- - -

IEEEStd 323-1974Revision ofIEEE Std 323-1971(ANSI N41.5.1671)

A.1'- G.k~ C"J f'O

IEEE Standard-for Qualifying Class IEEquipment for Nuclear Power Generating Stations

Fornotification

''ure

Standard,fill out theattachedcard Sponsor

Nuclear Power Engineering Committee of theILEE Power Engineering Society.

- -Copyright 1974 by

The Institute of Electrical and Electronics Engineers, Inc.

No part of this publication may be reproduced in any fcrm.in an electronic retrieival system or otherwise,

without the prior writtepn permission of the publisher.

I

IEEE Standard for Qualifying C1ass IEEquipment for Nuclear Power Generating Stations

1. Scope

This djcument describes the basic require-ments for qualifying Class IE equipment andinterfaces that are to be used in nuclear powergenerating stations. The requirements pre-sented include the principles, procedures, andmethods of qualification. These qualificationrequirements, when met, will confirm the ade-quacy of the equipment design under normal,abnormal, design basis event, post design basisevent, and containment test conditions for theperformance of Class lB functions.

2. Purpose

The purpose of this document is to provideguidance for demonstrating the qualification ofClass IE equipment including components orequipment of any interface whose failure couldadversely affect the performance of Class 1Esystems and electric equipment. Qualificationrequired in IEEE Std 279-1971 (ANSIN42.7-1972), Criteria for Protection Systemsfor Nuclear Power Generating Stations andIEEE Std 308-1974, Criteria for Class IEPower Systems for Nuclear Power GeneratingStations can be demonstrated by using theguidance provided in this document.

The qualification methods described shall beused for qualifying equipment and for updatingqualification following modifications. Otherqualification guides for specific electric equip-ment or test methods (for example, IEEE Std344-1971, Guide for Seismic Qualification ofClass I Electric Equipment for Nuclear PowerGenerating Stations) will present specific re-quirements and should be used to supplementthis document.

3. Definitions

These definitions establish the meanings of

words in the context of their use in this guide.

analysis. A process of mathematical or otherlogical reasoning that leads from statedpremises to the conclusion concerning specificcapabilities of equipment and its adequacy fora particular application.

auditable data. Technical information which isdocumented and organized in a readily under-standable and traceable manner that permits in-dependent auditing of the inferences or con-clusions based on the information.

Class IE. The safety classification of the elec-tric equipment and systems that are essential toemergency reactor shutdown, containment iso-lation, reactor core cooling, and containmentand reactor heat removal, or otherwise are es-sential in preventing significant release of radio-active material to the environment.

components. Items from which the system isassembled (for example, resistors, capacitors,wires, connectors, transistors, tubes, switches,springs, etc).

containment. That portion of the engineeredsafety features designed to act as the principalbarrier, after the reactor system pressureboundary, to prevent the release, even underconditions of a reactor accident, of unac-ceptable quantities of radioactive materialbeyond a controlled zone.

demonstration. A course of reasoning showingthat a certain result is a consequence of as-surned premises; an explanation or illustration,as in teaching by use of examples.

design basis events. Postulated events, specifiedby the safety analysis of the station, used inthe design to establish the acceptable per-formance requirements of the structures andsystems.

design life. The time during which satisfactoryperformance can be expected for a specific setof service conditions.

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* IEEE Std323-1974 QUALIFYING CLASS IE EQUIP1MENT FOR

equipment qualification. The generation andmaintenance of evidence to assure that theequipment will operate on demand, to meetthe system performance requirements.

installed life. The interval from installation toremoval, during which the equipment or com-ponent thereof may be subject to design serviceconditions and system demands.

NOTE: Equipment may have an installed life of 40years with certain components changed periodically;thus, the installed life of the components would be lessthan 40 fears.

interface. A junction or junctions between aClass IE equipment and another equipment ordevice. (Examples: connection boxes, splices,terminal boards, electrical connections, grom-mets, gaskets, cables, conduits, enclosures, etc.)

nuclear generating station. A plant whereinelectric energy Is produced from nuclear energy.by means of suitable apparatus. The stationmay consist of one or more units which may ormay not share some common auxiliaries.

operating experience. Accumulation of verifi-able service data for conditions equivalent tothose for which particular equipment is to bequalified.

qualified life. The period of time -for whichsatisfactory performance can be demonstratedfor a specific set of service conditions.

NOTE: The qualified life of a particular equipmentItem may be changed during its installed life wherejustified.

sample equipment. Production equipmenttested to obtain data that are valid overamrangeof ratings and for specific services.

service conditions. Environmental, power, andsignal conditions expected as a result of normaloperating requirements, expected extremes inoperating requirements, and postulated condi-tions appropriate for the design basis events ofthe station.

type tests. Tests made on one or more sampleequipments to verify adequacy of design andthe manufacturing processes.

4. Introduction

The manufacturers and users of Class IEequipment are required to provide assurance

that such equipment will meet or exceed itsperformance requirements throughout its in-stalled life. This is accomplished through a dis-ciplined program of quality assurance that in-cludes but is not limited to design, qualifica-tion, production quality control, installation,maintenance, and periodic testing. This docu-ment will treat only the qualification portionof the program.

It is the primary role of qualification to as-sure that for each type of Class 1E equipmentthe design and the manufacturing processes aresuch that there is a high degree of confidencethat future eauipment of the same type willpe~o> ~-r iqu'reoa.The other steps in thequality assurance prog'r-m require strict controlto <ez th:t subsequent equipment of thesame type matches that which was qualifiedand is suitably applied, installed, maintained,and periodically tested. Margins used duringtype testing provide additional 'assurance thatthe equipment will perform as required.

Qualification may be accomplished in severalways: type testing, operating experience, oranalysis. These may be used individually or inany combination depending upon the particu-lar situation. In the first, it is expected that theequipment will be subjected to the environ-ments and operating conditions for which itwas designed and iHs performance measured. Ina'test program, it is usually practical only tosimulate environments -and -operating condi-tions. The limitations in such simulations,' theabbreviation of exposures permitted by increas-ing the severity of the environment, and thevalidity of data extrapolations must be takeninto account in the design of the test. Thesepoints will be covered in greater detail in thisand other guides. A representative test profileis given in' Section 7.1

Operating experience is a method of limiteduse as a sole means of qualification but of greatuse for the supplementation of testing in that itmay provide an insight into the change in be-havior of materials and equipment with time

1Representative in-containment design basis eventconditions for the principal reactor types are includedIn the appendixes for guidance in environmental simu-lation. These conditions may not be applicable for allspecific applications and the user should confirm thesuitability of these date and modify them as appropri-ate for qualification for any given Nuclear Power Gen-erating Station.

