Dab tsi yog cov hom kub sensors
Tso lus
Kub sensors yog cov cuab yeej tseem ceeb hauv engineering niaj hnub, kev tshawb fawb tshawb fawb, thiab lub neej txhua hnub. Lawv cia koj saib xyuas thiab tswj cov cua sov hauv ntau qhov chaw. Thermocouples, tiv thaiv qhov kub thiab txias (RTDs), thermistors (NTC thiab PTC versions), thiab kev sib koom ua ke (IC) kub sensors yog hom nrov tshaj plaws. Thermocouples thiab RTDs yog cov khoom siv ntau tshaj plaws siv hauv cov chaw tsim khoom vim tias lawv ntseeg tau, hloov tau, thiab tuaj yeem ua haujlwm hauv qhov chaw nyuaj. Txhua hom sensor ua haujlwm ntawm cov qauv sib txawv, uas txhais tau hais tias lawv muaj cov txiaj ntsig sib txawv ntawm qhov kub thiab txias, qhov tseeb, lub sijhawm teb, tus nqi, thiab kev hloov pauv mus rau qhov chaw sib txawv. Qhov no cia cov engineers xaiv cov kev daws teeb meem zoo tshaj plaws rau ib qho xwm txheej, xws li kev tswj cov txheej txheem, HVAC systems, khoom siv kho mob, kev siv tsheb, thiab IoT cov cuab yeej.
Thermocouples
Thermocouples ua haujlwm vim tias Seebeck effect (thermoelectric effect), uas tshwm sim thaum ob lub hlau sib txawv sib txuas ntawm ib qho kawg kom ntsuas qhov sib txuas. Ib qho me me electromotive quab yuam (voltage) yog tsim thaum muaj qhov sib txawv ntawm qhov kub thiab txias ntawm qhov kub (ntsuas) kev sib tshuam thiab qhov txias (siv) kev sib tshuam. Qhov no voltage yog ncaj qha ntsig txog qhov sib txawv. Nws muaj peev xwm nrhiav tau qhov kub thiab txias los ntawm kev ntsuas qhov hluav taws xob no thiab ua qhov kev hloov kho kom haum rau qhov ntsuas kub ntawm qhov kev sib tshuam.
Thermocouples tuaj yeem ntsuas qhov kub ntawm ntau yam, los ntawm qis li -200℃mus rau zoo tshaj 2000 degree, nyob ntawm seb cov khoom siv. Qhov no ua rau lawv zoo meej rau qhov chaw kub heev lossis txias heev. Lawv muaj qhov yooj yim, muaj zog tsim uas ua rau lawv ruaj khov thiab muaj peev xwm tiv taus kev poob siab, kev co, thiab hnyav. Thermocouples kuj pheej yig, tsis tas yuav muaj lub zog sab nraud los ua haujlwm, thiab muaj lub sijhawm thermal teb sai, uas yog qhov tseem ceeb hauv cov txheej txheem hloov sai. Tab sis lawv cov teeb liab tso zis yog me ntsis (feem ntau nyob rau hauv lub microvolt ntau), yog li lawv xav tau amplification circuitry, thiab lawv xav tau kev hloov kho txias kom nyob twj ywm. Qee hom kev sib tw yog:
Hom K (nickel-chromium/nickel-silicon): Hom feem ntau, nws ua haujlwm zoo los ntawm -200℃rau +1260℃thiab yog tus nqi tsim nyog thiab tiv taus oxidation.
Hom J (hlau / tooj liab-nickel): Ua haujlwm zoo ntawm qhov kub thiab txias, txog li 750 degree, thiab siv dav hauv kev txo cov huab cua.
Hom S (platinum-rhodium/platinum): Qhov no yog hom hlau zoo uas siv rau hauv siab -precision, siab- daim ntawv thov kub uas nce mus txog 1600℃lossis ntau dua. Nws yog siv nyob rau hauv furnaces thiab aircraft.
