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ICS29.200
M41
YD
CommunicationsIndustryStandardofthePeople’
sRepublicofChina
YD/T731-2018
ReplaceYD/T731-2008
48VRectifierforTelecommunications
通信用48V整流器
(Englishtranslation)
Issuedate:2018-04-30Implementationdate:
2018-07-01
IssuedbytheMinistryofIndustryandInformationTechnologyofthePeople’sRepublicofChina
YD/T731-2018
Foreword
ChinaCommunicationsStandardsAssociation(CCSA)isinchargeofthisEnglish
translation.IncaseofanydoubtaboutthecontentsofEnglishtranslation,theChinese
originalshallbeconsideredauthoritative.
ThisstandardisdraftedinaccordancewiththerulesgiveninGB/T1.1-2009.
ThisstandardreplacesYD/T731-2008High-frequencySwitch-modeRectifierfor
Telecommunicationsinwhole.
ThefollowingtechnicaldeviationshavebeenmadewithrespecttotheYD/T731-2008:
a)Thestandardtitlehasbeenmodifiedto48VRectifierforTelecommunications;
b)TheDCoutputcurrentratingserieshavebeenmodified(see3.2,3.1inYD/T731-2008)
c)Therequirementsforwaveformdeviationofinputvoltagearedeleted,andthe
requirementthatTheinputvoltagewaveformdistortionshallnotbegreaterthan5%isadded
inthetestenvironmentalconditions(see5.1.1,4.2.5of2008Edition);
d)Thedefinitionofratedpowerisadded(see3.3);
e)Therequirementsforinputpowerfactoraremodified(see4.4,4.5of2008Edition);
f)Therequirementsforharmoniccomponentsofinputcurrentaremodified(see4.5,
4.6of2008Edition)
g)Therequirementsforrectifierefficiencyaremodified(see4.6,4.7of2008
Edition);
h)Therequirementsfordiscretefrequencynoisevoltagearedeleted(see4.8.3of2008
Edition);
i)Therequirementsforprotectionfunctionoffuse(orcircuitbreaker)aredeleted
(see4.23of2008Edition);
j)Therequirementsfordielectricstrengtharemodified(see4.24.2,4.26.2of2008
Edition)
k)Therequirementsforsoftstartaremodified(see4.15,4.16of2008Edition).
Attentionisdrawntothepossibilitythatsomeoftheelementsofthisstandardmay
bethesubjectofpatentrights.Theissuingbodyofthisdocumentshallnotbeheld
responsibleforidentifyinganyorallsuchpatentrights.
ThisstandardwasproposedandpreparedbyCCSA.
Thisstandardwasissuedin1994asfirstedition,wasfirstrevisedinFebruary2002
andthesecondrevisionwasissuedinJuly2008.Thisisthethirdrevisededition.
II
YD/T731-2018
1Scope
Thisstandardspecifiestheseries,requirements,testmethods,inspectionrules,sign,
packaging,transportandstorageof48Vrectifierfortelecommunications(hereinafter
referredtoastherectifier).
Thisstandardisapplicableto48Vrectifiersfortelecommunications,andmayalsobe
usedfor24Vrectifiers.
2NormativeReferences
Thefollowingreferenceddocumentsareindispensablefortheapplicationofthis
document.Fordatedreferences,onlytheeditioncitedapplies.Forundatedreferences,
thelatesteditionofthereferenceddocument(includinganyamendments)applies.
