电类专业英语教学课件word作者汪建宇17课资料

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InstallingtheS7-200S7_200的安装TheS7-200equipmentisdesignedtobeeasytoinstall.Youcanusethemountingholestoattachthemodulestoapanel,oryoucanusethebuilt-inclipstomountthemodulesontoastandard(DIN)rail.ThesmallsizeoftheS7-200allowsyoutomakeefficientuseofspace.S7_200设备是易于安装,可以通过安装孔固定到板上,或者可以通过固定夹安装到标准定位上.因为S7_200的面积很小,所以你可以充分利用空间.1.GuidelinesforInstallingS7-200DevicesYoucaninstallanS7-200eitheronapaneloronastandardrail,andyoucanorienttheS7-200eitherhorizontallyorvertically.1.S7_200安装方法你可以把S7_200安装到板上或安装到标准的栏位上,同时你可以把它放成水平或坚直的.1)SeparatetheS7-200DevicesfromHeat,HighVoltage,andElectricalNoiseAsageneralruleforlayingoutthedevicesofyoursystem,alwaysseparatethedevicesthatgeneratehighvoltageandhighelectricalnoisefromthelow-voltage,logic-typedevicessuchastheS7-200.把S7_200远离热源、高压、电磁噪声通常，在安排系统部件布局时，要把高压与高电磁噪声部分与低电压与逻辑电路部分（如S7_200）分开来放置WhenconfiguringthelayoutoftheS7-200insideyourpanel,considertheheat-generatingdevicesandlocatetheelectronic-typedevicesinthecoolerareasofyourcabinet.Operatinganyelectronicdeviceinahigh-temperatureenvironmentwillreducethetimetofailure.当把S7_200放置到板上时,要考虑发热的器件与把电磁器件定位到你系统盒里的闲置区中.在高温的环境下操作任何的电子器件都会让器件缩短寿命.Consideralsotheroutingofthewiringforthedevicesinthepanel.AvoidplacinglowvoltagesignalwiresandcommunicationscablesinthesametraywithACpowerwiringandhigh-energy,rapidly-switchedDCwiring.同样要考虑设备的在板上的布线情况,避免低压的信号线和通信信号线与高压的交流电和高能量.快速的DC切换线走同一个方向2)ProvideAdequateClearanceforCoolingandWiringS7-200devicesaredesignedfornaturalconvectioncooling.Forpropercooling,youmustprovideaclearanceofatleast25mmaboveandbelowthedevices.Also,allowatleast75mmofdepth.为降温与配线提供足够的间隙S7_200 针对自然对流冷却而设计.为了得到足够的降温效果,就要在这个器件的的上方和下方留有最少25mm的间距.同时,要有75mm的深度.Tip:Forverticalmounting,themaximumallowableambienttemperatureisreducedby10°C.MounttheS7-200CPUbelowanyexpansionmodules.提示:针对坚直安装时,最大的周围环境温度要比允许的最大的温度缩小10度.可以在任何的彭胀参数下安装的S7-200CPU.WhenplanningyourlayoutfortheS7-200system,allowenoughclearanceforthewiringandcommunicationscableconnections.ForadditionalflexibilityinconfiguringthelayoutoftheS7-200system,usetheI/Oexpansioncable.考虑S7_200系统的布局时,线间和通信线间要求有足够的间隙.使用IO扩展线,能更灵活配置S7_200系统,Figure1MountingMethods,Orientation,andClearance图一.安装方法,定位,与间隙2.PowerBudget2.电源设计AllS7-200CPUshaveaninternalpowersupplythatprovidespowerfortheCPU,theexpansionmodules,andother24VDCuserpowerrequirements.所有的S7_200处理器都有一个内部电源为cpu供电,可满足扩展模块和要求24V直流电源供电的模块TheS7-200CPUprovidesthe5VDClogicpowerneededforanyexpansioninyoursystem.PaycarefulattentiontoyoursystemconfigurationtoensurethatyourCPUcansupplythe5Vpowerrequiredbyyourselectedexpansionmodules.IfyourconfigurationrequiresmorepowerthantheCPUcansupply,youmustremoveamoduleorselectaCPUwithmorepowercapability.RefertoAppendixAforinformationaboutthe5VDClogicbudgetsuppliedbyyourS7-200CPUandthe5VDCpowerrequirementsoftheexpansionmodules.UseAppendixBasaguidefordetermininghowmuchpower(orcurrent)theCPUcanprovideforyourconfiguration.s7_200CPU提供了5V的逻辑直流电源支持扩展模块系统.