS trip capability.

Upon completion of the Surveillance, or expiration of the 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> allowance, the channel must be returned to OPERABLE status or the applicable Condition entered and Required Actions taken. This Note is based on the reliability analysis (Ref. 3) assumption of the average time required to perform channel Surveillance.

That analysis demonstrated that the 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> testing allowance does not significantly reduce the probability that the RPS willtrip when necessary.

continued BFN-UNIT3 B 3.3-35 Revision 0

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INSKRYJ IfOPRM Upscale trip capability is not maintained, Condition I exists.

Reference 12 justified use ofalternate methods to detect and suppress oscillations for a limited period of time. The alternate methods are procedurally established consistent with the guidelines identified in Reference 17 requiring manual operator action to scram the plant ifcertain predefined events occur. The 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> allowed action time is based on engineering judgment to allow orderly transition to the alternate methods while limitingthe period of time during which no automatic or alternate detect and suppress trip capability is formally in place.

Based on the small probability ofan instability event occurring at all, the 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is judged to be reasonable.

I,2 The alternate method to detect and suppress oscillations implemented in accordance with I.l was evaluated (Reference 12) based on use up to 120 days only. The evaluation, based on engineering judgment, concluded that the likelihood ofan instability event that could not be adequately handled by the alternate methods during this 120 day period was negligibly small. The 120 day period is intended to be an outside limitto allow for the case where design changes or extensive analysis might be required to understand or correct some unanticipated characteristic ofthe instability detection algorithms or equipment. This action is not intended and was not evaluated as a routine alternative to returning failed or inoperable equipment to OPERABLE status.

Correction ofroutine equipment failure or inoperability is expected to normally be accomplished within the completion times allowed for Actions for Conditions A and B.

yl RPS Instrumentation B 3.3.1.1 BASES SURVEILLANCE REQUIREMENTS (continued)

SR 3.3.1.1.11 (Deleted) 4 SR 3.3.1.1.14 an+ oPP-W The LOGIC SYSTEM FUNCTIONALTEST demonstrates the OPERABILITYof the required trip logic for a specific channel.

The functional testing of control rods (LCO 3.1.3), and SDV vent and drain valves (LCO 3.1.8), overlaps this Surveillance to provide complete testing of the assumed safety function.

f The 24 month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage and the potential for an unplanned transient ifthe Surveillance were performed with the reactor at power.

Operating experience with these components supports performance of the Surveillance at the 24 month Frequency.

The LOGIC SYSTEM FUNCTIONALTEST forAPRM Function 2.e simulates APRM trip conditions at the 2-out-of-4 voter channel inputs to check all combinations of two tripped inputs to the 2-out-of-4 logic in the voter channels and APRM related redundant RPS relays.'ontinued BFN-UNIT3 B 3.3-44 Amendment No. 215 November 30, 1998

~ g

RP S Instrumentation B 3.3.1.1 SURVEILLANCE REQUIREMENTS (continued)

SR 3.3.1.1.15 This SR ensures that scrams initiated from the Turbine Stop Valve - Closure and Turbine Control Valve Fast Closure, Trip Oil Pressure - Low Functions willnot be inadvertently,,

bypassed when THERMALPOWER is a 30% RTP. This involves calibration of the bypass channels (PIS-1-81A, PIS-1-81B, PIS-1-91A, and PIS-1-91 B). Adequate margins for the instrument setpoint methodologies are incorporated into the actual setpoint.

lfany bypass channel's setpoint is nonconservative (i.e., the Functions are bypassed at a 30% RTP, either due to open main turbine bypass valve(s) or other reasons), then the affected Turbine Stop Valve - Closure and Turbine Control Valve Fast Closure, Trip Oil Pressure - Low Functions are considered-inoperable.

Alternatively, the bypass channel can be placed in the conservative condition (nonbypass).

Ifplaced in the nonbypass condition (Turbine Stop Valve - Closure and Turbine Control Valve Fast Closure, Trip Oil Pressure

- Low Functions are enabled), this SR is met and the channel is considered OPERABLE.

