电子信息类专业英语Unit-15-Temperature-Sensors-课件

Unit15TemperatureSensorsTextKeywordsTechnicaltermsExpressionsNotestothetextUnit15TemperatureSensorsTText

Oneoftheprimarymethodsforelectricalmeasurementoftemperatureinvolveschangesintheelectricalresistanceofcertainmaterials.Inthis,aswellasothercases,theprinciplemeasurementtechniqueistoplacethetemperature-sensingdeviceincontactwiththeenvironmentwhosetemperatureistobemeasured.Thesensingdevicethentakesonthetemperatureoftheenvironment.Thusameasureofitsresistanceindicatesthetemperatureofthedeviceandtheenvironmentmustwaituntilthedevicecomesintothermalequilibriumwiththeenvironment.ThetwobasicdevicesusedastheResistance-TemperatureDetector(RTD),Text

Oneoftheprimarymethbasedonthevariationofmetalresistancewithtemperature,andthethermistor,basedonthevariationofsemiconductorresistancewithtemperature.

Thereexistsanotherdependenceofelectricalbehaviorofmaterialsontemperaturethatformsthebasisofalargepercentageofalltemperaturemeasurement.Thiseffectischaracterizedbyavoltage-generatingsensorinwhichanelectromotiveforce(emf)isproducedthatisproportionaltotemperature.Suchanemfisfoundtobealmostlinearwithtemperatureandveryrepeatableforconstantmaterials.Devicesthatmeasuretemperatureonthebasisofthisthermoelectricprinciplearecalledthermocouples(TCs).basedonthevariationofmetaHerewe’llbrieflydiscussthecharacteristicsofResistance-TemperatureDetector(RTD).

AResistance-TemperatureDetector(RTD)isatemperaturesensorthatisbasedontheprinciplesthatmetalresistanceincreasingwithtemperature.Metalusedinthesedevicesvaryfromplatinum,whichisveryrepeatable,quitesensitive,andveryexpensive,tonickel,whichisnotquitsasrepeatable,moresensitive,andlessexpensive.Herewe’llbrieflydiscusstSensitivityAnestimateofRTDsensitivitycanbenotedfromtypicalvaluesofa0,thelinearfractionalchangeinresistancewithtemperature.Forplatinum,thisnumberistypicallyontheorderof0.004/℃,andfornickelatypicalvalueis0.005/℃.Thus,withplatinum,forexample,achangeofonly0.4Ωwouldbeexpectedfora100ΩRTDifthetemperatureischangedby1℃.Usually,aspecificationwillprovidecalibrationinformationeitherasagraphofresistanceversustemperatureorasatableofvaluesfromwhichthesensitivitycanbedetermined.Forthesamematerials,however,thisnumberisrelativelyconstantbecauseitisafunctionofresistivity.SensitivityAnestimateofResponseTimeIngeneral,RTDhasaresponsetimeof0.5to5sormore.Theslownessofresponseisdueprincipallytotheslownessofthermalconductivityinbringingthedeviceintothermalequilibriumwithitsenvironment.

ConstructionARTD,ofcourse,issimplyalengthofwirewhoseresistanceistobemonitoredasafunctionoftemperature.Theconstructionistypicallysuchthatthewireiswoundonaform(inacoil)toachievesmallsizeandimprovethermalconductivitytodecreaseresponsetime.Inmanycases,thecoilisprotectivetubethatinevitablyincreasesresponsetimebutmaybenecessaryinhostileenvironments.Alooselyappliedstandardsetstheresistanceatmultiplesof100Ωforatemperatureof0℃.ResponseTimeIngeneral,RRangeTheeffectiverangeofRTDsdependsprincipallyonthetypeofwireusedastheactiveelement.Thus,atypicalplatinumRTDmayhavearangeof－100℃to650℃,whereasaRTDconstructedfromnickelmighttypicallyhaveaspecifiedrangeof－180℃to300℃.RangeTheeffectiverangeoKeywords