注意你的系统配置,以保证你的CPU所提供5V直流电源使所选的扩展模块正常工作.如果你的CPU提供的电源不能满足的你配置所需的电源,你必须删除某个模块或选择另一个CPU以保证正常工作.附录A中有关于由S7_200CPU提供的电源和外部扩展模块要求的5V的信息.而附录B指导如何决定的你的CPU能够为配置提供多少电源.AllS7-200CPUsalsoprovidea24VDCsensorsupplythatcansupply24VDCforinputpoints,forrelaycoilpowerontheexpansionmodules,orforotherrequirements.Ifyourpowerrequirementsexceedthebudgetofthesensorsupply,thenyoumustaddanexternal24VDCpowersupplytoyoursystem.RefertoAppendixAforthe24VDCsensorsupplypowerbudgetforyourparticularS7-200CPU.所有的S7_200CPU都提供了24的传感器直流电压,这样可以保证24V的输入,和扩展模块继电器或其它的模块的电压需要.如果电源的需求量大于传感器电压,那样你就要增加一个外部的24V的直源来保证你系统工作.附录A给出了针对S7_200CPU24V传感器直流电源预算.Ifyourequireanexternal24VDCpowersupply,ensurethatthepowersupplyisnotconnectedinparallelwiththesensorsupplyoftheS7-200CPU.Forimprovedelectricalnoiseprotection,itisrecommendedthatthecommons(M)ofthedifferentpowersuppliesbeconnected.如果你需要一个外部的24V直流电,要保证它和S7_200CPU提供的传感器电源连接不是平行的.为了减少电流躁声的干拢,建议要把不同的电源的公共端(地)连起来.Warning:Connectinganexternal24VDCpowersupplyinparallelwiththeS7-20024VDCsensorsupplycanresultinaconflictbetweenthetwosuppliesaseachseekstoestablishitsownpreferredoutputvoltagelevel.警告:外部24VDC电源与S7_200专感器电源的平行连接会导致这两个电源之间冲突,这种冲突表现为两电源会寻找各自的输出参考输出电压.Theresultofthisconflictcanbeshortenedlifetimeorimmediatefailureofoneorbothpowersupplies,withconsequentunpredictableoperationofthePLCsystem.Unpredictableoperationcouldresultindeathorseriousinjurytopersonnel,and/ordamagetoequipment.在接下来的未知的操作中,这种冲突可能会导致这两个或者其中一个电源的寿命缩短,同样,有可能会让他们或其中一个不能工作.而未知的操作可能会导致生命安全受威胁,或受伤害,又或对仪器产生损害.TheS7-200DCsensorsupplyandanyexternalpowersupplyshouldprovidepowertodifferentpoints.S7_200直流电或外部24V电源提供的电源要接到不同的地方.3.InstallingandRemovingtheS7-200Modules安装和载剪S7_200的模块TheS7-200canbeeasilyinstalledonastandardDINrailoronapanel.S7_200可以简单的安装到标准的的DIN位上,或安装到板上.1)PrerequisitesBeforeyouinstallorremoveanyelectricaldevice,ensurethatthepowertothatequipmenthasbeenturnedoff.Also,ensurethatthepowertoanyrelatedequipmenthasbeenturnedoff.前提条件安装或移去S_200的某个电子器件时,要让断开电源.同样,要让继电器的电源断开.WarningAttemptstoinstallorremoveS7-200orrelatedequipmentwiththepowerappliedcouldcauseelectricshockorfaultyoperationofequipment.警告:利用提供的电源,在安装或移去S7_200模块或联接设备时可能会导致电震或对设备不良的误操作.FailuretodisableallpowertotheS7-200andrelatedequipmentduringinstallationorremovalprocedurescouldresultindeathorseriousinjurytopersonnel,and/ordamagetoequipment.AlwaysfollowappropriatesafetyprecautionsandensurethatpowertotheS7-200isdisabledbeforeattemptingtoinstallorremoveS7-200CPUsorrelatedequipment.在安装或减少模块时,没有关掉所有提供给S7_200电源来连接设备可能会导致死亡或人体伤害,,又或会损害仪器.