The Frequency of 24 months is based upon the assumption of a 24 month calibration interval in the determination of the magnitude of equipment drift in the setpoint analysis.

(continued)

BFN-UNIT3 B 3.3-45 Amendment No. 215 November 30, 1998

This SR ensures that scrams initiated from OPRM Upscale Function (Function 2.f) will not be inadvertently bypassed when THERMALPOWER, as indicted by the APRM Simulated Thermal Power, is 2 25% RTP and core flow, as indicted by recirculation drive flow, is < 60% rated core flow. This normally involves confirming the bypass setpoints.

Adequate margins for the instrument setpoint methodologies are incorporated into the actual setpoint.

The actual surveillance ensures that the OPRM Upscale Function is enabled (not bypassed) for the correct values ofAPRM Simulated Thermal Power and recirculation drive flow. Other surveillances ensure that the APRM Simulated Thermal Power and recirculation flowproperly correlate with THERMALPOWER and core flow respectively.

Ifany bypass setpoint is nonconservative (i.e., the OPRM Upscale Function is bypassed when APRM Simulated Thermal Power 2 25% RTP and recirculation drive flow< 60%

rated), then the afFected channel is considered inoperable for the OPRM Upscale Function.

Alternatively, the bypass setpoint may be adjusted to place the channel in a conservative condition (unbypass). Ifplaced in the unbypassed condition, this SR is met and the channel is considered OPERABLE.

The frequency of24 months is based on engineering judgment and reliabilityofthe components.

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RPS Instrumentation 8 3.3.1.1

~

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BASES (continued)

REFERENCES ngcM FSAR, Section 7.2.

2.

FSAR, Chapter 14.

3.

NEDO-23842, "Continuous Control Rod Withdrawal in the Startup Range," April 18, 1978.

4.

FSAR, Appendix N.

5.

FSAR, Section 14.6.2.

6.

FSAR, Section 6.5.

7.

FSAR, Section 14.5.

8.

P. Check (NRC) letter to G. Lainas (NRC), "BWR Scram Discharge System Safety Evaluation," December 1, 1980.

9.

NEDC-30851-P-A, "Technical Specification Improvement Analyses for BWR Reactor Protection System,"

March 1988.

10.

NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

11.

MED-32-0286, 'Technical Specification Improvement Analysis for Browns Ferry Nuclear Plant, Unit 2," October 1995.

12.

NEDC'-3241 OP-A, "Nuclear Measurement Analysis and Control Power Range Neutron Monitor (NUMAC PRNM)

Retrofit Plus Option IIIStability Trip Function," October 1995.

BFN-UNIT3 B 3.3Q6 Amendment No. 213 September 03, 1998

INSERT L 13.

NEDO-31960-A, "BWROwners'roup Long-Term Stability Solutions Licensing Methodology," November 1995.

14.

NEDO-31960-A, Supplement 1, "BWROwners'roup Long-Term Stability Solutions Licensing Methodology," November 1995.

15.

NEDO-32465-A, "BWROwners'roup Long-Term Stability Detect and Suppress Solutions Licensing Basis Methodology and Reload Applications," August 1996.

16.

NEDC-32410P-A, Supplement 1, "Nuclear Measurement Analysis and Control Power Range Neutron Monitor (NUMAC.PRNM) Retrofit Plus Option III Stability Trip Function," August 1996.

17.

Letter, L.A. England (BWROG) to M.J. Virgilio,"BWROwners'roup Guidelines for Stability Interim Corrective Action," June 6, 1994.

Recirculation Loops Operating 8 3.4.1 BASES 0:

APPLICABLE SAFETYANA (continued)

Plant specific LOCA analyses have been performed assuming LYSES only one operating recirculation loop. These analyses have demonstrated that, in the event of a LOCA caused by a pipe break in the operating recirculation loop, the Emergency Core Cooling System response willprovide adequate core cooling, provided the APLHGR requirements are modified accordingly (Refs. 7 and 8).