Thermocouples tseem ceeb heev hauv kev lag luam uas ua haujlwm nrog kub siab, xws li metallurgy (steel smelting), chemical processing, power generating (boilers and turbines), thiab iav ua.
II. Resistance Temperature Detectors (RTDs)
RTDs nyob ntawm qhov tseeb tias qhov hluav taws xob tsis kam ntawm cov hlau ntshiab, zoo li platinum, hloov pauv hauv txoj kev kwv yees thaum kub hloov. Qhov kev tawm tsam nce mus rau hauv txoj kab ncaj nraim thaum qhov kub thiab txias nce, ua raws li cov cai xws li Daim Ntawv Teev Npe -Van Dusen kab zauv. Pt100 sensor (100 ohms ntawm 0 degree) thiab Pt1000 yog ob hom ntau tshaj.
RTDs yog qhov zoo vim tias lawv muaj tseeb heev (feem ntau yog ± 0.1℃lossis zoo dua), ruaj khov nyob rau lub sijhawm, thiab muaj cov lus teb nyob rau hauv ntau qhov kub thiab txias (feem ntau yog -200℃rau +660℃, tab sis qee qhov qauv tsim tuaj yeem mus ntau dua). Vim li no, lawv zoo dua rau cov haujlwm uas xav tau ntau qhov tseeb, xws li ntsuas qhov chaw kuaj, ua zaub mov, ua tshuaj, thiab tswj HVAC systems. Lawv cov teeb meem tseem ceeb yog lawv siv sij hawm ntev dua los teb vim tias lawv muaj thermal mass ntau dua, lawv raug nqi ntau dua li cov thermocouples, thiab lawv xav tau ib qho excitation tam sim no (qhov tam sim no tsis tu ncua) los ntsuas kev tiv thaiv yam tsis ua yuam kev los ntawm tus kheej - cua sov. Siv peb -wire los yog plaub-xaim teeb yog qhov loj ntxiv vim tias lawv ua rau cov hlau lead ua haujlwm thiab txhim kho qhov tseeb tag nrho ntawm cov kab ke, tshwj xeeb tshaj yog nyob deb.
III. Thermistors
Thermistors yog cov sensors ua los ntawm cov khoom siv hluav taws xob uas hloov lawv qhov kev tiv thaiv ntau heev thaum kub hloov. Lawv muab faib ua NTC (tsis zoo kub coefficient, uas txhais tau hais tias tsis kam mus down raws li kub nce) thiab PTC (zoo kub coefficient, uas txhais tau hais tias tsis kam mus sai heev saum ib lub ntsiab lus).
NTC thermistors yog cov rhiab heev (ntau tshaj li RTDs lossis thermocouples), teb sai, me me, thiab pheej yig. Lawv ua haujlwm zoo nyob rau hauv thaj tsam ntawm -50 txog +150 degrees Celsius (nrog qee qhov nthuav dav). Lawv tau siv ntau hauv kev tswj hwm roj teeb, kev tswj hwm huab cua hauv tsheb, cov khoom siv hauv tsev (xws li lub tub yees thiab qhov cub), thiab cov khoom siv hluav taws xob. Qhov teeb meem tseem ceeb yog tias lawv qhov kev tiv thaiv- qhov kub thiab txias yog qhov tsis zoo heev -linear, uas txhais tau hais tias koj yuav tsum siv lej lossis nrhiav cov lus kom tau txais kev nyeem ntawv raug. Tsis tas li ntawd, lawv muaj teeb meem nrog kev sib hloov pauv yog tias lawv tsis raug ntsuas. PTC thermistors, ntawm qhov tod tes, feem ntau yog siv rau ntau tshaj - tiv thaiv qhov kub thiab txias, txwv tsis pub cov cua sov tam sim no, thiab kev tswj tus kheej cua sov cov ntsiab lus es tsis txhob ntsuas qhov ntsuas tsis tu ncua.
