ML20077M086

Nonproprietary TS Improvement Analysis for RPS for PBAPS, Units 2 & 3

ML20077M086
Person / Time
Site:	Peach Bottom
Issue date:	01/31/1995
From:	Chi L, Jo Jacobs, Sozzi G GENERAL ELECTRIC CO.
To:
Shared Package
ML20077M083	List: ML20077M081 ML20077M086 ML20077M095
References
MDE-87-0485-1-N, MDE-87-0485-1-NP, MDE-87-485-1-N, MDE-87-485-1-NP, NUDOCS 9501120144
Download: ML20077M086 (34)

Text

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f3 MDE-87-0485-1-NP DRF A0042-02119-D/

DRF C71-00102 January 1995 9

TECHNICAL SPECIFICATION IMPROVEMENT ANALYSIS FOR THE REACTOR PROTECTION SYSTEM FOR PEACH BOTTOM ATOMIC POWER STATION,. UNITS 2 AND 3 i

(THIS REPORT HAS BEEN PREPARED FOR PHILADELPHIA ELECTRIC COMPANY THROUGH THE TECHNICAL SPECIFICATION IMPROVEMENT COMMITTEE OF THE BUR OWNERS' CROUP)

PREPARED BY:

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J.t'. Jacobs?'Enginesr Application Engineering Services VERIFIED BY:

L.L. Chi, Senior Engineer Application Engineering Services l

APPROVED BY:

'A G.L. Sozz'i, MaMger Application Engineering Services i

$D$c o!0$0077 GENERAL h ELECTRIC

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TABLE OF CONTENTS i

g 1.

' INTRODUCTION 1

2.

EVALUATION METHOD 2

3.

RESULTS OF RPS EVALUATION 4

4

SUMMARY

AND CONCLUSIONS 9-5.

REFERENCES 10 i

APPENDIX A: RPS EVALUATION FOR PEACH BOTTOM ATOMIC POWER-STATION.

UNITS 2 AND 3

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1.

INTRODUCTION This report extends the generic study of modifying the technical' specification requirements of the Reactor Protection System (RPS) on a plant specific basis for Peach ~ Bottom Atomic Power Station, Units 2 and 3 (PBAPS),

The generic study (Reference -1) provides a technical -

basis to modify tbc surveillance test frequencies and allowable out-ef-service ricer of the - RPS f rom the generic technical

[

specifications. The generic study also provides additional analyses of.various known different RPS configurations to support the applica-tion of the generic basis on a plant specific basis. The generic basis and the supporting analyses were utilized in this plant specific evaluation. The results of the plant specific evaluation for PBAPS are presented herein.

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General Electric Company MDE-87-0485-1 NP 2.

EVALL'ATION METHOD' The plant specific evaluation of the modification of the surveillance test f requencies and allowable out-of-service time of the RPS was performed in the following steps:

a.

Cather plant specific infomation on the RPS from Philadelphia Electric Company (PECO).

The info rmation includes the following:

(1)

Elementary Diagram of the RPS and related systems.

(2)

RPS description such as plant Final Safety Analysis Report (FSAR).

(3) Technical specifications on the RPS.

(4)

RPS surveillance test procedures.

The latest revision of Items 1,2 and 3 above were supplied by PECO.

Item 4 above was provided by PECO in the form of a questionnaire identifying the differences between the procedure used in the generic evaluation and the procedure used at PBAPS.

Section I of the checklist in Appendix A was used to identify the data source of the plant specific information.

b.

Construct the plant specific RPS configuration from the plant specific information.

Questions "A"

through "H" in Section II of the checklist were used for this process.

i c.

Compare the plant specific RPS configuration with the generic RPS configuration using the generic RPS elementary l

diagram, RPS description, technical specification require-

ments, and other generic inputs.

Section III of the checklist was used for this process..

J General Electric Company 1

MDE-87-0485-1 NP l

d.

Classify the differences-into three categories:

(1) Ob'vious items which have no effect on the reliability of the RPS.

Examples of these "no effect" items are component ~ name differences, symbol differences, and other minor non-functional differences.

Disposition.of the obvious "no effect" items does not require addi-

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tional analysis.

(2) Potential differences which' require considerable engineering judgment for disposition becaute of the functions,1 differences.

Examples of thes" potential differences are separate channels for manaal scram as opposed to non-separate channel in tM generic plant and dual redundant contacts per sensor relay in the applicable trip channels as opposed to a single set of i

contacts in the generic plant.

The disposition of such items would require engineering assessment as shown in -

i Appendix K of Reference 1.

(3)

Potential differences which require additional analyses to evaluate the effect on the RPS reliability.