The transient analyses of Chapter 14 of the FSAR have also been performed for single recirculation loop operation (Ref. 7) and demonstrate sufficient flowcoastdown characteristics to maintain fuel thermal margins during the abnormal operational transients analyzed provided the MCPR requirements are modified. During single recirculation loop operation, modification to the Reactor Protection System (RPS) average power range monitor (APRM) instrument setpoint is also I

required to account for the different relationships between recirculation drive flowand reactor core flow. The APLHGR and MCPR setpoints for single loop operation are specified in the COLR. The APRM Flow Biased Simulated Thermal Power-High setpoint is in LCO 3.3.1.1, "Reactor Protection System (RPS) Instrumentation.

Saf tyanaP seep rforme for FS R+apter 4impl'tly sume~re cghdition are st e.+owev r, at t high

. owerglowfl &corn of the owpFNow ap, agi crease pro 6bili orlimi cycle9 cill tlonse sts(R f.3) dept ding o

corn inatio ofoperstin condii ns(e,powerphape, un/I powe,andbghdle ow).

eneri evaluatigKsindicat th twhen~ giontfVpowft oscilpl iona tt corned tectableo the operpftng conditions'to enydre act'dns take to respo d to the A %Ms sigitals 6utd prp9ent v'tion oP he MCP Safety imit(graf.4),

RC G heric tter86 2(Ref. 5 address d

stab)iiiycalp lation ethod ogyan stated ttt tdueto un rtainles,10 R50 pen i A, Ge Eral Desi Criter continued BFN-UNIT3 B 34-4 Revision 3 March 19, 1999

JI

'BASES Recirculation Loops Operating B 3.4.1 APPLICABLE SAFETYANALYSES (continued)

(GDC) 10 a 12 could ot be met u ng analytic proc ures on a BWR4 esign.

Ho ever, Refer ce5concludedg at operatic limitation hich prov' for the detecti n (by monitpl'ing neutro flux noise j vels) and supp ssion of flux osc)ilations in o crating reg'6ns of potential 'tability c insistent wit the recom endations of ference 3 are cceptable demonstr e compliance ith GDC 10 and 2.

The NRC oncluded t at regions of p tential instabilit could occur a alculated P cay ratios of

.8 or greater by e General Electr'ethodology.

Sty ilitytests y operating B Rs were revie ed to determine generic regi 6 of the pow

/flow map in wP ch surveillancey eutron flu noise level should be perf fmed. A consery4tive decay rafio was chose as the basis r determining tgdgeneric region 6r surveilla Ee to account f the plant to plyrft varia ilityof dec ratio with cor and fuel desigriK This decay rati also helps nsure sufficing t margin to an 'trustability o currence i

aintained.

e generic reg' has been etermine o be bounde by the 76.2%

d line and the 4

/o core flow ine. BFN co ervatively imp ements this gen ic region ith the "Ope tion Not Permitted" Region an egions I

and of Figure 3..1-1. This copforms to Refere e 3 re mmendatio

. Operation 'unpermitted in gion II provide eutron flux n ise levels ar erified to bey'n limits. Th reactor mo switch mus e placed in tPEshutdown po i ion (an imme iate scram is equired) if R pion I is entere Recirculation loops operating satisfies Criterion 2 of the NRC Policy Statement (Ref. 6).

(continued)

BFN-UNIT3 B 3.4-5 Amendment No. 216 December 23, 1998

4a

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~ A Recirculation Loops Operating B 3.4.1 LCO Two recirculation loops are required to be in operation with their flows matched within the limits specified in SR 3.4.1.1 to ensure that during a LOCA caused by a break of the piping of one recirculation loop the assumptions of the LOCA analysis are satisfied.

With the limits specified in SR 3.4.1.1 not met, the recirculation loop with the lower flowmust be considered not in operation.

With only one recirculation loop in operation, modifications to the required APLHGR Limits (LCO 3.2.1, "AVERAGEPLANARLINEARHEAT GENERATION RATE (APLHGR)'), MCPR limits (LCO 3.2.2, 'MINIMUMCRITICAL POWER RATIO (MCPR)"), and APRM Flow Biased Simulated Thermal Power-High Setpoint (LCO 3.3.1.1) may be applied to allow continued operation co siste pt'eferences7and8 J

g di on cor fig e

re se as f

in f E

CP~O tb oukide eio I

n I

n th Oer i

t'Pp ied ein fFiur 3..1-.