sensor n.传感器

thermal adj.热的，热量的

equilibrium n.平衡，平静，均衡

detector n.探测器，检波器，检电器

thermistor n.热敏电阻

thermoelectric adj.热电的

electromotive adj.电动的

thermocouple n. [物]热电偶

platinum n.白金，铂

nickel n. [化]镍Keywords

sensor n.传感器

repeatable adj.可重复的

sensitivity n.敏感，灵敏(度)，灵敏性

fractional adj.部分的

calibration n.标度，刻度，校准

graph n.图表，曲线图

versus prep.与…相对

resistivity n.抵抗力，电阻系数

conductivity n.传导性，传导率

inevitably adv.不可避免

hostile adj.敌对的，敌方的repeatable adj.可重复的

senTechnicalterms

temperature-sensingdevice 温度敏感器件

thermalequilibrium 热量平衡

Resistance-TemperatureDetector(RTD) 电阻温度计

voltage-generatingsensor 产生电压的传感器

electromotiveforce(emf) 电动势

theactiveelement 有源元件Technicalterms

temperature-Expressions

incontactwith… 与…相关，联系

comeinto 达到，得到

basedon 基于

alargepercentageof 很大的百分比

belinearwith… 与…成线性

onthebasisof… 以…为基础Expressions

incontactwith…Notestothetext

1.Inthis,aswellasothercases,theprinciplemeasurementtechniqueistoplacethetemperature-sensingdeviceincontactwiththeenvironmentwhosetemperatureistobemeasured.

无论何种测量，其测量技术的原理都是将温度传感装置与被测温的环境相接触。句中，“toplacethetemperature-sensingdevice…”至句末的不定式用作表语；“whosetemperatureistobemeasured”为定语从句，修饰“environment”；“tobemeasured”是从句中的不定式作表语成分。Notestothetext

1.Inthis2.ThetwobasicdevicesusedastheResistance-TemperatureDetector(RTD),basedonthevariationofmetalresistancewithtemperature,andthethermistor,basedonthevariationofsemiconductorresistancewithtemperature.

使用的两个测温器件分别是电阻温度计和热敏电阻，其中前者是金属电阻随温度变化而变化，后者是半导体电阻随温度变化而变化。句中的“basedonthevariationofmetalresistancewithtemperature”修饰“theResistance-TemperatureDetector(RTD)”；“basedonthevariationofsemiconductorresistancewithtemperature”修饰“thethermistor”；“theResistance-TemperatureDetector”和“thethermistor”相并列。2.Thetwobasicdevicesuse3. Metalusedinthesedevicesvaryfromplatinum,whichisveryrepeatable,quitesensitive,andveryexpensive,tonickel,whichisnotquitsasrepeatable,moresensitive,andlessexpensive.

测温装置使用不同的金属制成，可以是重复性好、灵敏度高、价格高的铂，也可以是重复性不太好，但灵敏度更高、价格较低的镍。句中的 “whichisveryrepeatable,quitesensitive,andveryexpensive”修饰“platinum”；“whichisnotquitsasrepeatable,moresensitive,andlessexpensive”修饰“nickel”。3. MetalusedinthesedeviUnit15TemperatureSensorsTextKeywordsTechnicaltermsExpressionsNotestothetextUnit15TemperatureSensorsTText

Oneoftheprimarymethodsforelectricalmeasurementoftemperatureinvolveschangesintheelectricalresistanceofcertainmaterials.Inthis,aswellasothercases,theprinciplemeasurementtechniqueistoplacethetemperature-sensingdeviceincontactwiththeenvironmentwhosetemperatureistobemeasured.Thesensingdevicethentakesonthetemperatureoftheenvironment.Thusameasureofitsresistanceindicatesthetemperatureofthedeviceandtheenvironmentmustwaituntilthedevicecomesintothermalequilibriumwiththeenvironment.ThetwobasicdevicesusedastheResistance-TemperatureDetector(RTD),Text

Oneoftheprimarymethbasedonthevariationofmetalresistancewithtemperature,andthethermistor,basedonthevariationofsemiconductorresistancewithtemperature.