Examples of such potential differences are using HTA relays as opposed to using both Potter and Brumfield relays and Agastat relays in the generic evaluation.

Disposition of these items would require additional analyses to compare with the generic results.

These analyses are documented in Reference 1.

e.

Compile a list of plant specific differences of Category (2) and (3).

f.

Assess the reliability effect of the differences identified in Step (e) on the generic results. The results of the assessment are documented in Section III of the checklist.

g.

Document the results of the plant specific evaluation.

The above seven step process is documented in Appendix A of this report. 1

i General Electris Company MDE-87-0485-1-NP -

3.

RESUI.TS OF RPS EVALUATION -

-The results of the plant specific evaluation of the RPS for PBAPS are documented in Appendix A of. this report.

The results show that the RPS configuration of PBAPS has the following dif ferences which are.

classified Category (2) or (3):

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4 SLW.ARY AND CONCLUSIONS A plant specific evaluation of modifying the ' surveillance test fre-quencies and allowable out-of-service time of the RPS from the techni-i cal specifications of PBAPS has been performed. The evaluatiet.

i utilized the generic basis and the additional analyses documented in Reference 1.

The results indicated that the RPS - configuration ' for PBAPS has several differences compared to the RPS configuration in the generic evaluation.

These differences and the assessment of their-effects on the RPS failure frequency are shown in Appendix A.

The analysis reported in Reference 1 shows tnat these differences would

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not significatly affect the improvement in plant safety due to the i

changes in the technical specifications based on the generic analysis.

Therefore, the generic analysis in Reference 1 is applicable to PBAPS.

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REFERENCES-a C f

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" Technical-Specification improvement Analyses-for BtTR-Reactor Protection System," ' Ge ne ra l-.-

Electric-Company, l

NEDC-30851P. May 1985.

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- General Electric Company MDE-87-0485-1-NP APPENDIX A RPS EVALUATION CHECKLIST FOR PEACH BOTTOM ATOMIC P0k'ER STATION, UNITS 2 AND 3 I

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General Electric Company MDE-87-0485-1-NP Section I - RPS Plant Specific Data Source Utf *.ity: Philadelphia-Electric Company Plant:

Peach Bottom Atomic Power Station. Units 2 and 3 Source l

Number 1.

RPS Elementary 6280-M S-54, sh.1-21, Rev.61 1

2.

RPS'IED 6280-M-1-T-49, sh.1-3, Rev.3 l

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3.

RPS MG Set Control Systen Elementary 6280-E12-1, Rev.8 4

RPS Interconnection Scheme Elementary E-354, sh.1 42 Rev.24 e

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RPS Design Specification Not available i

6.

FSAR Section 7.2, Rev.1, Jan.1983 7.

Technical Specifications Section'4.1, 6/21/84 8.

Surveillance Test Procedure' Checklist EDT BOA-8513 9.

Others Telcon H.F. Hansell to L.L. Chi, 2/26/85 l

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( c, MDE-87-0485-1-NP Section II - RPS Configuration Data Data

• I A.

RPS System Data Source

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4 1.

Number of trip systems 2

(2)-

2.

Number of logic channels per trip system For Automatic Scram 2

(2)

For Manual Scram 1

(2) 3.

Power supply source for each channel HG Set-(2) 4.

Operation mode

- De-energize to trip Yes (2) 1 5.

. Logic arrangement 1

- one-out-of-two twice Yes (2)

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6.

Electrical Protection Assemblies (EPAs)

Yes (9) 7.

Design requirement IEEE-279.(7) 1 I

• The numbers shown in the Data Source column refer to the documents listed in Section I.

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.Section II - RPS Configuration Data B.

RPS Sensors l.

Identify the type, total number, and number per RPS channel for the following RPS sensors.

Total Number /

Data g

Number RPS Channel-Source

- APRM Analog 6( }

2 (1)

- Turbine Stop I

2 II'2)

Valve Switch 8

- Turbine Control Valve Switch 4

1 (1,2)

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- MSIV Position Switch 8

4 (1,2) r

- MSL Radiation Gamma 4

1

-(1) '

Detector

- Level 8 (High l

Water Level)

N/A N/A N/A-N/A'

- Level 3 (Lov Water Level)

Analog 4

1 (1,2)

-- SDV Level Type 1 (Analog)

Switch A 2

1 (1,2)

Type 2 Switch B(3) 2 1

(1,2)

- High Reactor Pressure Analog 4

1 (1,2)

- High Drywell Pressure Analog 4

1 (1,2) j

- Manual Trip Switch 2

1( }

(1)

- Mode Switch Trip switch 1

1(4)

(1)

- Low Condenser Vacuum Analog 4

1 (1,7)

(1) Two shared between channels.

