ML052850349

Request to Supercede a License Amendment Request Associated with Steam Generator Replacement and Power Uprate

ML052850349
Person / Time
Site:	Palo Verde
Issue date:	09/29/2005
From:	Mauldin D Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
102-05351-CDM/TNW/RAB
Download: ML052850349 (49)

Text

L A4 S 10 CFR 50.90 David Mauldin Vice President Mail Station 7605 Palo Verde Nuclear Nuclear Engineering Tel: 623-393-5553 PO Box 52034 Generating Station and Support Fax: 623-393-6077 Phoenix, Arizona 85072-2034 102-05351 -CDM/TNW/RAB ATTN: Document Control Desk September 29, 2005 U. S. Nuclear Regulatory Commission Washington, DC 20555-0001

Reference:

1. Letter 102-05306-CDM/TNW/RAB, dated July 9, 2005, from C. D.

Mauldin, APS to U. S. Nuclear Regulatory Commission, 'Request for a License Amendment to Modify Reactor Protective and Engineered Safety Features Actuation Systems Instrumentation Technical Specification Tables"

2. Letter 102-05116-CDMITNW/RAB, Dated July 9, 2004, from C. D.

Mauldin, APS, to U. S. Nuclear Regulatory Commission, 'Request for a License Amendment to Support Replacement of Steam Generators and Uprated Power Operations in Units 1 and 3, and Associated Administrative Changes for Unit 2"

3. Letter 102-05315-CDM/TNW/RAB, dated August 3, 2005, from C. D.

Mauldin, APS to U.S. Nuclear Regulatory Commission, "Supplement to Amendment Requests Associated with Power Uprate - New Retyped Technical Specification Page"

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

Units 1, 2 and 3, Docket Nos. STN 50-52815291530 Request to Supercede a License Amendment Request Associated With Steam Generator Replacement and Power Uprate Arizona Public Service Company (APS) is requesting to supercede the amendment requested in Reference 1 with the request being made in this letter. The previous request was made using the guidance that existed at the time of the request. The Nuclear Regulatory Commission (NRC) has subsequently revised its guidance and has requested that APS upgrade its previous request.

The amendment request would ensure that if the as-found setpoint was outside of its predetermined as-found acceptance criteria band, the channel would be evaluated to verify that it is functioning as required before it is returned to service. Additionally, if the as-found setpoint is not conservative with respect to the Allowable Value, the channel will be declared inoperable. The proposed amendment would apply to the safety-related instrument setpoint changes requested in Reference 2.

A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway

• Comanche Peak

• Diablo Canyon

• Palo Verde

• South Texas Project

• Wolf Creek

ATTN: Document Control Desk U. S. Nuclear Regulatory Commission Request to Supercede a License Amendment Request Associated With Steam Generator Replacement and Power Uprate Page 2 One of the changes requested in Reference I would have also added a footnote to Table 3.7.1-1, on Page 3.7.1-4. This change was requested based on APS' understanding of the guidance provided at that time. Since there is no specific surveillance requirement associated with the setpoints being changed in Table 3.7.1-1, APS is not requesting that any footnotes be added to TS 3.7.1. In Reference 3, APS provided a revision of Table 3.7.1-1, based on Amendment 155, to replace the version in Reference 1. A revised, retyped page 3.7.1-4, based on Amendment 155, is included in Attachment 2.

Based on the responses to the three criteria provided for determining whether a significant hazard consideration exists as stated in 10 CFR 50.92, APS has concluded that the proposed amendment involves no significant hazard considerations.

APS requests approval of this amendment concurrent with the approval of the amendment requested in Reference 2. Once approved, the amendment will be implemented within 120 days.

As a result of continuing discussions with the NRC staff concerning the implementation of the proposed PUR amendment and an implementation schedule for changes to the station blackout coping time, APS has agreed to a delay to the NRC review of the proposed PUR amendment. APS requests approval of the proposed PUR amendment by November 18, 2005, instead of September 30, 2005 as requested in APS letter no.

102-05283, dated June 2, 2005.

In accordance with the PVNGS Quality Assurance Program, the Plant Review Board and the Offsite Safety Review Committee have reviewed and concurred with this proposed amendment. By copy of this letter, this submittal is being forwarded to the Arizona Radiation Regulatory Agency (ARRA) pursuant to 10 CFR 50.91(b) (1).

No commitments are being made to the NRC in this letter:

Should you have any questions, please call Mr. Thomas N. Weber at (623) 393-5764.

Sincerely, CDMITNW/RAB

ATTN: Document Control Desk U. S. Nuclear Regulatory Commission Request to Supercede a License Amendment Request Associated With Steam Generator Replacement and Power Uprate Page 3

Enclosures:

1. Notarized Affidavit

2. Arizona Public Service Company's Evaluation of the Proposed Change Attachments:

1. Proposed Technical Specification Changes (marked-up)

2. Proposed Technical Specification Changes (re-typed)

3. Changes to TS Bases (for information only) cc: B. S. Mallett NRC Region IV Regional Administrator M. B. Fields NRC NRR Project Manager G. G. Wamick NRC Senior Resident Inspector A. V. Godwin Arizona Radiation Regulatory Agency (ARRA)

ENCLOSURE I NOTARIZED AFFIDAVIT STATE OF ARIZONA

) ss.

COUNTY OF MARICOPA )

1, David Mauldin, represent that I am Vice President Nuclear Engineering and Support, Arizona Public Service Company (APS), that the foregoing document has been signed by me on behalf of APS with full authority to do so, and that to the best of my knowledge and belief, the statements made therein are true and correct.

Davi vi Sworn To Before Me This DYq'Day Of SI r t 7 , 2005.

ii OSUSIE LYNN ERGISH Notary Publc Aazona M actoMpCounty Notary-74-b4 (l Li MCOMM. ExpkwUs 14, 2007 Notary Commission Stamp

ENCLOSURE 2 ARIZONA PUBLIC SERVICE COMPANYS EVALUATION OF THE PROPOSED CHANGE Proposed Change to Technical Specifications 3.3.1, 3.3.2, and 3.3.5 1.0 Description 2.0 Proposed Change

3.0 Background

4.0 Technical Analysis 5.0 Regulatory Safety Analysis 5.1 No Significant Hazards Consideration 5.2 Applicable Regulatory Requirements 6.0 Environmental Consideration 7.0 Precedent

1.0 DESCRIPTION

This letter is a request to amend Operating Licenses NPF-41, NPF-51, and NPF-74 for the Palo Verde Nuclear Generating Station Units 1, 2 and 3.

The proposed changes supplement the changes requested in the letter from APS to USNRC dated July 9, 2004. The changes requested in this letter would add a footnote in Tables 3.3.1-1 (Before CPC Upgrade), 3.3.1-1 (After CPC Upgrade), 3.3.2-1, and 3.3.5-1 specifying action to ensure operability of the channel. These supplemental changes are requested in accordance with a request from the NRC staff.

2.0 PROPOSED CHANGE

The proposed amendment would make the following changes.

A. Revise Table 3.3.1-1 (Before CPC Upgrade) to add a footnote to function 6, Steam generator #1 Pressure - Low and function 7, Steam Generator #2 Pressure - Low.

B. Revise Table 3.3.1-1 (After CPC Upgrade) to add a footnote to function 6, Steam generator #1 Pressure - Low and function 7, Steam Generator #2 Pressure -

Low.

C. Revise Table 3.3.2-1 to add a footnote to function 2, Steam Generator #1 Pressure - Low and function 3, Steam Generator #2 Pressure - low.

D. Revise Table 3.3.5-1 to add a footnote to function 4a, Steam Generator #1 Pressure - Low and function 4b, Steam Generator #2 Pressure - Low.

The same two-part footnote would be added to the four Tables:

1. If the as-found channel setpoint is conservative with respect to the Allowable Value but outside its predetermined as-found acceptance criteria band, then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service. If the as-found instrument channel setpoint is not conservative with respect to the Allowable Value, the channel shall be declared inoperable.

2. The instrument channel setpoint shall be reset to a value that is within the as-left tolerance of the UFSAR Trip Setpoint, or within the as left tolerance of a setpoint that is more conservative than the UFSAR Trip Set Point; otherwise the channel shall be declared inoperable. The UFSAR Trip Setpoint and the methodology used to determine 1) the UFSAR Trip Setpoint, 2) the predetermined as found acceptance criteria band, and 3) the as-left setpoint tolerance band are specified in the UFSAR.

1

3.0 BACKGROUND

On July 9, 2004, Arizona Public Service Company (APS) submitted an amendment request to support replacement of steam generators and uprated power operation in Units 1 and 3. During the review of the requested amendment, the NRC staff requested additional information concerning calculation of uncertainties for the reactor protection and engineered safety features actuation system setpoints that would change as a result of the requested amendment. On March 31, 2005 the NRC staff, in a letter to Mr.

Alex Marion, NEI, established a process that utilities could use to respond to RAls that have been issued for similar licensing action requests (LARs). In a letter dated July 9, 2005, APS requested a license amendment request to comply with guidance of the letter to NEI. In a letter to NEI, dated September 7, 2005, the Nuclear Regulatory Commission has subsequently revised its guidance and has requested that APS upgrade its previous request.

This amendment is requested to add the footnote described above to ensure that if the as-found setpoint was outside of its predetermined as-found acceptance criteria band, the channel would be evaluated to verify that it is functioning as required before it is returned to service. Additionally, if the as-found setpoint is not conservative with respect to the Allowable Value, the channel will be declared inoperable. The footnote would apply to the technical specifications for the Limiting Safety System Settings (LSSS) to be changed by the request made on July 9, 2004.

3.1 System Description LCO 3.3.1, Reactor Protective System Instrumentation - Operating and Table 3.3.1-1, which it references, specify the required number of channels operable for each reactor trip function, the applicable modes for each function, the surveillance requirements, and the allowable value for the setpoint to ensure that the purpose of the function is satisfied. The Steam Generator Pressure - Low trip function (items 6 and 7 in Table 3.3.1-1) provides protection against an excessive rate of heat extraction from the steam generators and the resulting rapid, uncontrolled cooldown of the Reactor Coolant System (RCS). This trip is needed to shut down the reactor and assist the Engineered Safety Features (ESF) system in the event of a Main Steam Line Break (MSLB) or Main Feedwater Line Break (MFWLB) accident. A Main Steam Isolation Signal (MSIS) is initiated simultaneously.'

LCO 3.3.2, Reactor Protective System Instrumentation - Shutdown and Table 3.3.2-1, which it references, specify the required number of channels operable for each reactor trip function, the applicable modes for each function, the surveillance requirements, and the allowable value for the setpoint to ensure that the purpose of the function is satisfied. The Steam Generator Pressure - Low trip function (items 2 and 3 in Table 3.3.2-1) provides shutdown margin to prevent or minimize the return to power following a large MSLB in Mode 3.2 1 TS Bases B.3.3.1, Applicable Safety Analysis 2

TS Bases B3.3.2, Applicable Safety Analysis 2

LCO 3.3.5, Engineered Safety Features Actuation System Instrumentation and Table 3.3.5-1, which it references specify the required number of channels operable for each reactor trip function, the applicable modes for each function, and the allowable value for the setpoint to ensure that the purpose of the function is satisfied. The Steam Generator Pressure - Low signal actuates a MSIS to prevent an excessive rate of heat extraction and subsequent cooldown of the RCS in the event of a MSLB or MFWLB. 3 3.2 Need for the Proposed Change The amendment request would ensure that if the as-found setpoint was outside of its predetermined as-found acceptance criteria band, the channel would be evaluated to verify that it is functioning as required before it is returned to service. Additionally, if the as-found setpoint is not conservative with respect to the Allowable Value, the channel will be declared inoperable.