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NUCLEAR POWER GENERATING STATIONSIEEE Std323-1 974

under actual service and maintenance condi-tions. Operating experience is typically ofparticular use in qualification of equipmentoutside of the containment.

Qualification by analysis must include justi-fication of methods, theories, and assumptionsused. In general, electric equipment is too com-plex to be qualified by analysis alone, althoughit may be effective in the extrapolation of testdata and determination of the effects of minordesign changes to equipment that was pre-viously tested.

With all qualification methods, the end re-sult must be the documentation that mustde,,nistrat, the equipment's adequacy to per-form its required function. The documentationmust be in a form that allows verification bycompetent personnel other than the qualifiersand should contain the performance require-ments, the qualification method, results, andthe justifications.

5. Principles of Qualification

The capability of all Class IE equipment, in-cluding interfaces, of a nuclear power gen-erating station for performing its required func-tion shall be demonstrated. It is preferred thatthe demonstration be done by type tests onactual equipment. Operating experience andanalysis may be used to supplement type tests.

Principles and procedures for demonstratingthe qualification of Class IE equipment in-clude:

(1) Assurance that the severity of the qualifi-cation methods equal or exceed the maximumanticipated service requirements and conditions

(2) Assurance that any extrapolation or in-ference be justified by allowances for knownpotential failure modes and the mechanismleading to them

(3) On-going qualification testing of installedequipment whose qualified life is less than thedesign life of the equipment

(4) Documentation files which provide thebasis for qualification

(5) Qualification test data as required for on-going qualification testing

(6) Qualification of any interfaces associatedwith Class lE equipment

Several demonstration methods are accept-able. Service conditions, size, and aging are fac-tors which determine the demonstration

method to be used to assure proper qua'ifica-tion. Each method (see below) requires justifi-cation to assure acceptability.

5.1 Type Testing. Type testing of actual equip-ment using simulated service conditions is thepreferred method. This method should be usedfor qualifying the greater portion of equip-ment. However, a type test alone satisfies quali-fication only if the equipment to be tested isaged, subjected to all environmental influences,and operated under post-event conditions toprovide assurance that all such equipment wvillbe able to perform their intended function forat least the required operating tirme. XW.7hen sizeor other practical requirements limit or pre-clude type tests, this part of the demonstrationmay be completed by methods described inSect-ions 5.2, 5.3, and 5.4.

5.2 Operating Experience. Electric equipmentthat has operated successfully can be con-sidered qualified for equal or less severe service.Operating experience can provide informationon limits of extrapolation, failure modes, andfailures rates. The validity of operating experi-ence as a means of qualification shall be deter-mined from the type and amount of docu-mentation supporting the service conditionsand equipment performance.

5.3 Qualification by Analysis. Qualification byanalysis shall require the construction of a validmathematical model of the electric equipmentto be qualified, in which the performance char-acteristics of the equipment are the dependentvariables and the environmental influences arethe independent variables. The validity of themathematical model shall be justified by testdata, operating experience, or physical laws ofnature. Qualification shall consist of a quantita-tive analysis of the mathematical model of theelectric equipment that shall logically provethat the performance characteristics of theequipment meet or exceed the equipment de-sign specifications when the equipment is sub-jected to the design basis event environment.

Qualified life shall be determined from thetime dependent effects of the environmentalinfluences by quantitatively demonstrating thatthe performance characteristics of the equip-ment meet or exceed the design specificationsof the equipment after a design basis event,preceded by a time period during which theequipment is subjected to its normal design en-vironment. The maximum time period of

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* . IEEE Std323-1974 QUALIFYING CLASS IE EQUIPMENT FOR

normal environment for which the quantitativeanalysis is valid shall be the maximum life forwhich the equipment can be qualified by analy-sis.

In general, mathematical models which cansimultaneously quantify 'all the performancecharacteristics of electric equipment as func-tions of time and environment are unavailable.Because of this, analysis is generally used in thequalification process to quantify electric equip-ment performance as a function of the magni-tude of~a single environmental factor, such asseismic excitation, with aging and all other in-dependent environment factors held constantor to quantify the performance of electricequipment as a function of the time history ofa single -environmental factor with all inde-pendent environmental influences held con-stant. This single variable analysis is then usedfor justification and augmentation of partialtype tests and for providing the necessarylogical link between the various factors of atest in which two or more environmental para-meters are simulated.

The data used to support the qualification ofequipment by analysis shall be pertinent to theapplication and in an auditable form. The datashall be presented as a step-by-step descriptionfor one complete set of computations, ;o por-sons reasonably skilled in this type of analysiscan follow both the reasoning and the com-putations.

6A Combined Qualification. Equipment maybe qualified by type test, previous operatingexperience, analysis, or any combination ofthese three methods. Partial type test may beaugmented by tests of components where size,applications, time, or other test limitations pre-cdude the use of a full type test.

Partial type tests with extrapolation oranalysis, operating 'experience with extra-polation or analysis- and type tests supple-mented with tests of components and analysisare examples of the use of combinedqualification.

6.5 On-Going Qualification. The qualificationmethods described thus far may yield a quali-fied life of equipment that is less than the anti-cipated installed life of the equipment. Whenthis occurs, an on-going qualification programmay be implemented. Two methods for achiev-ing this are:

(1) aging and testing of identical equipment

or components may continue during the quali-fied life period of the installed equipment

(2) additional equipment could be installedbeside the required equipment, removed beforethe end of the qualified life period, and be typetested to determine its additional qualified life

Either of these methods would be consideredon-going qualification. Other methods withproper justification may be found equivalent.

6. Qualification Procedures and Method

The qualification of Class IE equipmentsshall include the following.