通常,遵循正确的安全防范规则,以保证S7-200的电源断掉,才能进行安装和折去S7_200CPU或联接设备.AlwaysensurethatwheneveryoureplaceorinstallanS7-200deviceyouusethecorrectmoduleorequivalentdevice.在任何时候要保证:在更换或安装S7_200设备时,你要用正确的模块或者是可替代的器件Warning警告Ifyouinstallanincorrectmodule,theprogramintheS7-200couldfunctionunpredictably.如果你安装了不正确的模块,在S7_200的程序可能不能按预期那样运行.FailuretoreplaceanS7-200devicewiththesamemodel,orientation,orordercouldresultindeathorseriousinjurytopersonnel,and/ordamagetoequipment.用同样的模型,定位,或顺序来替换S7_200的器件将会失败,且会导致死亡会人体受伤害,或对设备产生破坏.ReplaceanS7-200devicewiththesamemodel,andbesuretoorientandpositionitcorrectly.利用同样的模型来替换S7_200的器件时要保证定位和放置正确.MountingDimensions安装尺寸TheS7-200CPUsandexpansionmodulesincludemountingholestofacilitateinstallationonpanels.RefertoTable1forthemountingdimensions.S7_200的CPU和扩展模块包含了安装孔到板上的简易安装尺寸.表1是安装尺寸说明Table1MountingDimensionsInstallingaCPUorExpansionModule安装CPU或扩展模块InstallingtheS7-200iseasy!Justfollowthesesteps.安装S7_200是很容易的,安装步骤如下:PanelMounting:板上装配:Locate,drill,andtapthemountingholes(M4orAmericanStandardnumber8),usingthedimensionsinTable1.定位,钻孔,在安装孔上攻螺纹(M4或美国标准的8号大小),参照表1的尺寸.Securethemodule(s)tothepanel,usingtheappropriatescrews.用合适的螺丝钉让模块固定到板上Ifyouareusinganexpansionmodule,connecttheexpansionmoduleribboncableintotheexpansionportconnectorundertheaccessdoor.如果使用了扩展模块,就要通过入孔门把扩展模块的电线连到扩展端口.DINRailMounting:DIN位的安装Securetherailtothemountingpanelevery75mm.每隔7.5mm把杆固定到安装板上.SnapopentheDINclip(locatedonthebottomofthemodule)andhookthebackofthemoduleontotheDINrail.咬开DIN夹(定位在模块的底部)然后把模块的底部钩到DIN杆上.Ifyouareusinganexpansionmodule,connecttheexpansionmoduleribboncableintotheexpansionportconnectorundertheaccessdoor.如果你使用了扩展模块,就要通过入孔门把扩展模块的电线连到扩展端口.RotatethemoduledowntotheDINrailandsnaptheclipclosed.Carefullycheckthatthecliphasfastenedthemodulesecurelyontotherail.Toavoiddamagetothemodule,pressonthetabofthemountingholeinsteadofpressingdirectlyonthefrontofthemodule.旋转模块到DIN杆上并用夹子咬紧.仔细检查夹子是不是已经夹稳安装杆,为了避免对模块的损坏,要按住安装而不是直接按在模块的前面部分.Tip：提示:UsingDINrailstopscouldbehelpfulifyourS7-200isinanenvironmentwithhighvibrationpotentialoriftheS7-200hasbeeninstalledvertically.如果S7_200是处于非常振动环境或是已经垂直安装了,这时,用DIN杆来安装是很好的选择.Ifyoursystemisinahigh-vibrationenvironment,thenpanel-mountingtheS7-200willprovideagreaterlevelofvibrationprotection.如果系统是处于高振动的环境,那么,板上安装S7_200将会给系统很好的防震保护.RemovingaCPUorExpansionModule移去CPU或扩展模块ToremoveanS7-200CPUorexpansionmodule,followthesesteps:移去S7_200的CPU或扩展模块,参考如下步骤:RemovepowerfromtheS7-200.去掉S7_200的电源Disconnectallthewiringandcablingthatisattachedtothemodule.MostS7-200CPUandexpansionmoduleshaveremovableconnectorstomakethisjobeasier.断掉连接扩展模块的线路,大多数的S7_200的CPU和扩展模块都有可折除的接口,这样拆除就很容易了.Ifyouhaveexpansionmodulesconnectedtotheunitthatyouareremoving,opentheaccesscoverdooranddisconnecttheexpansionmoduleribboncablefromtheadjacentmodules.如果你的扩展模块连到你要拆除的单元,那样你就打开孔盖来去掉连接.UnscrewthemountingscrewsorsnapopentheDINclip.拧开螺丝,或松开DIN夹.