4.0 TECHNICAL ANALYSIS

Ensuring that the as-left instrument setting is within the as-left tolerance band of the field installed trip setpoint is a technical requirement established in the associated Design Instrumentation & Controls Uncertainty and Setpoint Calculation. In order to keep the results of these calculations associated with establishing trip setpoints valid, as-found and as-left instrument setting tolerances have been developed in the calculations. The as-found and as-left instrument setting tolerances are currently documented in the Plant Protective System (PPS) Bistable Trip Units Functional Test used to fulfill the surveillance requirements associated with the Steam Generator Low Pressure trip setpoint and others listed in Technical Specification Tables 3.3.1-1, 3.3.2-1 and 3.3.5-1.

The requirement to ensure the as-left instrument setting is within the as-left tolerance band of the trip setpoint already exists at Palo Verde and is procedurally controlled.

6.0 REGULATORY ANALYSIS

5.1 No Significant Hazards Consideration APS has evaluated whether or not a significant hazards consideration is involved with the proposed amendment by focusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," as discussed below:

1. Do the proposed changes involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No.

3 TS Bases B3.3.5, Applicable Safety Analysis 3

The proposed change does not result in any change to safety analysis methods or results, and the proposed change is not the result of a new or changed analysis. The changes to add footnotes in Technical Specification (TS) Tables 3.3.1-1, 3.3.2-1, and 3.3.5-1 ensure that the low steam generator pressure setpoints and the variable overpower trip setpoints, under specified conditions, associated with the Plant Protective System (PPS) are set to protect the safety limit.

The proposed change only ensures that if the as-found setpoint was outside of its predetermined as-found acceptance criteria band, the channel would be evaluated to verify that i is functioning as required before it is returned to service.

Additionally, if the as-found setpoint is not conservative with respect to the Allowable Value, the channel will be declared inoperable. Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Do the proposed changes create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No.

Adding footnotes to TS Tables 3.3.1-1, 3.3.2-1, and 3.3.5-1 is not a change to the setpoints, operation or accident response of the Palo Verde Nuclear Generating Station (PVNGS) Units 1, 2 and 3 structures, systems, and components. The changes ensure that certain setpoints associated with the PPS are set to protect the safety limit.

The only changes being proposed will ensure that PPS as left set points for low steam generator pressure, under specified conditions, are set to protect safety limits. Therefore, the proposed change does not create the possibility of a new or different kind of accident from any previously evaluated.

3. Does the proposed change involve a significant reduction in a margin of safety?

Response: No.

The proposed change does not result in any change to safety analysis methods or results. Therefore, by adding the footnotes to TS Tables 3.3.1-1, 3.3.2-1, and 3.3.5-1, the margins as established in the PVNGS Units 1, 2 and 3 Technical Specifications and Updated Final Safety Analysis Report (UFSAR) are unchanged.

The proposed change only involves the addition of footnotes to ensure that as left setpoints for low steam generator pressure, under specified conditions, are 4

set to protect safety limits. Margin of safety is associated with confidence in the ability of the fission product barriers (i.e., fuel and fuel cladding, reactor coolant system pressure boundary, and containment structure) to limit the level of radiation dose to the public. No actual plant equipment or accident analysis will be affected by the proposed changes. Additionally, the proposed changes will not relax any criteria used to establish safety limits, will not relax any safety system settings, or will not relax the bases for any limiting conditions for operation.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based upon the above, APS concludes that the proposed amendments present no significant hazards consideration under the standards set forth in 10 CFR 50.92 (c), and, accordingly, a finding of "no significant hazards consideration" is justified.

5.2 Applicable Regulatory RequirementslCritena The footnote ensures compliance with 10 CFR 50.36, Technical Specifications, by requiring that as-left instrument settings would be returned to a conservative value, or to declare the instrument channel inoperable.

6.0 ENVIRONMENTAL CONSIDERATION

Arizona Public Service Company has evaluated the proposed changes and has determined that the changes do not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amount of effluent that may be released offsite, or (iii) a significant increase in the individual or cumulative occupational radiation exposure. Accordingly, the proposed change meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), an environmental assessment of the proposed change is not required.

7.0 PRECEDENT This licensing action request is being submitted in accordance with guidance provided by the NRC.

5

ATTACHMENT I PROPOSED TECHNICAL SPECIFICATION CHANGES (marked-up)

RPS Instrumentation - Operating (Before CPC Upgrade) I 3.3.1 Table 3.3.1-1 (page 1 of 3)

Reactor Protective System Instrumentation APPLICABLE MODES OR OTHER SPECIFIED SURVEILLANCE FUNCTION CONDITIONS REQUIREMENTS ALLOWBLE VALUE

1. Variable Over Power 1.2 SR 3.3.1.1 Ceiling s 111.OS RTP SR 3.3.1.4 Band s 9.9S RTP SR 3.3.1.6 Incr. Rate s 11.0S/min RTP SR 3.3.1.7 Decr. Rate > 5SIsec RTP SR 3.3.1.8 SR 3.3.1.9 SR 3.3.1.13

2. Logarithmic Power Level - Hlgh(8) 2 SR 3.3.1.1 s O.011% NRTP SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.12 SR 3.3.1.13

3. Pressurizer Pressure - High 1,2 SR 3.3.1.1 s 2388 psia SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.13

4. Pressurizer Pressure - Low 1.2 SR 3.3.1.1 a 1821 psla SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.12 SR 3.3.1.13

5. Conta1rwnent Pressure - High 1,2 SR 3.3.1.1 s 3.2 psig SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.13

6. Steam Generator t1 Pressure - Low 1.2 SR 3.3.1.1 U Wt4-em44 3876 lWt RTP:

SR 3.3.1.7 2 890 psi SR 3.3.1.9 UmU2 3990 f T: 2 95 j)

SR 3.3.1.13 psi a_-_

7. Steam Generator #2 Pressure - Low 1.2 SR 3.3.1.1 Un4.t.4-W 3 3876 WIRP: 1.

SR 3.3.1.7 9 890 ps.a, SR 3.3.1.9 t 3 'OkWt:gP 2995ps SR 3.3.1.13 psia (continued)

(a) Trip may be bypassed when logarithmic power is > 1E-4t NRTP. Bypass shall be automatically removed r Is !c 1E-4% NRTP.

v l igseotr )

PALO VERDE UNITS 1 AND 3 AMENDMENT NO. 49, 440 PALO VERDE UNIT 2 3.3.1-8 AMENDMENT NO. 449. 460

INSERT A

1. If the as-found channel setpoint is conservative with respect to the Allowable Value but outside its predetermined as-found acceptance criteria band, then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service. If the as-found instrument channel setpoint is not conservative with respect to the Allowable Value, the channel shall be declared inoperable.

2. The instrument channel setpoint shall be reset to a value that is within the as-left tolerance of the UFSAR Trip Setpoint, or within the as left tolerance of a setpoint that is more conservative than the UFSAR Trip Set Point; otherwise the channel shall be declared inoperable. The UFSAR Trip Setpoint and the methodology used to determine

1) the UFSAR Trip Setpoint, 2) the predetermined as found acceptance criteria band, and 3) the as-left setpoint tolerance band are specified in the UFSAR.

RPS Instrumentation - Operating (After CPC Upgrade) 3.3.1 Table 3.3.1-1 (page 1 of 3)

Reactor Protective System Instrumentat0on APPLICABLE MODES OR OTHER SPECIFIED SURVEILLANCE FUNCTION CONDITIONS REQUIREMENTS ALLOWABLE VALUE

1. Variable Over Power 1,2 SR 3.3.1.1 Ceiling s 111.0 RTP SR 3.3.1.4 Band s 9.9S RTP SR 3.3.1.6 Incr. Rate s 11.0S/min RTP SR 3.3.1.7 Decr. Rate > 5S/sec RTP SR 3.3.1.8 SR 3.3.1.9 SR 3.3.1.13

2. Logarithmic Power Level - High(a) 2 SR 3.3.1.1 s 0.011O NRTP SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.12 SR 3.3.1.13

3. Pressurizer Pressure - High 1.2 SR 3.3.1.1 s 2388 psia SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.13

4. Pressurizer Pressure - Low 1.2 SR 3.3.1.1 2 1821 psla SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.12 SR 3.3.1.13

5. ContaIrnent Pressure - High 1.2 SR 3.3.1.1 s 3.2 psig SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.13

6. Steam Generator #1 Pressure - Low 1.2 SR 3.3.1.1 Un4t 1 and - 3876 Wt RTP:

SR 3.3.1.7 k 890 psil7 SR 3.3.1.9 SR 3.3.1.13 n# 3990 W~t RTP: z: 95t psia

7. Steam Generator #2 Pressure - Low 1.2 SR 3.3.1.1 Ui

+a-4J4 3876 WIt RTP:

SR 3.3.1.7 2 890 psi SR 3.3.1.9 SR 3.3.1.13 Unit 3990 Oft RiP: 2 ps1b (continued)

(a) Trip may be bypassed when logarithnic power is > 1E-4S NRTP. Bypass shall be automatically removed when logarithmic power is s 1E-4S NRTP.

(* V/A U23)

,ZNTSAA \

PALO VERDE UNITS 1.2.3 3.3.1-17 AMENDMENT NO. 4bQ

INSERT A

1. If the as-found channel setpoint is conservative with respect to the Allowable Value but outside its predetermined as-found acceptance criteria band, then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service. If the as-found instrument channel setpoint is not conservative with respect to the Allowable Value, the channel shall be declared inoperable.

2. The instrument channel setpoint shall be reset to a value that is within the as-left tolerance of the UFSAR Trip Setpoint, or within the as left tolerance of a setpoint that is more conservative than the UFSAR Trip Set Point; otherwise the channel shall be declared inoperable. The UFSAR Trip Setpoint and the methodology used to determine

1) the UFSAR Trip Setpoint, 2) the predetermined as found acceptance criteria band, and 3) the as-left setpoint tolerance band are specified in the UFSAR.