APPLICABILITY In MODES 1 and 2, requirements for operation of the Reactor Coolant Recirculation System are necessary since there is considerable energy in the reactor core and the limitingdesign basis transients and accidents are assumed to occur.

In MODES 3, 4, and 5, the consequences of an accident are reduced and the coastdown characteristics of the recirculation loops are not important.

(continued)

BFN-UNIT3 B 3.4-5a Amendment No. 216 December 23, 1998

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'ASES (continued)

Recirculation Loops Operating B 3.4.1 ACTIONS A.1 The mini m margin to t onset of thy mal hydraulic in ability occurs en the plant i in Region I f'Figure 3.4.1-1.

There) re, the reactor ode switch 's required to be laced in theyhutdown positi n upon entry nto this region.g his action is c 6sidered suffic't to preclud core oscillatio 6 which could allenge the PR safety li it.

B.1 and B Imme ate action is quired to exi egion II of Figur 3.4.1-1 upo entry by con ol rod inserti or flow increas The 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> C

pletion Tim for exiting th region is acceptable because it inimizes the sk while allo ing time to exit ted region without challenging ant systems Because the pr t5ability of therm hydraulic cillations is) wer and the ma in to the MCPR safety li it is greaterjrf Region II than i Region I, placin the mode witch in the hutdown positio pon entry into t region is n necessary.

he mode switch ust be placed i

he s

tdown posi ifevidence of ermal hydraulicj stability is bserved.

F mal surveillance are not perform Cf while exiting Region IIs'e delaying exit r surveillance is ndesirable.

One o ore of the folio ng conditions is n indication of reac r instability indu d power oscilla 'ons when opera in or ear the identifie regions:

continued BFN-UNIT3 B 3.4-6 Revision 0

E

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Recirculation Loops Operating B 3.4.1 BASES ACTIONS B.

and

.2 (co tinued ustai din asein PRMan or LP peak o-pea ignai oisept ei, re ing two r mor imes it initial/ vel atry ucedyorefio conditio

. Any oticea le incr use in n (se Iev (warra s closer onitor' of th PR ignals.

The i crease noise o rs wi a char eristi period les than3 econds.

2.

PRMy dorAP Mups leandl rdo cate annu aviators t t ala ith a aracte stic p tod of I s

tha secon s.

A,Z With the requirements of the LCO not met, the recirculation loops must be restored to operation with matched flows within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. A recirculation loop is considered not in operation when the pump in that loop is idle or when the mismatch between total jet pump flows of the two loops is greater than required limits. The loop with the lower flowmust be considered not in operation.

Should a LOCA occur with one recirculation loop not in operation, the core flowcoastdown and resultant core response may not be bounded by the LOCA analyses.

Therefore, only a limited time is allowed to restore the inoperable loop to operating status.

Alternatively, ifthe single loop requirements of the LCO are applied to the operating limits and RPS setpoints, operation with only one recirculation loop would satisf'y the requirements of the LCO and the initial conditions of the accident sequence.

continued BFN-UNIT3 8 3.4-7 Amendment No. 216 December 23, 1998

h

Recirculation Loops Operating 3.4.1

<< i BASES AGTlONS (continued)

The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Time is based on the low probability of an accident occurring during this time period, on a reasonable time to complete the Required Action, and on frequent core monitoring by operators allowing abrupt changes in core fiow'onditions to be quickly detected.

This Required Action does not require tripping the recirculation pump in the lowest fiowloop when the mismatch between total jet pump flows of the two loops is greater than the required limits. However, in cases where large fiowmismatches occur, low flowor reverse fiowcan occur in the lowflowloop jet pumps, causing vibration of the jet pumps.

Ifzero or reverse fiowis detected, the condition should be alleviated by changing pump speeds to re-establish forward flowor by tripping the pump.