⑤Removethemodule.移去模块RemovingandReinstallingtheTerminalBlockConnector移去并重装终端模块的连接口MostS7-200moduleshaveremovableconnectorstomakeinstallingandreplacingthemoduleeasy.RefertoAppendixAtodeterminewhetheryourS7-200modulehasremovableconnectors.Youcanorderanoptionalfan-outconnectorformodulesthatdonothaveremovableconnectors.大部分的S7_200的模块拥有灵活的接口,以致于在安装和替换更容易.参照附录A你可以选择S7_200模块是否有灵活的接口.你可以订制输出口没有灵活接口的模块.ToRemovetheConnector:去除连接接口Opentheconnectordoortogainaccesstotheconnector.找连接门来找到连接口Insertasmallscrewdriverinthenotchinthemiddleoftheconnector.插入小螺丝起子到连接口的中间凹处.RemovetheterminalconnectorbypryingthescrewdriverawayfromtheS7-200housing.SeeFigure2.通过螺丝起子把终端接口从S7_200箱子中去除.看图2Figure2RemovingtheConnectorToReinstalltheConnector:重新安装连接口Opentheconnectordoor.打开连接门Aligntheconnectorwiththepinsontheunitandalignthewiringedgeoftheconnectorinsidetherimoftheconnectorbase.利用模块的连接脚把连接口对齐好,同时对齐好处于连接基板边缘内部的接口的布线边缘问题.③Pressdownfirmlytorotatetheconnectoruntilitsnapsintoplace.Checkcarefullytoensurethattheconnectorisproperlyalignedandfullyengaged.用力地向下压来旋转连接口直到放好为好止仔细检查以确保连接是正确地接上.4.GuidelinesforGroundingandWiring地线与布线规则PropergroundingandwiringofallelectricalequipmentisimportanttohelpensuretheoptimumoperationofyoursystemandtoprovideadditionalelectricalnoiseprotectionforyourapplicationandtheS7-200.电子设备合理布置地线和其它信号线可以是对系统正常运行的有利的,同时减少了噪声的干扰.Prerequisites前提条件Beforeyougroundorinstallwiringtoanyelectricaldevice,ensurethatthepowertothatequipmenthasbeenturnedoff.Also,ensurethatthepowertoanyrelatedequipmenthasbeenturnedoff.在进行走地线或装线到任何电子设备时,保证所连的设备电源已经关掉.同样,要保证所有与该设备有相连的设备的电源都要关掉.EnsurethatyoufollowallapplicableelectricalcodeswhenwiringtheS7-200andrelatedequipment.Installandoperateallequipmentaccordingtoallapplicablenationalandlocalstandards.Contactyourlocalauthoritiestodeterminewhichcodesandstandardsapplytoyourspecificcase.在进行S7-200的走线与进行设备连接时要确保你遵循了S7_200使用手册.在进行安装和操作S7_200时,要参照国际和地方的标准.联系当地部门,看那个规范和标准适合你的案例设计.WarningAttemptstoinstallorwiretheS7-200orrelatedequipmentwithpowerappliedcouldcauseelectricshockorfaultyoperationofequipment.FailuretodisableallpowertotheS7-200andrelatedequipmentduringinstallationorremovalprocedurescouldresultindeathorseriousinjurytopersonnel,and/ordamagetoequipment.警告:在实际的使用中,安装或布线或连接设备可能会产生电震,或使设备操作不能正常运行,在安装和裁减模块过程中,没有断开所有的电源,将会导致人员死亡或会受到严重的伤害,又或会对设备产生损坏..AlwaysfollowappropriatesafetyprecautionsandensurethatpowertotheS7-200isdisabledbeforeattemptingtoinstallorremovetheS7-200orrelatedequipment.在安装,移去S7_200设备或联接设备时,要严格地遵循正确安全规范和保证所有连到S7_200的电源都是断掉的.AlwaystakesafetyintoconsiderationasyoudesignthegroundingandwiringofyourS7-200system.Electroniccontroldevices,suchastheS7-200,canfailandcancauseunexpectedoperationoftheequipmentthatisbeingcontrolledormonitored.Forthisreason,youshouldimplementsafeguardsthatareindependentoftheS7-200toprotectagainstpossiblepersonalinjuryorequipmentdamage.