RPS Instrumentation - Shutdown 3.3.2 Table 3.3.2-1 Reactor Protective System Instrumentation - Shutdown APPLICABLE MODES OR OTHER SPECIFIED SURVEILLANCE FUNCTION CONDITIONS REOUIREMENTS ALLOWABLE VALVE

1. Logarithmic Power Level-H1ghtd) 3(a) 4(a) 5(a) SR 3.3.2.12 o.oiit NRTP(C)

SR 3.3.2.2 SR 3.3.2.3 SR 3.3.2.4 SR 3.3.2.5 3(a)

2. Steam Generator 11 Pressure-Low(b) SR 3.3.2.1 UVn#41 and 3876 -Wt SR SR 3.3.2.2 3.3.2.4 RIP: 2 e90 psia W 4 3990-PlL ftW$m I

SR 3.3.2.5 2 955 si V

3. Steam Generator R2 Pressure-Low(b) 3(a) SR 3.3.2.1 UM.pc4 d 3 3876 W

-aI SR 3.3.2.2 KIP: 2 890 psla SR 3.3.2.4 UnA4- 399 PutRP SR 3.3.2.5 2 955 ps (a) With any Reactor Trip Circuit Breakers (RTCBs) closed and any control element assembly capable of being withdrawn.

(b) The setpoint may be decreased as steam pressure is reduced, provided the margin between steam pressure and the setpolnt is maintained s 200 psig. The setpoint shall be autanatically Increased to the normal setpoint as steam pressure is increased.

(c) The setpolnt must be reduced to s IE-4S NRTP when less than 4 RCPs are running.

(d) Trip may be bypassed when logarithmic power is > 1E-4S NRTP. Bypass shall be automatically removed when logarithmic power is s 1E-4$ NRTP.

(& /)'J5LXT A PALO VERDE UNITS 1 AND 3 AMENDMENT NO. 4}4. 449 PALO VERDE UNIT 2 3.3.2-5 AMENDMENT NO. 49 49

INSERT A

1. If the as-found channel setpoint is conservative with respect to the Allowable Value but outside its predetermined as-found acceptance criteria band, then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service. If the as-found instrument channel setpoint is not conservative with respect to the Allowable Value, the channel shall be declared inoperable.

2. The instrument channel setpoint shall be reset to a value that is within the as-left tolerance of the UFSAR Trip Setpoint, or within the as left tolerance of a setpoint that is more conservative than the UFSAR Trip Set Point; otherwise the channel shall be declared inoperable. The UFSAR Trip Setpoint and the methodology used to determine

1) the UFSAR Trip Setpoint, 2) the predetermined as found acceptance criteria band, and 3) the as-left setpoint tolerance band are specified in the UFSAR.

ESFAS Instrumentation 3.3.5 Table 3.3.5-1 (page 1 of 1)

Engineered Safety Features Actuation System Instrumentatlon APPLICABLE MOES OR OTHER SPECIFIED FUNCTION CONDITIONS ALLOWABLE VALUE

1. Safety InJection Actuation Signal

a. Contarinent Pressure - Hiwoh 1.2,3 :s3.2 psig

b. Pressurizer Pressure - Low a) z 1821 psla

2. Contaircent Spray Actuation Signal

a. Containment Pressure - High High 1.2.3 s 8.9 psig

3. Containment Isolation Actuation Signal

a. Containment Pressure - High 1.2.3 s 3.2 psig

b. Pressurizer Pressure - Lowa) 2 1821 psia

4. Main Steam Isolation Slgnal(c)

a. Steam Generator #1 Pressure-Low(b) 1.2.3 Un4t--Ind4-3 3876 Wt RTP7tN 4

k 890 PSI

b. Steam Generator #2 Pressure-Low(b) U 23990Mt RTP: P

c. Steam Generator f1 Level-High Un#i4.4 and3 3876 t RTP " S

d. Steam Generator 12 Level-High E90 sz;i B

e. Containment Pressure-High kUni>t4 3990 lWt RTP: . 9$ Z9 s 91.5S s 91.5S s 3.2 psig

5. Recirculation Actuation Signal

a. Refueling Water Storage Tank Level-Low 1.2.3 2 6.9 and s 7.9S

6. Auxiliary Feedwater Actuation Signal SG J1 (AFAS-1)

a. Steam Generator 11 Level-Low 1.2.3 k 25.3%

b. SG Pressure Difference-High s 192 psid

7. Auxiliary Feedwater Actuation Signal SG #2 (AFAS-2)

a. Steam Generator #2 Level-Low 1,2.3 2 25.3S

b. SG Pressure 0ifference-HIgh s 192 psid (a) The setpoint may be decreased to a mininum value of 100 psia. as pressurizer pressure is reduced.

provided the margin between pressurizer pressure and the setpoint is maintained s 400 psia or k 140 psia greater than the saturation pressure of the RCS cold leg when the RCS cold le tenperature is 2 485'F. Trips may be bypassed when pressurizer pressure Is < 400 psia. Bypass snall De automatically removed when pressurizer pressure is 2 500 psia. The setpoint shall be automatically increased to the normal setpoint as pressurizer pressure is increased.

(b) The setpolnt may be decreased as steam pressure Is reduced. provided the margin between steam pressure and the setpoint is maintained s 200 psig. The setpoint shall be automatically increased to the normal setpoint as steam pressure is increased.

PALO VERDE UNITS 1 AND 3 AMENDMENT NO. 4 PALO VERDE UNIT 2 3.3.5-4 AMENDMENT NO. 1 449

ESFAS Instrumentation 3.3.5 (c) The Main Steam Isolation Signal (MSIS) Function (Steam Generator Pressure - Low. Steam Generator Level-High and Contalnment Pressure - High signals) is not required to be OPERABLE when all associated valves lated by the MSIS Function are closed.

(,M) /AS) /

PALO VERDE UNITS 1 AND 3 AMENDMENT NO. 44-PALO VERDE UNIT 2 3.3.5-4 AMENDMENT NO. 44w 449

INSERT A

1. If the as-found channel setpoint is conservative with respect to the Allowable Value but outside its predetermined as-found acceptance criteria band, then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service. If the as-found instrument channel setpoint is not conservative with respect to the Allowable Value, the channel shall be declared inoperable.

2. The instrument channel setpoint shall be reset to a value that is within the as-left tolerance of the UFSAR Trip Setpoint, or within the as left tolerance of a setpoint that is more conservative than the UFSAR Trip Set Point; otherwise the channel shall be declared inoperable. The UFSAR Trip Setpoint and the methodology used to determine

1) the UFSAR Trip Setpoint, 2) the predetermined as found acceptance criteria band, and 3) the as-left setpoint tolerance band are specified in the UFSAR.

ATTACHMENT 2 PROPOSED TECHNICAL SPECIFICATION CHANGES (retyped)

RPS Instrumentation - Operating (Before CPC Upgrade) 3.3.1 Table 3.3.1-1 (page 1 of 3)

Reactor Protective System Instrumentation APPLICABLE MODES OR OTHER SPECIFIED SURVEILLANCE FUNCTION CONDITIONS REQUIREMENTS ALLOWABLE VALUE

1. Variable Over Power 1.2 SR 3.3.1.1 Ceiling s 111.0 RTP SR 3.3.1.4 Band s 9.92 RTP SR 3.3.1.6 Incr. Rate s 11.0O/min RTP SR 3.3.1.7 Decr. Rate > 52/sec RTP SR 3.3.1.8 SR 3.3.1.9 SR 3.3.1.13

2. Logarithmic Power Level - High(a) 2 SR 3.3.1.1  ! O.O11 NRTP SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.12 SR 3.3.1.13

3. Pressurizer Pressure - High 1.2 SR 3.3.1.1 s 2388 psia SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.13

4. Pressurizer Pressure - Low 1.2 SR 3.3.1.1 a 1821 psia SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.12 SR 3.3.1.13

5. Containment Pressure - High 1.2 SR 3.3.1.1 s 3.2 psig SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.13

6. Steam Generator #1 Pressure - Low 1.2 SR 3.3.1.1 3876 MWtt RTP: a 890 psla SR 3.3.1.7 SR 3.3.1.9 3990 MWt RTP: 2 955 psia( I SR 3.3.1.13

7. Steam Generator #2 Pressure - Low 1.2 SR 3.3.1.1 3876 MWt RTP: 2 890 psia SR 3.3.1.7 3990 MWt RTP: 2 955 psia("M I SR 3.3.1.9 SR 3.3.1.13 (continued)

(a) Trip may be bypassed when logarithmic power Is > 1E-41 NRTP. Bypass shall be automatically removed when logarithmic power is s 1E-4% NRTP.

(aa) 1. If the as-found channel setpoint isconservative with respect to the Allowable Value but outside its predetermined as-found acceptance criteria band. then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service. If the as-found instrument channel setpoint is not conservative with respect to the Allowable Value, the channel shall be declared Inoperable.

2. The instrument channel setpoint shall be reset to a value that is within the as-left tolerance of the UFSAR Trip Setpoint. or within the as left tolerance of a setpoint that Ismore conservative than the UFSAR Trip Set Point: otherwise the channel shall be declared Inoperable. The UFSAR Trip Setpoint and the methodology used to determine 1) the UFSAR Trip Setpoint. 2) the predetermined as found acceptance criteria band, and 3) the as-left setpoint tolerance band are specified in the UFSAR.

PALO VERDE UNITS 1, 2.3 3.3.1-8 AMENDMENT NO. X.64

RPS Instrumentation - Operating (After CPC Upgrade) 3.3.1 Table 3.3.1-1 (page 1 of 3)

Reactor Protective System Instrumentation APPLICABLE MODES OR OTHER SPECIFIED SURVEILLANCE FUNCTION CONDITIONS REQUIREMENTS ALLOWABLE VALUE

1. Variable Over Power 1.2 SR 3.3.1.1 Ceiling S 111.0Z RTP SR 3.3.1.4 Band s 9.9: RTP SR 3.3.1.6 Incr. Rate s 11.0%/min RTP SR 3.3.1.7 Decr. Rate > 5%/sec RTP SR 3.3.1.8 SR 3.3.1.9 SR 3.3.1.13

2. Logarithmic Power Level - High(a) 2 SR 3.3.1.1 S 0.011% NRTP SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.12 SR 3.3.1.13

3. Pressurizer Pressure - High 1.2 SR 3.3.1.1 s 2388 psla SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.13

4. Pressurizer Pressure - Low 1.2 SR 3.3.1.1 2 1821 psia SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.12 SR 3.3.1.13

5. Containment Pressure - High 1.2 SR 3.3.1.1 s 3.2 psig SR 3.3.1.7 SR 3.3.1.9 SR 3.3.1.13

6. Steam Generator #1 Pressure - Low 1,2 SR 3.3.1.1 3876 MWt RTP: 2 890 psia SR 3.3.1.7 3990 MWt RTP: 2 955 psia)'

SR 3.3.1.9 SR 3.3.1.13

7. Steam Generator #2 Pressure - Low 1.2 SR 3.3.1.1 3876 MWIt RTP: 2 890 psia SR 3.3.1.7 3990 MWt RTP: 2 955 psial")

SR 3.3.1.9 SR 3.3.1.13 (continued)

(a) Trip may be bypassed when logarithmic power is > 1E-42 NRTP. Bypass shall be automatically removed when logarithmic power Is s 1E-42 NRTP.

(aa) 1. If the as-found channel setpoint is conservative with respect to the Allowable Value but outside its predetermined as-found acceptance criteria band, then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service. If the as-found instrument channel setpoint is not conservative with respect to the Allowable Value, the channel shall be declared inoperable.

