MIL-HDBK-705C29Flay1987SUPERSEDINGMIL-HDBK-705B26June1972MILITARYHANDBOOKGENERATORSETS,ELECTRICAL,MSASUH)WSNTANDINSTRUIIENTATIONMSTHODSFSC6115AMSCN/ADISTRIBUTIONSTATEMENTA. Approvedforpublicrelease;distributionisunlimitedDownloaded from http://www.everyspec.com-:.., ~..;.,,,..;.. . ... ... .DEPARTMENTOFDEFENSEWASHINGTON, D .C.20301MIL-HDBK-705CGeneratorSets,Electrical,MeasurementandInstrumentationMethods1. ThisMilitaryHandbookwaad&veloDedbv theUSArmyTrOOD SuuportCommand-BelvoirRe~earchDevelopmentandEng~aeeringCen~erinacc~~dance withMIL-STD-962andisapprovedfortheuseofallDepartmentsU.S.Government.2. Thispublication,revisionC,was.approvedon29printingandinclusioninthemilitaryhandbookseries.andAgenciesof theHay 1987,for3. Thiedocumentprovidesbasicandfundamental information onmeasurementandinstrumentationmethodsforevaluationofelectricalpowergenerators,generatorsetsandrelateditemewhen theseitemsaretestedinaccordance withMIL-sTD-705andsimilartestmethods.4. Beneficialcomments(recommendations, additions,deletions)andanypertinentdatawhichmaybeofuse in improvingthisdocumentshouldbeaddressedto: USArmyTroopSupportCommand- BelvoirResearchDevelopmentandEngineering Center,ATTN: STRBE-DS,FortBelvoir,VA 22060-5606, byusingtheself-addressed Standardization DocumentImprovement Proposal(DDForm1426)aPPearlngat theendof thisdocument,orby letter.iiDownloaded from http://www.everyspec.comMIL-HDBK-705CFOREWORD1. Thishandbook is intendedtoexplainandestablishconventionsforterminology,instrumentation, methodsofmeasurementandacceptedproceduresassociatedwith thetestingandevaluationofelectricgenerators,generatorsets,andrelateditems. Itistobe usedinconjunction withMIL-STD-705todeterminecapabilities,conditionsandcompliancewith therequirementsofprocurementdocuments. Themethodshereincontainpreparatoryproceduresandbasicdetailedrequirementsforgeneraluse instruments, measurementsandinstrumentation,whilethemany specificmethodsof testareestablishedinMIL-sTD-705,GeneratorSets,Engine-Driven,TestMethods andInstructions.2. Sometestinstrumentsillustrated hereinareno longerbeingmanufacturedandtheirfunctionshave beensupersededby newertypesof instruments;theoldertypes,however,arestillbeing usedinsomeareasandarestillacceptable;therefore,theirinclusioninthishandbookwillbecontinueduntilsuchtimeastheirremovalwillbe in theGovernmentsbestinterest.3. BecausethishandbookiscloselyalliedtoMIL-STD-705,referencesfromonetotheotherarefreelyusedparticularlyfromMIL-STD-705tothisdocument.Inspectorsandtesterswill findneed forboththehandbookandstandardwhenworkingwith electricalpowergenerationequipment.4. Dueto thecomplexityof specifiedrequirementsinprocurement documentscoveringengine-drivenelectricgeneratorsandothersimilartypeaofelectricmachinery,militarypersonnelwill findthishandbookespeciallyhelpfulasaconvenientsourceofgeneralinformationonelectricalinstruments andtheirproperuse. Thie technologyhasbeendocumentedfromexperiencebygovernmentandindustryengineersand technicianswiththemanufacturing,procurementandtestingofelectricalpowergenerationequipment.. ..111Downloaded from http://www.everyspec.comMIL-HDBK-705CPAM .1.1.11.21.2.11.2.22.3.4.5.5.1MethodCONTENTSREVISIONSTATUSOFMETHODS .......................................LISTOFFIGURES(NUMERICORDER)..................................CROSSINDEX- SUBJECTS-TO-FIGURES................................SCOPE.............................................................COVERAGE..........................................................NUMBERINGSYSTEM................................................METHODNUMBERS....................................................DECIMALSYSTEM...................................................REFE8RNCED DOCUlf3NTS.............................................DEFINITIONS......................................................GENE8ALREQUIREMENTS.............................................DETAILEDREQUIREMENTS............................................INSTRUMENTSANDMRASURRMENTS- 100SERIES........................No. Method101.1- MeasurementofPotential.....................................102.1- Measurementoccurrent .......................................103.1- MeasurementofPower .........................................104.1- MeasurementofFrequency.....................................105.1- MeasurementofRe,si6tance....................................106.1- MeasurementsofTransientsandWaveforms .....................107.1- MeasurementofPowerFactor..................................108.1- MeasurementofTime ...........................................109.1- MeasurementofSpeed.........................................110.1- MeasurementofTemperature...................................111.1- MeasurementofWeightandForce ..............................112.1- MeasurementofPressure......................................114.1- Temperature Control (Hot Rooms)..............................114.2- TemperatureControl(Cold Rooms).............................114.3- TemperatureControl(Altitude Chambers)......................115.1- MeasurementofSoundLevel ...................................116.1-. .Determmatlonof PhaseRotation..............................117.1- DeterminationofPhaseRelationship..........................5.2 INSTRDlfiNTATION METHODS-200SERIES.............................MethodNo. Method201.1- ElectricalInstruments:CareInspection, Use, andRequiredAccuracy ...........................................202.1- ThermalInstrumentation......................................PAGEviviixi11111248:923323540505965697481828587909294979899102ivDownloaded from http://www.everyspec.com.. . . .. .MIL-HDBK-705C203.1- DataSheetsandRecordEntries ...............................205.1- GeneralInstructionsforConnectingTestingInstruments......220.1- EnginePressureMeasurements.................................220.2- PressureandTemperatureCorrectionstoSparkandCompressionIgnitionEngineData ...........................221.1- Temperature CorrectionstoResistanceMeasurements...........222.1- BatteryServicingandConditioningPriortoColdStartingTests ............................................6. NOTKSAND CONCLUDINGMATERIAL....................................APPENDIX A-LOADBANKS ................................................108110165166170171177178Downloaded from http://www.everyspec.com::.- :MIL-HDBK-705CREV1S1ONSTATUSOFMETHODSMethodNo. Revision Date101.1102.1103.1104.1105.1106.1107.1108.1109.1110.1111.1112.1114.1114.2114.3115.1116.1117.1201.1202.1203.1205.1220.1220.2221.1222.1----- -b----- -b----- -b----- -b----- -b----- -b---- --b----- -b----- -b----- -b----- -b----- -b----- -b---- --a---- --a---- --a----- -b---- --b---- --b---- --b---- --b---- --b----- -b----- -b----- -a----- -aReplacedby(ifMethoddeleted)viDownloaded from http://www.everyspec.com~~MIL-HDBK-705CFIGUP.SS101.1-1101.1-2101.1-3101.1-3.1101.1-3.2101.1-4101.1-4.1101.1-5102.1-1102.1-2102.1-3102.1-3.1102.1-4103.1-1103.1-1.1104.1-1104.1-2104.1-3104.1-3.1105.1-1105.1-2105.1-3105.1-4105.1-5106.1-1106.1-2106.1-2.1106.1-3106.1-4107.1-1107.1-1.1107.1-2108.1-1108.1-2RepresentativetypesofdcVoltmeters ..................Seriesresistancemultiplier ...........................RepresentativetypesofacVoltmeters ..................Representativetypesof acVoltmeters ..................Representativetypesof acvoltmeters ..................Acceptabletypeof recordingvoltmeter .................Acceptabletypeofrecordingvoltmeter .................Potentialtransformer..................................Acceptabletypeof self-containeddc ammeter ...........dc eumeterwithrotaryshunt ...........................Representativeacaimneters.............................Representativeac ammeters .............................ac ammeterused inconjunctionwith currenttransformer............................................Acceptabletypesofwattmeters .........................Representativetypesofwattmeters .....................Representativemeters formeasurementof frequency.....Representative meters formeasurementof frequency.....Acceptabletypeofrecordingfrequencymeter...........Acceptabletypeof recordingfrequencymeter...........Kelvinbridgefo,rmeasuring lowresistance .............Drop-inpotentialtestconnections.....................Comparisonmethod teatconnections.....................Wheatstonebridge formeasuringresistances ............Acceptabletypesofmegohmmeters ......................Typicaloscilloscope...................................Typiceloscillograph...................................Typicaloscillograph...................................Typicalharmonicanalyzer..............................Transientwaveformrecorder............................Power factormetere ....................................Power factor meters ...............................!....Phaseanglemeter ......................................Sampleoscillogramshowingmedianline.................Typicaloscillograph...................................9101112131415161920212223252629303132383940414247484950515556576061viiDownloaded from http://www.everyspec.com109.1-1109,1-1.1109.1-2110.1-1110.1-2112.1-1114.1-1114.2-1115.1-1116.1-1116.1-2201.1-1202.1-1202.1-2202.1-3205.1-1205.1-2205.1-3205.1-4205.1-5205.1-6205.1-7205.1-8205.1-9205.1-10205.1-11205.1-12205.1-13205.1-14205.1-15-, >.-..MIL-HDBK-705CFIGURES(corit inued)PAGERepresentativetypeofspeedandrevolutioncOunter...Representativetype ofspeedandrevolution counter...Representative hand-typetachometers..................Varioustypesof thermocouples........................Multiple-sensorautomaticdata-loggingsystem.........Representative typesofmanometers ....................Layoutfortypicalhotroom ..........................Scheinat icdiagramofcontrolledlowtemperaturechamber..................................................7172737980848689Soundlevelmeter ....................................Portablephaserotationindicators....................Makeshiftphaserotationindicator....................