FLUKE双显示多用表上课讲义

1、Good is good, but better carries it.精益求精，善益求善。FLUKE双显示多用表-FLUKE45双显示多用表FLUKE45是具有五位数字显示的四位半数字式多用表。可用于测量直流电压、交流电压、直流电流、交流电流、电阻、频率、两个端点之间的通断及二极管测试。测量范围可手动选择，也可自动选择。可测量输入量的绝对数值，也可测量输入量之间的相对值。可选择21种参考阻抗做功率测量，阻抗由2到8000，测量结果显示为dBm值(毫瓦分贝值，dBm=10log10(1000value2/referenceimpedance，其中value为测量到的rms电压值，单位为V)。利

2、用其“保持”功能还可测量输入的最大值、最小值。可同时测量两个量，例如：交流电压的电压值及其频率；元件两端的电压降以及流过该元件的电流；输入电压中交流分量的rms电压值和直流分量电压值；等等。有三种测量速度供选择：慢、中等、快。相对地，测量速度慢，则测量精度高；测量速度快，则测量精度低。上述功能是通过人在仪器的正面面板上操作来实现的，称其为手工操作使用。在仪器的背面面板上还有RS-232接口和GPIB/IEEE-488接口。将这些接口与PC机相连，可选用QuickStart45软件包，实现FLUKE45与PC机之间的快速设置和通讯，可方便地编制、存储和调用使用者自定义的测量程序。从而实现对该仪器

3、的遥控使用。FLUKE45可选择交流供电和直流电池供电。所以，它既可以在实验室使用，也可以在室外使用。直流供电电压为8V。要真正使用好一台仪器，必须阅读该仪器的说明书，并在使用过程中反复查阅。与过去的多用表相比，FLUK45是一个较复杂的仪器。特别是对该仪器的遥控使用，它要求使用者具有关于计算机方面的知识。由于本实验教材篇幅有限，这里只对手工操作使用做简介。了解该仪器的性能指标对于正确使用该仪器、以及分析测量结果的精度是十分重要的。直接阅读原版用户手册，比阅读翻译后的用户手册更有利于了解关于本仪器的具体性能指标和基本操作使用方法。所以直接从“FLUKE45DualDisplayMultimet

4、er,UsersManual”摘录了以下内容，其中包含该仪器的性能指标和手工操作使用该仪器的基本操作方法。建议在使用本仪器之前，使用者必须阅读以下的内容。这些内容是手工操作使用该仪器所必须知道的内容。SpecificationsThefollowingspecificationsareundertheassumeofA1-yearcalibrationcycleAnoperatingtemperatureof18to28CRelativehumiditynotexceeding90%(non-condensing)(70%for1,000krangeandabove)Accuracyisexp

5、ressedaspercentageofreading+digits.DISPLAYCOUNTSREADINGRATESRateReadingperSecondFullRangeDisplayCountsSlowMediumFast2.552099,99930,0003,000*Ohmsfullrangewilltypicallybe98,000countsRS-232ANDIEEE-488READINGTRANSFERRATESRateReadingPerSecondInternalTriggerOperation(TRIGGER1)InternalTriggerOperation(TRIG

6、GER4)PrintModeOperation(Printsetat1)SlowMediumFast2.55.013.5TYPICALSINGLEMEASUREMENTRESPONSETIME(InSecond)SlowRateMediumRateFastRateMeas.FunctionAutoRange*SingleRange*AutoRange*SingleRange*AutoRange*SingleRange*V=VA=ADiodeFreq.*1.002.200.600.601.400.501.200.600.800.500.500/600.500.

7、500.802.000.400.401.200.301.200.400.600.300.300.400.300.500.301.000.200.500.400.100.700.100.300.100.300*Timetoauto-rangeanewmeasurementfromthelowesttothehighestrangeandtodisplaytheresult.*Typicaltimetochangetothenexthigherorlowerrangeanddisplaytheresult.*Frequencygreaterthan150Hz.Refertof

8、requencymeasurementrats.DCVOLTGERangeResolutionAccuracySlowMediumFast(6Months)(1Year)300mV3V30V300V1000V10V100V1mV10mV100mV100V1mV10mV100mV1V0.02%+20.02%+20.02%+20.02%+20.02%+20.025%+20.025%+20.025%+20.025%+20.025%+2100mV1000mV10V100V1000V1V10V100V1mV10mV0.02%+60.02%+60.02%+60.02%+60.02%+60.025%+60.

