Cov Khoom Siv Hluav Taws Xob Hluav Taws Xob Siv Hluav Taws Xob Hluav Taws Xob Siv Hluav Taws Xob
Gas sensors tuaj yeem muab faib ua peb pawg loj raws li lawv cov hauv paus ntsiab lus:
Gas sensors siv lub cev thiab tshuaj lom neeg, xws li semiconductor raws li (sov tswj, ntim tswj, nto peev xwm raws li), catalytic combustion raws li, khoom thermal conductivity raws li, thiab lwm yam. Gas sensors siv lub cev muaj zog xws li thermal conductivity, optical cuam tshuam, infrared absorption. , thiab lwm yam. Gas sensors siv cov khoom siv hluav taws xob, xws li lub peev xwm tsis tu ncua electrolysis, galvanic cell, diaphragm ion electrode, tsau electrolyte, thiab lwm yam. Raws li cov kev phom sij, peb faib cov pa phem thiab cov pa phem rau hauv ob pawg: cov pa roj carbon monoxide thiab cov pa phem. Vim lawv cov khoom sib txawv thiab kev phom sij, lawv txoj kev tshawb nrhiav kuj sib txawv.
Combustible gases yog cov pa phem tshaj plaws uas tau ntsib nyob rau hauv kev lag luam chaw xws li petrochemicals. Lawv feem ntau yog cov pa roj carbon monoxide xws li alkanes thiab qee cov roj inorganic xws li carbon monoxide. Kev tawg ntawm combustible gases yuav tsum tau raws li tej yam kev mob, uas yog: ib tug tej yam concentration ntawm combustible gases, ib tug npaum li cas ntawm cov pa oxygen, thiab ib qhov chaw ntawm hluav taws kub txaus rau ignite lawv, ib tug humidity sensor sojntsuam, stainless hlau hluav taws xob cua sov raj, PT100 sensor, kua solenoid valve, cam khwb cia txhuas rhaub, thiab cua sov coil. Cov no yog peb lub ntsiab ntawm kev tawg (raws li qhia hauv daim duab peb sab tawg hauv daim duab sab laug saum toj), uas yog qhov tseem ceeb. Hauv lwm lo lus, qhov tsis muaj ib qho ntawm cov xwm txheej no yuav tsis ua rau hluav taws kub lossis tawg. Thaum cov roj hluav taws xob (steam, plua plav) thiab cov pa oxygen sib xyaw thiab ncav cuag ib qho concentration, lawv yuav tawg thaum raug hluav taws kub nrog qee qhov kub. Peb xa mus rau qhov concentration ntawm cov roj combustible tawg thaum raug hluav taws kub raws li qhov kev txwv ntawm qhov tawg, luv luv li qhov txwv tsis pub tawg, uas feem ntau qhia hauv%.
Qhov tseeb, qhov sib xyaw no tsis tas yuav tawg ntawm qhov sib tov sib xyaw thiab yuav tsum muaj qhov sib txawv. Qhov chaw ntxoov ntxoo qhia hauv daim duab ntawm sab xis saum toj no. Thaum lub concentration ntawm cov roj combustible qis dua LEL (* tsawg explosive limit) (tsis txaus combustible gas concentration) thiab saum toj no UEL (* siab explosive limit) (tsis txaus oxygen), tsis muaj tawg yuav tshwm sim. Lub LEL thiab UEL ntawm cov roj hluav taws xob sib txawv sib txawv (saib cov lus qhia hauv qhov teeb meem thib yim), uas yuav tsum tau coj mus rau hauv tus account thaum ntsuas ntsuas ntsuas. Rau lub hom phiaj ntawm * *, peb yuav tsum feem ntau tshaj tawm lub tswb thaum lub concentration ntawm combustible gas nyob rau ntawm 10% thiab 20% ntawm LEL, qhov twg 10% LEL raug xa mus rau. Ua kev ceeb toom ceeb toom, thaum 20% LEL hu ua kev ceeb toom txaus ntshai. Yog vim li cas peb hu lub combustible gas detector LEL detector. Nws yuav tsum tau muab sau tseg tias 100% tso tawm nyob rau hauv lub LEL detector tsis qhia hais tias cov concentration ntawm combustible gas ncav cuag 100% ntawm cov roj ntim, tab sis mus txog 100% ntawm LEL, uas yog sib npaug rau qhov tsawg explosive txwv ntawm combustible gas. Yog tias nws yog methane, 100% LEL=4% ntim concentration (VOL). Hauv kev ua haujlwm, tus ntes uas ntsuas cov pa roj hauv LEL hom yog cov khoom siv catalytic combustion detector.
Nws lub hauv paus ntsiab lus yog ob txoj kev choj (feem ntau hu ua Wheatstone choj) nrhiav kom pom. Cov khoom siv catalytic combustion yog coated ntawm ib qho ntawm cov platinum hlau txuas hniav. Tsis muaj teeb meem dab tsi ntawm cov roj hluav taws xob, tsuav yog nws tuaj yeem raug hluav taws xob los ntawm electrode, qhov kev tiv thaiv ntawm platinum hlau choj yuav hloov vim qhov kub thiab txias. Qhov kev hloov pauv tsis haum no yog proportional rau qhov concentration ntawm cov pa taws. Qhov concentration ntawm cov roj hluav taws xob tuaj yeem raug xam los ntawm lub tshuab hluav taws xob thiab microprocessor ntawm qhov ntsuas.