(Figuredeleted,blankpagemaintained)...............Immersedandexposedthermometers.....................Thermometerplacementformeasuringambientairtemperature whiletestingtwogeneratorsets..........Thermometersor thermocouples locationsformeasuringtemperature ofelectrolytein6-,12-and24-voltbatteries......................................Self-contained acvoltmeter ..........................acvoltmeterwithpotentialtransformer...............,.acvoltmeterwlth multiplier..........................Schematicdiagramofvoltmeterwithselectorswitchforlme-to-lme voltagemeasurements..........Potentialselectorswitch.............................Recordinginstrument withelectricdrive..............Self-contained dcvoltmeter...........................Self-contained acammeterwithprotectiveswitch......acammeterwithcurrenttransformer usingtaps........ac ammeterwithcurrenttransfOrmeruaingwrappedturns.........................................AUMIet er tranaferswitch...............................acammeterwithcurrenttransformers andselectorswitch................................................Self-contained dcarmneter.............................dcammeterwithahunt.................................Single-phaae wattmeter................................939596101105106107118119120121122123124125126127128129130131132. . .ViiiDownloaded from http://www.everyspec.comMIL-HDBK-705CFIGUSES(continued)205.1-16205.1-17205.1-18205.1-19205.1-20205.1-21205.1-22205,1-23205.1-24205.1-25205.1-26205.1-27205.1-28205.1-29205.1-30205.1-31205.1-32205.1-33205.1-34205.1-35205.1-36205.1-37205.1-38Single-phasewattmeterwithpotentialtransformer......Single-, phasewattmeterwithcurrenttransformer........Single-phasewattmeterwithpotentialandcurrenttransformer............................................Single-phasewattmeterwithwyeboxon three-phase,three-wue balancedsystem.............................Single-phasewattmeteron three-phase,three-wirebalancedsystemusing twocurrenttransformers.........TWO single-phasewattmeterson three-phaae,three-wiresystem......................................Two-element,polyphaaewattmeteron three-phase,three-wiresystem ......................................Two-element,polyphasewattmeteronbalancedthree-phase,four-wiresystem .......................................Twoelement,polyphasewattmeterwithpotentialtransformersonbalancedthree-phase,four-wiresystem.TWOelement,polyphasewattmeterwith currenttransformersonbalancedthree-phase,four-wiresystem.Twoelement,polyphasewattmeterwithbothcurrentandpotentialtransformersonbalancedthree-phase, four-wxresystem ............................................Threewattmetersusedonunbalancedthree-phase,four-wiresystem ............................................Polyphasewattmeterusedon single-phasesystem........Polyphasewattmeterwithcurrentandpotentialtransformersusedasasinglephaseinstrument.........Single-phasepower factormeter ........................Single-phasepowerfactormeterwithcurrentandpotentialtransformers.................................Three-phasepower factormeter .........................Three-phasepower factor meterwithpotentialtransformers...........................................Three-phasepower factormeterwithcurrenttransformer.Three-phasepower factormeterswithcurrentandpotentialtransformers.................................Single-element wattmeterusedasavarmeteron three-phasebalancedcireuit.................................PolyphaBevarmeter circuit.............................Frequencymeter ........................................PAGE13313413513613713?139.,.14U141142143144145146147148149150151152153154155ixDownloaded from http://www.everyspec.com- MIL-HDBK-705C205.1-39205.1-40205.1-41205.1-42205.1-43205.1-44205.1-45205.1-46205.1-47220.2-1FIGURZS(continued)PAGEFrequencymeterwithpotentialtransformer............. 156Recordingfrequency meter............................... 157Load instrumentationfortwo-wirydcgeneratorset ..... 158Load instrumentationforthree-wire dcgeneratorset... 159Loadinstrumentationforsingle-phase, two-wireacgeneratoraet.......................................... 160Load inatrumentationforsingle-phaae, three-wireacgeneratorset....................................... 161Loadinstrumentationforthree-phase, three-wireacgener~toraet ....................................... 162Load instrumentation forthree-phase,four-wireacgeneratoraet .......................................... 163Load instrumentationforshortcircuitcurrents........ 164SlingPsychrometer..................................... 169xDownloaded from http://www.everyspec.com.\, --tfIL-HDBK-705cCROSS-INDEX: SUBJECT-.TO-FIGURESSUBJECTORKEYWORDSAmmeter,acAmmeter,ac,Ammeter,dcAmmeter,dc,Ammeter,dc,Ammeter,dc,. . . . . . . . . . .. . . . . . . .. . . .. . . . . . .. .. .. .. .used/wcurrenttransformer .,..............................................self-contained ......................withrotaryshunt ...................with shunt ..........................Analyzer,harmonic ...............................Automaticdata-loggingsystem,multiplesensor ...Bridge,kelvin ...................................Bridge,Whetstone ...............................Connections,test,comparisonmethod .............Connections,test,drop-inpotential .............Counter,revolutionand speed ....................Counter,speedandrevolution ....................CurrentCurrentmeterCurrenttransformer,usewithac ammeter .........transformer,usewith power factor..........................................transformer,usedwithwattmeter .........Data-loggingsystemautomatic,multiple sensor ...Frequencymeter ..................................Generatorset, ac, single-phase,two-wire,loadinstrumentation ................................Generatorset,ac,single-phase,three-wire,loadinstrumentation ................................Generatoraet,ac, three-phase,three-wire,loadinetrumentation ................................xiPAGESFIGURBSARSON21,22,23,114,116,1182319,20, 119,12019,1192020,12050733841403964-6664-6623135,137,140123,124,130,133,1357329,144,145,146149150151Downloaded from http://www.everyspec.com- MIL-HDBK-705CCROSS-INDEX: SUBJECT-TO-FIGURES (continued)PAGESFIGURES SUBJECTORKEYWORDSARRONGeneratorset,ac,three-phase,four-wire,~........................two-wire,load........................three-wire,loadDad....... 163instrumentationGeneratorset,dc,instrumentationGeneratorset,dc,instrumentationHarmonicanalyzer158 ... .. . .159578616995,96. . . . ... . . . . ... . . . . .. . . .. . ... ... .. . . . ... . .. . ... . . .. . . . . .. . ... ... .Hotroomtypi~allayoutfor .......................Humiditymeasuringinetrument ....................Indicator,phaserotation ........................Kelvinbridge ....................................Line-to-line voltagemeasurements, voltmeterschematic diagramfor ..........................45121Loadinstrumentation .............................158,164Load instrumentation,acgeneratorset........... 160-163Load instrumentation, dcgeneratorset........... 158,159Lowtemperaturechamber,controlledschematicdiagramfor ....................................Manometer . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .Medianline,shownonoacillogram................898487496462,63Megohmmeter ....................................Meter,phaseangle ...............................Meter,powerfactor ..............................Meter,soundlevel .................................93Multiplier,usewithacvoltmeter ................Multiplesensorautomaticdata-loggingsystem ....Multiplier,seriesresistance ....................1208014276755,56,6854Multiplier,usewithdcammeter ..................Oscillagram ......................................Oscillograph .....................................Oscilloscope .....................................649695Phaseanglemeter ................................Phaaerotatinnindicator, makeshift..............Phaserotationindicator, portable...............xiiDownloaded from http://www.everyspec.comMIL-HDBK-705CCROSS-INDEX: SUBJECT-TO-FIGURES (continued)SUBJECTORKEYWORDS PAGESFIGURESAREONPotentialtransformerusedwith frequencymeter .......................................... 156Potentialtransformer,usewithacvoltmeter ..... 119Potentialtransformer,usewithpowerfactormeter .......................................... 146>148,150Potentialtransformer,usedwithwattmeter ....... 133,135,141,143,146Power factormeter ............................... 147-152Power factormeter ............................... 62,63Power factormeter, three-phase .................. 147,148Power factormeter, three-phase.................. 149-152Power factormeterwith currentandpotentialtransformers ...................................148,152Pres8uremeasuring instrument .................... 84Psychrometer .....................................169Recorder,transientwaveform .....................58Recordingdata-loggingsystem,automatic......... 80Recordingfrequencymeter ........................ 38,39,157Revolutionand speedcounter ..................... 71-73Schematicdiagram,controlledlowtemperaturechamber ........................................89Schematicdiagram,voltmeterwfselectorswitch ...121Selectorswitch,usedwithvoltmeterforline-to-linevoltagemeasurements..............121Shortcircuitcurrents,loadinstrumentationfor ............................................164Shunt,usewith dc ammeter.......................27,131Single-phasesystem,wattmeteruse...............145Slingpsychrometer ...............................169Soundleve1meter ................................93Speedendrevolutioncounter.....................71-73Tachometer,hand-type ............................73xiiiDownloaded from http://www.everyspec.comMIL-HDBK-705CCROSS-INDEX: SUBJECT-TO-FIGURES (centinued)SUBJECTORKEYWORDSPAGESFIGURESARIONTemperaturechamber,low,controlled,schematic diagramfor..........................89Temperature measurement,ambientair,dua1generatorsettesting..........................106)Testconnections, comparison method ..............47Testconnections, drop-inpotential ..............46Thermocouple .....................................79Thermocouplelocationformeasuring.batteryelectrolyte temperature ........................107Thermometerplacementformeasuringambientairtemperature ................................106Thermometer, exposed .............................105Thermometer, immersed ............................105Three-phasesystem,varmeteruse ................. 152Three-phasesystem,wattmeteruse ................ 136-144,153Three-phase,three-wireayatem,wattmeteruse .... 136,137,138Three-phase,four-wiresystem,wattmeteruae ..... 140-144Transformer, potential ........................... 22Unbalancedthree-phase,four-wiresystem,wattmeteruse .................................. 144Varmeter ......................................... 153,154Varmetercircuit ................................ 154Varmeter,polyphase .............................. 154Voltmeter with selectorswitch ................... 121Voltmeter, ac .................................... 15-17,118,119,120Voltmeter,ac,withmulitplier ................... 120Voltmeter,ac,wlpotentialtransformer ............Voltmeter,ac,self-contained ....................Voltmeter,dc ....................................Voltmeter,electrostatic, 30-Kv ..................Voltmeter, recording .............................Voltmeter, vacuum tubetype ......................Wattmeter ........................................11911812,1241920,211833,34, 132-146xivDownloaded from http://www.everyspec.comSUBJECTORWattmeter,Wattmeter,MIL-HDBK-705CCROSS-INDEX: SUBJECT-TO-FIGURSSKEYWORDSpolyphase .............................polyphaseusedas single-phaseinstrument .....................................Wattmeter,polyphase,with currentandpotentialtransformers ...................................Wattmeter,eingle-element ........................Wattmeter,single-phase ..........................Wattmeter,single-phase,useof twoon three-phase,three-wiresystem ..............................Waveformrecorder ................................Whetstone bridge ................................Wyebox,usedwithwattmeter .....................