2. The instrument channel setpoint shall be reset to a value that is within the as-left tolerance of the UFSAR Trip Setpoint. or within the as left tolerance of a setpoint that is more conservative than the UFSAR Trip Set Point: otherwise the channel shall be declared inoperable. The UFSAR Trip Setpoint and the methodology used to determine 1) the UFSAR Trip Setpoint. 2) the predetermined as found acceptance criteria band, and 3) the as-left setpoint tolerance band are specified in the UFSAR.

PALO VERDE UNITS 1.2.3 3.3.1-17 AMENDMENT NO. Gil,

RPS Instrumentation - Shutdown 3.3.2 Table 3.3.2-1 Reactor Protective System Instrumentation - Shutdown APPLICABLE MODES OR OTHER SPECIFIED SURVEILLANCE FUNCTION CONDITIONS REQUIREMENTS ALLOWABLE VALVE 3(a). 4(a). 5(a)

1. Logarithmic Power Level-Hlgh(d SR 3.3.2.1 s 0.0112 NRTP(C)

SR 3.3.2.2 SR 3.3.2.3 SR 3.3.2.4 SR 3.3.2.5

2. Steam Generator #1 Pressure-Low(b) 3(a)

SR 3.3.2.1 3876 MWt RTP: 2 890 psia SR 3.3.2.2 3990 MWt RTP: 2 955 psiate SR 3.3.2.4 SR 3.3.2.5

3. Steam Generator #2 Pressure-Low(b) 3(a) SR 3.3.2.1 3876 MWt RTP: 2 890 psia SR 3.3.2.2 3990 MWt RTP: 2 955 psia(")

SR 3.3.2.4 SR 3.3.2.5 (a) With any Reactor Trip Circuit Breakers (RTCBs) closed and any control element assembly capable of being withdrawn.

(b) The setpoint may be decreased as steam pressure is reduced. provided the margin between steam pressure and the setpoint is maintained s 200 psig. The setpoint shall be automatically increased to the normal setpoint as steam pressure Is increased.

(c) The setpolnt must be reduced to s 1E-4Z NRTP when less than 4 RCPs are running.

(d) Trip may be bypassed when logarithmic power is > IE-4% NRTP. Bypass shall be automatically removed when logarithmic power Is s 1E-4Z NRTP.

(e) 1. If the as-found channel setpoint Is conservative with respect to the Allowable Value but outside its predetermined as-found acceptance criteria band. then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service. If the as-found instrument channel setpolnt is not conservative with respect to the Allowable Value. the channel shall be declared Inoperable.

2. The instrument channel setpoint shall be reset to a value that is within the as-left tolerance of the UFSAR Trip Setpoint. or within the as left tolerance of a setpoint that is more conservative than the UFSAR Trip Set Point: otherwise the channel shall be declared inoperable. The UFSAR Trip Setpoint and the methodology used to determine 1) the UFSAR Trip Setpoint. 2) the predetermined as found acceptance criteria band, and 3) the as-left setpolnt tolerance band are specified in the UFSAR.

PALO VERDE UNITS 1 AND 3 AMENDMENT NO. 14g, PALO VERDE UNIT 2 3.3.2-5 AMENDMENT NO. 449.

ESFAS Instrumentation 3.3.5 Table 3.3.5-1 (page 1 of 1)

Engineered Safety Features Actuation System Instrumentation APPLICABLE MODES OR OTHER SPECIFIED FUNCTION CONDITIONS ALLOWABLE VALUE

1. Safety Injection Actuation Signal

a. Contarinment Pressure - High 1.2,3 s 3.2 psig

b. Pressurizer Pressure - Low(a) 1 1821 psia

2. Containment Spray Actuation Signal

a. Containment Pressure - High High 1.2.3 s 8.9 psig

3. Containment Isolation Actuation Signal

a. Containment Pressure - High_ 1,2.3 s 3.2 psig

b. Pressurizer Pressure - Lowd a 2 1821 psia

4. Main Steam Isolation Signal(c)

a. Steam Generator #1 Pressure-Low(b) 1.2.3 3876 MWt RTP: i 890 psla 3990 MWt RTP: 2 955 psia'd

b. Steam Generator #2 Pressure-Low(b) 3876 MWt RTP: 2 890 psia 3990 HMWt RTP: 2 955 psia'l' I

c. Steam Generator #1 Level-High s 91.52

d. Steam Generator #2 Level-High s 91.52

e. Containment Pressure-High s 3.2 psig

5. Recirculation Actuation Signal

a. Refueling Water Storage Tank Level-Low 1,2.3 2 6.9 and s 7.9%

6. Auxiliary Feedwater Actuation Signal SG#1 (AFAS-1)

a. Steam Generator #1 Level-Low 1.2,3 2 25.32

b. SG Pressure Difference-High s 192 psid

7. Auxiliary Feedwater Actuation Signal SG #2 (AFAS-2)

a. Steam Generator #2 Level-Low 1.2.3 2 25.32

b. SG Pressure Difference-High 5 192 psid (a) The setpoint may be decreased to a minimum value of 100 psia, as pressurizer pressure is reduced.

provided the margin between pressurizer pressure and the setpoint is maintained s 400 psia or 2 140 psia greater than the saturation pressure of the RCS cold leg when the RCS cold leg temperature is 2 485*F. Trips may be bypassed when pressurizer pressure is < 400 psia. Bypass shall be automatically removed when pressurizer pressure is 2 500 psia. The setpoint shall be automatically increased to the normal setpoint as pressurizer pressure is increased.

(b) The setpoint may be decreased as steam pressure is reduced. provided the margin between steam ressure and the setpoint is maintained s 200 psig. The setpoint shall be automatically increased ee to normal setpoint as steam pressure is increased.

(c) The Main Steam Isolation Signal (MSIS) Function (Steam Generator Pressure - Low. Steam Generator Level-High and Containment Pressure - High signals) is not required to be OPERABLE when all associated valves isolated by the MSIS Function are closed.

(d) 1. If the as-found channel setpoint is conservative with respect to the Allowable Value but outside its predetermined as-found acceptance criteria band, then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service. If the as-found Instrument channel setpoint Is not conservative with respect to the Allowable Value, the channel shall be declared inoperable.

2. The instrument channel setpoint shall be reset to a value that is within the as-left tolerance of the UFSAR Trip Setpoint. or within the as left tolerance of a setpoint that is more conservative than the UFSAR Trip Set Point: otherwise the channel shall be declared inoperable. The UFSAR Trip Setpoint and the methodology used to determine 1) the UFSAR Trip Setpoint. 2) the predetermined as found acceptance criteria band, and 3) the as-left setpoint tolerance band are specified in the UFSAR.

PALO VERDE UNITS 1 AND 3 AMENDMENT NO. 44W.

PALO VERDE UNIT 2 3.3.5-4 AMENDMENT NO. 449,

MSSVs 3.7.1 Table 3.7.1-1 (page 1 of 1)

Variable Overpower Trip Setpoint versus OPERABLE Main Steam Safety Valves MINIMUM NUMBER NUMBER OF MAXIMUM POWER MAXIMUM ALLOWABLE OF MSSVs PER INOPERABLE (% RTP) VARIABLE OVERPOWER TRIP STEAM GENERATOR MSSVs PER or HIGHEST MODE SETPOINTla, REQUIRED STEAM (% RTP)

OPERABLE GENERATOR 3876 MWt 3990 MWt 3876 MWt 3990 MWt RTP RTP RTP RTP 10 0 100.0 100.0 111.0 111.0 9 1 98.2 90.0 108.0 99.7 8 2 87.3 80.0 97.1 89.7 7 3 76.4 68.0 86.2 77.7 6 4 65.5 56.0 75.3 65.7 5 5 MODE 3 MODE 3 NA NA 4 6 MODE 3 MODE 3 NA NA 3 7 MODE 3 MODE 3 NA NA 2 8 MODE 3 MODE 3 NA NA (a)The VOPT setpoint is not required to be reset in MODE 3.

PALO VERDE UNITS 1. 2 AND 3 3.7.1-4 AMENDMENT NO. 4455.

ATTACHMENT 3 CHANGES TO TS BASES (for information only)

RPS Instrumentation - Operating B 3.3.1 B 3.3 INSTRUMENTATION B 3.3.1 Reactor Protective System (RPS) Instrumentation - Operating BASES BACKGROUND The RPS initiates a reactor trip to protect against violating the core specified acceptable fuel design limits and breaching the reactor coolant pressure boundary (RCPB) during anticipated operational occurrences (AOOs). By tripping the reactor, the RPS also assists the Engineered Safety Features (ESF) systems in mitigating accidents.

The protection and monitoring systems have been designed to ensure safe operation of the reactor. This is achieved by specifying limiting safety system settings (LSSS) in terms of parameters directly monitored by the RPS. as well as LCOs on other reactor system parameters and equipment performance.

'Except fo 'Tr'ip Funct-i 6n's 64 an d7 Athe LSSSv-defined in this Specification as the Allowable Value, in conjunction with the LCOs. establish the threshold for protective system action to prevent exceedinq-acceDtable limits durinq Design Basis Acci~dents (DBAs)* Fotr Trip Fu'nctions-61and I7.The UFSAR JTjir Set'point' s the LSSS.

During AOOs, which are those events expected to occur one or more times during the plant life, the acceptable limits are:

• The departure from nucleate boiling ratio (DNBR) shall be maintained above the Safety Limit (SL) value to prevent departure from nucleate boiling (DNB);

• Fuel centerline melting shall not occur: and

• The Reactor Coolant System (RCS) pressure SL of 2750 psia shall not be exceeded.

Maintaining the parameters within the above values ensures that the offsite dose will be within the 10 CFR 50 (Ref. 1) and 10 CFR 100 (Ref. 2) criteria during AOOs.

Accidents are events that are analyzed even though they are not expected to occur during the plant life. The acceptable limit during accidents is that the offsite dose shall be maintained within an acceptable fraction of 10 CFR 100 (continued)

PALO VERDE UNITS 1.2.3 B 3.3.1-1 REVISION 0

RPS Instrumentation - Operating B 3.3.1 BASES BACKGROUND Bistable Trip Units (Before CPC Upgrade) (continued)

Some measurement channels provide contact outputs to the PPS. In these cases, there is no bistable card, and opening the contact input directly de-energizes the associated bistable relays. These include the CPC generated DNBR - Low and LPD - High trips. The CPC auxiliary trip functions (e.g.. CPC VOPT algorithm) do not have any direct contact outputs to the PPS. The auxiliary trip functions act through the DNBR - Low and LPD - High trip contacts to de-energize the associated CPC initiation relays that provide a channel trip signal to the PPS parameters 3 and 4 bistable relays. Other CPC trip functions may also apply a penalty factor to cause a DNBR or LPD trip.