在设计S7_200的布线时要把把安全问题放在首位.就S7_200控制器来说,它可以使到处于被控的设备不会工作,或会产生不可预知的误操作.正因如此,你要进行除S7_200系统设计外的安全保护,以免产生设备损坏或人员伤亡.WarningControldevicescanfailinanunsafecondition,resultinginunexpectedoperationofcontrolledequipment.Suchunexpectedoperationscouldresultindeathorseriousinjurytopersonnel,and/ordamagetoequipment.Useanemergencystopfunction,electromechanicaloverrides,orotherredundantsafeguardsthatareindependentoftheS7-200.警告:控制器件在不稳定情况下,会不能工作,并可导致控制设备不正常操作.这种未知的操作会导致人员伤亡或会导致仪器损坏.设计独立于S7_200之外的紧急停止开关,或脚踏开关,或其它的安全措施是很有必要.2)GuidelinesforIsolationS7-200ACpowersupplyboundariesandI/OboundariestoACcircuitsarerated1500VAC.TheseisolationboundarieshavebeenexaminedandapprovedasprovidingsafeseparationbetweenAClineandlowvoltagecircuits.隔离规则:S7_200直流电的供电电压上下限和I/0口到AC电路的上下限是1500V.这类型.在AC线路与低压线路间的隔离已经被测试过并被证明是一种可提供安全隔离情况.AlllowvoltagecircuitsconnectedtoanS7-200,suchas24Vpower,mustbesuppliedfromanapprovedsourcethatprovidessafeisolationfromAClineandotherhighvoltages.SuchsourcesincludedoubleinsulationasdefinedininternationalelectricalsafetystandardsandhaveoutputsthatareratedasSELV,PELV,Class2,orLimitedPoweraccordingtovariousstandards.所有连接到S7_200的低电压,如24V电源都必须是要确保安全的,并是从AC线路或高压电压中进行了隔离的电源.这样的电源包括在国际电气标准规定的双重隔离的电源和具有输出达到SELV,PELV,2类标准的电源,或是各种标准限定了的电源.WarningUseofnon-isolatedorsingleinsulationsuppliestosupplylowvoltagecircuitsfromanAClinecanresultinhazardousvoltagesappearingoncircuitsthatareexpectedtobetouchsafe,suchascommunicationscircuitsandlowvoltagesensorwiring.警告:使用没有隔离或单绝缘的电源,从AC中电路中获得电压来提供给低电压电路.将会导致危险电压出现在那些本来安全的电路中,如通信电路和低电压传感器电路中.Suchunexpectedhighvoltagescouldresultindeathorseriousinjurytopersonnel,and/ordamagetoequipment.这种未知的电压会导致人员伤亡,又或会导致仪器损坏.Onlyusehighvoltagetolowvoltagepowerconvertersthatareapprovedassourcesoftouchsafe,limitedvoltagecircuits.只有利有高电压到低电压的转换器来限定电压电路,要求这种转换器是经过验证合格.3)GuidelinesforGroundingtheS7-200ThebestwaytogroundyourapplicationistoensurethatallthecommonandgroundconnectionsofyourS7-200andrelatedequipmentaregroundedtoasinglepoint.Thissinglepointshouldbeconnecteddirectlytotheearthgroundforyoursystem.S7_200的接地规则:最好的接地方法是:让所有的公共端,S7_200的地相关的连接设备接地到同一个点.这个点要被直接连接到地球表面的地.Forimprovedelectricalnoiseprotection,itisrecommendedthatallDCcommonreturnsbeconnectedtothesamesingle-pointearthground.Connectthe24VDCsensorsupplycommon(M)toearthground.为了减少电磁噪声的干扰,建议所有直流电的公共回路要连到同一个地点.把24V直流传感器的电源的公共端连到地.Allgroundwiresshouldbeasshortaspossibleandshouldusealargewiresize,suchas2mm2(14AWG).所有的线路要尽可能短,且要用粗的线径,如2mm大小.Whenlocatinggrounds,remembertoconsidersafetygroundingrequirementsandtheproperoperationofprotectiveinterruptingdevices.