(continued)PAGESFIGURESAREON139-143,145,146146146153132-1381385848136xvDownloaded from http://www.everyspec.comMIL-HDBK-705C1. SCOPE1.1 Covera&. Thishandbook coverstwoseriesofmethods formeasuringanddetermining characteristicsofallelectricgeneratorsandgeneratorsetsaaclassifiedbyMIL-STD-1332,andassociatedequipment. .The illustration anddescriptionof thetest instrumentstogetherwith instructionfortheiruaeareincludedasapplicableunder eachmethod. As noted intheforewordnfthishandbook,someof theolder typesof instruments areno longermanufactured.1.2 Numb~ringsystemsused inthishandbook. Textherein isidentifiedinaccordancewith MIL-STD-962andthesampleformatsshowntherein. Methodandmethod figurenumbering isadditionallysignificantas follows:1,2,1 Methodsnumberedin the100series. Thesemethodspertaintobasicinstrumentaandmeasurements.1.2.2 Methodsnumbered inthe200seqiea. Thesemethodspertaintobaaicinstrumentationproceduresandapplications.1.2.3 Revisionstomethods- identification. Lower case alphabeticcharactersare suffixedtothemethodnumberstoidentifyrevisionstomethods.1.2.4 Figurenumberingwithinmethods. Thebeginningdigitsofanyfigurenumberarethesameas themethodnumberthatfigurepertainsto. Ahyphenisusedtoseparatethefirstand secondportionsofthefigurenumbers. Thedigitsusedinthesecondportionsof figurenumberseatabliahtheorderoffigures withineachmethod;where groupsofalternateormulti-pagefigureaoccur,suchaawhen depictingseveraltypesormanufacturer 1modeleofinstruments used fortbesamepurpose,thesecondportionofthe figurenumberissuffixed with adecimaloneachof thesecondandsubsequentfiguresinvolved. The decimalsestablishtheorderoftheaubaequentfigures withinthat~OUp.Certainof the figuresdepictmulti-purposeinstruments;thereforethereareseveralinstanceswhere thepictorialcontentoffiguresisidentical,andisusedtwiceormore,but tbefigurenumbersand titlesdiffer,dependinguponthecategoryormethodwhere thefigureoccurs.1Downloaded from http://www.everyspec.comMIL-HDBK-705C2. REFERENCEDDOCUMENTS2.1 Is.sueiof.. .d.ocurnents. Thefollowingspecifications andstandards oftheissueineffectondateof invitationforbids,orrequestforproposal,unlessadifferentissueisspecifiedintheprocurementdocuments,formapartofthishandbooktotheextentspecified herein.STANDARDSMILITARYMIL-STD-705MIL-STD-1332MIL-STD-1474GeneratorSets,EngineDrivenTestMethodsandInstructions.DefinitionsofTactical,Prime,Precise,andUtilityTernrinoloziesforClassificationof theDODMobileElectricPowerGeneratorSetFamily.NoiseLimits forArmyMateriel.(Copiesofspecifications andstandardsrequiredby contractorsinconnectionwithspecificprocurementfunctionsshouldbeobtainedfromEnginetheprocuringactivityorasdirectedby thecontracting officer. Copiesforotherpurposesmaybe obtainedfromNavalPublicationsandFormsCenter,5801TaborAvenue,Philadelphia,PA 19120.)2.2 Otherpublications. Thefollowingpublications of theissueineffeetondateof invitationforbidsorrequestforproposal,uqleasadifferentissueisspecifiedintheprocurementdocuments,formapartofthishandbooktotheextentspecifiedherein.AMERICANNATIONALSTANDARDSINSTITUTEANSIC2-NationalElectricalSafetyCode..ANSI C50.10thru C50.41Series-RotatingElectricalMachinery.ANSI/ASHRAE41.6-Standard Method forMeasurementofMoistAirProperties.ANSI/IEEE100- Standard DictionaryofElectricalandElectronics Terms.ANSI/NEMAMG1-MotorsandGenerators.ANSI/NEMAMG2 -SafetyStandardforConstructionandGuideforSelection,Installation andUseofElectricMotorsandGenerators.ANSI/NFPA70-NationalElectricalCode.(includedas generalreferences)(Copiesmaybe obtainedfromtheAmericanNationalStandardsInstitute, 1430Broadway,NewYork,NY 10018. Microformorcopiesarealsomaintainedatmanylibraries.)Downloaded from http://www.everyspec.comMIL-HDBK-705CAhXRICANSOCIETYOFHEATING,REFRIGERATINGANDAIR CONDITIONINGENGINEERS (ASHRAE).ASHRAE Handbook 1981Fundamentals,Chapter6,Psychometric Tables.AS.HRAEBrochureonPsychrometr~.(Copiesmay beobtainedfromASHRAE,GA 30329. Microform orcopiesarealsoChapter5,Psychometrics, andInc.,1791TullieCircleNE,Atlanta,maintainedatmany libraries.)2.3 Textbooks. The followingtextbooksare listedforinformation purposesandarenot tobe consideredasapartofthishandbook:ElectricalEngineers.Handbook,PenderandDelMar,Vol. 1,4thEd.,Wiley Brothers,IEEEStandardDictionaryofElectricalandElectronicsTerms,IEEE100Wilby - Interscience.Standard,HandbookforElectricalEngineers,FinkandBeaty,llthEd.,McGraw-Hil1BookCo,ChambersDictionaryof ScienceandTechnology(1978),HippocreneBooks.(Copies may be obtainedfrombookstores,or fromtbepublisherslisted;copiesarealsomaintainedatmany libraries.)Downloaded from http://www.everyspec.comMIL-HDBK-705C3. DEFINITIONS3.1 Extentandsourcesofdefinitions.ConsulttheANSI/IEEE100Standard,andotherreferencedocumentsofsection2herein.Downloaded from http://www.everyspec.comMIL-HDBK-705c,-...4. GENERALREQUIREMENTS4.1 Physicalstandards,conventionsandcali.bratio.n traceability. Primaryandsecondarystandards,conventions,andvalues forcalculations,computation,conversions,andcalibrationof instruments,shallbe thoserecognizedhy theInternationalElectrotechnicalCommission(IEC),International OrganizationforStandardization(1S0)and theUnitedStatesNationalBureauofStandards(NBS).TheIECand 1S0areboth locatedinGeneva,Switzerland. IntheU.S.A.,informationregardingall thesestandardsandconventionsmaybe obtainedfromNBS,Washington D.C.,20234.4.2 RecycledJvirginandreclaimed.materials. Reclaimed, recycled andrecoveredmaterials shallbeused,whereappropriate,tothemaximumextentpossible. Thishandbookdoesnot containanyrequirementsthatitemsbemanufactured fromvirginmaterials, solongas theintendeduseofany itemisnotjeopardizedthereby.5. DETAILEDREQUIREMENTS5.1 Instrum.entsandMeasurements- 100Series.5Downloaded from http://www.everyspec.com101.1.1potential101.1.2.:.: NIL-HDBK-705C.~ NETHOD101.lb.....MSASURENENTOFPOTENTIALGE.NERAL. Theterms,voltage~electromotive force,andareconsideredsynonymous herein.Il@IcATINGVOLTMETERS.101.1.2.1 DCVOLTAGE. Twotypesof instruments arerecommendedformeasuringdcvoltage-DAr60nval voltmetersanddigitalelectronic voltmeters(figure101.l-l). Digitalelectronictypesshouldnotbeusedtomeasuredcvoltagewhichalsocontainsan accomponentofanysignificance becauaesuchanaccomponentcanpreventthesetypesfromobtainingasteadyreading. BothDArsonvalanddigitalvoltmetersareavailableashigh-resistance Volt-metershavingfull-scale readingsatvaluesinthemicrovolt,andarealsoavailableas full-eiale,self-contained unitarangingashighas750volts.Voltmeterrangescanbe furtherextended,evenbeyond50,000volts,byconjunctive usewithexternally-attachedmultiplyingdevices(figure101.1-2).Suchdevices,commonlyreferred-toasseriesresistance multipliersandseries multipliers,areprecision-made, wire-woundresisters. Theyarecarefully manufacturedand calibratedtobeelectricallystablewithinspecifictolerances overrangesof temperature andperiodsoftime.Voltmeters,especiallymillivoltmeters,shouldnotbe connectedintocircuits havingvoltageshigherthantheratingoftheinstrument. Tomeasurevoltages higher thantheratingofarelativelylowresistanceinstrument, a0e7iea resistancemultipliertlmustbeusedwith it(figure101.1-2). Inthiscase,tbecorrectvoltageisobtainedby solving the followingequation:E. Vr(Rv+Rm)Rvwhere:E isthevoltagetobemeasured.V= istbereadingofthevoltmeter.Method101.lbDownloaded from http://www.everyspec.comRv istheresistanceof thedialoron thevoltmeterRm is theresistanceof theMIL-HDBK-705Cvoltmeter. (This maybe foundonthevoltmetercover.)seriesmultiplier. (This value isusuallystatedon the exteriorof theseriesmultiplierhousing.) Thisformula,solvedforRm,canbe used forselectingaseriesmultipliertobeusediftheapproximatevalue ofE isknown.Becauseof thehigh-inductive-voltagesurgewhichmaybendthepointeronDarsonvalanalogtypemeters, dcvoltmetersshouldbe disconnectedfroma fieldcircuitbefore thefieldswitchisopened.Becauseofhighalternating voltagesdevelopedby transformeractioninthefieldwindingsduringstarting,dcvoltmetersalsoshouldbe disconnectedfromsynchronous motorsorsynchronouscondenserfieldsbeforethemachinesarestartedfromtheac line.101.1.2.2 ACVOLTAGE. TWO typeof (RMS)sensingandindicating voltmetersareused tomeasureacvoltage. hesetypearedynamometer(figure101.1-3)anddigital(figure101.1-3.1and 101-3.2)typevoltmeters. Dynamometertypevoltmeterrangesusuallyarefrom7-U2 to750vO1ts.fullscale.DPamOmeter-typevoltmetersshouldnotbeusedoutsidetheirratedfrequencyrange.Digitaltypevoltmetersusuallyhavewiderrangesand inmanycasesareautoranging.101.1.3 RECORDINGVOLTMETERS. Recordingvoltmetersareusedtomeasuretransientsor time-varyingvoltages. Figure 101.1-4showsanacceptabletypeofMethod101.lb7Downloaded from http://www.everyspec.com.,, ,:,MIL-HDBK-705Crecording VOktmeter. Thistypeof instrument, TexasInstruments ModelPDSHKFHXVA-A16-XT, orGouldModel 2108-2202-005542, shallbeusedthroughoutthegeneratrmtestsgiveninMIL-sTD-705, unlesstherequirements of theprocurement, documentspecifically ,stateotherwise.-.101.1.4 POTENTIALTHANSFOHMERS. Potentialtransformers(figure101.1-5)areused fortwopurposes: toisolatethetestinginstruments fromthelinevoltage,andtoactasmultiplyingdevicesfortheinstruments.Toobtainsatisfactoryaccuracywhenusingapotentialtransformer,itshouldbeusedunderconditionsofvoltage,frequency, andvolt-anpereburdenthatthemanufacturerrated itfor.Method101.lb8Downloaded from http://www.everyspec.comMIL-HDBK-70SC9Method101.lbDownloaded from http://www.everyspec.comMethod101.lbMIL-HDBK-705CO:ocOooc0:0)00>000)0000>0)10CiIDownloaded from http://www.everyspec.comMIL-HDBK.70scMethod101.lbDownloaded from http://www.everyspec.comtiIL-HDBK.70scMethod101.lb12[o a u)* ADownloaded from http://www.everyspec.comt.iIL-HDBK-705cf.. -J13Method101.lbDownloaded from http://www.everyspec.comMIL-HDBK-705C69Method101.lb14Downloaded from http://www.everyspec.comMIL-HDBK-705C/II\\II,IMethod101.lb15Downloaded from http://www.everyspec.comMIL-HDBK-705C(DOo@FIGURE 101.1-5. Potential transformer.IHEiIlMethod101.lbDownloaded from http://www.everyspec.comMIL-HDBK-705CMZTHOD102.lbMSASURSFftNTOFCUFJUINT102.1.1 GENERAL. Currentisobtainedfromtheformulawhere I isthecurrentinamperes,E isthepotentialreadinginvolts,andR istheresistance inohms.102.1.2 INDICATINGAMMS~RS. Whenanyammeterisused inacircuithavingcyclicorvaryingcurrentlevels,suchaaexciterfields,itmustbe recognizedthattheaccuracyof theinstrumentiacompromisedby thesefluctuation, oftenby anamountthatrenders the instrument uselessfortheintendedmeasurement.Filteringdevicesare availableforminimizingtheeffectsof thesefluctuation.102.1.2.1 DIRECTCURRSNT. Forthemeasurementof directcurrent,analogDAraonval-typeordigitalammeteraareused. Self-containedinstruments ofthesetypesare availablewith full-scale readingafrom20microampere UD to30amperea-(figure 102.l-l).Digital ammetersareactuallydigitalvoltmetersused inconjunctioninternalahunttodisplaythemeasuredcurrentaaaaetofnumerala.Formeasuring currentbeyond thecapacityof theinstrumentathand,areused toextend therangeof themeters (figure102.1-2). Shuntsarewithanahuntaprecisionfour-terminalre;iatorsusedtomeaa&e currentbymeasuringthevoltagedropbetweenthevoltage terminals withthecurrentintroducedatthecurrentterminals. Shuntsarenormallycalibratedforaspecific millivoltdropata specificknown current. NhenDArsonvalmillivoltmetersareused inconnectionwith shunts,(asinanammetersystem),themillivoltratingofthemeter shouldbe thesameas thatoftheshuntatratedcurrentutilizingcalibratedleada.102.1.2.2 ALTERNATINGCURRENT. Forthemeasurementofalternatingcurrents(RMS)sensingand indicating meterssuchasdynamometers,iron-vanetypeanaloginstruments,anddigitalmeters (figures102.1-3)normallyareused. Bycnmbiningtheseinstrumentswith appropriate currenttranaformera, anyaccurrent measurementshaving practicalsignificance canbemade. Becauaeof thenonlinearcharacteristicsofmoat analogacammeteracalea,theyshouldnotbeused inthelowerportionof theirranges.Method102.lbDownloaded from http://www.everyspec.com-MIL-HDBK-705c102.1.3 CURRBNTTI@NSFOSMERS. Currenttransformers(figure102.1-4)areusedfortwopurposes;toisolate theinstrumentfromthelinevolta~e.andtoactasamultiplyingdevicefortheinstruments.