The trip setpoints used in the bistables are based on analytical limits derived from safety analyses (Ref. 5 and 8). The selection of these trip setpoints is such that adequate protection is provided when all sensor and processing time delays are ta en into account. To allow for calibration tolerances, instrumentation uncertainties, instrument drift. and severe environment errors for those RPS channels that must function in harsh environments as defined by 10 CFR 50.49 (Ref. 6). Ex-cept 'forlT~rp FunctiorIs 5nd_7__Al lowable Values soecified in 1 , in

.. Pable3 th acomoanyi nq -C._-adth IJ4SAR TiD tb ts 'Sbecif{ed.,i n_

Table -1I.62 6fthe.'UFSAR (Ref 8) forrlp Functi-on's :6and^7 ar osrvtvl djusted With respect to the analytical limits. A detailed description of the methodology used to calculate the trip setpoints. including their explicit uncertainties. is-Drovided in "Calculation of Trip Setpoint Values" (Ref. 7).;'The UFSAR' TrioaSet oolts are'basekdon the calculated ttotal: loopD uncertaintyAconsistent with the as';documen amethodoloQvted inthe.VFSAR.(RG 1.105. Revsison I-.-NoVember'$'I097.6Y;1(Ref. 14)1.Th'qeperal YeiationshfD amIr1h thSe PVNGS~tr setoomt terms his$asollows: iThe calcul ted Lirniitt'irni Se'too'ht<. tLSD).0 is-determinedwiThi:n7he blntT.

sD'ciff csset-ointtnIasis and isfabsed .on*:Pie An.y'tjal Lihtri-t'nd the! ot-a3. Looo; Unpcer~nt~ftit Thte . lES AARTr~et

$etooi~nt i. eaual 'ttooro're -.co-nserxvative than the LSo id fis 'tsoecif-, i:n the UFSAPR. -'; W QIFSA.Trisgtpihti:s the ieQiaaT '1i mei t.i n-ysetX oi nt 'Thich.preserves thCeRim,safety and is'tberefor' theLS`SS'reduired byQ.4 C 50.36.: The Desiqn'S'o1t '(OSo)' is' 'the' field in'stalld sttiin and can be' even more conservative than the UFSAR.Tri'Seto'oIit.

This relatlorshi D'ensures that sufficierit marcin to the safety limit ismaintainedMTliznmin)jl.p sit DSp (continued)

PALO VERDE UNITS 1.2.3 B 3.3.1-11 REVISION 27

RPS Instrumentation - Operating B 3.3.1 entered into the bistable is n still more I conservative than +p elt he Allowable Value to account for changes in random measurement errors detectable by a CHANNEL FUNCTIONAL TEST. One example of such a change in measurement error is drift during the interval between surveillances. A channel is inoperable if its actual setpoint is not within its Allowable Value.

To maintain the margins of safety assumed in the safety analyses, the calculations of the trip variables for the DNBR - Low and Local Power Density - high trips include the measurement, calculational, and processor uncertainties and dynamic allowances as defined in the latest applicable revision of CEN-305-P, "Functional Design Requirements for a Core Protection Calculator" (Ref. 10) and CEN-304-P." Functional Design Requirements for a Control Element Assembly Calculator." (Ref. 11). The safety (continued)

PALO VERDE UNITS 1.2,3 B 3.3.1-12 REVISION 27

RPS Instrumentation - Operating B 3.3.1 BASES BACKGROUND Bistable Trip Units (Before CPC Upgrade) (continued) analyses also credit the CPC auxiliary trip functions (VOPT.

T-hot Saturation. ASGT, and Low RCS Pressure), which act through the DNBR - Low and LPD - High trip contacts. to provide core protection during Anticipated Operational Occurrences and Design Basis Accidents (Ref. 5 and 8).

Setpoints in accordance with the Allowable Value will ensure that SLs of Chapter 2.0. "SAFETY LIMITS (SLs)." are not violated during AOOs. and the consequences of DBAs will be acceptable. providing the plant is operated from within the LCOs at the onset of the ADO or DBA and the equipment functions as designed.

Note that in LCO 3.3.1. the AllowableValues of Table 3.3.1-1 are the LSSS-,;exceDt orTri" TFunctiops;&!and 7i. Fo'r Tri F'unctions 6;ahnd 7-.The UFSAR Trjp Setpolnt is the LSSS.

Functional testing of the entire RPS, from bistable input through the opening of individual RTCBs, can be performed either at power or shutdown and is normally performed on a quarterly basis. Nuclear instrumentation. the CPCs. and the CEACs can be similarly tested. UFSAR, Section 7.2 (Ref. 8).

provides more detail on RPS testing. Processing transmitter calibration is normally performed on a refueling basis.

Bistable Trip Units (After CPC Upgrade)

Bistable trip units. mounted in the Plant Protection System (PPS) cabinet, receive an analog input from the measurement channels. They compare the analog input to trip setpoints and provide contact output to the Matrix Logic. They also provide local trip indication and remote annunciation.

There are four channels of bistables. designated A. B. C.

and D, for each RPS parameter. one for each measurement channel. Bistables de-energize when a trip occurs. in turn de-energizing bistable relays mounted in the PPS relay card racks.

The contacts from these bistable relays are arranged into six coincidence matrices, comprising and Matrix Logic. If bistables monitoring the same parameter in at least two (continued)

PALO VERDE UNITS 1.2.3 B 3.3.1-13 REVISION 26

RPS Instrumentation - Operating B 3.3.1 BASES BACKGROUND Bistable Trip Units (After CPC Upgrade) (continued)

Some measurement channels provide contact outputs to the PPS. In these cases, there is no bistable card, and opening the contact input directly de-energizes the associated bistable relays. These include the CPC generated DNBR - Low and LPD - High trips. The CPC auxiliary trip functions (e.g., CPC VOPT algorithm) do not have any direct contact outputs to the PPS. The auxiliary trip functions act through the DNBR - Low and LPD - High trip contacts to de-energize the associated CPC initiation relays that provide a channel trip signal to the PPS parameters 3 and 4 bistable relays. Other CPC trip functions may also apply a penalty factor to cause a DNBR or LPD trip.

The trip setpoints used in the bistables are based on the analytical limits derived from the accident analysis (Ref. 5). The selection of these trip setpoints is such that adequate protection is provided when all sensor and processing time delays are taken into account. To allow for calibration tolerances, instrumentation uncertainties.

instrument drift, and severe environment errors for those RPS channels that must function in harsh environments as defined-by 10 CFR 50.49 (Ref. 6). Excepo-for Trip+Functions 6,:and7-.,4-Allowable Values soecifiediJ n Taelel3,3. -1.in the accomoi LCO., the UFSARTri D Set, id Table iLU.2_Aof the

,UFSAR ARIef>r8 61rTrip Ffntsspef 6JinseIn Jd are conservatively adjusted with respect to the analytical limits. A detailed description of the methodology used to calculate the trip setpoints. including their explicit uncertainties, is.orovided in "Calculation of TrOD SetDoint-

.Values". (Ref, 7),.e..TheUFSAkTrIoet'oo nts e&base"don'the calcul ated total oo uncertainty.consistentwith the, methodolOciYas dccmented iiithe UFSAR (RG;1.105'. Revision 1R. NoveImber'^19,763 A Ref . '.1 4L>;T~h, en~ra;,r~el~atlo,'hshtamong Othe PVJ'JQS.. -t~rle~o ,setooint.t~erms: .i s'-is .:f~o~l ovis: Tihe.$lc~,ul~ted Li.ritp~

etoin~(Lp) s~et~d;hPWedwithl '-the"blant.

Limiti4'an the:t4Mtai lo&~~t ainty.-ThThFAR h Setpoi n~t- ~ s,.eoua >o o~r moire -c.nser atVie .hdn fie ;L*h An6d is eified tinhei1JFSARP- fThe.; UfS-AR Trigb!,setos tp is the ecalh!'-i m ~tj no:,,sett obint wbich" &6kNeser~,t~s~V hi and i erefreutheL Sreouie b OCF.. Te Desian nt(S)eSetoois the field istal-1 d0 tting ind. cani be even more: conservative thanh the! UFSAR TribbSetboont..

This relationshinD ensures that sufficient maroin toathe safetylimit.ismaintained. The rrd ri4-pDSp (continued)

PALO VERDE UNITS 1,2,3 B 3.3.1-15 REVISION 27

RPS Instrumentation - Operating B 3.3.1 entered into the bistable is jom&4ystill more I conservative than t -p,-,ythe Allowable Value to account for changes in random measurement errors detectable by a CHANNEL FUNCTIONAL TEST. One example of such a change in measurement error is drift during the interval between surveillances. A channel is inoperable if its actual setpoint is not within its Allowable Value.

To maintain the margins of safety assumed in the safety analyses, the calculations of the trip variables for the DNBR - Low and Local Power Density - High trips include the measurement. calculational. and processor uncertainties and dynamic allowances as defined in the latest applicable revision of CEN-305-P, "Functional Design Requirements for a I Core Protection Calculator" (Ref. 10) and CEN-304-P, "Functional Design Requirements for a Control Element I Assembly Calculator," (Ref. 11). The safety analyses (continued)

PALO VERDE UNITS 1.2.3 B 3.3.1-16 REVISION 27

RPS Instrumentation - Operating B 3.3.1 BASES BACKGROUND Bistable Trip Units (After CPC Upgrade) (continued) also credit the CPC auxiliary trip functions (VOPT, T-hot Saturation. ASGT. and Low RCS Pressure). which act through the DNBR - Low and LPD - High trip contacts. to provide core protection during Anticipated Operational Occurrences and Design Basis Accidents (Ref. 5 and 8).

Setpoints in accordance with the Allowable Value will ensure that SLs of Chapter 2.0. "SAFETY LIMITS (SLs)." are not violated during AOOs, and the consequences of DBAs will be acceptable, providing the plant isoperated from within the LCOs at the onset of the AOO or DBA and the equipment functions as designed.

Note that inLCO 3.3J.1- the Allowable Values of Table 3.3,,.1-1 are the LSSSt--,, exceotrfori'D:.unct ions6 nd7 For Triap F nctions'~ a'd 1. tb6' UFSAR rp.,Setpoiln 'ithe LSSS.

Functional testing of the entire RPS, from bistable input through the opening of individual RTCBs. can be performed either at ower or shutdown and is normallyterformed on a quarterly basis. Nuclear instrumentation, the CPCs. and the CEACs can be similarly tested. CPC and CEAC functional testing isperformed quarterly and during refueling.

UFSAR, Section 7.2 (Ref. 8). provides more detail on RPS testing. Processing transmitter calibration isnormally performed on refueling basis.

RPS Logic The RPS Logic, addressed inLCO 3.3.4. consists of both Matrix and Initiation Logic and employs a scheme that provides a reactor trip when bistables inany two of the four channels sense the same input parameter trip. This is called a two-out-of-four trip logic.

Bistable relay contact outputs from the four channels are configured into six logic matrices. Each logic matrix checks for a coincident trip inthe same parameter intwo bistable channels. The matrices are designated the AB. AC, AD. BC, BD. and CD matrices to reflect the bistable channels being monitored. Each logic matrix contains four normally energized matrix relays. When a coincidence isdetected, consisting of a trip inthe same Function inthe two (continued)

PALO VERDE UNITS 1.2.3 B 3.3.1-17 REVISION 27

RPS Instrumentation - Operating B 3.3.1 BASES LCO The LCO requires all instrumentation performing an RPS Function to be OPERABLE. Failure of any required portion of the instrument channel renders the affected channel(s) inoperable and reduces the reliability of the affected Functions.