9、025%+60.025%+60.025%+60.025%+6InputImpedance10Minparallelwith80dBat50or60Hz,slowandmediumrats.54dBforfrequenciesbetween50-440Hz,slowandmediumrates.60dBat50Hz,fastrate(Note:Fastratehasnofiltering).MaximumAllowableACVoltageWhileMeasuringDCVoltageor(AC+DC)VoltageRangeMaxAllowablePeakACVoltagePeakNormal

10、ModeSignalNMRR*80dB*NMRR60dB*300mV3V30V300V1000V100mV1000mV10V100V1000V15V15V1000V1000V1000V15V15V50V50V200V15V15V300V300V1000V*NMRRisNormalModeRejectionRatio.*NormalModeRejectionRatioat50or60Hz0.1%.CommonModeRejectionRatio90dBatDC,50or60Hz,(1kUnbalanced,mediumandslowrates).MaximumInput1000VDCorpeak

11、Aconanyrange.TRUERMSACVOLTAGE,AC-COUPLEDRangeResolutionSlowMediumFast300mV3V30V300V750V100mV1000mV10V100V1000V1V10V100V1mV10mV10V100V1mV10mV100mV100V1mV10mV100mV1VAccuracyFrequencyLinearAccuracyDBAccuracyPower*MaxInputatUpperFreqSlowMediumFastSlow/Med.Fast20-50Hz50-10kHz10-20kHz20-50kHz50-100kHz1%+1

12、000.2%+1000.5%+1002%+2005%+5001%+100.2%+100.5%+102%+205%+507%+20.5%+20.5%+22%+35%+60.150.080.110.290.700.740.782%+100.4%+101%+104%+2010%+50750V750V750V400V200V*Errorinpowermodewillnotexceedtwicethelinearaccuracyspecification.Accuracyspecificationsapplywithinthefollowinglimits,basedonread

13、ingrate:SlowReadingRat:Between15,000and99,999counts(fullrange).MediumReadingRate:Between1,500and30,000counts(fullrange).FastReadingRate:Between150and3,000counts(fullrange).DecibelResolutionResolutionSlow&MediumFast0.01dB0.1dBDECIBELREFERENCERESISTANCE80003009312002507510001505090013516*8001258*600*1

14、244*5001102*Defaultresistance*ReadingdisplayedinWatts(power).InputImpedance1Minparallelwith60dBat50or60Hz(1kunbalancedmediumrate).MaximumInput750Vrms,1000Vpeak2107Volt-Hertzproductonanyrange,normalmodeinput.1106Volt-Hertzproductonanyrange,normalmodeinput.(AC+DC)VoltageAccuracyTotalMeasurementErrorwi

15、llnotexceedthesumoftheseparateACandDCaccuracyspecifications,plus1displaycount.Refertotableunder“MaximumAllowableACVoltagewhileMeasuringDCVoltageor(AC+DC)Voltages”.NOTE:WhenmeasuringAC+DC,(oranydualdisplaycombinationofACandDC)inthefastreadingrate,theFluke45mayshowsignificanterrors.Thisresultsfromalac

16、koffilteringontheDCportionofthemeasurementforthefastreadingrate.Toavoidthisproblem,useonlythe“slow”and“medium”readingratesforAC+DCorACandDCcombination.MaximumFrequencyofACVoltageInputWhileMeasuringACCurrentWhenthemetermakesACcurrentandACvoltagemeasurementsusingthedualdisplay,themaximumfrequencyofthe

17、voltageinputislimitedtothemaximumfrequencyofthecurrentfunction.Forexample,ifyouaremakinganACcurrentmeasurementonthe10Arange,themaximumfrequencyofthevoltageinputmustbelessthan2kHz.DCCURRENTRangeResolutionAccuracyBurdenVoltage*SlowMediumFast30mA100mA10A10mA100mA10A100nA1A100A1A10A1mA10A100A10mA0.05%+3