当定位地点时,要记得考虑安全接地的要求,和合理进行短路的情况的保护.4)GuidelinesforWiringtheS7-200WhendesigningthewiringforyourS7-200,provideasingledisconnectswitchthatsimultaneouslyremovespowerfromtheS7-200CPUpowersupply,fromallinputcircuits,andfromalloutputcircuits.Provideover-currentprotection,suchasafuseorcircuitbreaker,tolimitfaultcurrentsonsupplywiring.Youmightwanttoprovideadditionalprotectionbyplacingafuseorothercurrentlimitineachoutputcircuit.4)S7_200的布线当设计S7_200的走线时,要提供一个没有接连的开关,它可以从S7_200的电源,从整个输入电源电路,和从整个输出电源电路中同时断开.提供一个过流保护电路,如保险丝或断路开关,来保护电路.可以在每一个输出电路放置保险丝或其它的限流电路来提供一个额外的的保护.Installappropriatesurgesuppressiondevicesforanywiringthatcouldbesubjecttolightningsurges.为任何的配线安装合适的镇流器可以减少电流扰动.Avoidplacinglow-voltagesignalwiresandcommunicationscablesinthesamewiretraywithACwiresandhigh-energy,rapidlyswitchedDCwires.Alwaysroutewiresinpairs,withtheneutralorcommonwirepairedwiththehotorsignal-carryingwire.尽量避免低压电信号线和通信线缆与AC电路高能量,和快速DC开关电路相平行.布线总是利用一条中立的电路或是公共线路与信号线一起来布线的.Usetheshortestwirepossibleandensurethatthewireissizedproperlytocarrytherequiredcurrent.Theconnectoracceptswiresizesfrom2mm2to0.3mm2(14AWGto22AWG).Useshieldedwiresforoptimumprotectionagainstelectricalnoise.Typically,groundingtheshieldattheS7-200givesthebestresults.线路尽可能短,同时保证你的线宽可以通过所要求的电流.接口处的授线线宽范围:2MM-0.3MMWhenwiringinputcircuitsthatarepoweredbyanexternalpowersupply,includeanover-currentprotectiondeviceinthatcircuit.Externalprotectionisnotnecessaryforcircuitsthatarepoweredbythe24VDCsensorsupplyfromtheS7-200becausethesensorsupplyisalreadycurrent-limited.当布置由外电源供电的输入电路时,要考虑到过流保护.外部电路的电保护是不必要的,因为由S7_200提供的24V传感器电压已经设计了电流限制措施.MostS7-200moduleshaveremovableconnectorsforuserwiring.(RefertoAppendixAtodetermineifyourmodulehasremovableconnectors.)Topreventlooseconnections,ensurethattheconnectorisseatedsecurelyandthatthewireisinstalledsecurelyintotheconnector.Toavoiddamagingtheconnector,becarefulthatyoudonotover-tightenthescrews.Themaximumtorquefortheconnectorscrewis0.56N-m(5inch-pounds).大部分的S7_200模块都会为用户提供可以移动的接口(可参见附录A),为了防止不良连接,要确保连接头已经被接稳,还要保证到接口的电线要稳固的接到了接口.为了防止损坏了接口,上螺丝钉时不用过紧.螺丝的最大的扭距是0.56N_mTohelppreventunwantedcurrentflowsinyourinstallation,theS7-200providesisolationboundariesatcertainpoints.Whenyouplanthewiringforyoursystem,youshouldconsidertheseisolationboundaries.RefertoAppendixAfortheamountofisolationprovidedandthelocationoftheisolationboundaries.Isolationboundariesratedlessthan1500VACmustnotbedependedonassafetyboundaries.为了防止破坏性的电流流入装置,S7_200在某些地方提供了一些界限.在计划系统时,要考虑这些隔离界限.详情参照附录A,它给出了所有隔离和隔离界限的定位.隔离上限小于1500V直流电压,不能认为就是安全的电压.Tip：Foracommunicationsnetwork,themaximumlengthofthecommunicationscableis50mwithoutusingarepeater.ThecommunicationsportontheS7-200isnon-isolated.提示:对于通信网络来说,在没有转发器的情况下,最长的通信线缆长度是50m.在S7_200中的通信端口是没有隔离的.5.GuidelinesforInductiveLoadsYoushouldequipinductiveloadswithsuppressioncircuitstolimitvoltagerisewhenthecontroloutputturnsoff.Suppressioncircuitsprotectyouroutputsfromprematurefailureduetohighinductiveswitchingcurrents.Inaddition,suppressioncircuitslimittheelectricalnoisegeneratedwhenswitchinginductiveloads.