Actions allow maintenance (trip channel) bypass of individual channels, but the bypass activates interlocks that prevent operation with a second channel in the same Function bypassed. With one channel in each Function trip channel bypassed, this effectively places the plant in a two-out-of-three logic configuration in those Functions.

The Qenraea,, ahYa l sl1 i D ano'N`GS't.r`ioetoop Ic t. ( .

terms is as~foilows: The calculated"l imrtinQsetDoint(LSQ) i*adterepmin~ed,.with~i~f.-the pl.a'nt.:specif~ic'-set~oint a~na:1sis fand is'b'ased.on-the'AnalvticaVLimit -and-tWTottl LOOD Uncertainty.) The UFSAR TriD-Setpoint -is"eaual .to or more conservative than the L.LSDand1i psDecified,,inthe UFSAR (Ref.- 8).JThej UFSAR TriDO'Setvoint is,the- l ia lii in.

setboint'whichxDreserves the0safety limit, and ish'-'therefore the:LS$.S:required bvJO0 CFR`.50;36..'" .The6Design Setoijt XDSb) Is the' field nsta.lled ,setti n- and evenimore

'canbe conser ativethan the UFSAR.iD-etD6iMntFThis rel~at3insh~ i'U~.Mensure that;sufWfici8ei.t8'marqin' tothe safeti andtor ianalytical ii itaisin atnta.

Only the Allowable Values (AMs),are sDecified for each RPS trir Function inthe LCO.,.. The8AV..is.cons.ide edan operabilit, li'mit:.Sfor the' chn-6l .¢Nominal trip setpoints are specified in the plant specific setpoint calculations. The nominal setpoints are selected to ensure the setpoints measured by CHANNEL FUNCTIONAL TESTS do not exceed the Allowable Value if the bistable is performing as required.

Operation with a trip setpoint less conservative than the nominal trip setpoint. but within its Allowable Value, is acceptable, provided that operation and testing are consistent with the assumDlionsof the-Wa soecif ic_

setDoi nt cal cul ations. If 60dt fis1trrunt1`tt n b

sfoind- Abe'rcAe-don n rmn stic he a°'l' e m oyiservai vewih' rD~~bt~ V a o settnci .within;.s-Lefts To0l'nce4'LALT) 6.rth:,Jinstrsunents not inq cias reawi red then thOe::

ofunct instrument channel shall be de'c16Jr'red i'n'6perrable.A channel isinoperable if its actual trip setpoint isnot within its required Allowable Value. Each Allowable Value specified ismore conservative (continued)

PALO VERDE UNITS 1.2.3 B 3.3.1-30 REVISION 25

RPS Instrumentation - Operating B 3.3.1 BASES LCO 5. Containment Pressure - High (continued)

The LCO requires four channels of Containment Pressure - High to be OPERABLE in MODES 1 and 2.

The Allowable Value is set high enough to allow for small pressure increases in containment expected during normal operation (i.e., plant heatup) and is not indicative of an abnormal condition. It is set low enough to initiate a reactor trip when an abnormal condition is indicated.

6, 7. Steam Generator Pressure - Low This LCO requires four channels of Steam Generator #1 Pressure - Low and Steam Generator #2 Pressure - Low to be OPERABLE in MODES 1 and 2.

• ~~1 . X6 MP. l;0 i..

This 44+w 4aq UFSAR.Tr Setdint is sufficiently below the Tull load operating value for steam pressure so as not to interfere with normal plant operation, but still high enough to provide the required protection in the event of excessive steam demand. Since excessive steam demand causes the RCS to cool down, resulting in positive reactivity addition to the core. If the moderator temperature coefficient is negative a reactor trip is required to offset that effect.

The trip setpoint may be manually decreased as steam generator pressure is reduced during controlled plant cooldown. provided the margin between steam generator ressure and the setpoint is maintained

• 200 psia.

This allows for controlled depressurization of the secondary system while still maintaining an active reactor trip setpoint and MSIS setpoint. until the time is reached when the setpoints are no longer needed to protect the plant. The setpoint increases automatically as steam generator pressure increases until the specified trip setpoint is reached.

footnote (aa). which is divided.into two.obarM-ts: i

,en'surecmo.Jance,with 10 CFR `50.36.in thIer-it.-that the i-nstrament set :ooi nts, atefound Inot to be o~nservyative wi't':hresDectt the-All owable Value.

Part'-reoauires^evaluation of instr.ument.oerformance or,'thecondittion where the as-found settoind for'these instrum~entsis outside its As-F 6dnd-Tolerance (AFT)

(continued)

PALO VERDE UNITS 1.2.3 B 3.3.1-34 REVISION 25

RPS Instrumentation - Operating B 3.3.1 but conservative wi~th reset t;the All~owable.Value.

Evaluatioh of instrument berformance wilverify ;that the instrument will ,c6ntnue to: behavein ac~cordance with desiqn-basi~s:;.assumotionsI. The -u~rose of the assessment.is to .ensure_.'oW _dehce'-in'h in'. strument er-formance orior to returnin :the instrument'to service. Ini tial -evaluaton wIll be D-erformed-by the techn-ician erforminci the surveildace 'who vwi1 evalu'ate -th& i nsttrp-ent,'s:abiUt.y to.nai ntal a. stable trio setooint wiJfhin the As-Left ThleranceIALTY The techniclasc- evaluatior)U!ll be re vewed-b y on shift peronnel' both-durig th"N -1a o surVii aheg fiace si~te;s .corrective actn eon- aroviram., In accordahieiwith orocedures. entry into the corrective act-ion. roaam wil]d reouire revife#farid corciebtitorif ast neesar documentathon

, of the ti: esrtha -n orndition for ooerabi 1itY. :Addibti;o ev~luation andc tentiH as-ound  ; e;ttira N de AT isevSalatWedY for- 1odg-terrw operability tnehds Pl.art -reduiresethadt the'Ys-.l& :-#ettipio nor:.the rlrstr~ument be r~eturned t&"wiyhi r~the4ALTTof t~he foeci-fired trio 1 set.ooit; d Th& s1ecifiedbfiteld hs~taliled tirio soet~oont qthe iitemed as Destn Setoolnt (D$D) and i~tieaualstQQrImore'conservat ve than the.UFSAR Tr-io Set~oint;.8 The -ieneral r onshi D nelati tamoni thePNGSi trim setoontsterms is: as f~oll~ows: The calc~ulated limlt-idna s~tooiznt '(LSP) E.i ietermi ne d`within the D1  ! ant SeCtfic SetDO; nt anas YS and isbased on the .A nal~tic&I ~Limit anc1Jotal LOODT Unce~rtainty. :The SUF$AR- 5ri DSetooi.nt is :eoua-L.-to~r more conservatpertahbntht rel'at.1ooshi' L$o)-and is soecfi:ed UFSAR ,tThe. . Ul'FSR'lT,1aoensur ;'06at o

PVNffictrhiit4 i s. ecial tp

_pihent t irt.the

_,erms:Jn i i nt setboi nt-whj ch Dreseflbes tjhe jsafbt 3 ilnt ard i s therefore the LS$S~reoutrfedL~bv,,1Q CwFR 50:.36.- The;-G52 7Ist13edfiectl 1nstalloieset t'nq a-d -cah ., be-een1,-0ore th thO than. the YUF$AR.Vr1 2$etboint- ThisU

,safety'an'd/or aalvn'altiit iXmataln"id:"I5lf the' a~s-fo~undi nstrument--s~ttina. 1s'~funcd~to be:;non ;

conservative with respect~t& the -AV 'seclifi~edwizn~the technical sTeci fications.Irithe-as-leftn P'nsItrument dettinrq-cahnot be returned.t6'- set-tinq within the ALT. oathe inist r thar..~te:`,E5 cSr6 Met. selltfi Ttl d:ahasjs thenr the 'insti'ument' channei-.shal I &be 'declaIred

inoper'able:

8. 9. Steam Generator Level - Low (continued)

PALO VERDE UNITS 1.2.3 B 3.3.1-35 REVISION 25

RPS Instrumentation - Operating B 3.3.1 BASES SURVEILLANCE SR 3.3.1.13 (continued)

REQUIREMENTS Response time may be verified by any series of sequential.

overlapping or total channel measurements, including allocated sensor response time, such that the response time is verified. Allocations for sensor response times may be obtained from the records of test results, vendor test data, or vendor engineering specifications. Topical Report CE NPSD-1167-A, "Elimination of Pressure Sensor Response Time Testing Requirements." (Ref. 12) provides the basis and methodology for using allocated sensor response times in the overall verification of the channel response time for specific sensors identified in the Topical Report.

Response time verification for other sensor types must be demonstrated by test. The allocation of sensor response times must be verified prior to placing a new component in operation and reverified after maintenance that may adversely affect the sensor response time.

A Note is added to indicate that the neutron detectors are excluded from RPS RESPONSE TIME testing because they are passive devices with minimal drift and because of the difficulty of simulating a meaningful signal. Slow changes in detector sensitivity are compensated for by performing the daily calorimetric calibration (SR 3.3.1.4)

REFERENCES 1. 10 CFR 50. Appendix A. GDC 21

2. 10 CFR 100.

3. NRC Safety Evaluation Report, July 15, 1994.

4. UFSAR, Chapter 7

5. UFSAR, Chapters 6 and 15.

6. 10 CFR 50.49.

7. "Calculation of Trip Setpoint Values, Plant Protection System". CEN-286(v), or Calculation 13-JC-SG-203 for the Low Steam Generator Pressure Trip function.

8. UFSAR. Section 7.2., Tables 7.2-1 and- 7:3-11A (continued)

PALO VERDE UNITS 1.2.3 B 3.3.1-64 REVISION 25

BASES REFERENCES 9. CEN-327. June 2. 1986. including Supplement 1.

(continued) March 3, 1989, and Calculation 13-JC-SB-200.

10. CEN-305-P. "Functional Design Requirements for a Core Protection Calculator."

11. CEN-304-P. "Functional Design Requirements for a Control Element Assembly Calculator."

12. CEOG Topical Report CE NPSD-1167-A, "Elimination of Pressure Sensor Response Time Testing Requirements."

13. CEN-323-P-A, "Reload Data Block Constant Installation Guidelines'. Combustion Engineering. Inc.. September, 1986.

14. . -FSAR':Sb'c~t o6X-n 8 , equlor Gu.

FInstrumenf S Intsi-(ReV Sio t; NoVember 1976Y PALO VERDE UNITS 1,2.3 8 3.3.1-65 REVISION 27

RPS Instrumentation - Shutdown B 3.3.2 B 3.3 INSTRUMENTATION B 3.3.2 Reactor Protective System (RPS) Instrumentation - Shutdown BASES BACKGROUND The RPS initiates a reactor trip to protect against violating the core fuel design limits and reactor coolant pressure boundary (RCPB) integrity during anticipated operational occurrences (AOOs). By tripping the reactor.

the RPS also assists the Engineered Safety Features systems in mitigating accidents.