6.1 Identification of the Cla. IE EquipmentBeing Qualified.

6.2 Equipment Performance Specifications.Electric equipment specifications shall definethe equipment's Class IE requirements andshall include as applicable:

(1) Performance characteristics under de-fined normal, abnormal, containment test, de-sign basis event,' and post design basis eventconditions

-(2) The range of voltage, frequency, load,electromagnetic interference, and other elec-trical characteristics

(3) The installation requirements includingmounting method and configuration(s) - -

(4) Preventive maintenance schedule for theinstalled life of the equipment, (including lubri-cants and seals)

(5) The design life of the equipment and thedesign life of any components which may havea life shorter than that of the complete equip-ment

(6) Control,- indicating, and other auxiliarydevices contained in the equipment or externalto the equipment and required for -proper op-eration

(7) The range, type, and duration of environ-mental conditions including temperature, pres-sure, humidity, radiation, chemicals, andseismic forces

(8)' Coimplete description and number ofoperating cycles including periodic testing

(9) Qualified life. (This Performance Speci-fication 'entry may be established during thequalification testing)

2 Throughout this document the use of the terrmCass IE equipment also indludes appropriate interfac.s.

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NUCLEAR POWER GENERATING STATIONSIEEE Std323-197* 4

6.3 Type Test Procedures6.3.1 General. The type test shall be de-

signed to demonstrate that the equipment per.formance meets or exceeds the requirements ofthe equipment specifications for the plant. Thetype. test shall consist of a planned sequence oftest conditions that meet or exceed the ex-pected or specified service conditions, includ-ing performance margin, and shall take accountof both norima and abnormal operation.

6.3.1.1 Test Plan. The first step in the testprocedure is the preparation of the test plan.The plan %hould be compatible with the equip-ment specification and should contain suf-ficient detail to describe the required tests andprovide an auditable link between the specifica-tions and the test results. Auditable link mea-;:that the plan should provide proof that the testmethod used was adequate, as this is not al-ways discernible from the test results.

The test plan should contain the followinginformation:

(1) Equipment descriptions(2) Number (quantity) of units to be tested(3) Mounting and connection requirements(4) Aging simulation procedure(5) The service conditions to be simulated(6) Performance and environmental variables

to be measured(7) Test equipment requirements including

accuracies(8) Environmental, operating, and measure-

ment sequence in step-by-step detail(9) Performance limits or failure definition(10) Documentation-(Section 8.3)(11) Statement of nonapplicable portions of

the specification(12) A description of any conditions pecu-

liar to the equipment which are not coveredabove, but which would probably affect saidequipment during testing

6.3.1.2 Mounting. Equipment shall bemounted in a manner and a position thatsimulates its expected installation when inactual use unless an analysis can be performedand justified to show that the equipment's per-formance would not be altered by other meanof mounting. By manner is meant the means tobe used such as bolts, rivets, welds, clamps, etc.By position is meant the spatial orientationwith respect to the gravitational field of theearth. The effect of any interposing structureswhich are required for installation, such as con-trol boards, stands, legs, pedestals, etc. shall be

taken into account in specifying the testmounting.

6.3.1.3 Connections. Equipment shall beconnected in a manner that simulates its ex-pected installation when in actual use unless ananalysis can be performed and justified to showthat the equipment's performance would notbe altered by. other means of connection. Bymanner is meant the means to be used in con-nection to equipment such as wiring, connec-tors, cables, conduit, terminal blocks, serviceloops, piping, tubing, etc.

6.3.1.4 Monitoring. The test shall bemonitored using equipment that provides reso-lution fk .' ' ._ "-.I"ingful changes in thevariables. The test equipment shall be cali-lo-.4.. .aainst audct' :-: calibration standardsand shall have documentation to support suchcalibration. The time interval between measure-ments shall be such as to obtain the time de-pendence of each variable. In describing testsequences, the measured variables may beclassified into general categories as follows:

6.3.1.4.1 Category I - Environment.Temperature, pressure, moisture content,3 gascomposition, vibration, and time.

6.3.1.4.2 Category II-Input ElectricalCharacteristics. Frequency, current, voltage,power to the equipment, and time duration ofthe input.

6.3.1.4.3 Category III - Fluid Char-acteristics. Concentration of chemical con-stituents in fluid injected into the test chamberplus the flow rate and spray disposition andtemperature of such fluids.

6.3.1.4.4 Category IV - RadiologicalFeatures. Nuclear radiation data including en-ergy type, energy level, exposure rate, and in-tegrated dose.

6.3.1.4.5 Category V -Electrical Char-acteristics. . Insulation resistance of electricalcomponents; voltage, current and power out-put; response time; frequency characteristicsand simulated load.

6.3.1.4.6 Category VT - MechanicalCharacteristics Thrust, torque, time, and loadprofile.

6.3.1.4.7 Category VII - AuxiliaryFunction Measurements. Function measure-ments related to Class EE equipments which

3 Appendix C contains a preferred method for as-suring saturated steam conditions in a test environment.

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IEEE Std32S-1974 QUALIFYING CLASS IE EQUIPMENT FOR

are included in the equipment but not neces-sary for its own operation; that is items whichare required to provide a signal to control otherClass IE equipment. Included under this head-ing would be auxiliary switches and positionfeedback potentiometers. -Measurements shallbe taken which confirm; the capability of theequipment tb handle rated or specified loadand to provide rated or specified accuracy.Relevant measurements would include: currentcarrying and current interrupting capability ofswitches; contact resistance of limit switcheswith co tacts closed; and potentiometer resist-ance and iniearity n

- 6.3.1.5 AlMarg.'N. Maigin is the differencebetween the most severe specified service con-ditions of the plant and the conditions used intype testing to account for normal variations incommercial production of equipment and rea-sonable errors in defining satisfactory per-formance. The qualification type testing shallinclude provisions to verify that adequate mar-gin exists. In defining the type test, increasinglevels of testing, number of test cycles, and testduration shall be considered as methods of as-suring adequate margin does exist.

Suggested factors to be applied to serviceconditions for type testing are as follows:

(1) Temperature: + 150F (S°C). When quali-fication testing is conducted under saturatedsteam conditions, the temperature margin shallbe such that test pressure will not exceed satu-rated steam pressure corresponding to peak ser-vice temperature by more than 10 lb, in2

(2) Pressure: + 10 percent of gauge, but notmore than 10 lbg/in2 [7.03(10- ) kg/cm2 .