GB/T191Packaging-PictorialMarkingforHandlingofGoods
GB/T2423.1-2008EnvironmentalTestingforElectricandElectronicProducts-Part
2:TestMethods-TestA:Cold
GB/T2423.2-2008EnvironmentalTestingforElectricandElectronicProducts-Part
2:TestMethods–TestB:DryHeat
GB/T2423.3-2006EnvironmentalTestingforElectricandElectronicProducts-Part
2:TestMethods–TestCab:DampHeat,SteadyState
GB/T2423.5-1995EnvironmentalTestingforElectricandElectronicProducts-Part
2:TestMethods–TestEaandGuidance:Shock
GB/T2423.10-2008EnvironmentalTestingforElectricandElectronicProducts-Part
2:TestMethods–TestFc:Vibration(Sinusoidal)
GB/T2828.1-2012SamplingProceduresforInspectionbyAttributesPart1:Sampling
SchemesIndexedbyAcceptanceQualityLimit(AOL)forLot-by-lot
Inspection
GB/T2829-2002SamplingProceduresandTablesforPeriodicInspectionby
Attributes(ApplicabletoInspectionofProcessStability)
GB/T3859.2SemiconductorConverters-GeneralRequirementsandLine
CommutedConvertersPart1-2:ApplicationGuide
GB/T3873GeneralSpecificationsforProductsPackagingofCommunication
Equipment
GB4943.1-2011InformationTechnologyEquipment-Safety-Part1:General
Requirements
GB/T4980-2003DeterminationofSoundLevelforNoiseEmittedbyDisplacement
Compressors
GB/T18380.1-2001TestonElectricCablesunderFireConditions-Part1:Teston
1
YD/T731-2018
aSingleVerticalInsulatedWireorCable
YD/T122-1997NameplatesofProductsforPostandTelecommunicationsIndustry
YD/T282-2000GeneralReliabilityTestMethodforofCommunicationEquipment
YD/T944-2007TechnicalSpecificationandTestingMethodsforSurgeProtection
ofPowerSupplyforCommunications
YD/T983-2013LimitsandMethodsofMeasurementofElectromagnetic
CompatibilityofTelecommunicationPowerSupplyEquipment
3ProductSeries
3.1NominalvalueseriesofDCoutputvoltage
ThenominalvalueofDCoutputvoltageoftherectifieris48V.
Note:Productsotherthannominalvaluemaybeproducedaftertherequestoftheuser
andnegotiationwiththemanufacturer.
3.2RatedvalueseriesofDCoutputcurrent
TheratedvalueseriesofDCoutputcurrentoftherectifiermaybe10A,15A,30A,50A,
and100A.
Note:Productsotherthanratedvalueseriesmaybeproducedaftertherequestoftheuserand
negotiationwiththemanufacturer.
3.3Ratedpowerseries
Theoutputvoltageoftherectifieris57.6V.Theoutputpoweratratedcurrentisthe
ratedpoweroftherectifier.
4Requirements
4.1Environmentalconditions
4.1.1Temperaturerange
Operatingtemperaturerange:-5℃~+45℃.
Note:Theuppertemperaturelimitofspecialapplicationenvironmentis55℃.
Storageandtransporttemperaturerange:-40℃~+70℃.
4.1.2Relativehumidityrange
Operatingrelativehumidityrange:≤90%(40℃±2℃).
Storageandtransportrelativehumidityrange:≤95%(40℃±2℃).
4.1.3Atmosphericpressure
2
YD/T731-2018
Thealtitudeshallnotexceed1000m.Otherwise,thecapacityshallbereducedas
specifiedinGB/T3859.2.
4.1.4Impactandvibration
Therectifiershallbeabletowithstandtheimpactwithpeakaccelerationof150m/s2
anddurationof11ms.
Therectifiershallbeabletowithstandsinewavevibrationwithfrequencyof10Hz~55Hz
andamplitudeof0.35mm.
4.2ACinput
4.2.1Ratedvoltage
Singlephase:220V.
Threephases:380V.
4.2.2Ratedfrequency
Theratedfrequencyis50Hz.
4.2.3Voltagefluctuationrange
Whentherectifieroutputis100%ratedload,theACinputvoltageshallmeetthe
requirementsof85%~110%.
Note:WhentheACinputvoltageexceedstheaboverange,therectifiercanbederated.
4.2.4Frequencyfluctuationrange
Thefluctuationrangeofinputfrequencyis47.5Hz~52.5Hz.
4.3DCoutput
TheadjustablerangeofDCoutputvoltageis43.2V~57.6V.
