ML18029A585

Proposed Tech Specs Re Reactor Protection Sys

ML18029A585
Person / Time
Site:	Browns Ferry
Issue date:	06/06/1985
From:	TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML18029A584	List: ML18029A583 ML18029A585
References
NUDOCS 8506190244
Download: ML18029A585 (20)

Text

ENCLOSURE 1 PROPOSED TECHNICAL SPECIFICATION REVISIONS BROWNS FERRY NUCLEAR PLANT UNITS 1, 2, AND 3 (TVA BFNP TS 200 SUPPLEMENT 1)

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~ 0 PROPOSED UNIT 1 TECHNICAL SPECIFICATION REVISIONS

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LIMITING CONDITIONS FOR OPERATION SURVEXILANCE klPUIREHENTS 3.1 REACTOR PROTECTION SYSTEM 4el REACTOR PROTECTION SYSTEM A licabilit ~A 11c~ettlt t Applies to the instrumentation Applies to the surveillance of and associated devices which the instrumentation nnd asso-initiate a reactor scram. ciated devices which initiate reactor scram.

~0b ecetve ~0b ective To assure the operability of the To specify the type and frequency reactor protection system. of surveillance to be applied to the protection instrumentation.

S ecification S ecification When ther'e is fuel in the vessel, A. Instrumentation systems shall the setpoints, minimum number of be functionally tested and trip systems, and minimum number calibrated as indicated in of instrument channels that must Tables 4.1.A and 4.1.9 respec-be operable for each position of tively.

the reactor mode a~itch shall be as given in Table 3.1.A.

B. Twn RPS power monitoring channels fnr each inscrvice'PS flG sets or alternate sour' shall bu ceper'able.

1. With one RPS electric pnwer monitoring channel for inservice RPS MG set or alternate power supply inoperable, restore the inoperable channel to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> nr remove the associated RPS MG set or alternate power supply from service.

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'I NOTES FOR TABLE 3.1.A

1. There shall be two operable or tripped trip systems for each function. If the minimum number of operable instrument channels per trip system cannot be met for one trip system trip the inoperable channels or entire trip system within one hour, or, alternatively, take the below listed action for that trip function.

If the minimum number of operable instrument channels cannot be met by either trip system, the appropriate action listed below (refer to right-hand column nf Table) sliall be taken. An inoperable cliannel pepd not be placed in the tripped condition where this would cause php trip function to occur. In these cases, the inoperable channel sliall be restored to operable status within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, or take the action listed below for. that trip function.

A. Initiate insertion of operable rods and complete insertion of all operable rods within four hours.

In refueling mode, suspend all operations involvinp core alterations and fully insert all operable control rods

~~ithin one hnut.

B. Reduce power level to ZRN range and place mode switch in the'Startup/Hot Standby position within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

C ~ Reduce turbine load and close main steam line isolation valves within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

D. Reduc power to less than 30$ of rated.

2. Scram discharqe volume high bypass may be used in shutdown or refuel to bypass scram discharge volume scram with control rod block for reactor protection system reset.

3. Bypassed 'if reactor pressure < 1055 psig and mode switch not in run.

4. Bypassed when turbine first stage pressure is less than 154 p iq

5. IRx's are bypassed when APRH'o are onocalo and the reactor switch io in the run position. 'ode

6. The desiqn permits cloouro of any two linea without a scram be ing ini ti at cd.

when the reactor is subcritical and the reactor water tenp rature is less than 212 F, only the following trip function" need to be operable:

t A. Node switch in shutdown B. Hanual scram C. High flux IRH D. Scram discharge volume high level E. APRN 15% scram

8. trot required to he operablo when primary containment integrity is not required.