--It,iadesirabletouse threecurrenttranaformera with threeammeters(oroneammeterandasuitab~etransferswitch)tomeaaurethethreelinecurrentsonthree-phase, three-wirecircuits(figure205.1-12). Iheuseof lessthanthreecurrenttranaforrqeraisu,aua.lly notcoat-effective, duetotimeconsumedchangingteatconnections,.andmay notprovidethedesiredlevelofconfidenceforacceptancetea.ting.CAUTION: ALLOWING.DIRECTCURRRNTTOFLOWINEITHERWINDING,MAYCAUSETHETRANSFORMER CORETO BECOMEMAG~TIZED AND IMPAIRTHEACCURACYOFTHEINSTRUMENT. INADDITION,DANGEROUSLYHIGHVOLTAGESMAY BElNDUCEDINTHESECONDARY WINDING(PHINARY OR SECONDARY),CAUSINGPOSSIBLEINJURYTOTSEOPEPJ.TORANDBFJ3AKDOWNOFTHEWINDINGINSULATION. IF~GNETIZATION ISSUSPECTEDORIFTHECALIBRATIONISNOTEVIDENT,THETRANSFORMERSHOULDBESUBMITTED TOAPROPERCALIBRATION FACILITYFORCERTIFICATION. INORDERTOOBTAINMAXIMUMSAFETYFOROPERATORS ANDAPPARATUS,0!?SSECONDARY TERMINALNUSTBEGROUNDED;THEMETALCASEORCORE,IFACCESSIBLE,MUSTBEGROU~ED; CONNECTIONSMUSTNOTBEMADEORCHANGEDWITHVOLTAGEON;THEPRIMARYOFTHETILiNSFOS$4ER MUSTBECONNECTEDINTHELINEANDTHESECONDARYTOTHEINSTRUMENTS, ANDNOTVICEVZRSA;ANDTRE SECONDARY OFTHETF@NSFORMER MUST Nw BEOPEWD WITHTHECURRENTFLOWINGINTHEPRIMARY. A SHORTINGSwTCH ACROSSTSSSECONDARYWILLBEPROVIDED. THISSWITCHWILLBEOPENEDONLYWHENTAKINGMSTERREADINGS. THISSWITCHNORMALLYWILLBEAPARTOFTHBCUBRENTTRANSFORMER.Method102.lb1sDownloaded from http://www.everyspec.comM1L-HDBK-705CrFIGURE 102. l-l, Acceptable type of self-containedde ammeter.EiEl19Method102.lbDownloaded from http://www.everyspec.comMIL-HDIIK-705cFIGURE02. I-2. I Dc ammeter with rotary shunt.E3EEil20Method102.lbDownloaded from http://www.everyspec.comMIL.HDBK-705C-m@0L9e0@0alMethod102.lbDownloaded from http://www.everyspec.comMII,.HDBK-70SCMethodIl)2_lh22Downloaded from http://www.everyspec.comMIL-HDBK-705CLMethodlo2.lb23Downloaded from http://www.everyspec.comMIL-RDBK-705CMETHOD103.lbMEASUREMENTOFPOWSR103.1.1 GENERAL. Mechanicalpowermostcommonlyisexpressedinhorsepower. cal powerordinarilyisexpressedinwatts.Thereisnopracticalprimarystandardofelectricpower,thewattbeingderivedfromthevoltandampere. However,expressed -10 Q-rboii55Method107.lbDownloaded from http://www.everyspec.comMIL-HDBK-705C - f=o.Method107.lb56Downloaded from http://www.everyspec.comMIL.HDBK-705CL\oJFIGURE 107.1-2. Phase angle meter,57 Method107.lbDownloaded from http://www.everyspec.com.J.#-MIL-HDBK-705C; METHOD108.lbMEASURKM31NTOFTIME108.1.1 GENERAL. Theprimarystandard oftimeintheUnitedStatesisbasedonastr-l observations madeby theNavalObservatoryatWashington,D.C. Timesignals basedonthesedeterminations aresentoutbyNavalRadioStations andby StationWWV of theNationalBureauofStandards. Secondarystandard clocksmaybependulumcontrolledorsynchronous clocksdrivenbyaconstantfrequency sourcesuchasatuningfork,orcrystaloscillator.Thesesecondary standards maybe checkedagainsttheObservatorytimebyusingtheradiobroadcasts.108.1.2 MSCw ICALTIf@.RS..Mechanicalclocksforlaboratory useusuallyareofthestopwatchkind. Theyarespecifically designedfor measuringtimeintervals oftheorderofanhouror less. The startandstopmechanismsofastopwatchandclockfrequentlycauseerrorsbecauseof lagor jumpingof thesweephandwhenthemechanismisoperated. It isfrequentlymore accuratetostartthewatchatapproximately10secondsbeforezeroandthenstarttheprocesstobe timedasthehand sweepsthroughthezero. Thepercentoferrorofastopwatchmaybeminimizedbymakingalltimeobservations at least1minutelong.108.1.3 ELECTKIC,AL..~hERSRS . Severaltypesofelectricaltimersareusedtomeasuretimeintervals. Themostcommonoftheseisthesynchronousstopclock. Thisdeviceoperatesinthesamemannerastbemechanicalstopwatcheedescribed aboveexceptthatthehandsarestartedandstopped by a smallmagneticclutchengagingthehandswitheithera synchronousmotordriveorabrake. Thus,theerrorsinvolvedinstartingandstopping aremuch lessthanthose ofthemechanicaltim??s. Electricaltimersofthistypedependuponthefrequencyofthepowersourcefortheirspeedandarenomoreaccuratethanthepowersourcetowhich theyareconnected. For thisreason,theyshouldneverbedriven bythepowerfromanengine-generator set.Digitalreadoutstopwatchesor timersarecommonlyusedduringgeneratorsettesting. Tnesedevicesutilizeverylowpowerdrainsolidstateelectronicsandmaybebatterypowered.Electroniccounters,utilizingcontrolledfrequencysupplies, arequiteoften used,especiallywhere therequiredaccuracyofthetimeintervalmeasurementishigh.108.1.4 OSCILLOGRAMTIMINGTRACES. Oscillograms(seefigure108.1-1)alwaysrequiresomesortoftimescaleifanymeasurementsaretobemadeonthem. Theprovisionofsuchascaleisquite simple withmostgalvanometerstypesofoscillographs. A standardfrequencyfromacrystalor tuningforkoscillator maybe impressedupontheelement,oracommercialpowervoltagemaybeusedasatimingtrace. Onanoscillogram, whenpositionistheimportantquantity ratherthantime,as inengineindicator diagrams,thetimingtracemaYMethod108.lb58Downloaded from http://www.everyspec.comMIL-HDBK-705Cbesuppliedby a contactoron theenginecrankshaft,orby amagneticpickupfroma slottedirondiskon thecrankshaft. Oscilloscopes(figure108.1-2) maybe provided with aso-calledZ-AXIScontrol.Thisactstoblankoutthetracewhena signalisapplied. Thus,aperiodicpulsemaybeused todotthetraceandconsequentlyshowtimeintervalsby thedistancebetweendots.Oscillo-scopeswithoutZ-AXIScontrolcanbemade to showadottedtraceby interruptingthesignalperiodically. This lattermethod ismuchmoredifficulttocalibrateandshouldbe avoided.whereverpossible.Method 108.lb59Downloaded from http://www.everyspec.comMIL-HDBK-7O5CSIMULATED DATA FOR ILLUSTRATIVE PURPOSES ONLY/TlMlN(3 WAVEFIGURE108.1-1 Sample oscil logram, showing median 1inc.mMethod108.lb60Downloaded from http://www.everyspec.comMIL-HDBK.70scuu1.N61Nethod108.lbDownloaded from http://www.everyspec.comMIL-HDBK-705CMS1HOD109.lbMEASUREMENTOF SPEED109.1.1 q. Speedofrotationisderivedbycountingrevolutions andmeasuringelapsedtime. Thisoperationmaybe performedveryaccurately bymeansofacounterandelectricclutch,automatically timedbya synchronousclockandastandardfrequencysource. Onecommerciallyavailabledeviceofthistypeiscalledachronotachometer andisshowninfigure109.1-1.Rotationalspeed maybe translatedtofrequency by theuseofanacgeneratordrivenby the.rotating ,element. Thisthenmaybemeasuredelectrically(see Method104.1).109.1.2 SPEEDCOUNTERS. Oneof theways tomeasurespeedduringa teatistocountrevo~measured timeinterval. Thismaybe donebyobservingthereadingaofacounterpermanentlyattachedtothemachineahaft,or by temporarily attachingacountertotheahaft,througha friction wheelordisk. Ineithercase,thedurationoftheobservationshouldbe greatenoughtominimizealltheerrorsdue tostartingandstoppingthestopwatchorcounter.In thecaseofaportablecounter,which, inuse, isstartedandstopped, eitherthecountershould be startedastheclockhandsweepsthroughzero,orviceversa. Noattemptshouldbemadetostartboththecounterandstopwatchsimultaneously.109.1.3 DIRECTBEADINGTACHOMETERS. Severalrnethodaareusedtoindicatespeeddirectly. Amongthemarethepositionofcentrifugalflyballs, thevoltageofamagneto,thepressureof acentrifugal hydraulicpump,photocellsensors,andtheeddy-currentdragofarotatingmagnetonaconducting disk.Eachofthesedevicesmaybeusedasatachometer, andeachhas itsownadvantagesanddisadvantages. Directreadingtachometers areavailable eitherforpositiveconnectiontothemachineundertest,orforhanduse. Thelatterareshowninfigure109.1-2.Chronographs orrecordingtachometers arespeedrecordinginstruments inwhichagraphicrecordof speedismade.Intheusualforqs,therecordpaperi8drivenatacertaindefinitespeedby clockworkorweights,combined withaspeedcontrolled motorordevicesuchthataspecificdistanceofcharttravelrepresents adefinitetime. we penwhichmakes therecordmaybeattachedtothearmaturesofelectromagnets, servo-driven,oroperatedonaproportionalelectricalsignal. we speedsensingpickupmayconsistofamechanicallycoupledtachometer generatororamagneticproximitydevicewhosefuncti6n istogenerateavoltage,themagnitudeof frequencyofwhichissuppliedtotherecorder. Somerecordersacceptelectricalsignalsdirectlyfromtheacgeneratoroutputandrecordthefrequency onthechartasa corresponding speed(revolutions perminute).Method 109.lb62Downloaded from http://www.everyspec.com?lIL-!rDBR-705c109.1.4 STROBOSCOPES. Stroboscopicmethodsarec:,tciall. y suitablefor..---,-.determiningthespeedofmachine p-rtsvbi.cllarenot ~?adiiyacceseii~le,whereitisnot practicable.to,w. er!echal!i.c~l methods,orEotroomsusedtotestgeneratorsetsmusthaveadequatetemperaturecontroltomeet therequirementsofthehightemperaturetest. The averegeambientairtemperatureshallnotvarymore than3 Cthroughout thetest,asmeasuredby thermocouplespIacedinaccordance withMethod 202.1. A typicalhotroom,capableofmaintainingsuchtemperaturecontrolisshowninfigure114.1-1. Thehotroomshallhaveprovision to heattheintakeair,torecirculateacertainamountoftheheatedair,toadmitfreshair,tokeepalltheair intheroomcirculatingandtoallowtheexcessheat andengineexhauattoescape. Therecirculatedairshallnotreturnwithinthehot room,butshallbe conducted.aroundthechamberinaseparate duct.114.1.3 SIZEOF .HOT.ROOM.Thehot roomshallbe largeenoughsothatthewalla areatleast6 feetaway fromthegeneratorset undertest, with theexceptionthatiftheroomhas aninnerscreenorfalaewallwiththeairpaasingonbothsidesaothatitisuniformlyat thehotroomambienttemperature, thisscreenor!Ifalaelt wallmay be lessthan6feet,butnot lesethan3feet,fromthegeneratoract. Inthiscase,theouterwallmaybeasclosetothescreenor Ifalsewallasdesired,providedthattheambientairismade tocirculatebetweenthescreenor*ifalaewallaud theouterwall. Itmayaleobenecessarytouseairbafflesanddeflectorsintheroomtomaintaingoodtemperature andairflowcontrol,and,as longaathebafflesanddeflectorsareatnearlythesametemperatureastheambientair inthehotroom,theymaybeplacedclosertothegeneratoraetthan6feet. Theroomshallbeat least3feethigher,insidedimension,thanthegeneratorsetbeingtested.114.1.4 AIRCIRC Theairinthehotroomshallbe incontinuousmotiontopreventtheformationof localconditions,hotorcoldspots,withintheroomwhicharedifferentfrogtheaveragen theroom.However,thechamberairvelocityshallnotexceed5mph. Airvelocitiesgreaterthan5mph areallowableprovidedtheincreasedvelocitiesarenecessarytomaintaintheepecifiedchambertemperature but inno instanceshal1thevelocityexceed15mph. Ingeneral,itiseasiertocontroltheconditionsinthehotroomiftheair flowie fromthegeneratorendof thesettowardtheenginecoolingairexhauat. ,114.1.5 SAPETY. Aviewingportshouldbe installedtoallowvisualinspection of thegeneratorsetwithoutenteringthechamber.Carbonmonoxide(CO)andexploaivemixturesdetectoreandameans toshutdowntheaetinanemergentyarealsorequired. Workingpereonnelshouldbe awareofconditionswithintheteatchamberpriortoentering.Method114.. lb78Downloaded from http://www.everyspec.comMIL-HDBK-705CLouversforCOtItrOlMultispeed . , Of intoke ~rPLAN VIEW- -ShuttersClosed when ~alhoust Fens ore notgyuse 1#mm2EwSECTION A-AFIGURE114.1-1. Layout fortypicalhocroom.EEl79Method114.lbDownloaded from http://www.everyspec.comMIL-HDBK-705CMETHOD114.2aTEMPERATLJRECONTROL(COLDROOMS)114.2.1 GENE&iL.Testchambersinwhichconditionssuchastemperature,humidity,andatmosphericpressureareaccuratelycontrolled arecalledenvironmentalchambers. me environmental chamberstobeconsideredinthishandbookarehotroomsj!,tcoldrooms!!,and!Ialtitudechambers,,.114.2.2 CONTKOLOFTEMt.EKATUKE. Coldroomsusedtotestgeneratoreetsmusthaveadequatetemperaturecontroltomeet therequirementsof thecoldtest. Theaverageambientairtemperatureshallbeuniformwithin3Cthroughoutthetestasmeasuredby thermocouples placedinaccordancewithMethod202.1. A typicalcold,room,capableofmaintainingsuchtemperaturecontrolisshowninfigure114.2-1. Thecoldroomshallhaveprovisionsto dryandchilltheintakeair,torecirculatethechilledair,tok~epall thesirintheroomcirculating, toremovetheheatgeneratedby theeet,and toallowtbeengineexhausttoescape.Anestimateoftheamountofheatgeneratedbya generatoreetoperstingatratedloadis1/3ofthetotalheatasusefulpower,1/3asexhaustheatand1/3asenginebest toberemovedby theenginecoolingeystem. Thisistrueforsparkorcompressionignitionenginee. Foroperationinacoldroomtheexhaustsystem mustbevaportight,notonlyduetothepoisonousgasesbutbecauseevena slightleakwillemitwatervapor totheroomwhichwillfreezetothecoolingcoils,thusloweringtheabilityof thecoilstotransfer heat. Inadditiontobeingvaportighttheexhaustsystemmaybe insulatedto preventexcessive heattransfertotheroom.The freshairintaketothechambermusthaveprovisions todryairenteringthecoldroomaswellaschillittotheambienttemperature of thecoldroom.A suggested methodofdryingtheairistopassitthroughdrysilicagel. Theairdryer musthavesufficientcapacitytosupplydryairforthedurationoftheoperational portionof thecoldtest(s). Dryairisdefinedasairhavingadewpointofatleast3C less thanchamberambient.114.2.3 SI.