Thereexistsanotherdependenceofelectricalbehaviorofmaterialsontemperaturethatformsthebasisofalargepercentageofalltemperaturemeasurement.Thiseffectischaracterizedbyavoltage-generatingsensorinwhichanelectromotiveforce(emf)isproducedthatisproportionaltotemperature.Suchanemfisfoundtobealmostlinearwithtemperatureandveryrepeatableforconstantmaterials.Devicesthatmeasuretemperatureonthebasisofthisthermoelectricprinciplearecalledthermocouples(TCs).basedonthevariationofmetaHerewe’llbrieflydiscussthecharacteristicsofResistance-TemperatureDetector(RTD).

AResistance-TemperatureDetector(RTD)isatemperaturesensorthatisbasedontheprinciplesthatmetalresistanceincreasingwithtemperature.Metalusedinthesedevicesvaryfromplatinum,whichisveryrepeatable,quitesensitive,andveryexpensive,tonickel,whichisnotquitsasrepeatable,moresensitive,andlessexpensive.Herewe’llbrieflydiscusstSensitivityAnestimateofRTDsensitivitycanbenotedfromtypicalvaluesofa0,thelinearfractionalchangeinresistancewithtemperature.Forplatinum,thisnumberistypicallyontheorderof0.004/℃,andfornickelatypicalvalueis0.005/℃.Thus,withplatinum,forexample,achangeofonly0.4Ωwouldbeexpectedfora100ΩRTDifthetemperatureischangedby1℃.Usually,aspecificationwillprovidecalibrationinformationeitherasagraphofresistanceversustemperatureorasatableofvaluesfromwhichthesensitivitycanbedetermined.Forthesamematerials,however,thisnumberisrelativelyconstantbecauseitisafunctionofresistivity.SensitivityAnestimateofResponseTimeIngeneral,RTDhasaresponsetimeof0.5to5sormore.Theslownessofresponseisdueprincipallytotheslownessofthermalconductivityinbringingthedeviceintothermalequilibriumwithitsenvironment.

ConstructionARTD,ofcourse,issimplyalengthofwirewhoseresistanceistobemonitoredasafunctionoftemperature.Theconstructionistypicallysuchthatthewireiswoundonaform(inacoil)toachievesmallsizeandimprovethermalconductivitytodecreaseresponsetime.Inmanycases,thecoilisprotectivetubethatinevitablyincreasesresponsetimebutmaybenecessaryinhostileenvironments.Alooselyappliedstandardsetstheresistanceatmultiplesof100Ωforatemperatureof0℃.ResponseTimeIngeneral,RRangeTheeffectiverangeofRTDsdependsprincipallyonthetypeofwireusedastheactiveelement.Thus,atypicalplatinumRTDmayhavearangeof－100℃to650℃,whereasaRTDconstructedfromnickelmighttypicallyhaveaspecifiedrangeof－180℃to300℃.RangeTheeffectiverangeoKeywords

sensor n.传感器

thermal adj.热的，热量的

equilibrium n.平衡，平静，均衡

detector n.探测器，检波器，检电器

thermistor n.热敏电阻

thermoelectric adj.热电的

electromotive adj.电动的

thermocouple n. [物]热电偶

platinum n.白金，铂

nickel n. [化]镍Keywords

sensor n.传感器

repeatable adj.可重复的

sensitivity n.敏感，灵敏(度)，灵敏性

fractional adj.部分的

calibration n.标度，刻度，校准

graph n.图表，曲线图

versus prep.与…相对

resistivity n.抵抗力，电阻系数

conductivity n.传导性，传导率

inevitably adv.不可避免

hostile adj.敌对的，敌方的repeatable adj.可重复的

senTechnicalterms

temperature-sensingdevice 温度敏感器件

thermalequilibrium 热量平衡

Resistance-TemperatureDetector(RTD) 电阻温度计

voltage-generatingsensor 产生电压的传感器

electromotiveforce(emf) 电动势

theactiveelement 有源元件Technicalterms

temperature-Expressions

incontactwith… 与…相关，联系

comeinto 达到，得到

basedon 基于

alargepercentageof 很大的百分比

belinearwith… 与…成线性

onthebasisof… 以…为基础Expressions

incontactwith…Notestothetext

1.Inthis,aswellasothercases,theprinciplemeasurementtechniqueistoplacethetemperature-sensingdeviceincontactwiththeenvironmentwhosetemperatureistobemeasured