XITRON XT2640 - Range of XT2640 Measurements for Compliance

XT2640OperatingManual 13July2016 Page90of187
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TheXT2640providesyouwithassistanceinchoosingtheclassificationofaEUTbygivingtherangeofWatts
measurementsencounteredduringtheassessment;thisalongwithotherdetailsavailabletoyouregardingtheEUTcan
thenbeusedtoallowyoutoselecttheclassificationtouse.
AccordingtoEN61000‐3‐2,ClassC(spcl)onlyappliestoaEUThavingaspecificcurrentwaveformwhichhasaspecific
shapeandhasaspecificphaserelationshiptothevoltagewaveform(seefigure2andclause7.3binEN61000‐3‐2).The
XT2640doesnotcheckthatthecurrentwaveformmeetsthisrequirementandsothisisyourresponsibility,itis
recommendedthatyoucapturethecurrentwaveforminsomefashionandcheckitsshapeandphaserelationshipand
reportthosefindingsinyourfinalassessmentreporttosupportselectingclassC(spcl).Ingeneral,selectionofclassC(spcl)
isnotrecommendedandselectionofclassC(tbl3)isrecommendedforsuchaEUTifpossible.
18.1.4.2 EN61000‐3‐12LIMITSTABLESELECTION
TheXT2640performsassessmentsaccordingtoEN61000‐3‐12usingthetables2,3,4and5asdefinedinthatstandard.Itisyour
responsibilitytochoosethetabletoapply.
Note:
TheXT2640providesyouwithassistanceinchoosingtheclassificationofaEUTbygivingtherangeofcurrent
measurementsencounteredduringtheassessmentforeachphasewhichthenallowsyoutodecideiftheEUTisa“balanced
load”.ThedefinitionofbalancedloadrequiresknowledgeofwhethertheEUTwasdesignedtohaveidenticalphase
loading,andifmeasurementsareusedthentheword“identical”isprobablytoonarrowasnotwomeasurementsareever
“identical”.
TheXT2640alsoprovidesyouwithassistanceinchoosingtables4and5astheserelyontheEUTmeetingcertain
conditionsduringassessment,entitled‘a’,‘b’,‘c’,‘d’,‘e’and‘f’inEN61000‐3‐12clause5.2,byreportingwhetherconditions
‘a’,‘c’,‘d’and/or‘f’aremet.TheXT2640cannotassistwithwhetherconditions‘b’or‘e’aremet(whichareactuallyboth
thesamecondition)asthesedependonknowledgewhichcannotbeobtainedfrommeasurementsbutaredependenton
“
thedesignofthepieceofequipment”.
TheXT2640alsoprovidesyouwithassistanceinchoosingwhichtabletousefora“hybrid”EUTbydetectingif
circumstance‘a’appliesasdefinedinEN610000‐3‐12clause5.2.TheXT2640cannotassistwithcircumstance‘b’for
“hybrid”equipmentasthatisdependenton“
theconstructionofhybridequipment”.
18.1.4.3 EN61000‐3‐12RSCEVALUESELE CTION
AssessmentofaEUTtoEN61000‐3‐12requiresareferencevalueentitled“Rsce”inEN61000‐3‐12.Foralltableselections,the
selectionofaRscevalueiscriticaltothepass/failresultoftheassessmentandEN61000‐3‐12containsthemethodsforyoutouseto
deriveitsvalueandalsotoensurethatthetestwiring,currentmeasurementresistance,andsupplysourceresistanceareapplicable
foragivenRscevalue.
Generally,aRscevalueof33maybeapplied(whichisthengenerallyacceptablefortheEUTtobeusedonallsupplies),butoftena
EUTwillnotmeetthisrequirementsoahigherRscemustbeselectedbyyouwhichallowstheEUTtomeettherequirementsbut
restrictsthefinaluseoftheEUTonlytocertainsupplies.
TheXT2640assistswiththisbyallowingyoutoeither‐
a)
ConfigureazerovalueforRsce,inthatcasetheXT2640automaticallyprovidesthelowestvalueforRsceforwhichthe
assessmentresultsinapassingstatusforallsupplyphases(ifpossible)
b)
ChangetheconfiguredRscevaluemanuallyandreassessthemeasurementswithoutactuallyrepeatingtheassessment
itself.
ReassessingthepreviousassessmentmeasurementsinthismannermaynotbedefinitiveasachangedRscevaluemayaffectthe
requirementsforsupplysourceandthewiringusedtoperformtheassessment,soitmaybenecessarytoactuallyrepeatthe
entireassessmenttoresolveafinalRscevaluewhichisacceptableiftheinitialassessmentwasrunwithwiringetc.assuminga
lowerRscevalue.
18.1.5 RANGE OFXT2640MEASUREMENTSFORCOMPLIANCE
ItisoftenacceptedwithoutquestionthatanEN61000‐4‐7Class1compliantmeasurementdevicesuchastheXT2640meetsthe
measurementrequirementsofEN61000‐3‐2and‐12.Thisisnotactuallythecaseinpractice;therepeatabilityandreproducibility
requirementscontainedinEN61000‐3‐2and‐12farexceedtheaccuracyrequirementsforaClass1devicedefinedbyEN61000‐4‐7,
andtheClass1accuracyrequirementinEN16000‐4‐7doesnotguaranteethatthemeasurementequipmentevenhassufficient
accuracytoassessaEUTtowithinthelimitsstatedinEN61000‐3‐2or‐12.
TherangeofmeasurementsspecifiedbelowfortheXT2640includetherequirementsforClass1ofEN61000‐4‐7,therepeatability
andreproducibilityrequirementsofEN61000‐3‐2,andtherepeatabilityrequirementsofEN61000‐3‐12,allwithaminimumofa4:1
marginwhichistheindustrynormformeasurementuncertainty,andarevalidthroughouttheoperatingenvironmentrange
specifiedinsection25.2ofthismanualwhentheXT2640isusingitsinternalcurrentshunts.Ifusingexternalcurrentshuntsthen
seesection18.1.5.1forfurtherdetails,dependingonthespecificationsoftheexternalcurrentdevicetherangeofcurrents,power
andpowerfactorspecifiedmaybedifferentwhenusingexternalcurrentdevices.
WhenconfiguredforEN61000‐3‐2or‐12measurements,theXT2640isguaranteedtoexceedtherequirementsoftheabovelisted
standardswithinthefollowingrangesofmeasurements(thisspecificationreplacesallotherrelevantaccuracyspecifications
containedinsection26ofthismanualforassessmentresultspurposesonly)‐
Frequency:Anyfrequencyintherange45‐54Hzor56‐65Hz(assessmentusingfrequenciesintherange54‐56Hzispossible
butnotrecommended).
Voltage:Anyphasevoltageinthefollowingrangeforeachchanneltype(thecurrentoptiondoesnotaffecttheranges
allowed)‐
AorSchanneltype:75‐700Vrms.