~.OFCQ,LDROOM. Thecoldroomshallbe largeenoughsothatthewallsareatleaat6 feetawayfromthegeneratorsetundertest,withtheexceptionthatiftheroomhas aninnerscreenor false wallwiththeairpassingonbothsidessothatitiauniformlyatthecoldroomambienttemperature, thisscreenor! falsewallmaybe lesethan6 feet,butnotlessthan3feet,fromthegeneratorset. Inthiecase,theouterwallmay beasclosetothescreenormfal~e,tWalIasdesired,providedthattheambientairiemade tocirculate betweenthescreenorfalse wallandtheouterwall.Itmayalsobenecessarytouseairbafflesanddeflectorsintheroomtomaintaingondtemperature control,and,as longas thebaff}esanddeflectOrs areatn@arlYthesametemperature astheambientairinthecoldroom,theymaybe placedclosertothegeneratorsetthan6 feet.Theroomshallbeat least3feethigher,insidedimension,thanthegeneratorsetbeingtested.Method114.2a80Downloaded from http://www.everyspec.comMIL-HOBK-705C114.2.4 AIRCIRCULATIONINCOLDROOM. Theair inthecoldroomshallbe incontinuousmotion toDreventtheformationof localconditions,hotorcoldspotswithintheroomwhich aredifferentfromtheaverageintheroom. Itisrecognizedthatlargequantitiesofairmust becirculatedthroughthecoolingcoilsinordertoremovetheheatgeneratedby theequipmentundertest;how-ever,anyairmovementgeneratesheatwithin thecoldroomandtheoptimumconditionof airflowwithin thecoldroommustbe foundindividuallyforeachcoldroomdesign.114.2.5 ATMOSPHEREWITHINCOLDROOM. Theambientatmospherewithinthecoldroomshall,atall times,bechillednormalair. Atno timeshalltheroombecooledby thedirect injectionofcarbondioxide(C02)oranyothergasorliquidotherthannormalair. Shouldtheatmosphereof theroombecomecontaminated by any foreigngaawhichcanaffeettheresultsof thetest,thetestshallbe suspended,theroomclearedof theforeigngasandthetestrestarted.114.2.6 SAFETY. Aviewingportshouldbe installedtoallowvisualinspectionofthegeneratorsetwithoutenteringthechamber. Carbonmonoxide(CO)andexplosivemixturesdetectorsandameanstoshutdownthesetinanemergencyarealsorequired. Workingpersonnelshouldbeawareofconditionswithintheteetchamberpriortoentering.Method114.2a81Downloaded from http://www.everyspec.comMIL-HDBK-70scIIOTC : TUER1 SHOULDU lIIREC WINDOWS ON CACMSIDCLEGEND@ EMOINE011iAU91 COMNIT3TIOH@ .IRCULA71N6.n *..@ lCWIN,L BOARDFORTHERMkLINSTRUMENTATIONCONDUITFOR TltERMAL#N5TRUMEM1AT,0WIHWWINPALSCWALL7 !3%LEAPSli-V!_l-.~ ~ WINDOWTHROU31,.3.L.TION1-mfmmm, @ TERMINALBObRDFOR GENERATORLEA.LINESAND INETWMENT LEADSY 2 d ;Ez:?FIGURE 114.2-1.}4ethod114.2a@REFR1OCRAN1 COILS@ ADJUSTABLE WUVERSFOR,070,0, A.,- , ,9*@ ,wWNOITIOHER FOR wIIRCJJ .~ nUMID!TVANDT#.WCRATURC 0? K ..E-, .,,Schematic diagram of controlled low temperature chamber.m82Downloaded from http://www.everyspec.com,: !,,MIL-HDBK-705CMETHOD114.3aTEMPERATURECONTROL(ALTITUDE CHAMBERS)114.3.1 GENSR4L. Testchambersinwhichconditionssuchas temperature,humidityanderic pressureareaccuratelycontrolledarecalledenvironmentalchambers. Theenvironmentalchamberstobe consideredinthishandbookare hotrooms, Icoldrooms,andIaltitdechamber~t;.114.3.2 CONTROLOFTEMPERATURE. Altitudechamberaused totestgeneratorsetsmusthave adequatetemperature controltomeet therequirementsof thealtitudeoperationtest. Theaverageairtemperatureshallbeuniformwithin3Caroundtheset,and itshallnotvarymorethan3 Cthroughoutthetest,aameasuredby 8thermocouplesplacedinaccordancewithMethod202.1. Thealtitudechambershallhaveprovisionstoheattheintakeair,torecirculateacertainamountof theheatedair,tokeepall theair intheroomcirculating,toridthechamberofexcessbest, toridthechamberofengineexhaustwhilemaintainingtheexhaustbackpressureat thesamevalueas itwouldbe ifitwasexhaustingintothechamberproper. o114.3.3 SIZEOFALTITUDECHAMBER. Thealtitudechambershallbe largeenoughsothatthewalla areat least6 feetawayfromthegeneratoraetundertest,with theexceptionthatifthechambarhaaaninnerscreenor falsewallwiththeairpassingonboth sidesof itsothatitiauniformlyat thechamberambienttemperature,thisscreenorfalsewallmaybe lessthan6 feet,butnot lessthan4.5 feet,fromthegeneratorset. Inthiscaee,theouterwallofthechambarmay beasclosetothescreenor Ifalsewallasdesired,providedthattbeambientchamberairismade tocirculatebetweenthescreenor falsewallandtheouterwall. Inadditiontothelnadingdoortothechambersomemethod (air-lock)shallbe providedtoanterand leavethechamberwithoutaffectingthechamberambienttemperature orvacuum. Itmay alsobenecessarytouseairbafflesanddeflectorsinthechambertomaintaingoodtemperaturecontrol,and,as longasthebafflesanddeflectorsareatnearlythesametemperatureas theambientair inthechamberanddonot interfere withtheambientairthermocouples,theymaybeplacedclosertothegeneratorsetthan6feet. Theroom shallbeat least3feethigher,insidedimension,thanthegeneratorsetbeing tested.114.3.4 CONTROLOFPRRSSU~ . Ameansofcontrollingandmaintainingthepressureof thechambermustbe provided. Tbepreaaureshallbe controlledtowithin~50 feetof thespecifiedaltitudevalue.114.3.5 AIR CIRCULATION. Theairinthealtitudechambershallbe incontinuousmotion topreventtbeformationof localconditionswithinthechamberwhich aredifferentfromtheaverageinthechamber. Ingeneral,itiseasiertocontroltheconditionsinthechamberiftheair flowisfromthegeneratorendof thesettowardtheenginecoolingairexhaust.Method114.3a83Downloaded from http://www.everyspec.com-- ;MIL-HDBK-705C114.3.6 =. Aviewing port shouldbe installedtoallowvisualinspection ofthegeneratorsetwithoutenteringthechamber. Carbonmonoxide(CO)andexplosive mixturesdetectorsandameanstoshutdownthesetinanemergencyarealaorequired. Workingpereonnelshouldbeawareofconditionswithinthetestchamberpriortoentering. Anemergencyrelief valvetobringtheairpressuretotheoutsideambientpressurethatiaoperationalfrominsidethechamber,andsomemethodof limit$ngthevacuuminsidethechambershouldbeprovided.QI+ethod114.3a84Downloaded from http://www.everyspec.comMIL-HDBK-705cMSTHOD115.laMEASUREMENTOF SOUNDLEVEL115.1.1 GENE~. Forsomeapplicationsitisdesirablethatanengine-~~generatorsetoperateasquietlyaspossiblewithoutimpairingitsoperatingefficiency. Somemanufacturingspecifications containrequirementsforlimitsofoperatingnoise; in termsofunitaof standardreferencesoundlevel. Thestandardreferencelevelisdefinedas0.0002microbar (apressureof0.0002dyneper squarecentimeter)at 1,000Hertz.115.1.2 SOUNDLEVELM?ZTSR.A soundlevelmeter (figure115.1-1)iaaninstrumentforreading,intermsofastandardreferencesoundlevel,thesoundlevelat itsmicrophone. fieinstrumentconsistsessentiallyofamicrophone,electronicamplifyingand filteringequipment,octavebandanalyzerandanindicatingmeter calibrator. TheAmericanNationalStandardsInstitute(ANSI)StandardsforthesemetersincludethoselistedinMIL-gTD-1474foroctave,half-octave,and third-octave band filtersets.This instrumentisextremelysensitivetosoundfromanysource. Therefore,toaccuratelydeterminethenoisecharacteristics ofageneratorset,thetestshouldbemade inaquietruralareawheresourcesof soundotherthanfromtheunitunder testareat aminimum.Method115.la85Downloaded from http://www.everyspec.comMIL-HDBK-705C.7-7In,86Method11S.laDownloaded from http://www.everyspec.comMIL-HDBK-705CMETHOD 116.lbDETERMINATIONOFPHASEROTATION116.1.1 (XWR&4L. During anycycle,an acvoltagevariesfromzerovoltstoamaximum,tozero, toaminimum,and finallybacktozero.Wheneachof thevoltagesofa three-phasesystemareobservedsimultaneously, itianotedthatthetimeofarrivalatthemaximumvoltageofeachphaseisdifferent.Ifphaseonereachesamaximum first,followedby phasetwoandthenphasethree,thephaserotationis 1-2-3.Ifphaseonereacheamaximum,followed by phasethreeandthenphasetwo,thephaserotationia 1-3-2. Thisorientationoftheleadsiaimportantsincea three-phasemotorwill runinonedirectionwhenconnected1-2-3,andinthereversedirectionifconnected1-3-2. Moreover,iftwogener-atorsetsaretobe operatedinparallel,thephaserotationof theconnectionsrauatbe thesameforbothsets,ora shortcircuitwilloccur.116.1.2 PHASEROTATIONINDICATORS.116.1.2.1 MOTORTYPE. A threephaseacmotorwithadiscorragfaatenedtotheshaftto-the directionofrotation,whose leadsaremarkedtoshowwhichare 1,2and3,andwhosedirectionofrotationisknownwhenlead1isconnectedtophaseone, leadtwoisconnectedtophasetwoandlead3isconnectedtophasethree,may beused.116.1.2.2 PORTABLEINDICATORS. TWO typesofportableindicators areavailable. The firsttypeisessentiallya smellmotorwhosespeedofrotationislowandwhose directionofrotationisknownandeasilyseen. Thesecondtypeconsistsofanelectricalcircuitwith twoneontubesappropriately inter-nallyconnectedsothatoneor theotherwill light,dependinguponthephaserotation. Bothof thesetypesare illustratedinfigure116.1-1.116.1.2.3 MAKESHIFTINDICATOR. Phaserotationmaybedetermined byconnectingtwosetsof twolampbulbsinseriesbetweencorresponding terminalsof thetestgeneratoranda sourceof threephasevoltageofthesamefrequencyandaknownphaserotation. The thirdterminalof thetestgeneratorshallbeconnecteddirectlytothethirdterminalof thesource(figure116.1-2). Ifthephaserotationof thegeneratoristhesameas thatofthesource,thelampswillblinksimultaneously. If thephaserotationisnot thesame,thelampswillblinkalternately.Method116.lbS7Downloaded from http://www.everyspec.comMIL-HDBK-705CMethod116.lb88Downloaded from http://www.everyspec.comMIL-HDBK.70sc( A)ll SING THREE-PHASE SOURCE OF KNOWN PHASE ROTATION120VOLTLAMPSJ aTO 3-PHASE TO 3- PHASE STATION POWER GENERATOROR 3-PHASE20a ~OLTS208 VOLTS!FOR WHICHGENERATOR-PHASE ROTATIONPHASE ROTATION-T i~ IS BEINGOF WHICH IS1208 VOLTS 208 VOLTSDETERMINEDKNOWN! ~,4 *t1t120VOLT LAMPSFIGURE 116.1-2. Makeshiftphase rotationindicator.m89Methodl16,1bDownloaded from http://www.everyspec.com\ ..-.!