电感负载的规则:在控制电压关掉时,系统要配置电感负载抑制电路来限制电压的上升.抑制电路可防止由于高电感的电流切换时产生的破坏性电流导致输出电路损坏.另外,抑制电路可以限制电磁噪声,它是由电感负载的切换产生.TipTheeffectivenessofagivensuppressioncircuitdependsontheapplication,andyoumustverifyitforyourparticularuse.Alwaysensurethatallcomponentsusedinyoursuppressioncircuitareratedforuseintheapplication.提示:有效的郁制电路是根据应用来设计,要在特殊的应用中进行改变.要确保应用系统的所有元器件符合应用的要求.1)DCOutputsandRelaysThatControlDCLoadsTheDCoutputshaveinternalprotectionthatisadequateformostapplications.SincetherelayscanbeusedforeitheraDCoranACload,internalprotectionisnotprovided.直流输出和控制直流负载的继电器直流电源输出具有的保护设计已满足大多数的应用.因此断电器能够被用到其它没有内部的保护的直流负载和交流负载中.交流的电Figure3showsasamplesuppressioncircuitforaDCload.Inmostapplications,theadditionofadiode(A)acrosstheinductiveloadissuitable,butifyourapplicationrequiresfasterturn-offtimes,thentheadditionofaZenerdiode(B)isrecommended.BesuretosizeyourZenerdiodeproperlyfortheamountofcurrentinyouroutputcircuit.图3给出针对直流负载的简单镇流电路.在大部分的应用中,外部的连接电感两端的二极管要匹配.假如需要一个更短的截止时间,建议增加稳压二极管.务必让稳压二极管稳定参数要与输出电路中电流大小相符.Figure3SuppressionCircuitforaDCLoad图3.针对DC抑制电路2)ACOutputsandRelaysThatControlACLoadsTheACoutputshaveinternalprotectionthatisadequateformostapplications.SincetherelayscanbeusedforeitheraDCoranACload,internalprotectionisnotprovided.AC输出与控制AC负载的继电器AC输出电路拥有的内部保护电路可以满足大部分的应用.因此断电器的可以用在没有内部保护电路DC电路或AC的负载的中Figure4SuppressionCircuitforanACLoad图4针对AC负载的抑制电路Figure4showsasamplesuppressioncircuitforanACload.WhenyouusearelayorACoutputtoswitch115V/230VACloads,placeresistor/capacitornetworksacrosstheACloadasshowninthisfigure.Youcanalsouseametaloxidevaristor(MOV)tolimitpeakvoltage.EnsurethattheworkingvoltageoftheMOVisatleast20%greaterthanthenominallinevoltage.图4针对AC负载的简单的抑制电路,当用继电器或输出电压来切换115/230V的交流电压时,要像图示那样,用电阻/电容网络来接在直流负载的两端.也可以用金属氧化变阻器来限制电压峰值.以保证金属氧化变阻器的工作电压来最少比标称电压大20%.NoticeWhenrelayexpansionmodulesareusedtoswitch230VACinductiveloads,theexternalresistor/capacitornoisesuppressioncircuitmustbeplacedacrosstheACloadasshowninFigure4注意:当用继电器扩展模块来切换230V交流电感负载时,外部电阻/电容的噪声抑制电路要像图4那样接在交流负载的两端.6.GuidelinesforLampLoadsLamploadsaredamagingtorelaycontactsbecauseofthehighturn-onsurgecurrent.Thissurgecurrentwillnominallybe10to15timesthesteadystatecurrentforaTungstenlamp.Areplaceableinterposingrelayorsurgelimiterisrecommendedforlamploadsthatwillbeswitchedalargenumberoftimesduringthelifetimeoftheapplication.6.电灯负载规则电灯负载是对继电器的连接有害的,因为它打开时具有很高的冲击电流.对于钨灯来说,它的值将会稳态电流的10到15倍.建议用用中介继电器或波动限制器来做电灯的负载保护,它们在应用中能够用很多次 .NewWordsandExpressionsmountinghole安装孔,固定孔clipn.接线柱，线夹；夹(片)DIN=DeutschelndustrieNormen德国工业标准[联邦德国]layoutv.布置,摆开,展示,安排,投资layoutn.设计，规划，安排，(页面)布局，布置(图)；版面，(打印)格式；轮廓[LD]configurevi.配置,设定；vt.安装，装配，配置routing路由选择，又称“选路”。naturalconvectioncooling自然对流冷却clearance[电气]间隙ambienttemperature环境温度orientation