TheDCoutputvoltagevalueofrectifiercanberegulatedmanuallyorunderthecontrol
ofmonitoringcircuit(systemmonitoringunit)continuouslywithintheadjustablerange.
TherectifiershalloutputratedcurrentwithintheadjustablerangeofDCoutput
voltage.
4.4Inputpowerfactor
TheinputpowerfactorofrectifiershallmeettherequirementsgiveninTable1.
Table1InputPowerFactor
ClassificationClassIClassIIClassIII
Inputpowerfactor(100%load)≥0.99≥0.96≥0.94
Inputpowerfactor(50%load)≥0.98≥0.95≥0.92
Inputpowerfactor(30%load)≥0.97≥0.94≥0.90
3
YD/T731-2018
4.5Totalharmoniccomponentofinputcurrent
Thetotalharmoniccomponentofinputcurrentofrectifiershallmeettherequirements
giveninTable2.
Table2TotalHarmonicComponentofInputCurrent(THDAfor3timesto39times)
ClassificationClassIClassIIClassIII
Totalharmoniccomponentofinputcurrent(100%≤5%≤10%≤25%
load)
Totalharmoniccomponentofinputcurrent(50%≤8%≤15%≤28%
load)
Totalharmoniccomponentofinputcurrent(30%≤12%≤20%≤30%
load)
Note:THDAistotalharmonicdistortionofcurrent
4.6Efficiency
TheefficiencyofrectifiershallmeettherequirementsgiveninTable3.
Table3Efficiency
Outputcurrent≥30A<30A
ClassificationClassIClassIIClassClassIClassIIClass
IIIIII
Efficiency(100%load)≥95%≥92%≥89%≥91%≥88%≥86%
Efficiency(50%load)≥96%≥92%≥89%≥92%≥88%≥86%
Efficiency(30%load)≥93%≥86%≥83%≥89%≥85%≥81%
4.7Noisevoltage
4.7.1Phonebalanceweightednoisevoltage
ThephonebalanceweightednoisevoltageattheDCoutputendoftherectifiershall
benotgreaterthan2mV.
4.7.2Broadbandnoisevoltage
ThebroadbandnoisevoltageattheDCoutputendofrectifierwithinthefrequencyband
of3.4kHz~150kHzshallbenotgreaterthan50mV.
ThebroadbandnoisevoltageattheDCoutputendofrectifierwithinthefrequencyband
of0.15MHz~30MHzshallbenotgreaterthan20mV.
4.7.3Peak-to-peakvaluenoisevoltage
Thepeak-to-peaknoisevoltageattheDCoutputendofrectifierwithinthefrequency
bandof0MHz~20MHzshallbenotgreaterthan200mV.
4
YD/T731-2018
4.8Loadeffect(loadregulation)
ThedifferencebetweentheDCoutputvoltageandtheoutputvoltagesettingvalueunder
differentloadconditionsshallnotexceed±0.5%oftheoutputvoltagesettingvalue.
4.9Sourceeffect(powergridregulation)
ThedifferencebetweentheDCoutputvoltageandtheoutputvoltagesettingvalueunder
differentACinputvoltagesshallnotexceed±0.1%oftheoutputvoltagesettingvalue.
4.10Stabilizedvoltageprecision
DifferentACinputvoltagesandloadsshallbecombined.Thedifferencebetweenthe
DCoutputvoltageandtheoutputvoltagesettingvalueundervariousconditionsshallnot
exceed±0.6%oftheoutputvoltagesettingvalue.
4.11Temperaturecoefficient(1/℃)
Relativeto20℃ambienttemperature,thedifferencebetweentheDCoutputvoltageand
theoutputvoltagesettingvalueshallnotexceed±0.02%oftheoutputvoltagesetting
valueeverytimethetemperaturechangesby1℃.