-iiiL-HDBK-705CMETHOD117. lbDETERMINATIONOFPHASERELATIONSHIP117.1.1 GENERAL. Twoormoreacgeneratorsetsmay beoperatedinparallelprovidedthat-( 1)phasesequences,(2)voltagesand (3)frequencies arethesame. Theusualmethodofdeterminingthattwoormoresetsareinphaseiethedimmingoftheparallelinglights. However,somegeneratorsetscontainparallelingaiddeviceswhichmustbe testedtodeterminetheexactphaserela-tionship betweenthesetstitthetimethesetsareallowedtoparallel.117.1.2 ~SE ANGLE.-. Thephaseanglemeteremployspulsemeasurementof thedifference.intimebetweenzeroandcrossoverofthecomparedvoltages.,The phaseanglemeterdifferentiates theinputwavesandthedifferencesignaliadisplayedon adirectreadingmeter inelectrical.degrees.117.1.3 OTHER.MKTHODS. Itispossibletodeterminephase .relationahipinvariouswaysusinginstrumegtsotherthantheaforementionedtypes. Theseothermethods include, butarenot limitedto,theueeofOscilloscOpes; hOwever,theset-ups,procedures and interpretations ofresultsof theseOthermethOdsareusuallycomplex. Beforeelectingtouseanyothermethod,carefulconsiderationshouldbegiventoitaacceptability,ease ofcOmprehenaiOn andPOtentialfOrmisinterpretation. Ifsuchamethod iaintendedtobeusedforgovernmentacceptanceorqualificationtests,priorapprovalofsuchuseshouldbeobtainedthroughthegovernmentcontractingofficerasearlyintheprogramaspossible.Method117.lb90IDownloaded from http://www.everyspec.comMIL-HDBK-705C5.2 INSTRUFSSNTATIONMETHODS- 200SERIES Method117.lb91Downloaded from http://www.everyspec.comMIL-HDBK-705CMETHOD201.lbELECTRICALINSTRUMENTS: CARE,INSPECTION, USE,ANDREQUIRED ACCUIGiCY201.1.1 GE~RAL. The following requirementsapplicabletoinstruments andequipmentcommonly used inthetestingofenginegeneratorsetashallbecomplied with.201.1.2 .CA~.INSPECTIONAm USEOFINSTRUMENTS. The following precautions..~PPIYIngeneraltO.theuse Ofelectricalinstruments andthosemechanicallnatrumenta, employmg Jewelbearings,smalloperatingtorques, ordelicatemovements.Beforeanyinstrumentiaused,itshouldbe inspectedtodeterminethatthepointerisfreeandrestsat zero,ifapplicable. Noinstrument shallbeusedthatsticksorbindsatanypartofthescale,orhasazeroerror.Instruments containingpermanentmagnetashallneitherbecarriedthroughnorplacedinstrong magnetic fieldsbecausetheaccuracyoftheinstrument maybeaffected,Cahleacarrying high currentstoan instrument,ornearit,shallbekeptclosetogetherandmustneverbe placedonoppositesidesof ironorsteelobjects,especiallyiftheyarerestingonan ironorsteelsurface.An instrument shouldreadthesameineachof fourhorizontalpositions, 90degreesapart,ifitiaunaffectedby strayfielda.Instrumentashouldnotbe dropped,bumpedagainsteachother,orplacedontablesorbenchesusedforsuchworkashammering,chipping,orriveting. Steelpivotsrestingonjewelbearingssupportthemovingpartsofmost instrumentsandthepressuresexertedon thejewelbythepivotinsuchabearingisusuallYoftheorderof severaltonspersquareinch. Forthisreason,shoc~andvi- -brationcaneasilydamagejewelbearingsand causeerroneousreadings.Instrument coverglasaeashouldneverbe cleanedorrubbedwithadryclothbecauaeofthedangerofbuilding,upa sta$icelectricchargeon theglaaa. Ifacoverglassbecomescharged,itmaybedischargedbyrubbinggentlywithadampcloth,orbymoisteningitwith thebreath. Ineithercase,nomoistureshouldbeallowedtocollectinsidetheinstrumentcase.Careshouldbe takentoavoiderrorsdue toparallaxwhenreadinganyinstrument. Recordinginstrumentsshouldbe calibratedandreadon thechartpapergraduation ratherthanontheindicatorscale./Method201.lb92Downloaded from http://www.everyspec.comMIL-HDBK-705CActual instrumentreadingsshallbe enteredonalldatasheetsandallcurvesshallbe carefullyplotted. Readingsshallneverbecorrectedforinstrumenterrors, transformerratios,or scale factorsbeforebeingenteredonthedatasheeta. When it isdesirabletohave truevaluesappearon thedatasheet,twocolumnsshallbe used; the firstfortheactualinstrument reading,and thesecondforthecorrectedvalue.201.1.3 ACCURACYOF INSTR(l_~NTS . Indicatinglaboratory-type electricalinatrumentareferredtointhishandbook,andillustratedinsection100,shallhaveanaccuracyat ieaat0.5percentof fullscale. Instruments willbeselectedand connectedtoiudicatein theaccurateportionoftheirrange.Digitalmeters generallyoffergreaterresolutionthantheanalogmodelstheyreplace. ForMIL-STD-705testing,threesignificantdigitsarerequiredforallelectricalmeasurementsunlessadditionaldigitaareneededforclarityordefinitionfortheapplicableteat.201.1.4 PROCURElfENTDOCUMENTREQUIREMEWS . Oneof thefollowingitemsmustbe specifiedin theindividualprocurementdocuments:a. Accuracyof instrumentsused foracceptancetestingshallbeinaccordancewithMIL-HDBK-705,Method201.1.b. Accuracyof instrumentsused foracceptancetestingshallbe inaccordancewith (theindividualprocurementdocumentshallsyecifythedocumentor clause Xoverning accuracyof instruments) . .Method201.lb93Downloaded from http://www.everyspec.comMIL-HDBK-705CMETHOD202.lbTHESMALINSTRUMENTATION202.1.1.GENERAL. Thermalinstrumentationincludesinstructionsforlocating varizsuring devicesfordeterminingtemperatureofcomponentsandmaterials,andthesurrounding(ambient)air.Theusualmethodsofobtainingtemperatures at thevarious locations are:contact,resistance,ore&beddeddetector. Eachofthesetemperature measure-mentmethodsarediscussedindetailinMethod110,1.202.1.2 GEWE.~TOR.. SETCOMPONENTS:202.1.2.1 CONTACTMETHOD. Thecontactmethodoftemperature measurementisusedinthe followinglocations: generatorbearinghousingorhousings,gen-eratorframe,statorcoils,intakeandexhaustcoolingair,collectorrings,commutator, poletips,rotorwindings,andenginecoolantand lubeoil (byimmersingthedetector). Temperature measurementsonmovingcomponentamustbeattachedimmediatelyoncethemovingpartisatrest.202.1.2.2 RESIST~C3E.METHOD. @ismethodisapplicableformeasuringthetemperature of thegeneratoroutputwinding,thegeneratorfieldandexciterfield. Itshallnotbeused onarotatingwindingwhosereaiatanceatambienttemperature isleasthan1,0ohm.Theapplicationnf thedevicesand theformulaforcalculatingthetem-peraturerisearegiveninMethod110.1.202.1.2.3 EMBEDDEDDETECTOR.METHOD. Usually,onlygeneratorsetsratedat500 kW,or larger,areequippedwithembeddeddetectorsforthedetermination ofthetemperature of theelectricalwindings. Ihetemperature of stationerywindingewillbemeasuredperiodically by thiemethodduringatest,whilethatofrotatingwindingswillbe takenata standstill, immediatelyfollowingshutdown.Embeddeddetectorsareoftwotypes: thethermocouple typeandtheresistancetype. Eitherofthesetypesmaybe employed as stationary oxrotatingdetectors.Beforemeasuringtemperatures by theembeddeddetector method,make surethatthedetectorscavebeenproperiylocatedinprocurement document.202.1.3 E.NGItfS COMPONENTS. All temperaturecomponents normallyusethecontactmethod. Thethethermocouple typeortheresistancetype.accordance with theapplicablemeasurementsof theenginecontactdetectorcanbeeitherMethod202.lb94Downloaded from http://www.everyspec.comMIL-HDBK-705C202.1.4 MBIENT AIRTEMPERATURE.202.1.4.1 APPARATUS. Ambientairtemperature measurementsshallbemadewithof thermometersor thermocouples. Thesedevicesshallbe exposeddirectlytotheambientair. Nhen chambersareused, thethermalsensingdevicesusedforcontrollingthechambertemperatureshallbe separatefromtheapparatususedformeasuringandrecordingthechamberambient.202.1.4.2 LOCATION.202.1.4.2.1 ENVIRONMENTALCHAMBERS. Precautions willbe takentoinsurethatnoneof thethermometersor thermocouplesarelocatedineitherhot*orIcoldspotsinthechamber. Thetherm6meteraor thermocouplesshallbeplacedatthefollowingpositions:Unhousedgeneratorset-Theambientairtemperature shallbemeasuredatadistanceof approximately2 feetdiagonallyoutboardfromthecornersofthegeneratorsetas theairapproachestheaet. Aminimumof2thermometers orthermocouplesshallbe recordedandaveragedtoestabliahtheambientairtemperaturespecifiedin theapplicabletestdocument. Iledistancefromwallsorobstructionsshallbe 1footminimum. Thetemperature measurementdevicesshallnotbe locatednear theengineexhaustoutletor inthecoolingairexhaustfromthegeneratorset.Housedgeneratorsets-The ambientairtemperatureshallbemeasuredatthegeneratorair intaketothehousing. Thismeasurementshallbe takenby aminimumof 2thermometersor thermocouples. Theoutputashallberecordedandaveragedtoestablishtheambientairtemperaturespecifiedintheappropriatetestdocument.202.1.5 CONTROLPANELTEFfPERAT.U~S . The temperature withinthecontrolpanelenclosureshallbe takenbymeansof athermocouple. ThethermocoupleMethod202.lb95Downloaded from http://www.everyspec.comMIL-HDBK-705Cishallbemountedin the spacebehindthecontrolpanelandshal1be solocatedthat itiasurroundedonlyby airandisnot incontactwithanyobject.Whentestingageneratorsetonwhichthecontrolpanelhasbeenopenedforin-spection,alwaysclosethecontrolpanelbeforemeasuringthetemperature oftheenclosurebehindit.202.1.6 BATTERYELECTROLYTE ANDBATTERYBOXAk@IENTAIRTEMTERATURJIS .202.1.6.1 BATTERYELECTROLYTE TEMPERATURES. Thebatteryelectrolytetemperatureshal1be takenbya thermometer orthermocoupleintheopeningtoacentralbatterycellinallbatteriee,ifthereiamorethanone. Nbenathermocoupleiaused, itshallbeenclosedwitha,. corrosionresistantmaterialwhich isflexible and sealedontheend inthebattery. Onesuchcorrosionresistantmaterialia!Teflon)t.To inatal1thethermocouple halfwaydowntheplates,awoodenseparatoraboutthethicknessofthethermocouple canbecarefullyforceddownbetweentheplates,thenthethermocoupleinstalled andtheseparatorremoved. Thethermocouple junctionshallbe locatedsothatitiscompletelyimmersedintheelectrolyte. Theplateswillhold thethermocoupleinplace. Ifathermometerisused,itshallbe locatedsothatitabulbiscompletelyimmersedintheelectrolyte..202.1.6.2 BATTERY.. BOXAMBIENTAIR,TEMPERATUKES.Thebatteryboxambientairtemperatures shallbemeasuredbymeana oftwothermocoupleslocated atOP?OsitesidesOfthebatterybOx,apprOximacelyhalfwayUP theinside wall,andfreefromcontactwith anyobjectotherthantheambientair.202.1.7 ~NTERIZATION HEATERTEMYERATURf$S .202.1.7.1 COOLANTTYPE HSATERS. Forwinterizationheatersthatheatandcirculatetheenginecoolant,thetemperature ofthecoolantshallbemeaauredatboth itsinletandoutlettotheheater. Thetemperatureshallbetakenbythermometers or thermocoupleslocated@ thepipingatthesepoints.202.1.7.2 HOT,AIRTYPEHEATERS. Forheatersthatheatandcirculateuncontaminated hot air,thetemperature of theairshallbemeasuredatitsinletandoutlettotheheater.hetemperatures shallbemeasuredbythermocouples locatedintheheaterductsat thesepoints.202.1.7.3 EXHAUSTGASMEASUREMENTS..