(2) Four switches, double pole - single throw.

.(3) Unit 3 has, in addition, Failed Instrumentation Trip.

(4) One per manual channel, i.e.,

one per trip system.

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I General Electric Company MDE-87-0485-1-NP Section II - RPS Configuration Data Data

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B.

RPS Sensors (Cont'd)

Source 2.

Turbine Stop Valve closure logic arrangement Closure of 3 out of 4 valves initiates scram (1,6) 3.

Turbine Stop Valve closure monitoring Position switches (2) 4.

Turbine Control Valve fast closure monitoring 011 Pressure Switches (2) 5.

MSIV closure logic arrangement Isolation of 3 out of 4 steam lines initiates scram (1.6) 6.

Diversity in SDV level sensors Unit 2 - Switches by different vendors (2.6)

Unit 3 - Thermal diffusivity + float switches 7.

Number of MSL 4

(1) 8.

List of available bypasses (1)

IRM Trip Bypass Yes Noncoincident Neutron Monitoring System Trip Bypass Yes RPV High Water Level RPS Trip Bypass Not Applicable Turbine Stop Valve RPS Trip Bypass Yes Turbine Control Valve RPS Trip Bypass Yes MSIV Closure RPS Trip Bypass Yes SDV High Water Level Trip Bypass Yes Reactor Mode Switch " Shutdown" mode i

Trip Bypass Yes Low Condenser Vacuum Yes j

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Section II - RPS Configuration Data Data C.

Sensor Relavs Data Source 1.

Types of relays GE Type HPA (1):

i 2.

Number of pairs of contacts per relay in the trip channel 2

(1) 3.

List type of relay for each RPS sensor (1) i l

Potter &

Brumfield Anastat HEA CR105 i

-1 APRM s

x-i Turbine Stop Valve x

Turbine Control Valve x

MSIV Position x

MSL Radiation x

I Level 3 x

SDV Level x

Type 1 (Switch A) x TYPE 2 (Switch B) x High Reactor pressure x-High Drywell Pressure x

Manual Trip x

Mode Switch Trip x

Low Condenser Vacuum x

Level 8 N/A PBAPS uses Agastat relays for trip signals from the ATU A-6

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General Electric Company MDE-87-0485-1-NP i

Section II - RPS Configuration Data l

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I Data D.

Scrae Contactors Data Source f

1.

Type of scram contactors CE Type CR105 (1) 2.

Total number of scram contactors 8*

(1) 3.

Number of scram contactors per channel 2

(1)

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• The above 8 scram contactors are for the auto trip systems only.

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The manual scram channels have their own scram contactors (total

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of 4 contactors with 2 per channel).

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.I Sectien II RPS Configuration Data.

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Air Pilot Solenoid Valves Da t a.

Source

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Number of solenoid valves per control rod drive 2

(2) i 2.-

-Number of solenoid operators per valve 1

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Section II - RPS Configuration Data Data

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Backup Scram Data Source 1.

Type of scram contactors for backup scram valves GE Type CR105 (1) 2.

Number of scram contactors per backup scram valve 6

(1) t 3.

Same RPS scram contactors are used to actuate backup scram valves Yes (11~

4.

Operator mode

- energized to trip Yes

.(1) l i

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Test requirement for backup scram valves Not specified in Tech. Spec.

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Section II - RPS Configuration Data I

s Data C.

RPS Tech. Soec. Requirements Source i

1.

Calibration Frequency for LPRM Once every six weeks (7) 2.

Calibration frequency for trip units.

Not stated

-(7) 3.

Frequency of Logic System Functional Tests Once per 18 months (7) 4.

Allowable time to place an inoperable channel or trip system in the tripped conditions when the number of operable channels is less than the required minimum operable channels per trip system.

Immediately (7) 5.

Exception to Item 4 Tech Spec does not specify exception (7) 6.

Allowable time to place a trip system in the tripped t

conditions when the number of operable channels is less than the required minimus operable channels for both trip systems.

Immediately (7) 7.

Exception to Item 6 due to surveillance test.

Eight hours (7) 8.

Complete the Table on the following page.

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General Electnc Company MDE-87-0485-1-NP REACTOR PROTECTION SYSTEM INSTRUMENTATION REQlllRe.