9. Hot required if all main stoamlinea are isolated.

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PROPOSED UNIT 2 TECHNICAL SPECIFICATION REVISIONS UNITING C05IDXTIONS FOR OPERATION SURVEILLkiCE RE UIRE29'.NTS 3.1 REACTOR PR TECTION SYSTEM 4~1 REACTOR PROTECTIOiV SYSTEM

~Al~icatlllt App1ies to the instrumentation Applies to the surveillance of and associated devices which the instrumentation and asso-initiate a reactor scram. ciated devices which initiate reactor scram

~at ectf.va Ob ective To assure the operability of the To pecify the type and frequency reactor protection system. of surveillance to be applied to tne protection instrumentation.

S ecification ."necl f lean lan N<en there is fuel in the ves"el, the setpoints, minimum number of A. Inutrume>>t:it I>>n Syati.ill 'ah ~ lit be functionally tc::ted <<nd trip systems, and minimum number calibrated as indicated'in of instrument channels that must Tables 4al.h and 4.1.8 respec-be operable for each position of tively.

the reactor mode switch shall be as given in Table 3.1.A.

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0 NOTES FOR TABLE 3. 1.A 1'. There shall be two operable or tripped trip systems for each function. If the minimum number of operable instrument channels per trip system cannot be met for one trip system trip the inoperablechannels or entire trip system within one hour, or, alternatively, take the below listed action for that trip function.

If the minimum number of operable instrument channels cannot be met by either trip system, the appropriate action listed below (refer to jight-Pand column of Table) shall be taken. An inoperable channel need not be placed in the tripped condition where this would cause the trip function to occur. In these cases, the inoperable channel shall be restored to operable status within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, or take the action listed below for that trip function.

A. Initiate insertion of operable rods and complete insertion of all operable rods within four hours.

In refueling node, suspend all operations involvinp core alterations and fully insert all operable contxol rods wit? in nne hoot.

B. Reduce power level to XRM range and place mode switch in the Startup/Hot Standby position within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

C. Reduce turbine load and close main steam line isolation valves ~ithin 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

D. Reduce power to less than 30% of rated.

2. Scram discharqe,volume high bypass may be used in shutdown or refuel to.bypass scram discharge volume scram with control rod block for reactor protection system reoet.

3. Bypaosed if reactor preosure < 1055 psig and mode switch not in run.

4. Bypassed when turbin first otage pressure io less than 154 pslqo

5. IRM's are bypassed when APRM'o are onocale and the reactor "

mode switch io in the run position.

6. The deoiqn permits cloouro of any two lineo without a scram be ing ini tiat ed.

7. when the reactor is oubcritical and the reactor water temperature io less than 212~F, only the following trip tunction" need to be operable:

A. Mode switch in shutdown B. Manual scram C. High flux IRM D. Scram discharge volume high level E. APRM 15% scram

8. Not required to be operablo when primary containment integrity io not required.

9. ?tot required if all main stoamlineo are J

isolated.

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! ~'

PROPOSED UNIT 3 TECHNICAL SPECIFICATION REVISIONS

. LIHITINC CONDITIONS POR OPERATION SURVEILLANCE REQUIREMENTS 3 1 REACTOR'PROTECTION SYSTEM 4a 1 REACTOR PROTECTION SYSTEM A licabilit A licabilit Applies to the surveillance of Applies to the instrumentation the instrumentation and 4nd associated devices which associated devices which ini ~~ate a reactor scram. ini tia te reactor scram.

Q+b a: Giye To specify the type and

~Ob 6LtiV6 frequency of surveillance to be applied to the protection To assure the operability of instrumentation.

the reactor protection system.

NL S ecificetion A- Instrumentation systems shall befunctionally tested and calibrated as ti'hen there is fuel in the vessel, indicated in Tables 4. 1.A The 'setpoints, minimum number and 4. 1. B respectively.

of trip systems, and minimum number of instrument channels that must be operable for each position of the reactor mode switch shall be as given in Table 3.1.A.