~ OFHEATERS). Theheaterexhaustgastemperatureshallbemeasuredbya thermocouple locatedascloseaspossibletothepointatwhichtheexhaustgaaesleavetheheater. Nhentheexhaustgasisusedinheatingtheoilpan,thetemperature of theexhaustgas,afterpassingthroughor aroundtheoilpan,shallalaobemeasured.Method202.lb96Downloaded from http://www.everyspec.comMIL-HDBK-705cMSTHOD203.lbDATA SHEETSANDKSCORDENTRIES203.1.1 $ENE~L. Testsdonotfulfilltheirpurposeunlessaccuratedataarerecorded.Nhen thedataarecompareddirectlywith therequirementsofdocuments,orwhencalculationsaremade fromtheinformationoncompleteandtheprocurementthedatasheeta,andtheresultscomparedtotherequirementsof theprocurementdocuments,theacceptanceorrejectionof thesetunder testisdependentuponthedataobtained.To.avoidaccepting.equipmentwhich failstomeet therequirementsof theprocurementdocuments,andtobeabsolutelycertain that anyrejectsfailtomeettheserequirements,repeatanytestprocedureifthereisanydoubtas to( theaccuracyoftherecordeddata.Eachdata sheetmust be trackabletoacompleteseriesof information whichwill identifythesetunder testandthe testmethod,inadditiontothedata,The followingiswillbe included1.teat.2.3.inatruments4.TheThea listofinformation eachdatasheetshallbe trackabletooronthedatasheet:make,rating,modelnumber,andserialnumberof thesetundernameandnumberofthetestmethod.Columnsforallinstrumentreadings,withtheserialnumberoftheused,andthemultiplyingfactor.Thedateonwhich thetestnumberand thetimeof eachreading.5. Thenamesof thepersonnelGovernmentinspector.isperformed,theconsecutivereadingperformingthetestandtheobserver/ortheunitServices6. Noteaasnecessarytoclarifytheconditionsof thetest.7. Thenameor designation of theagencyresponsibleforinspection ofunder teat, Forexample: Philadelphia Region-DefenseContractAdministration.8.dataat theof3.Data sheetnumber.sametime,eachdataIfmore thanonedatasheetisusedtorecordsheetusedshallbenumbered,e.g.,sheet2Method203.lb97Downloaded from http://www.everyspec.com9. Theambient10. ReferencesMIL-HDBK-705Ctemperature reading.byreadingnumbertoattachedcharts.11. A seriesof instrument readingstakenwithinfiveminutesafterstartingtheset (onlyfor tests requiringstabilization oftheeet).NOTE: Zeroinstrument readingawillbe recordedas such. Donotleavethespaceblank.All instruments shallbe carefullyread. Thereadingsshal1berecordeddirectlyon thedatasheetandnotmultipliedby themultiplyingfactor beforerecording. Bothmaximumandmininnqoreadingsforcyclicvaluesshallberecordedonthedatasheets.Whenmakingreadingsforsteady-state conditions, be certainthattheseconditions havebeenreachedbeforerecordingthereadings.Noerasuresofreadingsshallbemade. Errorsshallbeneatlycrossedoutwithasinglestraightline. Consecutive readingnumberswillbeginwith thefirsttestconductedduringfiratarticle(reproduction) tests andshallbecontinuedthroughoutthesetests.Individualtestsrequiringa seriesofdatapointsshallberepeatedifaninterruption occursduringthetest(e.g,,datapointsbeingtakenforplottingacurve,etc.).Complete,eccurateandneatdataareessential whenperformingthetestsinMIL-STD-705.Samplesofdatasheetsformany testmethodswillbe foundinMIL-STD-705.The formatofeachshallbe followedsofaraapossible,tofacilitate theobtainingofcomparativedata.Method203.lb98Downloaded from http://www.everyspec.comMIL-HDBK-705CMETHOD205.lb..GENERALINSTRUCTIONSFORCONNECTINGTESTINGINSTRUFfdNTS205.1.1 GENERAL Instrumentusageisof criticalimportanceinthedetermination-- quantitativevalueofeffectsoccurringduringtests. Iftheapparatus isimproperlyconnected,theresultingdatawilleitherbeuselessorqualitativeatbest.On thefollowingpagesareinstructionsandschematicdiagramsindicatingthemethods ofconnectingthemostconmonlyused instruments requiredduringtheperformanceof themethods containedinMIL-STD-705. Itisrecognizedthattheterminalpostsofallinstrumentsarenotin thesameplaceas thoseshowninthediagramsandjudgementmustbeexercisedinconnectionofanyspecificinstrument. Themanufacturersinstructionsshouldalwaysbe consultedincaseof doubtas totheproperutilizationofany testapparatus.The generaltheoryofoperationof theinstrumentsshowninthediagramaiscoveredin the100Seriesofmethodsof thisHandbook. When recordinginstru-ments are required,theyaretobeconnectedintothecircuitinthesamemanneras shownforindicatinginatruments.205.1.2 CALIBIViTIONOF.,INSTRUMSNTS.All testinstrumentsshallbecalibratedatmaximumintervalsof6months toinsurstheiraccuracy. Testinstrumentsshallbe calibratedwithin30dayspriortothestartofanynewteatprogram. Instrumentsusedincalibrationshallhaveat leastfivetimestheaccuracyof theinstrumentbeingcalibrated. Calibratedreferenceinstrumentsof lesseraccuracythanstandard,whicharenotusedforanyotherpurpose,may beused fortherequiredperiodiccheckof testinstruments. Thecalibrationofall instrumentsshallbe traceabletotheNationalBureauofStandards.Instrumentsshallbe calibratedat thefrequenciesatwhich theyaregoingtobeused.205.1.3 >ELECTIONOF INSTRUMENTS. Priortoconnectinginstruments intocircuits,thoughtshouldbe giventotherangeofreadingswhichwillberequired. Therangeof theinstrumentshouldbegreatenoughsothatitwillnotbeburnedoutduringnormaluse,but therangeshouldnotbesogreatthatthereadingwillbe aolowon thescaleas tomaketheaccuracyofreadingunreliable. Onanalogdc instruments,thereadingsshallnotbemadeonthelower15percentof thescale. Onanalogacinstruments,thereadingsshallnotbemade on thelowerone-thirdof thescale.Instrumentalionaccuracyshallbenotlessthan ~0.5percentofthefullscalevalue,unlessotherwisespecifiedhereinorintheprocurementdocument.Method205.lb99Downloaded from http://www.everyspec.com., TD LDADBANKTYPEAC ammeter with current transformers and selector switch.Downloaded from http://www.everyspec.comMIL-HDBK.70sc70+LOAD+-o- 500Olo250FGLSHORTING SWITCHFI GURE 205. 1- 13. Self-contained OCanmeter.m119Method205.lbDownloaded from http://www.everyspec.comMIL-HDBK-705CCALIBRATED LEADS/-t6aQDCAM-PIECE OF PAPER AFFIXEDTO INSTRUMENT SHOWINGMULTIPLYING FACTOR.FI GURE 205. 1- 14. DCamneter with shunt.mMethod 205. lb120Downloaded from http://www.everyspec.comMIL-HDBK-705C1,I ITO LOAD.t603tET LOAD TERMINALSo:&AC - DC1+WM@FI GURE205. 1- 15. Si ngl e phase wattmeter.m121Method205,1bDownloaded from http://www.everyspec.comSET LOADMIL-HDBK-705CTERMINALSLINELTO (aa LINE aPTTO METERIIIFI GURE205. 1- 16.Method 205. l bTOLOAD+=11PIECEOFPAPERAFFIXED/ TO INSTRUMENT SHOWINGMULTIPLYING FACTOR.Si nqle-phase wattmeter with potential transformer,m122Downloaded from http://www.everyspec.comMIL-HDBK-705CSET LOAD TERMINALSi -TO LOADI0 c)f 100Q C.T~20 50010SEC~+- 0- ?1PIECE OF PAPER AFFIXEDTO INSTRUMENT SHOWINGMULTIPLYING FACTOR.FI GURE205. 1- 17. Si ngl e- phase wattmeter wi thcurrent transf ormer.123lHzlMethodZoS.lbDownloaded from http://www.everyspec.comMIL.HDBK-705C1SET LOADTERMINALS4P-rMETER*TO LOADL3qJj*agPIECE OF PAPER AFFIXEDTO INSTRUMENT SHOWINGMULTIPLYING FACTORFI GURE205. 1- 18. Si ngl ephase wattmeter wi th potenti al and current transf ormer.k@-JMethod20S.lb124Downloaded from http://www.everyspec.com.....--.,-.n.r-.MIL-HU151i-/U3LI0;t-.!3zrno-Method205.lb.-.Downloaded from http://www.everyspec.comMI L. HDBK- 70 SCblSET LOADTERMINALSTO LOAD*Qo0100+100;C.%c) OC.T o20 50 20 500 010 10* SECQ-o-q~ SECLpoq==!7PIECE OF PAPER AFFIXEDTO INSTRUMENT SHOWINGMULTIPLYING FACTOR.-tFIGURE 205.1-20. Sinqle-phase WBtt IiIete P on three-phase, three-wtrebalancedsystemUS$nqcurrenttwotransformers.mMethod205.lb,126Downloaded from http://www.everyspec.comMIL-HDBK-705C(L23PHASE-3 WIRESETLOADTERMINALSmFTOLOAD,F]GIJRE205.1-21. Twosingle-phase WattMeters on three-phase, three-wire system.m127 Method Zos.lbDownloaded from http://www.everyspec.comMIL,.HDBK-705CI>LISET LOADTERMINALSTO LOADFI GURE205. 1- 22. Two- el ement,pol yphase wattmeter on three-phase, three-wire system.mMethod 205.lb17RDownloaded from http://www.everyspec.com0 -1i+16adm J3Method205.lb129Downloaded from http://www.everyspec.comN -1A-i!!!!MIL-HDBK-705CIIIMethod205.lb130,Downloaded from http://www.everyspec.comMI L- HDBK- 705CSETLOADTERMINALSibkL2TOLOADrCT0020 50010SECFI GURE 205. 1- 25.uSEC~uTwo-e 1ement, polyphase wattmeter with current transformerson balanced three-ph ase, four-wire system.m131Method 205.lbDownloaded from http://www.everyspec.com,;MIL-HDBK-70SCAIIaOgF:+-id=IIgoii+1I,.AIEia+1aW+I000>()-e-zoem~om>+1acm+loId+ao1III0%f+l-~dIIo l-o10+1-1z&4$Method205.lb132Downloaded from http://www.everyspec.comMIL-HDBK-705CN -11II1I.4I111Method205.lbDownloaded from http://www.everyspec.com,-. .MIL.HDBK-~05CSET LOAD TERMINALSi-TO LOADFI GURE205. 1- 28. Pol yphase wattmeter used on single-phase system.mMethod205.lb134 Downloaded from http://www.everyspec.comMIL-HDBK-70scSET LOADTERMINALSTO LOAD1o10* EC-FfJM-1FIGURE 205. 1- 29. Pol yphase wattmeter with current and potential transformers usedas a single-p base Instrument.135Method205.lbDownloaded from http://www.everyspec.comM1L-HDBK-705CSET LOAD TERMINALS1br,.Method205.lb1VLWUJ+(3DFI GURE 205. 1- 30. Si ngl e- phase power f actor meter.m136Downloaded from http://www.everyspec.comMIL-HDBK-705CSET LOAD TERMINALSIFII*o 0+DCC. T.0020 50m- 2OmaoI1+1?1,TO METER+-11-r)FI GURE205. 1- 31. Si ngl e- phase power f actor meter wi thpotenti al and current transf ormers.m137 MethodZ05.lbDownloaded from http://www.everyspec.comMIL-HDBK-705CSET LOAD TERMINALS1 -LOoIFI GURE205. 1- 32. Three- phase power f actor meter.mMethod205.lb138Downloaded from http://www.everyspec.comMIL-HDBK-705C Z !!! 10-1k! N J iitQBMethod2T5.lb139Downloaded from http://www.everyspec.comSET LOADTERMINALS. .. . . ...MIL-HDBK-705CIw LII Iw@c)1000 C.To50 20010i sEcOQFI GURE205. 1- 34. Three- phase power f actor meter wi th current transf ormer.Method 205. l bEmzl140Downloaded from http://www.everyspec.comMIL-HDBK-70scI\ILISET LOADTERMINALS:SECD(T*1000 C.T. O50 20To LoAD)LFI GURE205. 1- 35.Three- phase power f actor meter wi thpotenti al and current transf ormers.l Xl zzzl141Method205.lbDownloaded from http://www.everyspec.comET LOAD,., .,,.MIL-HDBK-705cTERMINALSL2FI GURE205. 1- 36. Si ngl e- el ement wattmeter used as avarmeter on three-phase balanced circuit.mMethod 205.lb142Downloaded from http://www.everyspec.comMIL-HDBK.70scL2 0 -1I-.I I I I I I I I I IbII IIPia--LJI\IIII1--------1I. Ino Nm143Method205.lbDownloaded from http://www.everyspec.comMIL-HDBK-705CUNEIMethod205.lb>1150FMFIGURE 205.1-38. Frequency Meter.144Downloaded from http://www.everyspec.comMIL-HDBK-705CThF! T.TO METER~FI GURE 205. 1- 39. Frequency meter wi th potent i al transf ormer.145Method205.lbDownloaded from http://www.everyspec.comMI L- HDBK- 705C&----=-I(IC8RECORDINGFREQUENCYMETER/CONNECTTOOUTLET SUPPLIEDBYPUBLICUTILITY, UT QENSET CONVENIENCEOUTLET.FIGURE205.1-40Method205.lbRecording frequency meter.m146Downloaded from http://www.everyspec.comMIL-HDBK-705CII+J!!!k!&,u)+1O* L.-1NJy x147Method2os~lbDownloaded from http://www.everyspec.comMIL.HDBK-705CMethod205.lb148Downloaded from http://www.everyspec.comMIL-HDBK-705C*b149Method205.lbDownloaded from http://www.everyspec.comMIL-HDBK.70sc!!&JI ---t-lJliwlJ.~WgagMethod205.lb150Downloaded from http://www.everyspec.comMIL.HDBK-705C9:9r I&ia%!