(3) Radiation: + 10 percent (on accidentdose)

(4) Voltage: I 10 percent of rated value un-less otherwise specified

(5) Frequency: * 5 percent of rated valueunless otherwise specified1 (6) Time: + 10 percent of the period of time

the equipment is required to be operational fol-lowing the design-basis event- (7) Environmental Transients: The initialtransient and the dwell at peak temperatureshall be applied at least twice

(8) Vibration: + 10 percent added to theacceleration of the response spectrum at themounting point of the equipment

NOTE: Negative factors shall be applied when loweringthe value of the service conditions increases theseverity of the test.

. 6.3.2 Test Sequence. The type tests shall berun on the equipment in a specified order. Formost equipment and applications, the follow-ing constitutes the most severe sequence; how-ever, the sequence used shall be justified as themost severe for the item being tested.

(1) Inspection may be performed to assurethat a test unit has not been damaged due tohandling since manufacture and to determinebasic dimensions. This inspection shall not bedirected to select a specific unit for type test-ing :

(2) The equipment shall be operated undernormal conditions to provide a data base forcomparison with performance under morehighly stressed conditions. Certain measure-ments such as drift (rate of change with time)of a parameter may be made at this time

(3) The equipment shall be operated to theextremes of all performance and electrical char-acteristics given in the equipment specificationsexcluding design basis event and post designbasis event conditions unless these data areavailable from other tests on identical or es-sentially similar equipment

(4) Equipment shall be aged in accordancewith Section. 6.3.3 to put it in a conditionwhich simulates its expected end-of-qualified-life condition including the effect ofradiation (design basis event radiation may beincluded). If the required radiation level can beshown to produce less effect than that whichwould cause loss of the equipment's Class IEfunction, radiation need not be included aspart of aging. Certain key measurements shouldbe made following aging to determine if theequipment is performing satisfactorily prior tosubsequent testing

(5) The aged equipment shall be subjected tosuch mechanical vibration as will be seen inservice. This should -include simulated seismicvibration (see IEEE -Std- 344-1971), self-induced vibration (see IEEE Std 334-1971,Trial-Use Guide for Type Test of Class I Elec-tric Valve Operators for Nuclear Power Gen-erating Stations), or vibration from othercauses (such as might be seen by pipe-mountedequipment) . . - .

(6) The aged equipment shall next beoperated while exposed to the simulated designbasis event (Section 7) [radiation may be ex-cluded if incorporated in (4) above]. Thosefinctions which must be performed during thesimulated design basis event shall be monitored

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IEEE StdNUCLEAR POWER GENERATlNG STATIONS 323.1974

(7) The equipment shall then be operatedwhile exposed to the simulated post accidentconditions (following exposure to accidentconditions). Those functions which must beperformed following the simulated design basisevent shall be monitored during this simulation

(8) Disassemble, to the extent necessary forthe inspection of the status and condition ofthe equipment and record the findings

6.3.3 Aging. The objective of aging is to putsamples in a condition equivalent to the end-of-life condition. If previous aging of various de-vices exists, it. can be utilized provided thesedata are applicable and justifiable in regard tothe service conditions that are required by theperformance specifications of the device to betype tested.

A short period of accelerated thermal agingmerely simulates service life; however, it pro-duces some deterioration and, when followedby vibration may produce realistic failuremodes.4 Radiation shall be added to otherknown degrading influences where appropriate.Margins over that expected in the qualified lifeshall be provided in the application of each in-fluence. Electromechanical equipment (motors,relays, etc) shall be operated to simulate theexpected mechanical wear and electrical con-tact degradation (for example, contact pitting)of the device to be type tested.

An accelerated rate for the number of cyclesequal to the required number during the designlife may be utilized provided the rate shall notbe accelerated to any value which results ineffects that would not be precant at normalrates.

For insulating materials, a regression line(see IEEE Std 101-1972, Guide for StatisticalAnalysis of Thermal Life Test Data) may beused as a basis for selecting the aging time andtemperature. Sample aging times of less than100 hours shall not be permitted.

6.3.4 Radiation. All materials or com-ponents which may be degraded to a degreewhich would adversely affect performance ofClass IE functions by the radiation exposureexpected to occur during normal service andpostulated accidents shall be irradiated tosimulate this exposure. Radiation shall be ap-

4See IEEE Std 1-1969, General Principles forTemperature Limits in the Rating of Electric Equip-ment.

plied as a part of the sequence of environmentsrepresentative of service conditions. The equip-ment shall be subjected to the significant typeof radiation equivalent to that expected in ser-vice. However, if more than one type of radia-tion is significant, each type can be appliedseparately. In determining the total requiredtest radiation equivalent to that of service life,consideration shall be given to oxidation gas-diffusion effects. To facilitate the use of a rea-sonable test time, an accelerated exposure ratemay be necessary. Thus, to allow margin forthese effects, a greater total dose than the ser-vice lifetime dose should be applied. FormulLsfor approximating the test dose equivalent toservice are given in IEEE Std 278-1967 (ANSIN4.1-1967), Guide for Classifying Electrical In-sulating Materials Exposed to Neutron and

-Gamma Radiation and ASTM D 2953-71, Clas-sification System for Polymeric Materials forService in Ionizing Radiation.

6.3.5 Vibration. The aged equipment shallbe qualified for expected seismic events in ac-cordance with IEEE Std 344-1971. In addition,equipment subject to nonseismic vibration dur-ing norma] and abnormal use shall be subjectedto such typical vibration following the agingand seismic procedures. Vibration to besimulated shall include self-induced vibration(such as the starting and running of a motor,vibration from nearby equipment, or vibrationfrom equipment) which produces the mountingsupport for the Class IE equipment beingqualified (such as pipes, generators, motors,etc).

6.3.6 Operation UnderNormal and AccidentConditions. Means shall be provided during thetype test for electrically energizing the equip-ment, applying simulated loads, applying inputsignals, and exposing it to simulated environ-mental conditions (for example, temperature,pressure, moisture, vibration, nuclear radia-tions, chemical solutions, jet forces, and chem-ical composition of the ambient environment).

6.3.7 Inspection. Upon completion of typetesting, the equipment shall be dismantled topermit all parts to be appropriately tested andvisually inspected. The condition of electricalinsulation, mechanical parts, bearings, lubri-cants, electrical contacts, wiring, gear drivetrains, linkages, and other related componentsshall be recorded.