4.12Loadeffectrecoverytime(dynamicresponse)
TherecoverytimeafterthechangeofDCoutputvoltagecausedbythestepchange(sudden
change)oftheloadshallnotbegreaterthan200μs,anditsovershootshallnotexceed
±5%ofthesettingvalueofoutputvoltage.
Note:Therecoverytimereferstotheperiodoftimefromthetimewhenthechangeof
DCoutputvoltagerisestobegreaterthanthestabilizedvoltageprecision,tothetime
whenitrecoverstobelessthanorequaltoandnolongerexceedsthestabilizedvoltage
precision.
4.13Startup&shutdownovershootamplitude
ThemaximumpeakvalueofDCoutputvoltagechangecausedbystartup&shutdownshall
notexceed±5%ofthesettingvalueofDCoutputvoltage.
4.14Inrushstartingcurrent(surgecurrent)
Theinputimpulsecurrentcausedbystartingshallnotbegreaterthan150%ofthe
maximumsteady-stateinputcurrentpeakvalueundertheratedinputvoltage.
4.15Softstart
4.15.1Softstarttime
Thesoftstarttimeofrectifiershallbe3s~10s.
4.15.2Delaystarttimesettingfunction
5
YD/T731-2018
Therectifiershallhavethefunctionofsettingthedelaystarttime,whichcanbe
setremotelythroughthesystemmonitoringunitorthesystem.
4.16Acousticnoise
Theacousticnoiseshallnotbegreaterthan55dB(A-weighted).
4.17Telemetering,remotesignalingandremotecontrolfunctions
Therectifiershallhaveinterfacecircuit,whichcanbeconnectedwiththemonitoring
circuit(systemmonitoringunit),andshallhavethefollowingfunctionsunderthecontrol
ofthemonitoringcircuit(systemmonitoringunit):
-Telemetering:Rectifieroutputvoltageandrectifieroutputcurrent;
-Remotesignaling:Rectifierworkingstate(on/off,equalized/floatingcharging/test,
currentlimiting/non-currentlimiting,fault/normal)
-Remotecontrol:On/off,equalized/floatingcharging/test.
4.18DCoutputcurrentlimitingoroutputpowerlimitingperformance
TherectifiershallhaveDCoutputcurrentlimitingperformance.TheDCoutputcurrent
limitingprotectionfunctionoftherectifiercontainstwoforms:
-ThecurrentlimitvalueofDCoutputcurrentoftherectifiercanbebetween105%~110%
ofitsnominalvalue.Whentheoutputcurrentreachesthecurrentlimitvalue,therectifier
willoutputthecurrentlimitvalue;
-Forconstant-powerrectifier,whentheDCoutputpowerofrectifierreachesthe
constantpowervalue,therectifiershalloutputinpowerlimitingmode.Therectifiershall
alsohaveautomaticshort-circuitprotectionperformance.Afterthefaultiseliminated,
therectifiershallreturntoworkautomatically.
4.19Loadsharing(paralleloperation)performance
Therectifiershallbeabletoadoptmultiplerectifiersofthesamemodelforparallel
operation.Whentherectifierworksindependentlyoriscontrolledbythesystemmonitoring
unitduringparalleloperation,theloadshallbeshared.Theunbalancedvalueoftheshared
loadwithintherangeof50%~100%oftheratedoutputcurrentofthesinglemachineshall
notexceed±5%oftheratedvalueoftheDCoutputcurrent.
4.20ACinputovervoltage,undervoltageandopen-phaseprotectionfunction
Therectifiershallbeabletomonitorthechangeofgridvoltage.WhentheACinput
voltageistoohighortoolow,therectifiershallhavethefollowingprotectionfunctions:
-Whenthegridvoltageistoohigh,therectifiershallhavethefunctionofovervoltage
shutdownprotectionandgiveanalarm.Afterthegridvoltagereturnstonormal,itcan
automaticallyreturntowork.Thesettingofovervoltageprotectionvoltageshallnotbe
lowerthan115%oftheratedvoltage(thesingle-phasevoltageshallbenotlessthan253V,
andthree-phasevoltageshallbenotlessthan437V);
6
YD/T731-2018
-Whenthegridvoltageistoolow,therectifiershallhavethefunctionofundervoltage
protectionandgiveanalarm.Afterthegridvoltagereturnstonormal,itcanautomatically
returntowork.Thesettingofundervoltageprotectionvoltageshallnotbehigherthan
80%oftheratedvoltage(thesingle-phasevoltageshallbenotgreaterthan176V,and
three-phasevoltageshallbenotgreaterthan304V);
-Forthree-phaseinputrectifier,incaseofinputphaseloss,therectifiershallhave
openphaseprotectionfunctionandgiveanalarm.Afterthepowergridreturnstonormal,
itcanautomaticallyresumeoperation.