+mIMethod205.lb151Downloaded from http://www.everyspec.comMIL&lBK-7oscMethod205.lb1s2Downloaded from http://www.everyspec.comMIL-HDBK-70scPRIME MOVER!? I=mlmiii--75T2ACAMFOR WYE - CONNECTED FORDELTA-CONNECTEDGENERATORS GENERATORSFIELD CONNECTIONSASABOVEFORSINGLE PHASEGENERATORSTIFIGURE 205.1-47. Load instrumental ion for short circuit currents.m153Method 205. l bDownloaded from http://www.everyspec.comMIL-HDBK-705CMETHOD220.lbENGINEPRESSUREM?,ASUREMENTS220.1.1 GENERAL. ~e location of thepressuretapisofimportanceintherepeatabilityzine pressure measurements.220.1.2 AIRINT@ PRESSURS.220.1.2.1 SPARKIGNITIONENGINES. Theintake manifoldpressureshallbemeasuredby amanometerconnectedtoapreseuretaplocatedapproximately2inchesfromthecarburetorflange. Onsmallengineswhereapressuretapmayinterferewithcarburetion,theintake manifoldpressuredatamay.beomittedatthedeacretionof thetestingagency. Thepressureshallbemeasuredin inchesf at? 20ormercury (Hg).220.1.2.2 COMPRESSIONIGNITION ENGINES. Pressureoftheintakeairinthemanifold fornaturallyaspiratedenginesshallbemeasuredbyamanometerconnectedtoapressuretapneartheinletflangeofthemanifold. Forengineewith scavengingairblowers,turbocharged, or supercharges, theairpressureshallbemeasuredbyamanometerconnectedtoapreaauretaplocatedonthedischargesideof theblower. Thepressureshallbemeasuredininchesofwater(H20)ormercury (Hg).220.1.3 E~UST GAS PRESSURS. Themeanexhaustgaspressureshallbemeaeured.byamanometerconnectedtoataplocatedapproximatey 2inchesbeyondtheoutletflangeof theexhaust manifoldor turbocharger.Thepressureshallbemeasured ininchesofmercury(Hg)o!water ( H20) . Theback pressurei mposed b, y the l aboratory or manuf acturer s pl ant exhaust system duri ng tests atrated net continuousloadandapeedshallnotbe lessthanthatexistingatthesameloadandsDeedwith thesetexhaustingdirectlytotheatmospherethroughitsownexhaustsystem,highertestpressureisandwillbe increasedabovethisminimumspecifiedintheprocurement documents.value ifaMethod220.lb154Downloaded from http://www.everyspec.comMIL-HDBK-705CMethod220.2bPRESSURSANDTEM?ERATURZCORRECTIONSTO(SPARKANO COMPRESSIONIGNITION)ENGINEDATA. .....220.2.1 ~. Ambientairpressure,watervapor pressureandtheintakeairtemperaturevariationshave considerableeffecton tbeoperationalcharac-teristicsof engines. It isnecessarytocorrectforthesevariationsinordertoassurethatengineoutputdataisuniform.220.2.2 MEASUREMENTOFATMOSPHERICMOISTURS. ~,equantityofm0i8turemixedwith theairunderdifferentcondition8of temperatureanddegree8ofsaturation may bemeasuredinseveraldistinctlydifferentways. M&y ofthese,however,arenotpracticablemethodsfordaily0b8erVati0U8,.orarenotsufficientlyaccurate. Probablythemoat convenientof allmethod8andtheonemoat generallyemployedistoobservethetemperatureof evaporation--that ia,thedifferencebetweenthetemperaturesindicatedbywet-bulbanddry-bulbthermometers. Oneof themostcommonlyused instrumentforthispurposeistheslingp8ychr0meter (alsocalledwhirledpsychrometer). Inspecialca8es,rotaryfansorothermeansmay beemployedtomove theair rapidlyoverthethermometerbulbs. I nany case, satisfactoryresultscannotbeobtainedfromobservationinrelativelyStagnantair. A strongventilationisab801utelynecessarytoaccuracy.Additional informationonatmosphericmoisturemeasurementcanbe foundinANSI/ASHRAE41.6and intheASHRASbrochureonp8ychrometry.220.2.3 SLINGPSYCHROMETER.DE.SCRIPTION.Thisinstrumentc0nsi8tsofapairofthermometers,providedwithahandleas 8howninfigure220.2-1,whichpermitsthe thermometerstobewhirledrapidly,thebulbsbeingtherebystronglyaffectedby thetemperatureofandmoistureintheair. Thebulb of thelowerofthetwothermometersi8coveredwith thinmu81in,whichshaIlbewetatthetimeanobservationismade.220.2.3.1 MAINTENANCEOFTHEWETBULB. l%emuslincoveringforthewetbul b shal l be kept cl ean and i n good condi ti on. The evaporati on of thewaterf rom the musl i n al ways l eaves i ni ts meshes s smallquantityof 801idmaterial,whicheventuallystiffensthemuslinsothatitdoesnotreadilybecomewetafterbeingdippedinwater. Tominimizethi8problem,usepuredi8tilled waterandrenewthemuslin frequently. Newmuslinmust alway8bewa8hed toremovesizing(starch)andotherpotentialcontaminant beforebeingu8ed. A smallrectangularpieceofmuslinwideenoughtogooneandone-thirdtimesaroundthebulb,and longenoughtocoverthebulbandthatpartof thestembelowthemetalback, shallbe thoroughly wettedincleanwater,andneatly fittedaroundthethermometer. Itshallthenbe tiedfirstaroundthebulbatthetop,usingsuitablystrongthread,thenloopedtoformaknot.arOundthebOttOmOftheMethod220.2b155Downloaded from http://www.everyspec.comMIL-HDBK-705C.bulb,justwhereit beginstoroundoff. As thisknotisdrawn tighter andtighterthethreadwill slipofftheroundedendofthebulbandneatlystretchthemuslin covering with it,atthesametimesecuringthelatterat thebottom.220.2.4 M&NG -~OBSERVATION USINGTHESLINGPSYCHROMETER. Thewetbulbshallbe,thoroughlysaturated withwaterbydippingitintoasmallcuporwide-mouthedbottle. Thethemiometersshallthenbewhirledrapidlyfor20seconds;stoppedandquicklyread,thewetbulbfirst. Thesereadingsshallberecorded,thepsychrometerimmediately whirledagainanda secondsetofreadingstaken. .Thiaisrepeatedthreeor fourtimes,ormore, ifnecessary,untilat leasttwosuccessivereadingsofthewetbulbagree,therabyshowingthatithas reacheditslowesttemperature.Aminuteormoreisgenerallyrequiredtosecurethecorrecttemperature. Whentheairtemperature.ienear thefreezingpoint,thetemperature of thewetbulbmay fallseveraldegreesbelowfreezingpoint,but thewaterwill stillremaininthe liquidatate. No errorresultsfromthis,providedtheminimumtemperatureisreached. If,however,as frequently happens,thewatereuddenlyfreezes,a largeamountofheat isliberated, andthetemperatureof thewetbulb immediately becomes32. Insuchcaaesitisnecessarytocontinuethewhirlinguntiltheice-covered bulbhasreachedaminimumtemperature.220.2.4.1 NHIRLINGAm STOPPINGTHEPSYCHROMETER. It iscliff iculttoeffectuallydescribethese movemente. Thetechniques canonlybe learnedbypractice, Pnearmieheldwith theforearmabouthorizontal,and thehandwellin front. Apeculiarswingstartsthethermometers whirling,andafterward themotion iskeptupbyonlya slightbutveryregularactionofthewrist,inharmonywiththewhirlingthermometers. Therateshouldbe anaturalone,soastoba easilyandregularly maintained. Iftoofast,or irregular,thethermometersmay bejerkedaboutinaviolentanddangerouemanner. Thestoppingofthepsychrometer, evenattheveryhighestrates,canbeperfectlyaccomplished inaeinglerevolution, when onehas learnedthetechnique.Thiscanonlybe acquiredbypractice. Itconsistsofaquickswingoftheforearmbywhichthehandalsodescribesacircularpathandfollowsafterthethermometers inapeculiar mannerthatwhollyovercomestheircircular motionwithouttheslightestshockorjerk. As analternativestopping method,thethermometers may,withoutverygreatdanger,beallowedsimplytostopthemselves; thefinalmotionineuchacaeewillgenerallybequitejerky,but,unlesstheinstrumentisallowedtofallonthearm,orstrikessomeobject, noinjuryshouldreeult.220.2.4.2 SPECIALPROCEDURESFORUSINGTHEPSYCHRO~TER IN.SUNLIGHT.Whilethepsychrometer willgivequiteaccurateindications, eveninthebrightaunahine,observations made inthesunshinearenotwithoutsomeerror,and,wheregreateraccuracyisdesired,thepsychrometer shoqldbewhirledintheehedeofabui~dingortree,or,asmay sometimes benecessary,underan ,Method220.2b.156Downloaded from http://www.everyspec.comMIL-HDBK-705Cumbrella. Inallcasesthereshouldbe perfectlyfreecirculationof theair,and theobservershouldfacethewind,whirling thepsychrometerinfrontofhisbody. Itisagoodplan,whilewhirling,tostepbackandfortha fewstepstofurtherpreventthepresenceof theobserversbody fromgivingrisetoerroneousobservations,220.2.5 CORRECTINGINTAKSMANIFOLDPRESSUREOBSERVATIONS. Themoisturevaporpressureforagivencombinationof temperatureandrelativehumidityshallbedeterminedby obtainingwet-bulbanddry-bulbtemperatures withaslingpsychrometer. Thepsychrometershallbeoperatednear theengineairintakeandthereadingsobtainedshallbeusedinconjunction with theASHRASHandbook1981Fundamentals,chapter5and thePsychometric Tablesof chapter6 therein,toobtainthemoisturevaporpressure. Subtractthemoisturevaporpressurefromtheobservedvalueof themanifoldpreseuretoobtainthedryabsolutemanifoldpressureat theobservedtemperature. Thedryabsolutemanifoldpressureattheobservedtemperatureshallba convertedtoadryabaolutemanifoldpressureatthestandardcarburetorinlettemperatureof60 F(15.5C)by aPPIYingthefollowingformula:[-lD.A.M.P. atTs =D.A.M.P. atTo 460+ 60To +460Nhere:D.A.M.P. istheDryAbsoluteManifoldPressure.Ts isthestandardcarburetorinletairTo istheobservedtemperatureinF.temperature(60F).220. 2. 6 CORRECTINGMAKIMUMPOWBRVALUES. Al1valueaofobserved maximumenginegeneratorsetoutputpowershallbe correctedtostandardconditionsofpressureandtemperature(sealeveland60 F),unlessotherwisespecifiedintheprocurementdocument. Correcttheobservedenginegeneratorsetoutputvaluebyapplyingthefollowingformula:Correctedwatts= (Observed watts)29.92r460+T (Forsea leveland60F)-%%- &noNhere: Bis the barometer i nches of mercury ( corrected f or temperature) .Ei s thewater vapor pressure ( inchesofmercury),T istheintakeairtemperature(F).Method220.2b157Downloaded from http://www.everyspec.comMIL-HDBK-70SC. ,..,,,,.\Method220.2bIf158C(J$NDownloaded from http://www.everyspec.comDownloaded from http://www.everyspec.com;.MIL-HDBK-705CMethod222.laBATTERYSERVICING ANDCONDITIONASSU&iNCEPRIORTO COLDSTARTING TESTS222.1.1 GENEML. Lead-acidornickel-cadmium(NI-CAD) batterieaareusedtostarteomee-driven electricalpowergeneratorsets. Oneof thepurpoaeaofMIL-HDBK-705iatoprovideguidancetoassurethatproperteatconditionsandpreparationaareaccemplishedprior.tocommencing anyoftheMIL-STD-705tests.Nbenproviaionsaremade inadvancetoaasurethatadequatefacilitiea,equipmentandpersonnel willbeavailable, batteryservicingandconditionassurancecanusuallybeaccomplished withinanormal5-daywork-week. PlanningandschedulingforMIL-sTD-705testingshouldallowsufficient pre-testtimeforthesetaaka.The testsofMIL-STD-705,whenusedforfirstarticleorproduction acceptance,aretoverifythatgeneratorsetshavebeenproperlymanufactured, nottoteatbatteries. Batteriesaremulti-useitemstestedandqualifiedundertheirownseparate programs,priortobeingspecifiedforuaeongeneratorsetsorvariousotherequipment. BatteriesthatareusedduringMIL-ST.D-705firstarticleorproduction acceptancetestingare,inessence,testsupportequipment. Iffullbatteryoutputcapabilityisnotaasuredpriortogeneratorsettesting,inadequate batteryperformance maycauaeabortionofanotherwise validteatsequence;thiscanresultinwaatsoftestfacilityandpersonnelresources,andriskfailuretomeetcontractorprogramschedules. Operational experiencewiththeprocedures belowiathattheyarehighlyeffectiveinpreventingsuchproblems.NhenthetestsofMIL-STD-705areused forevaluation duringequipmentrasearcbanddevelopment, theuseornon-useoftheproceduresbelowdependsuponthepurposeforwhichthetestdatawillbeused. Forexample,totalsystemreliability oroperationalreadineasasaesaments, evaluations ofcomponentcompatibilities, standardization studiesandaoforth,wouldprobablynotrequiretheuseof thesebatteryconditioning procedures.222.1.2 PRRPAFuiTI.ON OFBATTERIES y~.Itis8tronglyrecommendedthatnewbatterieabeusedforthecoldstartingtestsofMIL-STD-705,tofurther minimizepossibilitiesoftestabortionsduetoimproper batteryconditions. Extremecaremustbe exercisedtoinsurethatNI-CADbatteriesarenotcontaminated by tools,equipment,solutions orgasesfromlead-acidbatteries. Suchcontamination candestroyNI-CADbatteries. RefertotheNI-CAD battery techni cal manual or manuf acturer a data f or f urther gui danceabout thi s.Batteries maybereceivedineitherthewetordrycOndition. Wetbatterycellsalreadycontaintheelectrolytesolution, whereasdrybatteriesrequirefilling withelectrolytesolutionafterreceipt. Somebatteries mayhaveMethod222.la160Downloaded from http://www.everyspec.comMIL-HOBK-705Csealingdevicesovereachcel1forshipmentandstorage,whichmustbedislodged(andcanbediscardedor leftinsidethecells)priortofilling. Wetbatteriesmayrequiretoppingoffwith dietilledwater tobringtheelectrolytetoitscorrectlevel,but neither toppingoffofwetbatteriesnor fillingofdrybatteriesshouldbe attempteduntil thebatteryhasstabilizedata temperaturebetween60 F (15.6C)and 100 F (37.8C). Stabilization shouldbeverifiedby3consecutivechecksof thebatteryorelectrolytetemperature,10minuteeapartandvaryingwithin~5 F(2.8C)of eachother,withinthe60 Fto100Frange. Finalcheckandadjustmentof theelectrolytelevelshouldthenbemade30minuteeafteranypreviousadditionsofdistilledwaterorelectrolyte.Theelectrolytefordrylead-acidbatteriesis