6.4 Operating Experience6.4.1 General. Qualification of electric

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*- IEEE Std* 323-1974' QUALIFYING CLASS IE EQUIPMENT FOR

equipment by operating experience shall con-sist of determining the past history of per-formance and service conditions of the equip-ment type to be qualified, correlating operatingservice conditions with design servibe condi-tions, and proving that the Class IE per-formance characteristics of the equipment willmeet or exceed the equipment specificationunder design service conditions.

6.4.2 Operating History.6.4.2.1 The operating environment of the

electric equipment to be qualified shall bedetermined and shall be justified by analysis ofthe effeits of noncontinuous measurements.The documentation of the operating environ-me-,;' shall include physical locations andmounting arrangements of the equipments inthe operating facilities.

6.4.2.2 The performance of the electricequipment type to be qualified shall be deter-mined from measured data or analysis offailures that may have occurred or both. Docu-mentation of all Class IE performance shall in-clude measurement or-determination of all per-formance characteristics in the equipmentspecifications, recording and analysis of allfailures and trends that occurred during theoperating period, and a log of all periodic main-tenance (including adjustments and calibra-tions) and inspections.

6.43 Determination of Qualification. It shallbe documented that the equipment whoseoperational history becomes a basis for qualifi-cation is typical of equipment bearing the samedesignation.

The electric equipment type shall be con-sidered to be qualified by demonstrating thatthe recorded operating environment equals orexceeds the design environment in severity, andthat the performance of 'the in service equip-ment equaled or exceeded the specified userrequirements. The period of time for which theabove requirements can -be shown to be metwith reasonable margin shall be the qualifiedlife.

It should be noted that if the design environ-ment includes seismic accelerations followedby a design basis event environment that ismore severe than the recorded in service en-vironment, then the installed equipment must,in general, be removed from service and sub-jected to a partial type test to include the-seismic and design basis event effects beforethe equipment can be considered fully qualified.

6.5 Analysis6.5.1 Gencral. Qualification by analysis shall

consist of a-mathematical or logical proof thatthe Class IE performance of the equipment tobe qualified meets or exceeds its specified per-formance when subjected to its specifiednormal and design basis event environments. Ingeneral. -this proof must be based on estab-lished principles, operating experience data,partial type test data, or combinations of these.All assumptions, including extrapolations thatare made in proof, shall be justified by estab-lishing principles or verifiable test data; and theanalysis shall be of a form that can be readilyunderstood and verified by people qualified inthe pertinent discipline of engineering orscience.

6.5.2 Mathematical Afodeling The first stepin the qualification by analysis is generally theconstruction of a valid mathematical model ofthe electric equipment to be qualified. Themathematical model shall be based upon estab-lished principles, verifiable test data, or operat-ing experience data. The mathematical modelshall be such that the performance of the elec-tric equipment is a function of time and thepertinent environmental parameters. All en-vironmental parameters listed in the equipmentspecification must be accounted for in the con-/struction of the mathematical model unless itcan be shown that the effects of the parameterof interest are dependent on the effects of theremaining environmental parameters.

6.5.7b9xfrapoldt]oi Extrapolation is ananalyticat S qhnih ch may be used to aug-ment testing. However, in order to be con-sidered valid for qtialifying Class EE equipmentcertain guidelines must be met.

6.5.3.1 Failure Modes. The modes offailure produced under intensified or ac-celerated -environmental or other influencesshall be the same as those predicted under therequired service conditions. If not, the in-tensity of the accelerating variable shall be re-duced until failure modes and mechanisms pro-duced are consistent with those known or pre-dicted for required service conditions.

6.5.3.2 Characterization of Effects. Thelife (or other attribute) being extrapolated shallbe characterized as a function of the environ-mental 'variable to provide a basis to forecastchanges of the equipment performance withtime (or other domain).

6.5.3.3 Extrapolation Basis. To establish

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I

I

NUCLEAR POVER GENERATINGw; STATIONS1EEE Std323-i1¶V74

the basis for extrapolation. equipment or com-ponents shall be subjected to a comparable en-vironment for a time or level necessary tojustify the extrapolation of the test results tothe total time or level to be qualified.

6.5.4 Determination of Qualification. Theelectric equipment type shall be considered tobe qualified by demonstrating that the equip-ment performance will meet or exceed itsspecified values for the most severe environ-ment or sequence of environments in theequipment specification during its qualifiedlife. The Severity of the environmental para-meters shall be based upon knowledge of thefailure mode. and failure mechanisms of theequipment which may be determined by test.The qualified life shall be based upon theknown limits of extrapolation of the time de-pendent environmental effects if an acceleratedaging test was used to determine the mathe-matical model.

6.6 On-Going Qualification. Some equipmentmay have a qualified life less than the requireddesign life of a nuclear power generating sta-tion. There are two recommended methods oflong term qualification (see Section 5.5):

(1) Equipment of the same type as thatwhich has been type tested and installed in a

_-,\station shall be'placed in an environment thataccelerates thie-aging under controlled condi-

r-^ t tions. When it is determined that the equip--ment has reached the required design life of thestation, it shall be removed from the ac-celerated life environment and type tested. Theinstalled equipment may be considered ade-

j <; quate for the design life of the station if the_. o, equipment that was subjected to the ac-

celerated life environment passes the type test(2) Additional identical equipment shall be

installed in a nuclear generating station in loca-tions where service conditions equal or exceedthose of the equipment to be qualified. Thisequipment shall be removed after a plannedperiod less than the previously qualified lifeand subjected to a qualification test similar tothat performed prior to its installation. Thistest must include additional accelerated aging.Successful completion of this type test extendsthe qualified life of the installed equipment.This procedure shall be repeated until thequalified life equals the required installed lifeof the equipment

Should the above methods demonstrate thatthe qualified life is less than the required life, a

periodic replacement plan shall be instituted.

6.7 Criteria of Failure. In the evaluation of thequalification test results, any sample equip-ment is considered to have failed when theequipment does not perform the Class IE func-tions required by the equipment specifications.

