Kev sib piv ntawm qhov zoo thiab qhov tsis zoo ntawm plaub lub ntsiab ntsuas kub ntsuas

Kev xaiv cov khoom siv ntsuas kub yuav zoo li qhov tsis tseem ceeb, tab sis vim muaj ntau yam khoom siv, txoj haujlwm no tuaj yeem ua rau muaj kev ntshai heev. Nyob rau hauv tsab xov xwm no, tus sau yuav qhia txog plaub hom kub sensors (RTDs), thermocouples, thermistors, thiab integrated circuit (IC) sensors nrog digital thiab analog interfaces) thiab sib tham txog qhov zoo thiab qhov tsis zoo ntawm txhua hom sensor.
Los ntawm qhov kev nkag siab ntawm lub cev, seb qhov ntsuas kub puas haum rau koj daim ntawv thov yuav nyob ntawm qhov yuav tsum tau muaj qhov kub thiab txias, qhov tseeb, linearity, kev daws teeb meem, kev ua haujlwm, kev siv hluav taws xob, kev daws qhov loj me, txoj kev teeb tsa (nto mount txoj kev, los ntawm lub qhov ntxig txoj kev , thiab circuit board sab nrauv installation txoj kev), nrog rau qhov yooj yim ntawm kev tsim hluav taws xob tsim kev txhawb nqa. RTD
Thaum ntsuas qhov tsis kam ntawm RTD thaum hloov nws qhov kub, cov lus teb yog yuav luag linear, ua zoo li tus resistor. Raws li pom nyob rau hauv daim duab 1, qhov kev tiv thaiv nkhaus ntawm RTD tsis yog tag nrho linear, tab sis muaj ob peb theem ntawm kev sib txawv (qhia ib txoj kab ncaj nraim siv raws li kev siv) - tab sis nws yog qhov kev kwv yees tau zoo thiab muaj tseeb. Txhawm rau them nyiaj rau qhov tsis muaj qhov tsis sib xws, feem ntau cov neeg tsim qauv digitize qhov ntsuas qhov ntsuas qhov ntsuas thiab siv cov lus saib hauv microcontrollers los siv cov kev kho kom raug. Qhov rov ua tau zoo thiab ruaj khov nyob rau hauv qhov kub thiab txias (kwv yees li -250 degree C rau +750 degree C) ua rau RTD muaj txiaj ntsig zoo hauv cov ntawv thov siab, suav nrog ntsuas qhov ntsuas kub ntawm cov kua lossis roj hauv cov kav dej thiab cov ntim loj. .
Qhov nyuaj ntawm circuits siv los ua RTD analog signals feem ntau txawv nyob ntawm daim ntawv thov. Cheebtsam xws li amplifiers thiab analog-to-digital converters (ADCs), uas tsim lawv tus kheej yuam kev, yog indispensable. Tsuas yog muab lub zog rau lub sensor thaum tsim nyog rau kev ntsuas - koj tuaj yeem ua tiav kev ua haujlwm qis zog los ntawm txoj kev no, tab sis qhov no yuav ua rau lub voj voog ntau dua. Tsis tas li ntawd, lub zog xav tau rau lub zog ntawm lub sensor kuj nce nws qhov kub thiab txias, yog li cuam tshuam rau kev ntsuas qhov tseeb. Nrog tsuas yog ob peb amps ntawm tam sim no, qhov kev ua kom sov ntawm tus kheej no yuav ua rau muaj qhov kub thiab txias (cov kev ua yuam kev no yog kho tau tab sis yuav tsum tau xav txog ntxiv). Tsis tas li ntawd, thov nco ntsoov tias tus nqi ntawm hlau qhov txhab platinum RTDs lossis nyias zaj duab xis RTDs tuaj yeem siab heev, tshwj xeeb tshaj yog thaum piv rau tus nqi ntawm I-sensors.
Thermistor
Thermistor yog lwm hom electropositive sensor. Muaj ntau yam muaj cov thermistors, xws li cov khoom lag luam raug nqi mus rau cov khoom lag luam siab. Tus nqi qis thiab tsis tshua muaj siab thermistor tuaj yeem ua qhov ntsuas yooj yim lossis lub teb chaws tus nqi nrhiav kev ua haujlwm - cov hom resistors xav tau ntau yam (xws li kev sib piv, kev siv, thiab cov resistors discrete), tab sis pheej yig heev thiab muaj cov khoom kub tsis zoo, raws li qhia hauv daim duab. 2. Yog tias koj yuav tsum ntsuas qhov ntsuas kub ntau, koj yuav tsum tau ua ntau txoj haujlwm linearization. Calibration ntawm ob peb lub ntsiab lus kub yuav tsim nyog. Txhawm rau kom ua tiav qhov raug siab dua, tus nqi kim dua thiab nruj dua thermistor array tuaj yeem siv los pab daws qhov teeb meem no tsis yog kab, tab sis qhov array no feem ntau tsis tshua muaj siab dua li ib tus thermistor.