PfooES I or With no recirculation loops in operation white in

~

2 or the Re uired Action and associated Completion Time o Condition r

not met, the plant must be brought to a MODE in which the LCO does not apply. To achieve this status, the plant must be brought to MODE 3 within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.

In this condition, the recirculation loops are not required to be operating because of the reduced severity of DBAs and minimal dependence on the recirculation loop coastdown characteristics.

The allowed Completion Time of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> is reasonable, based on operating experience, to reach MODE 3 from full power conditions in an orderly manner and without challenging plant systems.

continued BFN-UNIT3 B 3A-8 Amendment No. 216 December 23, 1998

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BASES Recirculation Loops Operating B 3.4.1 ACTIONS (continued)

Wi therea orinM DE1an noreci ulatio pum s o crating, ereact modes itchmu tbep cedi the hutdow position mmedia ly. Ani medi escr mis require since B N does ot have ectiv auto atic sc m

prote ionforr gional o cillations This quire entw s mented o compl with Ref ence SURVEILLANCE REQUIREMENTS SR 3.4.1.1 This SR ensures the recirculation loops are within the allowable limits for mismatch.

At low core flow (i.e., < 70% of rated core flow), the MCPR requirements provide larger margins to the fuel cladding integrity Safety Limitsuch that the potential adverse effect of early boiling transition during a LOCA is reduced.

A larger flow mismatch can therefore be allowed when core flow is

< 70% of rated core flow. The recirculation loop jet pump flow, as used in this Surveillance, is the summation of the flows from all of the jet pumps associated with a single recirculation loop.

The mismatch is measured in terms of percent of rated core flow. Ifthe flow mismatch exceeds the specified limits, the loop with the lower flow is considered inoperable.

The SR is not required when both loops are not in operation since the mismatch limits are meaningless during single loop or natural circulation operation.

The Surveillance must be performed within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> after both loops are in operation.

The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Frequency is consistent with the Surveillance Frequency forjet pump OPERABILITYverification and has been shown by operating experience to be adequate to detect off normal jet pump loop flows in a timely manner.

continued BFN-UNIT3 B 3.4-9 Revision 0

4 4',

<jl

Recirculation Loops Operating B 3.4.1

~ 'i BASES SURVEILLANCE REQUIREMENTS (continued)

SR

.4.1.2 his S ensur s the reacg r THER L POWE nd core f are thinag ropriatepdrametergi itstoprev tuncontr led po er osc Ibations.

Plow reciryCilation flow and high actor p wer, t ereactor xhibitsi Ereasedsus eptibilityt thermal ydray ic instabjII y. Figur 3.4.1-1 is sed on dance provj6ed in Reference 3 which is us d to resp' to ope tion in heseco 8itions.

P rformance'ediate faftera

'rease f more t n 5% RTP ile initi core flo s (50%

of rate and im diately afte any deer se of my e than 10/

rate core flo hile initial ermal p er is ) 46% of rate s

a quate to etect pow oscittatio s that c did lead to ermat ydraulic 'tability.

REFERENCES 1.

FSAR, Section 14.6.3.

2.

FSAR, Section 4.3.5.

3.

GE rvice nform ion Le er No.

0, "B RCor Th rmal draul'tabili," Revi ion 1, ebrua 10, 1

84.

4.

NRC ulleti 8-07," ower g cillatio s in Bo'ing Waf r Re tors(

Rs),"

upple hnt1, D cember 0,19 8.

C Ge ericLe er86-0, "Techn al Res lution eneri Issue

-19, Th mal Hyd aulic St bility,"

Janua 22, 1

86.

6.

NRC No.93-102, "Final Policy Statement on Technical Specification Improvements," July 23, 1993.

7.

NEDO-24236, "Browns Ferry Nuclear Plant Units 1, 2, and 3, Single-Loop Operation," May 1981.

8.

NEDC-32484P, "Browns Ferry Nuclear Plant Units 1, 2, and 3, SAFER/GESTR-LOCA Loss-of-Coolant Accident Analysis," Revision 2, December 1997.

BFN-UNIT3 B 3.4-10 Amendment No. 216 December 23, 1998

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