6.8 Modifications. Modifications should not bemade to the equipment, or to the equipment ortest specifications, after the start of the typetest or beginning of the operating experiencereporting period since such modification willnormally render the test and experience resultsinconclusive. Modifications may be made onlyif full justification it documented on tilhe bfs vthat such modifications have no bearing on thevalidity of the test., Each modification to the equipment or tothe equipment specification made after thetype test or beginning of the operating ex-perience reporting period shall be evaluated todetermine its effect on the equipment qualifi-cation. This evaluation shall indicate whetheror not complete requalification is required. Ifnot, the analysis or data and evaluation thatdemonstrates the effect of the modification onequipment performance shall be added to theoriginal qualification documentation.

Components of the equipment which can beshown to be unaffected by the change need notbe type tested again, as previous operating ex-perience and type test data along with com-plete qualifications for portions affected by themodification shall constitute qualification ofthe entire equipment.

Any changes in qualification basis, materialsof construction, lubricant, mechanical stresses,clearances, manufacturing process, dielectricstress levels, etc, shall be identified and theequipment requalified if necessary. Necessityshall be based on effect of the change on theequipment's Class TE functions.

6.9 Documentation. Files which provide docu-mentation of the qualification procedures,methods, and results shall be maintained toprovide a current basis for qualification andpermit comparisons if future tests are con-ducted.

7. Simulated Service Condition Test Profile

The user shall furnish sufficient environ-mental data to allow the simulation of the

15

IEEE Std323-1974. . - - QUALIFYING CLASS IE EQUIPMENT FOR

postulated design basis event -profile. To -thisshall be added performance margins (see Sec-tion 6.3.1.6) to derive the appropriatesimulated service condition test profile (Fig 1).

8. Documentation

8.1 General. The qualification documentationshall verfiY that each type of electric equip-ment is qualified for its application and meetsits specified performaance requirements. Thebasis of qualification shall be explained, toshow the relationship of all facets of proofneeded to support adequacy of the completeequipment. Data used to demonstrate thequalification of the equipment shall be per-tinent to the application and organized in anauditable form.

8.2 Documentation Files. The user shall main-tain a qualification file (not necessarily at theplant site). The file shall contain the informa-tion as listed in Sections 8.3, 8.4, 8.5, and 8.6depending upon the qualification method used.

8.3 Type Test Data. The type test data shallcontain:

(1) The equipment performance specifica-tions (Section 6.2)

(2) Identification of the specific feature(s)to be demonstrated by the test

(3) Test plan (Section 6.3.1.1)(4) Report. of test results

The report shall include:(a) Objective(b) Equipment tested.(c) Description of test facility (test setup)

and instrumentation used including calibrationrecords reference

(d) Test procedures(e) Test data and accuracy (results)(f) Summary, conclusions, and recom-

mendations(g) Supporting data(h) Approval signature and date

8.4 Operating Experience Data. The operatingexperience data shall contain:

(1) The equipment performance specifica-tions (Section 6.2)

(2) The interface or boundary conditions ofthe equipment

Fig 1Simulated Service Condition Test Profile

'TSOI

ftTSO2 TSN

I92P2 -

6 IPo)

OF SPECIFIED SEKVICE CONDAS DEFINED BY USER (UPON I

SHOULD BE BASED)

EXA4PLE OF TEST PROFIIZSERVICE CONDITIONS

S. a

Z II 3.

a. -!

PERIOD Of SPRAY (IF REQUIRED)

t TYPICAL OPERATING AND/DRMEASUREMESNT POINHS

a3 P3

I TIION -@4 PWHICH

.E COVERING

_95 amPS

aoN W

ON b

90

ITI T21T31

0 1

ADDITIONAL PEAt RAN-SIENT TO ASSUREPERFORMACE MARCIN

ITI'2T2,2T'32

I1,-

TX T15 ITX 2TK EXTENDED PERIOD TO ASSURE

-| RFORMANCE MARGINTIME -I SPECIFIED PERIOD OF OPERATING

CAPABILITY TO FUNCTION DURING AFOLLOWING A DESIGN BASIS EVENT

AD

16

NUCLEAR POWER GENERATING STATIONSIEEF Std323-1 9 { -

(3) The specifications of equipment forwhich operating experience is available

(4) Identification of the specific features tobe demonstrated by operating experience

(5) Comparison of past application andspecifications with the new equipment specifi-cations for each feature identified above

(6) Summary and source of operating ex-perience applicable to equipment qualification

(7) The basis on which the data have beendetermined to be suitable and the equipmentqualified

(8) Approval signature and date

8.5 Analysis. The analysis data shall contain:(1) The equipment perfonnance specifica-

tions (Section 6.2)

(2) The interface or boundary conditions ofthe equipment

(3) The specific features, postulated failuremodes, or the failure effects to be analyzed

(4) The assumptions, empirically derivedvalues, and mathematical models used togetherwith appropriate justification for their use

(5) Description of analytical methods orcomputer programs used

(6) A summary of analytically establishedperformance characteristics and their accept-ability

(7) Approval signature and date

8.6 Extrapolation. Where the test data oroperating experience data have been extra-polated, the basis for the extrapolation sh.] beincluded.

17

IEEE Std323-1974 QUALIFYING CLASS IE EQUENMENT FCMA

Appendix A

In-Containment Design Badis Event Environment Simulation For PressurizedWater Reactors and Boiling Water Reactors

(These appendixes are not part of IEEE Std 323-1974, Qualifying Cass IE Equipment for Nuclear Power GeneratingStations.)

NOTE: All the conditions presented are representativeand may need modification to assure their suitabilityto any specific equipment application.