IV. Kub Sensors rau Integrated Circuits (ICs) IC sensors ua ke cov khoom ntsuas, teeb liab txias, thiab qee zaum analog - rau - digital hloov dua siab tshiab rau hauv ib lub silicon nti. Lawv tuaj yeem xa cov analog voltage (xws li 10 mV / degree) lossis digital signals los ntawm cov txheej txheem xws li I²C, SPI, lossis 1-Wire. Qee lub npe nrov yog LM35, DS18B20, thiab TMP series li.
Lawv muaj qhov ua yuam kev tsawg (± 0.5℃ib txwm), teb sai sai, xav tau ob peb qhov chaw sab nraud, thiab yooj yim txuas rau microcontrollers. Qhov no ua rau lawv zoo meej rau cov kab ke, cov khoom siv hluav taws xob, IoT nodes, PCs, thiab cov khoom siv nqa tau yooj yim. Qhov kub ntawm -55 txog +150 degrees Celsius txwv tsis pub lawv siv nyob rau hauv qhov chaw kub heev los yog txias heev, tab sis lawv qhov yooj yim ntawm kev siv thiab muaj peev xwm ua hauj lwm nrog lwm yam khoom siv rau qhov no nyob rau hauv ntau daim ntawv thov tam sim no.
V. Lwm Hom Tshuaj Ntxiv Ntxiv nrog rau lub ntsiab tiv tauj sensors, muaj ntau yam kev xaiv tshwj xeeb uas ua tau raws li cov hom phiaj tshwj xeeb.
Infrared (tsis yog -sib cuag) ntsuas kub ntsuas ntsuas kub yam tsis tau kov cov khoom vim lawv tuaj yeem pom cov hluav taws xob hluav taws xob los ntawm nws. Lawv zoo heev rau kev saib xyuas qhov kub siab (xws li cov hlau molten), txav lub hom phiaj, lossis qhov chaw txaus ntshai. Koj tuaj yeem pom lawv hauv cov ntsuas kub hauv pob ntseg, cov khoom siv pyrometers, thiab kuaj xyuas zaub mov.
Bimetallic thermometers siv qhov sib txawv thermal expansion ntawm ob daim hlau sib txuas kom txav tau tus taw tes. Qhov no ua rau kev nyeem ntawv yooj yim, vam khom yam tsis xav tau lub zog. Lawv ua haujlwm zoo nrog cov ntsuas kub hauv tsev yooj yim, qhov cub, thiab cov ntsuas kev lag luam uas tsis raug.
Fiber optic kub sensors tiv thaiv electromagnetic cuam tshuam, tiv taus corrosion, thiab muaj peev xwm nkag siab nyob rau hauv qhov kev ncua deb vim lawv siv cov yam ntxwv kho qhov muag xws li fluorescence decay los yog interferometry. Lawv tseem ceeb heev nyob rau hauv qhov chaw xws li high-voltage substations, transformers, MRI machines, thiab qhov chaw uas muaj cov khoom tawg lossis cov khoom siv nuclear.
Nyob rau hauv luv luv, thaum xaiv ib tug kub sensor, koj yuav tsum xav txog tej yam xws li yuav ua li cas yog nws yuav tsum tau, qhov dav ntawm qhov kub thiab txias yog npaum li cas, yuav tsum ceev npaum li cas nws yuav tsum tau teb, nws nqi npaum li cas, hnyav npaum li cas nws yuav tsum tau nyob rau hauv ib puag ncig, thiab nws yooj yim npaum li cas rau nruab. Thermocouples yog qhov kev xaiv zoo tshaj plaws rau siab heev -kub kev lag luam, RTDs yog qhov tseeb tshaj plaws nyob rau hauv kev tswj ib puag ncig, thermistor yog qhov kev xaiv zoo tshaj plaws rau nruab nrab ntawm tus nqi qis, thiab IC sensors ua kom yooj yim rau kev sib txuas hluav taws xob digitally. Infrared thiab fiber ntau optic yog ob qho piv txwv ntawm lwm hom uas ua rau nws muaj peev xwm los npog tag nrho cov kev lag luam, txawm tias cov tsis tuaj yeem ncav cuag los ntawm kev kov ncaj qha lossis EMI.