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0 NOTFS FOR TABI.E 3. l.h

1. 'fhero . hall be two operab]o or tri))p(d trip svst(ms fol each function. If the minimum number of operable instrument channels per trip system cannot be met for one trip system trip the inoperable channels or entire trip system within one hour, or, alternatively, take the below listed action for that trip function.

If the minimum number of operable instrument channels cannot be met by eitj>er trip system, the appropriate action listed below (refer to right-hand column of Table) shall be taken. An inoperable channel need not be placed in the tripped condition where this would"cause the trip function to occur. In these cases, the inoperable channel shall be restored to operable status within 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />, or take the action listed below for that trip function.

Initiate insertion of operable rode and complete insertion of all operable rode vithin four hours.

In zefuclinB cade, suspend sll operations Involving core Llterscions and fully Insert all operable control rods vier) In one hoot'.

B. Reduce pover level to ZRM range and placo mode evitch in the Startup/Hot Standby position vithin B hours.

C. Reduce turbine load and close main atoam line iaolat5.on valves vithin 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

D. Reduce pover to leaa than 30% of rated.

Scram discharqe volume high bypass may be used in ehutdovn or refuel to; bypass scram discharge volume scram vith control rod block for reactor protection system reset.

3 Deleted.

Bypassed vhen turbine first etage preaaurc ia less than 154

, pslge

5. IRM's are bypaaaed vhcn APRM'a are onacale and tho reactor mode ovitch ia in the run position The design permits closure of any tvo linea without a scram being initiated.

when the reactor is subcritical and the rea8tor voter tent)erature ia less than 212oF, only tho folloving trip functions need to be operable!

A. Mode avitch in shutdovn B. Manual scram C. High flux ZRM D. Scram discharge volume high level.

E. APRM 15% scram

8. Hot required to be operabla vhen primary containment integrity ia not required.

9. Hot requi'red if all main atoamlinea are isolated.

10. Hat required to be operabl'o vhen the reactor proaeuro veeaol head is not bolted to thc veaael ~

11. The ApRM dovnscale trip'unction ia only active vhcn tho reactor mode avitch ia in run.

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ENCLOSURE 2 DESCRIPTION AND JUSTIFICATION (TVA BFNP TS 200 SUPPLEMENT l)

Description of Change Technical Specification section 4.1.C contains a requirement that upon the failure of a reactor protection system (RPS) channel in the unsafe condition all RPS channels monitoring the, same variable must be functionally tested.

This testing must be performed immediately before the trip system containing the failure is tripped. The trip system may be in the untripped position for up to eight hours to perform the functional test.

The RPS is made up of two independent trip systems. There are usually four channels provided to monitor each critical parameter, with two channels in each trip system. The outputs of the channels in a trip system are combined in logic such that ei,ther channel trip will trip that trip system. The simultaneous tripping of both trip systems will produce a reactor scram.

An unsafe failure means that the failure did not result in tripping the channel and thus the trip system. Testing the other channels ensures that there are no other unsafe failures. However, in order to do this testing, the trip system containing the failure can be left as is for up to eight hours in order to test the other. trip system.

The proposed revision is to delete the functional test requirement and change note 1 forTable 3.1.A to provide an alternative of tripping the inoperable channels within one hour or taking the action listed for that trip function.

The note would also allow two hours to restore operable status to one channel, if placing that channel in the tripped condition would cause the trip function to occu'r. The proposed amendment is consistent with the Standard Technical Specifications.

Justification The FSAR section 7 .2.2.7 .b states: "Any one intentional bypass, maintenance operation, calibration operation, or test to verify operational availability shall not impair the ability of the reactor protection system to respond correctly." The current technical specifications allow leaving the trip system containing the unsafe failure in the untripped condition for up to eight hours in order to functionally test the other trip systems. This could possibly lead to a situation which could impair the ability of the RPS to respond correctly. By tripping the channel within one hour, the probability of

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impairing the response of the RPS is decreased, and thus, the margin of safety is increased. The proposed revision also makes this section like that in the Standard Technical Specific'ations.