Al General. The design basis event environ-ment conditions to be simulated for a Pres--surized Water Reactor (PWV'R) or Boiling WaterReactor (BWR) resulting from a postulatedloss-of-coolant accident (LOCA) which are tobe simulated generally consist of exposure tohot gases or vapors (for example, steam) and aspray or jet of water, chemical solution, or

other fluids. These environmental conditionsdiffer markedly among different types of re-actors, and also vary significantly from locationto location in the plant. In most locations out-side of the primary containment there will beno special environmental conditions resultingfrom a design basis event. There are other loca-tions, such as within the reactor building insome BV"R plants, where there will be specialenvironmental conditions, but these may beless severe than those within the primary con-

Fig AlTest Chamber Temperature Profile for Environment Simulation (Combined PWR/BWR)

ADDITIONALPEAK TRANSIENT DURING AND FOLLOWINGTRANSIENT A DESIGN BASIS EVENT

340

320

300

280

'-

= 250'Ii

W

200

140

5min 5 h l0ST It HE

18

* IEEE StdNUCLEAR POWER GENERATING STATIONS 323-1974

Table AlTest Conditions for Pressurized Water Reactors*

(Typical In-Containment Design Basis Event Test Conditions)

(1) Exposure to Nuclear Radiationt4 megarads after 1 hour

20 megarads after 12 hours24 niegarads after 1 day40 megarads after 10 days55 megarads after I month

110 megarads after 6 months150 megarads after 1 year

(2) Exposure to Steam and Cnemicals

(a) Steam Exposure Temperature PressureTime (0F) V C) (lbflin2" gauge) (MPa)

0 to 10 seconds 120 to 300 48.9 to 148.9 0 to 70 0 to 482.610 seconds to I0 hours 300 148.9 70 482.610 hours to 4 days 210 98.9 40 275.84 days to 1 year 167 75.0 5 34.5

(b) Spray Exposure. Continuously spray vertically downward for first 24 hours with a solution of thefollowing composition at a rate of 0.15 (gal/min)Ift2 (6.1 (mllmin)1m 2 ) of area of the test chamberprojected on to a horizontal plane.

0.28 molar H3 BO3 (3000 parts per million boron)0.064 molar Na2 S2 03NaOH to make a pH of 10.5 at 77°F (about 0.59 percent)Dissolve chemicals, on a one-liter basis, in the following order:(I) 600 ml potable water(ii) H3 BO3(iii) NaOMM(iv) Na2 S2 03(v) Add remainder of water to volume of one liter(vi) Add NaUH to make a pH of 10.5 at 77F, as required for the initial spray solution.

*The values given in this table may vary from plant to plant and may or may not contain adequate margin.tConservative calculation of radiation dose to containment atmosphere resulting from beta and gamma radiationemitters released from the primary system and at a location within the primary containment.

Table A2Test Conditions for Boiling Water Reactors*

(Typical In-Containment Design Basis Event Test Conditions)

(1) Exposure to Nuclear Radiationst26 megarads integrated over the accident

(2) Exposure to Steam and Spray

(a) Steam Exposure Temperature PressureTime (IF) (6C) (lbf in 2 , gauge) (kPa)

0 to 20 seconds 135 to 280 57.2 to 137.8 0 to 62 0 to 427.520 seconds to 5 min 280 to 340 137.8 to 171.1 62 427.55 min to 3 hours 340 171.1 40 275.83 hours to 6 hours 320 160.0 40 275.86 hours to 4 days 250 121.1 25 172.44 to 100 days 200 93.3 10 68.9If it is not practical to reproduce the specified pressure and temperature profiles combined, it isacceptable during the first four days to follow the temperature profile and allow the pressure toconform to saturated conditions (100 percent relative humidity). This procedure is justified by thefact that temperature is the more important parameter and increasing the pressure (to maintainsaturated conditions) will increase the severity of the test. if anything.

(b) Spray Exposure. Continuously spra vertically downward with demineralized water at a rate of0.15 (gallmin)/ft2 (6.1 (mllmin)/ml) of area of the test chamber projected onto a horizontal plane.

*See 1st footnote to Table Al.

tSee 2nd footnote to Table Al.

19

I .

IEEE Std323-1974 QUALIFYING CLASS IE EQUIPMENT FOR

tainment. The equipment specification shall de-fine the actual environment in detail.

The test profile to simulate the environ-mental conditions anticipated within theprimary containment in current plants withPressurized Water Reactor (PWVR) and BoilingWater Reactor (BWR) are shown in Tables Aland A2. If it is desired to qualify equipmentfor in-containment service for both PWRs andBWRs, the test conditions may be chosen toencompass both test profiles, 'including thechemica4 spray specified for PWl;Rs and thetemperature/pressure profile specified forBWRs. Fig Al shows a representative testchamber profile for al combined PWR/BWRtest. If the actual conditions are different fromthese curves, the parameters may be adjustedaccordingly. As noted above for out-of-containment service, the conditions may beless severe and generally are not different fromthe normal operating conditions. - -

Although the equipment is expected to ex-perience at most only one severe environmentaltransient as a result of a LOCA event during itsinstalled life, it is recommended that it be ex-posed to two initial steam/chemical transientsin the Accident Environment Simulation, as

shown in the profiles (Fig Al).

A2 Simulation Sequence. Suggested sequencesinclude:

(1) Expose sample equipment to simulated(a) Aging(b) Radiation (if size permits and if war-

ranted by radiation tolerance limits and effectson Class YE performance)

(c) Vibration(2) Stabilize operation in normal environ-

ment to establish reference conditions(3) Inject steam and chemical sprays at rates

simulating service conditions, raising thetemperature and pressure to test profile-levelsrequired

(4) Maintain these conditions for threehours. De-energize for static readings includinginsulation resistance to ground. Re-energizeone additional hour

(5) Reduce the environmental conditions tothe normal operating conditions within twohours

(6) Repeat first cycle; but at the end ofthree hours, lower pressure in steps as requiredto simulate post-event profile for which equip-ment is to be qualified

Appendix B

In-Containment Design Basis Event Environment Simulation ForA High Temperature Gas Cooled Reactor (H.TGR)

NOTE: All the conditions presented are representativeand may need modification to assure their suitabilityto any specific equipment application.

The design basis event (DBE) environmentsto be simulated for a high temperature gascooled reactor (HTGR) typically consist of ex-posure to helium or steam. Table B1 in con-junction with Figs Bi and B2 present the anti-cipated pressure and temperature history of thecontainment atmosphere for design basis eventenvironments; hot helium blowdown and hotreheat steam line rupture. Shown with thehelium and steam exposure profiles is a repre-sentative equipment surface temperature pro-file. It is the responsibility of the equipmentmanufacturer to determine which of the con-ditions will present the most severe environ-ment for his equipment and to specify the

criteria he used in selecting this condition. Ifdoubt exists in identifying which condition isthe most severe, consideration should be givento testing the equipment under both condi-tions.

Various test profiles may be used to producethe same'equipment conditions provided this isadequately demonstrated by analysis or othermeans. The helium blowdown DBE profile as-mumes helium is used, however, nitrogen, air, or

other gas can be used provided the exposureprofile is appropriately modified.