18、0.05+20.2+50.05%+150.05%+50.2%+70.45V1.4V0.25V0.14V1.4V0.25V*Typicalatfullrange.MaximumInputTobeusedinprotected,lowenergycircuitsonly,nottoexceed250Vor4800Volt-Amps(IEC664InstallationCategoryII.)mA:300mADCorACrms.Protectedwitha500mA,250V,IEC127-sheetI,fastblowfuse.A:10ADcorACrmscontinuous,or20ADCorA

19、Crmsfor30secondmaximum.Protectedwitha15A,250V,10,000Ainterruptrating,fastblowfuse.NOTE:ResistancebetweentheCOMbindingpostandthemetersinternalmeasuringcircuitisapproximately.003.ACCURRENTRangeResolutionBurdenVoltage*SlowMediumFast10mA30mA100mA10A100nA1A100A1A10A1mA10A100A10mA0.14V0.45V1.4V0.25V*Typic

20、alatfullrange.AccuracyRangeFrequencyAccuracySlowMediumFastmA(To100mA)mA(To100mA)mA(To100mA)A(1-10A)A(1-10A)A(0.5to1A)A(0.5to1A)20-50Hz50Hz-10kHz10-20kHz20-50kHz50Hz-2kHz20-50Hz50Hz-2kHz2%+1000.5%+1002%+2002%+1001%+1002%+3001%+3002%+100.5%+102%+202%+101%+102%+301%+307%+20.8%+22%+37%+21.3%+27%+41.3%+4

21、mAaccuracyspecificationsapplywithinthefollowinglimits,basedonreadingrate:SlowReadingRat:Between15,000and99,999counts(fullrange).MediumReadingRate:Between1,500and30,000counts(fullrange).FastReadingRate:Between150and3,000counts(fullrange).MaximumCrestFactor3.0MaximumInputTobeusedinprotected,lowenergyc

22、ircuitsonly,nottoexceed250Vor4800Volt-Amps(IEC664InstallationCategoryII.)mA:300mADCorACrms.Protectedwitha500mA,250V,IEC127-sheetI,fastblowfuse.A:10ADcorACrmscontinuous,or20ADCorACrmsfor30secondmaximum.Protectedwitha15A,250V,10,000Ainterruptrating,fastblowfuse.NOTE:ResistancebetweentheCOMbindingposta

23、ndthemetersinternalmeasuringcircuitisapproximately.003.OHMSRangeResolutionAccuracyTypicalFullScaleVoltageMaxCurrentThroughtheUnknownSlowMediumFast3003k39k300k3M30M300M*100100010k100k1000k10M100M*1m10m100m110100100k10m100m1101001000100k100m1101001k10k1M0.05%+2+0.020.05%+20.05%+20.05%+20.06%+20.25%+22

24、%0.05%+8+0.020.05%+8+0.020.05%+80.05%+80.06%+80.25%+62%+90.20.051mA120A14A1.5A150A320A320A1mA120A14A1.5A150A320A320A*Becauseofthemethodusedtomeasureresistance,the100M(slow)and300M(mediumandfast)rangecannotmeasurebelow3.2Mand20M,respectively.“UL”(underloa

25、d)isshownonthedisplayforresistancebelowthesenormalpoints,andthecomputerinterfaceoutput“+1E-9”.OpenCircuitVoltage3.2voltsmaximumonthe100,300,30M,100M,and300Mrange,1.5voltsmaximumonallotherranges.InputProtection500VDCorrmsAConallrangesDIODETEST/CONTINUITYMaximumReadingResolutionSlowMediumFast999.99mV2

26、.5V2.5V10V100V1mVTestCurrentApproximately0.7mAwhenmeasuringaforwardbiasedjunctionAudibleToneContinuoustoneforcontinuity.Brieftonefornormalforwardbiaseddiodeorsemiconductorjunction.OpenCircuitVoltage3.2voltsmaximumContinuityCaptureTime50smaximum,10stypicalInputProtection500voltsDCorrmsACNOTE:Whenthem

27、eterissettomeasurefrequencyandthereisnoinputsignal(I.e.,inputterminalsareopen),themetermayreadapproximately25kHz(ratherthantheexpectedzero).Thisisduetointernalcapacitivepickupoftheinverterpowersupplyintothehigh-impedance,inputcircuitry.Withsourceimpedanceof1MHzApplicableFunctionsVoltsACandCurrentACR