Channe1 Minimum Channel Functional Channel Operable Channels Check Test Calibration Per Trip System Generic Plant Generic Plant Generic Plant Ceneric Plant Functional Unit Model Specific Model Specific Model Specific Model Specific

1. Average Power Range Monitor:

a. Flow Biased Simulated S.D N/A S/U,W N/A W.SA.R N/A 3

N/A Thermal Power - High

b. Neutron Flux - High S

N/A S/U,W W

W.SA 2/W 3

2

c. Inoperative N/A N/A W

W N/A N/A 3

2

2. Reactor Vessei Steam Dome S

D M

M R

OC

'2 2

Pressure - High

3. Reactor Vessel Water Level -

S D

H H

R OC 2

2 Low, Level 3

4. Reactor Vessel Water Level -

S N/A M

N/A R

N/A 2

N/A High Level 8

5. Main Sceae Line Isolation N/A N/A M

M R

R 4'

4 Valve - Closure

6. Main Steam Line Radiation.-

S N/A M

W R

Q.

2 2

High

7. Drywell Pressure - High S

D M

M R

OC 2

2

8. Main Condenser Vacuum - Low N/A D

N/A M

N/A OC N/A 2

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General Electnc Company MDE-87-0485-1-NP REACTOR PROTECTION SYSTEM INSTRUMENTATION RFQUIREMENTS Channel Minimum Channel Functional Channel Operable Channels Check Test Callbration Per Trip System Generic Plant Generic Plant Generic Plant Generic Plant

'e:ct ional linit Model Specific Model Specific Model Specific

.l'odel SpectIlr Scroa Discharge Volume Water 1.cvel - High Typ2 1 - Switch A S

N/A M

M R

R 2

2 Typa 2 - Switch B N/A N/A M

M R

R 2

2 id. Turbine Stop Valve - Closure N/A N/A M

M R

R 4

4

11. Turbine Control Valve Fast N/A N/A M

M R

OC 2.

2 Clo2xre Valve Trip Systen Oil Precs:ure - Low

)2. Rzector Mode Switch N/A N/A R

R N/A N/A 2

1 Shutdown Position

]3. Manus! Scram N/A N/A M

Q N/A N/A 2

i S-Shift M-Monthly S/U=Startup D-Dmily Q-Quarterly N/A=Not Applicable W-Weekly R= Refueling Outage DC = Operating Cycle A-12

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General Electric Company MDE-874185-1-NP Sectien-II - RPS Configuration Data (Cont'd)

Data H.

RPS Surveillance Tests Procedure Source g

1.

The following components are all tested as part (8) of an individual channel functional test:

Individual channel sensor (s),

e.g., Transmitters a.

and Trip Units, switches, flux or radiation

sensors, b.

Associated logic relay (s) c.

Associated scram contactors List any plant specific differences from the above.

t

RESPONSE

For 1.a. above, the signal is injected as close to transmitter as possible.

2.

When an individual sensor channel is in test or repair, (8) is associated logic channel tripped or is the sensor channel jumpered? State which of the two conditions applies to your plant.

If any other condition exists in your plant, describe.

RESPONSE

Logic channel is tripped.

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General Electric Company MDE-87-0485-1-NP Section II - RPS Configuration Data (Cont'd)

I Data H.

RPS Surveillance Tests Procedure (Cont'd)

Source 3.

For those plants which do not place individual channels (8) in a tripped condition during test or repair, it is assumed in the CE analysis that only the individual l

sensor and associated logic relay is placed in an inoperable condition during test or repair of the individual channel.

If this assumption is not true for your plant, list the components (from sensor to scram contactors) which are placed in inoperable condition during test or repair.

RESPONSE

f This assumption is true for PBAPS.

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l 4.

The following number of individual scram (8) contactor actuations are assumed in the GE analyses for each channel functional test:

a. APRM channel functional tes.s -

2 actuations per scram cor.cactor pair in each trip logic channel.

b. MSIV closure channel function tests -

4 actuations per scram contactor i

pair in each trip logic channel.

I

c. Other channel functional tests -

I actuation per scram contactor pair in each trip logic channel.

r List any differences from the above for your specific pleat.

1

RESPONSE

No difference.

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General Elecuic Company MDE-87-0485-1-NP Section II - RPS Configuration Data (Cont'd) i i

Data H.

RPS Surveillance Tests Procedure (Cont'd)

Source

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5.

Do plant procedures allow simultaneous (8) inoperable conditions (failed condition) of diverse sensors in a given logic channel?

RESPONSE

Yes, provided conditions satisfy Technical Specification requirements.

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s General Electric Company MDE-87-0485-1-NP Section III - Assessed Reliability Effect of RPS Configuration Differences Plant Specific Assessed Reliability Bk'R Generic Model Difference Effect A.

RPS System e

1.

Generic model has No difference i

two trip systems.