4.21Over-temperatureprotectionfunction
Whentheinternaltemperatureofrectifierreachestheprotectionsettingvalue,it
canautomaticallygiveanalarmandprotection.Afterthefaultiseliminated,therectifier
shallreturntoworkautomatically.
4.22Lightningprotectionperformance
TheACinputterminalofrectifiershallbeequippedwithsurgeprotectivedevice,which
shallcomplywiththerequirementsgiveninYD/T944.
4.23Groundingperformance
Theresistancebetweenallaccessiblemetalshellsandmetalpartsandtheprotective
earth(PE)terminalofrectifiershallnotbegreaterthan0.1Ω.
4.24Safetyrequirements
4.24.1Insulationresistance
WhenthetestvoltageisDC500V,theinsulationresistanceoftheACpartandDCpart
ofthemaincircuitofrectifiertothegroundandtheACparttotheDCpartshallnot
belessthan2MΩ.
4.24.2Dielectricstrength
TheACcircuittogroundcanwithstand50HzACvoltagewitheffectivevalueof1500V
(leakagecurrent≤30mA)or2120VDCvoltageequivalenttoitspeakvaluefor1minwithout
breakdownandflashover.
TheACcircuittoDCcircuitcanwithstand50HzACvoltagewitheffectivevalueof3000V
(leakagecurrent≤30mA)or4240VDCvoltageequivalenttoitspeakvaluefor1minwithout
breakdownandflashover.
TheDCcircuittogroundcanwithstand50HzACvoltagewitheffectivevalueof500V
(leakagecurrent≤30mA)or710VDCvoltageequivalenttoitspeakvaluefor1minwithout
breakdownandflashover.
4.24.3Touchcurrentandprotectiveconductorcurrent
7
YD/T731-2018
Thetouchcurrentbetweentheprotectiveearth(PE)ofrectifierandtheinputneutral
line(N)shallnotbegreaterthan3.5mA.
Note:Whenthetouchcurrentisgreaterthan3.5mA,theeffectivevalueoftheprotective
conductorcurrentshallnotexceed5%oftheinputcurrentofeachphase.Iftheloadis
unbalanced,themaximumvalueamongthreephasecurrentsshallbeusedforcalculation.
Thecrosssectionalareaoftheprotectiveconductoronthehigh-currentpathofthe
protectiveconductorshallnotbelessthan1.0mm2.Attheprimarypowerconnectionend
closetotherectifier,asignboardindicatingwarningwordsorsimilarwordsshallbe
arranged,thatis,“Hightouchcurrentmustbegroundedbeforeturningonthepowersupply”.
4.24.4Flame-retardantperformanceofmaterials
Theflame-retardantratingofPCBusedfortherectifiershallmeettheV-0requirements
asspecifiedinGB4943.1-2011.Theflame-retardantratingofplasticconductorshallmeet
therequirementsasspecifiedinGB/T18380.1-2001.Theflame-retardantratingofother
insulatingmaterialsshallmeettheV-1requirementsasspecifiedinGB4943.1-2011.
4.25Electromagneticcompatibility
4.25.1Conducteddisturbancelimit
TheconducteddisturbancelimitofrectifiershallcomplywiththerequirementsofClass
AgiveninTable1ofYD/T983-2013.Theconducteddisturbanceshallbemeasuredatthe
inputandoutputportsofthepowersupply.