28、angeResolutionAccuracySlow&mediumFast1000Hz10kHz100kHz1000kHz1MHz*0.01Hz0.1Hz1Hz10Hz100Hz0.1Hz1Hz10Hz100Hz1kHz05%+20.05%+10.05%+10.05%+1NotSpecified*Specifiedto1MHz,butwillmeasureabove1MHz.SensitivityofACVoltageFrequencyLevel(sineWave)5Hz-100kHz100kHz-300kHz300kHz-1MHzAbove1MHz30mVrms100mVrms1VrmsNo

29、tSpecifiedSensitivityLevelofACCurrentFrequencyInputLevel5Hz-20kHz45Hz-2kHz100mA10A3mArms3mArmsNOTE:Whenthemeterissettomeasurefrequencyandthereisnoinputsignal(I.e.,inputterminalsareopen),themetermayreadapproximately25kHz(ratherthantheexpectedzero).Thisisduetointernalcapacitivepickupoftheinverterpower

30、supplyintothehigh-impedance,inputcircuitry.Withsourceimpedanceof2k,thispickupwillnotaffecttheaccuracyorstabilityofthefrequencyreading.QUICKREFERENCEGUIDEOFOPERATINGFLUKE45FrontPanelofFLUKE45RearPanelofFLUKE45AGUIDETOBASICFRONTPANELOPERATIONOPERATIONHOWTOPERFORMCOMMENTSSelectMeasu.functionPresswhiteb

31、utton.AnnunciatorindicatesSelectedfunctionIfsecondarydisplayison,pressingafunctionbuttonturnssecondarydisplayoff.DualDisplaySelectanymeasurementfunctionormodifierfortheprimarydisplay,press“2ND”,thenpressafunctionbuttontoselectafunctionforsecondarydisplay.Pressanyfunctionbuttontoturnoffsecondarydispl

32、ayandselectthatfunctiononprimarydisplay.Functionmodifiersandmanualrangemodecannotbeselectedinsecondarydisplay.RefertotheTable4-1forsuggestedapplicationsofdualdisplay.Or,press“2ND”twicetoturnoffsecondarydisplaywithoutaffectingprimarydisplay.SelectManu.orautorangeUprangeDownrangePress“AUTO”totogglebet

33、weenmanualandautorangemode.Press“UP”.Press“DOWN”.“AUTO”displayinautomodenotdisplayinmanualmode.Manualrangecannotbeselectedinsecondarydisplay.ChangeMeasu.RatPress“RATE”tostepthrough“S”(Slow,2.5readings/sec)“M”(Medium,5readings/sec)“F”(Fast,20readings/sec)Rateaffectsresolutionasfollows:“S”=100,000coun

34、ts.“M”=30,000counts.“F”=3,000counts.Selectedreadingrateappliestoallmeasurementexceptfrequency.RELmodifierPress“REL”toenterandexitrelativemodifierInREL,readingsarerelativetoa“base”valueshownonthedisplaybeforeRELselected.InREL,themanualrangemodeisselectedandtherangeissettopresentrange.“REL”displayed.R

35、elativemodifiercanbeselectedonlyintheprimarydisplay.Tochangethisrelativebase,referto“UsingtheNumberEditor”inSection3.MNMXModifierPress“MNMX”toselect;presstotogglebetweenminimumandmaximumvalue;pressandholdfor2secondstoexit.MinimumandmaximumvaluesreadsinceMNMXselectedarestored.MNMXcanbeselectedonlyint

36、heprimarydisplay.InMNMX,manualrangeisselected,andtherangesettopresentrange.“MN”or“MX”shownondisplay.ConverttodBSetdBReferenceResistancePress“dB”buttontoenterandexitthedecibelsmodifier.Press“2ND”,thenpress“dB”.Press“UP”or“DOWN”toscrolltovalue(2to8000).Press“AUTO”toselect.dBcanselectedonlywhenavoltage

37、functionisselectedontheprimarydisplay.dBToabort,pressanybuttonbut“AUTO”,“UP”,or“DOWN”.SelectaudioPowerSetdBreferenceresistanceto2,4,8,or16.Press“dB”twice.“POWER”willbeshowninsecondarydisplay.Press“dB”oranybuttontoexitaudiopower.HolddisplayReadingTouchHoldPress“HOLD”toenteTouchHold.Pressagaintoupdatereading.Press“HOLD”for2secondstoexit.INTouchHold,me