The qualification testing shall assure ade-quate margin of survival. Although the equip-ment is expected to experience at most onlyone severe environmental transient as the resultof a DBE during its installed life, it is suggestedthat it be exposed to at least two DBE

20

I IEEE Std323-1974NUCLEAR POWER GENERATING STATIONS

goo

700

500

I.

ia-

so0

400

50 CC'A

30

3t;300

200

1oo I0I I I c5 I I -X - C5 I

w , e -, aa a gaLA A

w e e Aw

IC

Fig B1Typical Temperature and Pressure History for Environment Simulation of HTGR

Containment Atmosphere Response Following a Hot Helium Blowdowninto Containment (To - 1000F, P. = 14.7 lbifin2 . Note: For Long-TermTesting, Assume Equilibrium Conditions at T = 120'F and 35 lbf/in2 .)

Table B1Test Conditions for High-Temperature

Gas-Cooled Reactors(Typical In-Containment Design Basis Accident Conditions)

(1) Exposure to Nuclear Radiation2 megarads after I hour

12 megarads after I day75 megarads after I year

(2) Exposure to Steam and Gases(a) Hot helium exposure - see

Fig Be(b) Superheated steam exposure -

see Fig B2

21

IEEE Std323-1974 QUALIFYING CLASS IE EQUIPMENT FOR

transients as a metnod of demonstrating thisimargin. This method is shown in Figs Bi and

- B2.

As an aid in preparing for an environmeutalsimulation, the typical normal operating condi-tions for an HTGR are presented in Table B2.

l

Fig B2Typical Temperature and Pressure History for Environment Simulation of HTGRContainment Atmosphere Response Following a Steam Line Rupture Inside the

Containment (To = 1000 F, P0 - 14:7 lb /in2. Note: For Long-TermTestings Assume Equilibrium Conditions at T = 120 'F and P = 16 lbj/in2 .)

5oo

0oo

I

300

so

.0

30 L~

In

L.

20

I G

200

00lmc . i cc. I"- C iC r ~c ia * i- : W *j *j .- 40 c

- - .c' 2 - 4n In I£ I C I

. W of Cw~~~~q

22

I

NUCLEAR POVWER GENERATJNG STATIONSIEEE Std323-1974

Table B2HTGR Containment Building

(Normal Opera'ing Conditions)

Top Head Area Bottom Support Area

Average Ambient Maximum Average Ambient Maximum

Temperature 70-100'F 130°F 70-130'F 1600 F(21.1-37.8 C) (54.4-C) (21.1-54.4 C) (71.10 C)

Pressure -0.5 to 0.5 lb/lin2 , -0.5 to 0.5 lbj/in2, -0.5 to 0.5 lbj/in2 , -0.5 to 0.5 lb, /in 2,gauge gauge gauge gauge

(-3.4 to 3.4 kPa) (-3.4 to 3.4 kPa) (-3.4 to 3.4 kPa) (-3.4 to 3.4 kPa)Relative 10-80 percent 80 percent 10-80 percent 80 percent

RamdiatioRadiation e 2.5 to 25 mrd/hour < 100 mrd/hour 2.5 to 25 mrdlhour < 100 mrd/hour

Radiationdose for 8.8 X 103 rd 8.8 x Io- rd

plant life

Appendix C

Test Chamber Moisture Content

The simulation of Design Basis Event (DBE)conditions in qualification tests sometimes re-quires that a moisture-saturated environmentbe maintained at temperatures exceeding thehighest temperatures at which commerciallyavailable relative humidity and dewpointsensors are capable of functioning. This ap-pendix suggests one way in which the existenceof a saturated atmosphere can be assured insuch cases.

Generally, the chamber that contains theequipment under test is initially full of air, andsteam is injected into the chamber to executethe specified temperature profile. The analysisof moisture concentration inside the testchamber would be quite straight-forward if theair initially in the chamber were to remaintrapped inside it, or if the air were driven outcompletely by the introduction of steam. Butthe situation is generally intermediate betweenthese extremes, and there is no convenient wayof determining the exact state. This is il-lustrated by the following.

Consider a mixture of air and steam attemperature T and pressure P. The pressure ofthe mixture is equal to the sum of the partialpressures of steam (Pawn) and air (Pa. h:

PPst.am +P.,"

and at equilibrium, we have

T = Tsteam = Tair

For 100 percent relative humidity (RH), orsaturated conditions, it is necessary that thepartial steam pressure be equal to the pressureof saturated steam (P,.) at the temperature T.If one knew the partial pressure of steam in themixture, steam tables could be used to verifywhether Pstem and T correspond to saturatedsteam conditions and, therefore, whether theRH of the mixture is 100 percent. However,the difficulty of measuring the partial pressureof steam makes this impractical. One way toavoid this problem is to introduce moisture in-to the test chamber in a way that assuressaturation of the environment, as is describedbelow.

The gas in a test chamber will be saturatedwith water vapor, that is, have a relativehumidity of 100 percent, if thermal equili-brium exists between the water vapor andliquid water inside the chamber. Therefore, oneway to guarantee saturated conditions is toplace a container of water inside the chamberand keep its temperature at a value equal to thetemperature of the gas in the chamber. It isalso required that water vapor be evaporatedfrom the heated water at a rate capable ofsaturating the chamber volume in a tine that isshort by comparison with the duration of con-

23

stant-temperature dwells in the test profile. Tofacilitate this, the water should be heated toboiling prior to the start of the test. A furtherrequirement is that the chamber atmosphere bestirred at a rate adequate to maintain uniformconditions.

As an example, this can be done by spargingsteam through water in a vessel that is insidethe test chamber. The temperature of the watermust equal or exceed the temperature of thesteam/air mixture in the test chamber. Thesteam flow rate must be adjusted to meet thisrequirement as well as to satisfy the require-ments of the preceding paragraph, and a fan or

other means of mixing must be provided toassure uniformity of the chamber atmosphere.

The method described above will provide asaturated atmosphere essentially throughoutthe test. The only exception is the short periodrequired to reestablish equilibrium following atemperature rise. Since the amount of watervapor needed to saturate an environment de-creases with a drop in temperature, thereshould be no lag in maintaining saturated con-ditions following temperature drops. Othermethods of maintaining saturated conditionsmay be used provided their adequacy is demon-strated.

24