The protection and monitoring systems have been designed to ensure safe operation of the reactor. This is achieved by specifying limiting safety system settings (LSSS) in terms of parameters directly monitored by the RPS, as well as LCOs on other reactor system parameters and equipment performance.

Ecept fdr trip Functio'ns 2 and3- 't'he LSSS. defined in this Specification as the Allowable Value. in conjunction with the LCOs. establish the threshold for protective system action to prevent exceeding acceDtable liglts durina Design Basis-Accidents For'Trip T(IBAs)-

-Functions 2 and '3.The UFSAR Trip'SetPoint is the :LSSS5?

During AOOs, which are those events expected to occur one or more times during the plant life, the acceptable limits are:

• The departure from nucleate boiling ratio shall be maintained above the Safety Limit (SL) value to prevent departure from nucleate boiling;

• Fuel centerline melting shall not occur; and

• The Reactor Coolant System pressure SL of 2750 psia shall not be exceeded.

Maintaining the parameters within the above values ensures that the offsite dose will be within the 10 CFR 50 (Ref. 1) and 10 CFR 100 (Ref. 2) criteria during AOOs.

Accidents are events that are analyzed even though they are not expected to occur during the plant life. The acceptable limit during accidents is that the offsite dose shall be maintained within an acceptable fraction of 10 CFR 100 (Ref. 2) limits. Different accident categories allow a different fraction of these limits based on probability of occurrence. Meeting the acceptable dose limit for an (continued) accident category is considered having acceptable consequences for that event.

(continued)

PALO VERDE UNITS 1,2.3 B 3.3.2-1 REVISION 0

RPS Instrumentation - Shutdown B 3.3.2 BASES LCO The LCO requires the Logarithmic Power Level - High. the Steam Generator #1 Pressure-Low. and the Steam Generator #2 Pressure-Low, RPS Functions to be OPERABLE. Failure of any required portion of the instrument channel renders the affected channel(s) inoperable and reduces the reliability of the affected Function.

Actions allow maintenance (trip channel) bypass of individual channels, but the bypass activates interlocks that prevent operation with a second channel in the same Function bypassed. With one channel in each Function trip channel bypassed. this effectively places the plant in a two-out-of-three logic configuration in those Functions.

Only the Allowable ValuesiAVs): are soecified for this RPS triD Fution in the LCO.C em an o6berabl 4ty' li-1m-it- ~fo`r -the'cha'_rihe.ljf]th as-fdun in~strument'tsettino -i's: found to.tbe eonsr.Vat1vewi th snon resoect to.;the. as-left )instrimen uothetet`tinqcannot rAV be returned to; ,sett~i~nQ within As-eLeftTo lrane(A CT). or the instrument is not. functioninqi as ,reuired--tien the gnstrument~cahnnel, shall be declared inoperable. Nomi1nal trip setpoints are specified in the plant specific setpoint calculations. The nominal setpoint is selected to ensure the setpoint measured by CHANNEL FUNCTIONAL TESTS does not exceed the Allowable Value if the bistable is performing as required. Operation with a trip setpoint less conservative than the nominal trip setpoint, but within its Allowable Value, is acceptable provided that operation and testing are consistent with the assumptions of the plant specific setpoint calculations. Each Allowable Value specified is more conservative than the analytical limit assumed in the safety analysis in order to account for instrument uncertainties appropriate to the trip Function.

These uncertainties are defined in the "Plant Protection System Selection of Trip Setpoint Values" (Ref. 4). A channel is inoperable if its actual trip setpoint is not within its required Allowable Value.

This LCO requires all four channels of the Logarithmic Power Level - High to be OPERABLE MODES in 3. 4. or 5 when the RTCBs are closed and the CEA Drive System is capable of CEA withdrawal.

A CEA is considered capable of withdrawal when power is applied to the Control Element Drive Mechanisms (CEDMs).

(continued)

PALO VERDE UNITS 1.2,3 B 3.3.2-5 REVISION 0

RPS Instrumentation - Shutdown B 3.3.2 BASES LCO that removes power from the CEDMs may be used. The CEAs are (continued) still capable of withdrawal if the CEDMCS withdrawal circuits are disabled with power applied to the CEDMs because failures in the CEDMCS could result in CEA withdrawal.

This LCO requires all four channels of Steam Generator #1 Pressure-Low, and Steam Generator #2 Pressure-Low, to be OPERABLE in MODE 3, when the RTCBs are closed and the CEA Drive System is capable of CEA withdrawal. These RPS functions are not required in MODES 4 and 5 because the Steam Generator temperature is low, therefore the energy release and resulting cooldown following a large MSLB in MODES 4 and 5 is not significant.

F6'totene (e) .. wnhjchsdi vided into tWo -Darts.'well shure comDl iancewiWth IoQ-CFR 50.36 in the;event that'Ithe, instrument< iset' Doints",a're.foundnotwtote conservativie wth resDectntohe AllNowable 'Plu . Part 'l,'re ui.res ev'a6u1ti of-instrument, performancefo'rthe 'condition'.',here the a'-s-found settina instr'uments tfirth-ese i.s itsd-its.'As'-'Found Toler-nce (AFT) bu'tnser'vative-witresect to.the Allowabl e-.Value'._ tEv a- l:u'&ttion of instrdtim-ei't; performanmce1wiill verfifiyth-t.thetriJnstrbme'6t wil continue1 to behave in accQrth.d:ance '.i1n des iqn-basis assunimDtions'.. Theur0ose-of,

{t~be ass e,~s~sre st-istoensure',confide. i n tbe' intume~nt_

verformance orii the 'in'stumen~t t-ttreturnivn tQ-ervice hiitial:'valuatio~twiil :be Doerformedvbyr the techri'cian 6erformihnl.the'sbir sQ veilane 1-e;a:evauatewhlol tne instrumiient sabilitY to'C intain 'a stabletrio" setDboint within the As-Left'Tol erance :.(ALT)I, The-'techniciians evaluation willb-,?t,,e reviewedby,on ishift Deronnel both curinithe aor'ov'al ofthe' surve1llanh'cedata ndas a resblt ofienvyof the'dev ivtii n in the site s:crrectie action'- 4oaram-.-., 'InLaccord6 nce ith orocedurses; entry intb the correctivYer act :in broram wi 1 readi'u e'view adn focumbntktjon of the qoniition, for o'oerwabiiitvt 'AXtonal evaluation . Dotential corre,7tive actionsat"peessarv ki1l ensur.qKt-t any as-foutxf settin found 'outsi de the'AIT 5

9is. eval2u7ted4l-ng-term operabi -itytrends Pa r i'eQui tt,&t,"the:as 1'eft setti e,' res that- 44i 6struaent ithi'n 'the ,LT1 f the5.svecified trio f'ireturn edto' setooint.-'The' specified field i nstalled triD s'et0o-nt'.'

ter~'ed' te ;Setbnoint (Oi) andi;s eoua; St'Desn .to'o mr'.

conservative, than 'the UFSAR T-ri Setl;.61nt The' eneral relationshi, amonb_.the PVNGS tri, :setooint terms, i.s-as follows: The ^calculattd limi ti nci' setoint tLSP)is determined within the Dlant sDecific setr~oint 'analysis and is based oncthe.-Analytical Limit and Total Loop (continued)

B 3.3.2-6 REVISION 15 PALO PALO VERDE UNITS 1.2.3 VERDE UNITS 1.2.3 B 3.3.2-6 REVISION 15

RPS Instrumentation - Shutdown B 3.3.2 BASES Uncertaintv.l The FUFSAR TriSetooi nts -eualto p_r more conserVatv-ve -thah the: LSD and iis'secified-iti-the UFSAR The UFSAR:-TriD Setooint'is the lqa1 limit-ir1qetpQent which rese~r-ves^the safety -lmit anddishreorertthe LSSS reouifred bN-401CMR 50.36 J.heSSDfisth fteld~ instal;ed t ett;i-nq an an e vndr ecbnservativecthapth: USA

~fribS~tpoht~

Tri Th'i ' tr:tionshD M~t2Ca J noure~ bt~uf ih marqi n to the safe andV/ir anaJYtic tli--.rjhy .,,I i~mitisat IfCthe -as-found instrumentsettj nqqis7ound tq-be non; conservativelwith res oect to.- the 'AV.s-AcVfied ri.th, .

technical specifications, -or the' as-leftinstrumentsettjn cannot be' returned ito -a'sett inwithi. thelALj- orthe instrument is not functionino Hes re`uired,:,then t instrument channel shall be declared inoperablbt.

The Allowable Values are high enough to provide an operating envelope that prevents unnecessary Logarithmic Power Level - High reactor trips during normal plant operations.

The Allowable Values are low enough for the system to maintain a safety margin for unacceptable fuel cladding damage should a CEA withdrawal or MSLB event occur.

The Logarithmic Power Level - High trip may be bypassed when logarithmic power is above 1E-4% NRTP to allow the reactor to be brought to power during a reactor startup. This bypass is automatically removed when logarithmic power decreases below 1E-4% NRTP. Above 1E-4% NRTP. the Variable Over Power - High and Pressurizer Pressure - High trips provide protection for reactivity transients.

The automatic bypass removal channel is INOPERABLE when the associated Log power channel has failed. The bypass function is manually controlled via station operating procedures and the bypass removal circuitry itself is fully capable of responding to a change in the associated input bistable.

Footnotes (a)and (b)in Table 3.3.1-1 and (d)in Table 3.3.2-1 clearly require an "automatic" removal of trip bypasses. A failed Log channel may prevent, depending on the failure mode, the associated input bistable from changing state as power transitions through the automatic bypass removal setpoint. Specifically, when the indicated Log power channel is failed high (above 1E-4%). the automatic Hi-Log power trip bypass removal feature in that channel cannot function. Similarly, when the indicated Log power channel is failed low (below IE-4%). the automatic DNBR-LPD trip bypass removal feature in that channel cannot function. Although one bypass removal feature is applicable above 1E-4% NRTP and (continued)

PALO VERDE UNITS 1,2.3 B 3.3.2-6 REVISION 15

RPS Instrumentation - Shutdown B 3.3.2 BASES A Note is added to indicate that the neutron detectors are excluded from RPS RESPONSE TIME testing because they are passive devices with minimal drift and because of the difficulty of simulating a meaningful signal. Slow changes in detector sensitivity are compensated for by performing the daily calorimetric calibration (SR 3.3.1.4).

REFERENCES 1. 10 CFR 50.

2. 10 CFR 100.

3. UFSAR. Section 7.2. '-Tabl~es,7:,-` ad 7.311A

4. "Calculation of Trip Setpoint Values Plant Protection System. CEN-286(v)". or Calculation 13-JC-SG-203 for the Low Steam Generator Pressure Trip Function.