Vim muaj kev nyuaj siab ntau ntxiv thiab tus nqi ntawm ntau lub tshuab dhia taw tes, tus nqi qis qis feem ntau tsuas yog siv rau cov ntawv thov uas yuav tsum tau ua haujlwm tsawg, suav nrog toasters, kas fes txiag, tub yees, thiab tshuab ziab plaub hau. Tsis tas li ntawd, thermistors kuj raug kev txom nyem los ntawm cov teeb meem cua sov ntawm tus kheej (feem ntau ntawm qhov kub siab dua, thaum lawv tsis kam qis dua). Raws li cov ntaub ntawv ntawm RTDs, lub hauv paus ua rau tsis tuaj yeem siv cov thermistor ntawm qhov hluav taws xob qis hluav taws xob tseem tsis tau txheeb xyuas - tab sis thov nco ntsoov tias qhov qis dua qhov tso tawm tag nrho, qhov qis dua qhov kev nkag siab ntawm lub cev nws ncaj qha hloov pauv raws li cov khoom siv hluav taws xob. Cov yam ntxwv ntawm analog-to-digital converters (ADCs). Kev siv hluav taws xob tsawg kuj yuav tsum tau ua kom muaj kev sib tw hauv Circuit Court kom ua tau zoo heev rau cov teeb meem tshwm sim los ntawm lub suab nrov. Thermistors tuaj yeem ua haujlwm nyob rau hauv qhov kub ntawm -100 degree C rau +500C, txawm hais tias feem ntau cov thermistor muaj qhov ntsuas kub siab tshaj plaws ua haujlwm ntawm +100 degree C rau +150 degree C thermocouples
Lub thermocouple suav nrog kev sib txuas ntawm ob lub xov hlau ua los ntawm cov khoom sib txawv. Piv txwv li, a) hom thermocouple yog ua los ntawm hlau thiab constantan. Raws li pom nyob rau hauv daim duab 3, hu rau 1 yog nyob rau ntawm qhov kub thiab txias yuav tsum tau ntsuas, thaum hu rau 2 thiab hu 3 yog muab tso rau ntawm qhov sib txawv kub ntsuas siv LM35 analog kub sensors. Cov zis voltage yog kwv yees li proportional rau qhov sib txawv ntawm ob qhov ntsuas kub no.
Vim tias qhov rhiab heev ntawm cov thermocouples yog qhov tsawg heev (ntawm qhov kev txiav txim ntawm kaum ntawm microvolts ib degree Celsius), koj yuav xav tau lub tshuab hluav taws xob qis qis los tsim cov khoom siv hluav taws xob. Tsis pub dhau qhov ua haujlwm ntawm cov thermocouples, qhov tsis sib xws hauv qhov kub thiab txias rau qhov hloov pauv hluav taws xob feem ntau yuav tsum tau them nyiaj circuits lossis saib cov lus, ib yam li RTDs thiab thermocouples. Txawm li cas los xij, txawm hais tias cov teeb meem no, cov thermocouples tseem nrov heev, tshwj xeeb tshaj yog tsim rau lub qhov cub, lub tshuab rhaub dej, qhov cub, cov cuab yeej kuaj, thiab lwm yam kev kho mob - vim tias cov thermal zoo ntawm cov thermocouples yog qhov tsawg heev, thiab kev ua haujlwm kub (uas tuaj yeem txuas ntxiv mus. mus rau saum 2300 degree) yog dav heev:
IC sensor
IC sensors tuaj yeem ua haujlwm nyob rau hauv qhov ntsuas kub ntawm {{{0}}} degree C rau +150 degree C - xaiv|C sensors tuaj yeem ua haujlwm txog li +200 degree C. Muaj ntau hom kev sib xyaw IC sensors, tab sis plaub qhov kev sib xyaw ua ke IC sensors feem ntau yog cov khoom siv analog tso tawm, cov khoom siv digital interface, cov chaw taws teeb kub sensors, thiab cov uas muaj qhov kub thiab txias ua haujlwm. (kub hloov). Analog output devices (feem ntau yog qhov tso zis hluav taws xob, tab sis qee qhov kuj muaj cov zis tam sim no) feem ntau zoo li kev daws teeb meem thaum lawv xav tau ADC los digitize lub teeb liab tso zis. Cov khoom siv digital interface feem ntau siv ob lub xov tooj sib txuas (12C lossis PMBus) thiab muaj cov ADCs built-in. Ntxiv rau qhov ntsuas kub hauv cheeb tsam, cov chaw taws teeb tswj qhov kub thiab txias kuj muaj ib lossis ntau qhov khoom siv rau kev saib xyuas tej thaj chaw deb diode kub - lawv feem ntau muab tso rau hauv cov ICs sib xyaw ua ke (xws li cov txheej txheem lossis cov phiaj xwm phiaj xwm rooj vag arrays (FPGAs)). Thaum qhov ntsuas kub tau mus txog, lub ntsuas sov tuaj yeem muab lub tswb yooj yim. Muaj ntau yam txiaj ntsig rau kev siv IC sensors, suav nrog: kev siv hluav taws xob tsawg; Muaj peev xwm muab cov khoom ntim me me (qee qhov me me li 0.8mmx0.8mm); Tus nqi qis qis kuj tuaj yeem ua tiav hauv qee yam kev siv.