5 2.

Generic model has No difference two logic channels I

per trip system for automatic scram.

L 3.

During operation, No difference the trip systems are energized and trip when de-energized.

4 The RPS logic is one-No difference out-of-two twice, i.e.,

one out of two logic channels will trip an individual system and trip of both systems is required for s, ram.

c 5.

Generic model has No difference Electrical Protection Assemblies (EPAs).

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Gener:d Elm:tnc Company MDE-87-0485-1-NP I

Section III - Assessed Reliability.Effect of RPS Configuration Differences l

Plant Sp2cific Assessed Reliability I

BWR Generic Model Difference Effect

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6.

Each RFS channel can be Separate channel for manually tripped from manual scram, but each i

the Control Room using auto-scram channel can I

the manual scram also be manually tripped i

circuits.

by interrupting the power to the RPS.

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Sensors l

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Generic model has No difference Analog Trip Unit /

Transmitter for pressure and level sensors.

)

2.

Minimum number of No difference sensors is one per i

RPS channel for each scram variable.

3.

Generic model has Six APRM monitors with eight APRM monitors two monitors shared by with two per RPS two channels.

l channel.

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Section III - Assessed Reliability Effect of k/S Configuration Differences Plant Specific Assessed Reliability BWK Generic Model Difference Effect i

3.

4 Stop Valve Closure No difference trip logic is a reduced two-of-four i

required for trip.

5.

Stop Valve closure is No difference monitored by limit switches.

6.

Turbine Control Valve No difference fast closure is monitored by control oil pressure.

i 7.

MSIV closure trip No difference

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logic requires isolation of three j

out of four steam-lines to scram.

8.

Generic model has a No Level 8 trip Level 8 (High Reactor i

Water Level) Trip.

9.

Generic model has Different type of switches diverse Scram Dis-are used to provide divers-charge Volume (SDV) ity.

level sensors.

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10.

Generic model has No difference 4 main steamlines' i

11.

Generic model does Plant has a direct scram not have a direct on low condenser vacuum.

scrse on low condenser vacuum.

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MDE 87-0485-1-NP Section III - Assessed Reliability Effect of RPS Configuration Differences Plant Specific

. Assessed Reliability l

BWR Generic Model Difference Effect C.

Sensor Relays t

1.

For all transients All scram variables have there are at least HFA type relays two scram variables r

with different type logic relays-(either Agastat or Potter

& Brumfield).

i 2.

Each sensor relay Each sensor has two pairs i

has a single pair of contacts in the of contacts in applicable trip channel.

the applicable trip channel.

)

s D.

Scra'm Contactors l

1.

All scram contactors No difference i

are one type (CE Type CR105).

1 2.

Eight scram contactors No difference (two per RPS channel) perform the trip function.

E.

Air Pilot Solenoid valves 1.

Generic model has Two HCU valves with single dual solenoid operators solenoid operators. Trip-for each individual BCU ping of both valves is air pilot valve.

De--

required for individual energizing both sole-control rod scras.

noids results in a scram of the individual control rod.

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MDE 87-0485-1 NP Sectien III - Assessed Reliability Effect of RPS Configuration Differences Plant Specific Assessed Reliability BWR Generic Model Difference

-Effect F.

Backup Scram 1.

Actuation of backup Backup scram valves scram valves are con-actuations are controlled trolled by same output by scram contactors from scram contactors as both the manual and auto-RPS.

scram system.

2.

Trip logic for backup No difference scram valves is an i

energized to trip versus de-energized to trip for individual HCU air pilot valves.

3.

Backup scram valves Test requirements for the are tested during backup scram valves are shutdown at least not specified in the once per 18 months.

plant Technical Specifi-cations.

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MDE-87-0485-1-NP s

Section III - Assessed Reliability Effect of RPS Configuration Differences Ple:* Specific Assessed Reliability BWR Generic Model

. Difference Effect-G.

Technica1' Specifications and Surveillance Test Procedure

• 1..

Generic model uses See Section II.G BWR6 Standard Tech-of this Appendix nical Specifications for plant specific which requires:

differences.

Allowable out-of-service time:

I hr Test time: 2 hrs Test frequency:

IW for APRM IM for others Calibration frequency:

IM for trip units R for transmitters 2.

Generic model assumes See Section II.H two actuations per scram of this Appendix contactor pair in each for plant specific trip logic channel for differences. The the APRM channel funce-total number of ional test and four act-actuations of ustions for the MSIY each scram contactor Closure Channel function-per year is 304.

al tests, and one actuation for the other scram variables. This leads to 272 total actuations of each scram contactor per year.

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