5. NRC Safety Evaluation Report. July 15. 1994.

6. CEN-327. June 2. 1986. including Supplement 1, March 3. 1989. and Calculation 13-JC-SB-200.

7. CEOG Topical Report CE NPSD-1167-A. "Elimination of Pressure Sensor Response Time Testing Requirements."

PALO VERDE UNITS 1.2.3 B 3.3.2-17 REVISION 15

ESFAS Instrumentation B 3.3.5 BASES BACKGROUND Bistable Trip Units (continued)

The trip setpoints and Allowable Values used in the bistables are based on the analytical limits stated in Reference 5. The selection of these trip setpoints is such that adequate protection is provided when all sensor and processing time delays are taken into account. To allow for calibration tolerances, instrumentation uncertainties.

instrument drift, and severe environment effects, for those ESFAS channels that must function in harsh environments as defined by 10 CFR 50.49 (Ref. 6). ExceptiCfo TrpUnc'tions 4aand 4b Allowable Vaiue.s eciiedJn Tajble 3.3.5-L1 in the ajc~aomoalryi nq LCO. andFSAR T Detpoints.eci fie'in Table- 7`.3- of the tSR-(R~f'.8- .fr.r Fu~c~hs4 and 4 are conservatively aju0sted wisth reDect to the anal,ytlcalI limits. 1The6-IFSART e~it'aeased._ri the calculated totadV l'oo-puncertkaintyvcosistent with'the methodoloa as doc umented in'thle'UFSAR-(RG 1.1-05-.:-ReViMsi'n 1:November'-1976) (Ref.11)...[e Qenera l elationshiD I among the PVNGS-trli. setvoint ter'mssisas 'follows, he caiculated LimingSeoit(S .b deterMhned-wlthnn rthe -lant soeci-fc:setDonto al vsi> and is based On th&Analytic 1 L'imit->and the T t~al.L~o&D;Un'ce'rtainrtYK'." ,Th&UESAR Trilp.,

soqa I is fmtjiq.

.SetoDoi:ntS 5 -eualtb oi.twicbree~s.h

,fo. s A~afet1mcnd

' mope eors'ervtftiv.'~th~n."t-he~fLS:&:'

S 'SDeCi fled 'in -s~the U: SAL T A to in th L- : it'.,

.- j,,an

'~ he'.: .,

t..,,, n ..

,,E,  !. el t

,' '", ' t'E, : '.;' S';

and;.,i5,'t~herefore Athe-L'SSS-.r.eogui re~d.b~1O S ThSl:,^.3F ses.

Desion Set~oont ;(DSp) Us'itlefi;.eld 1install1edisettih&and:.can be even.mor~e onser vat orethan.the UFSAR. T1rye ettoint;.

Thi~s,'re~lationshio hs.rens~heth'at-s'uff~icientimar~in to'. the safety li~m'it isma'inta'i'ned. b'A detailed description ot the methodology used to calculate the trip setpoints. including their explicit uncertainties, is provided in the "Plant Protection System S~electi~o~nof..T~r~ioDSe.&oint Yaiu~es2 (Ref.

7). The actual 'n, om trSeAp esign SetPoint (DSP) entered into theteis more estill conservative than b Allowable Value to account for changesbinr measurement errors detectable by a CHANNEL FUNCTIONAL TEST. A channel isinoperable if its actual trip setpoint isnot within its required Allowable Value.

Setpoints in accordance with the Allowable Value will ensure that Safety Limits of LCO Section 2.0. "Safety Limits." are not violated during AOOs and the consequences of Design Basis Accidents (uBAs) will be acceptable. providing the (continued)

PALO VERDE UNITS 1.2.3 B 3.3.5-4 REVISION 0

ESFAS Instrumentation B 3.3.5 BASES LCO Bypass Removal (continued)

This LCO applies to the operating bypass removal feature only. If the operating bypass enable function is failed so as to prevent entering a operating bypass condition, operation may continue. Because the trip setpoint has a floor value of 100 psia. a channel trip will result if pressure is decreased below this setpoint without ypassing.

The operating bypass removal Allowable Value was chosen because MSLB events originating from below this setpoint add less positive reactivity than that which can be compensated for by required SDM.

4. Main Steam Isolation Signal The LCO is applicable to the MSIS in MODES 1. 2 and 3 except when all associated valves are closed.

a. Steam Generator Pressure - Low This LCO requires four channels of Steam Generator Pressure - Low to be OPERABLE in MODES 1. 2 and 3.

The N4;bi6 4 UFS-AR'Trip Setrpoint for this trip is set below the full load operating value for steam pressure so as not to interfere with normal plant operation. However, the setting is high enough to provide an MSIS (Function 4) during an excessive steam demand event. An excessive steam demand event causes the RCS to cool down.

resulting in a positive reactivity addition to the core.

MSIS limits this cooldown by isolating both steam generators if the pressure in either drops below the trip setpoint. An RPS trip on Steam Generator Pressure - Low is initiated simultaneously. using the same bistable.

(continued)

PALO VERDE UNITS 1.2.3 B 3.3.5-15 REVISION 0

ESFAS Instrumentation B 3.3.5 BASES LCO a. Steam Generator Pressure - Low (continued)

The Steam Generator Pressure - Low trip setpoint may be manually decreased as steam generator pressure is reduced. This prevents an RPS trip or MSIS actuation during controlled plant cooldown. The margin between actual steam generator pressure and the trip setpoint must be maintained less than or equal to the specified value of 200 psia to ensure a reactor trip and MSIS will occur when required.

Foot"oht(d)'.-wi.ch isdivided into',two-DartsS.

wi.ll,.:ensure: comDiJ ance'hwth10 'CFR 5O346in th~

eve nir ument set DoiftS are,,,..gund -not Itsabtrthe, to b"c'onservatiVe'"'th respect. f'totthe A16oWab'le rni.,5X~urment 6t:ueid&,nP rt.12.rebuifres-'ev. .,iat.

bdrforbahn,. for the condiltii66mhere Ath&`6as-foiuhd Seft 6inq-Po&these instrum6ents Is out6si-.de'6 its As-Fou n',Td'ol~ertce- (AFT) but.conservativewi,'

'rbes'ectt.o-th'.-'All ow-able-Value:. Eval uat.1on.of anstrument De'rf6rmance wi 1I-verift hattihe= ,

Instrument'wil.l continue to behav~e ip;accordance-with.~desiqn-,biasi's.,a~ssumsti'onls, 5LT^h'e rD-'oie.'of the assessment ise tol ensure' onfide.e=ii the-instrument,Derfor~mance.sr~i'or,.to+.r.et-UMrfiina- the.,.,

ins'trumment to service. Initi-evaluation .will 'e DerTformed by the tfechnIc an 'erformina:the surveil`ance.wh.o.;-`'i-l evaluate the instrunent',s abilllty toi'nmai'n't~ija ~'-sta'blve tsrio t~:tont :wi~thTin the As-j.~eft:Tolean'ce (ALT). e techniian's eval'uati'on will be,.r`evewed,'b~v`'on hft ersone bothW i.Thii the aDorovalif.the survei-llanceIdata and .,a~. -r~sultofen~tryof the'devi'at o nr-,rhthe6 s crt t'tv' action, Droarau;,

r r _ ,acordance.

With brocedur es-.,entravinto th'!.ttectiveiact1io6 proaram wi 1 reo ure :'rbV.i',and do'umentatf'nt'-o-,f the condition for ooerabl ivy;' Additional evalha~t'iior and potential corrective ,ctlbn as nefessa rywildl`'ensure that any asL~nd'settind found otide' theAFr is'evaluatedior long-term operbi 1t1t~2trends.-

Pkr 2 ,-roui res. t-hat- the as-l eft .sttln - -=fr 'the inst~rume.nt bereturoed tok within -. thetALT off.the

'.'tribo.'Setbo 1ft. .The:, soDec.ifi'ed-field soecfjie'd installed trip se tpoint istermed as, the Desag'n (continued)

PALO VERDE UNITS 1.2,3 B 3.3.5-16 REVISION 0

ESFAS Instrumentation B 3.3.5 BASES

$etD6ihnt (DSD and' is edual to'or more conservative-th'an .'th&'-UFSARw TriDpS'etDoint- The 0enera, ,relationshiD.amorc 0the:PVNG5:tr'ipisetbodint

'terms is as foIo ws The calculated limitinci setDoi nt LS ) is-determined within the plant sdoecific'setDoint anal-Ysis' and i's'Sbased on Ahe Analytical Lim'i t and Total.L OO Uncertainty". .The UFSAR.4Tr1io0.Set oint i~s eaual to or more conservative than'.th eLSo 1and'is., sDecified.id the FUSAR$tlih6e UFSAR- Trip-Set6'oi n-s_1 t7he leoal E ti '

ha oint, whi ch r ser t ndee'4D$1is.the.t

, ,ei.ef8vcorn!e so r field rtv itnsta-lid.'s LS a , Va. ettkiinand' s 46a, .r.-eIf.RgS z~ O :be86 pven- uiore, cot6S~rVatjiVe:than 'te FARTr Set~lft Tis, elationshio nspeta

'suffi,,ci ent:,nmar.intothe; safety6and/or.ana l t-ica lTimitismaintained,i';If the as-found inst'rument sett ifcr is...found;to,be non.-con-servati'vewith resoect to the'AV sDecifi'e'd i'n the technicak

'soe~cflfcat'ions.  !'or the ,as-left 'iinstrumentsettinci c~annot be returned to a settinci withih, the ALT. or the instrum'ent'is notjfunctiohnin -as readured'.

then' ,the'istrument ch'annel.1.shall.;be:-dec;laredd Thoperabl e,.,

b. Containment Pressure - High This LCO requires four channels of Containment Pressure - High to be OPERABLE in MODES 1. 2 and

3. The Containment Pressure - High signal is shared among the SIAS (Function 1), CIAS (Function 3). and MSIS (Function 4).

The Allowable Value for this trip isset high enough to allow for small pressure increases in containment expected during normal operation (i.e., plant heatup) and isnot indicative of an abnormal condition. The setting is low enough to initiate the ESF Functions when an abnormal condition isindicated. This allows the ESF systems to perform as expected inthe accident analyses to mitigate the consequences of the analyzed accidents.

c. Steam Generator Level-High (continued)

PALO VERDE UNITS 1.2.3 8 3.3.5-16 REVISION 0

ESFAS Instrumentation B 3.3.5 BASES REFERENCES 1. UFSAR, Section 7.3.

2. 10 CFR 50, Appendix A.

3. NRC Safety Evaluation Report. July 15, 1994

4. IEEE Standard 279-1971.

5. UFSAR, Chapter 15.

6. 10 CFR 50.49.

7. "Calculation of Trip Setpoint Valves Plant Protection System", CEN-286(v), or Calculation 13-JC-SG-203 for the Low Steam Generator Pressure Trip Function.

8. UFSAR, Section 7.2., Tablesn7.2-1land^-;3-11A

9. CEN-327, May 1986. including Supplement 1. March 1989, I

and Calculation 13-JC-SB-200.

10. CEOG Topical Report CE NPSD-1167-A. "Elimination of Pressure Sensor Response Time Testing Requirements." I 11.i UFSAR'Secfi~orn;8.'Reaul~a YfG.uid& 1.105a

'Instrtment Setpoinfs (Revlsion 1,;Novembe 1976e."

PALO VERDE UNITS 1,2.3 B 3.3.5-29 REVISION 10