Note:Theoutputportrefersto48Vforcommunication.
4.25.2Radiationdisturbancelimit
TheradiationdisturbancelimitofrectifiershallcomplywiththerequirementsofLevel
AinTable1ofYD/T983-2013.
4.25.3Harmoniccurrentlimit
Theharmoniccurrentlimitofrectifiershallcomplywiththelimitrequirementsof
Class-AequipmentgiveninTable1ofYD/T983-2013.
4.25.4Voltagefluctuationandflickerlimit
Thevoltagefluctuationandflickerlimitofrectifiershallcomplytherequirements
giveninTable1inYD/T983-2013.
4.25.5Immunity
4.25.5.1Electrostaticdischargeimmunity
Inthetelecommunicationcenterenvironment,therectifiershallmeettherequirements
giveninTable3inYD/T983-2013duringorafterthetest.
Innon-telecommunicationcenterenvironment,therectifiershallmeettherequirements
8
YD/T731-2018
giveninTable8inYD/T983-2013duringorafterthetest.
4.25.5.2Radiatedelectromagneticfieldimmunity
Inthetelecommunicationcenterenvironment,therectifiershallmeettherequirements
giveninTable3inYD/T983-2013duringorafterthetest.
Innon-telecommunicationcenterenvironment,therectifiershallmeettherequirements
giveninTable8inYD/T983-2013duringorafterthetest.
4.25.5.3Electricalfasttransientburstimmunity
Inthetelecommunicationcenterenvironment,therectifiershallmeettherequirements
giveninTable4,Table5,Table6andTable7inYD/T983-2013duringorafterthetest.
Innon-telecommunicationcenterenvironment,therectifiershallmeettherequirements
giveninTable9,Table10,Table11andTable12inYD/T983-2013duringorafterthetest.
4.25.5.4Surge(impact)immunity
Inthetelecommunicationcenterenvironment,therectifiershallmeettherequirements
giveninTable4,Table5andTable6inYD/T983-2013duringorafterthetest.
Innon-telecommunicationcenterenvironment,therectifiershallmeettherequirements
giveninTable9,Table10andTable11inYD/T983-2013duringorafterthetest.
4.25.5.5Immunitytoconducteddisturbanceinducedbyradiofrequencyfield
Inthetelecommunicationcenterenvironment,therectifiershallmeettherequirements
giveninTable4,Table5,Table6andTable7inYD/T983-2013duringorafterthetest
Innon-telecommunicationcenterenvironment,therectifiershallmeettherequirements
giveninTable9,Table10,Table11andTable12inYD/T983-2013duringorafterthetest.
4.25.5.6Voltagesagandvoltageshort-timeinterruptionimmunity
Inthetelecommunicationcenterenvironment,therectifiershallmeettherequirements
giveninTable6inYD/T983-2013duringorafterthetest.
Innon-telecommunicationcenterenvironment,therectifiershallmeettherequirements
giveninTable11inYD/T983-2013duringorafterthetest.
4.26Reliabilityindex
Meantimebetweenfailures(MTBF)is≥1×105h.
5TestMethods
5.1Preparationbeforetest
5.1.1Testenvironmentalconditions
9
YD/T731-2018
Beforepower-on,therectifierundertestshallbebalancedwiththeambienttemperature,
andpreheatedaccordingtothespecifiedpreheatingtimeoftheproduct.Theinputvoltage
waveformdistortionshallnotbegreaterthan5%.
Unlessotherwisespecified,thetestshallbeconductedunderstandardatmospheric
conditions.Thestandardatmosphericconditionsare:
-Ambienttemperature:15℃~35℃;
-Relativehumidity:45%~75%;
-Atmosphericpressure:86kPa~106kPa.
5.1.2Testinstrumentsandequipment
SeeAnnexA.
5.2ACinputtest
5.2.1Basicprincipleoftest
ThebasicprincipleofthetestisshowninFigure1.
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