Dab tsi yog "PPM" thiab "LEL" hauv cov khoom siv roj
Peb feem ntau pom "PPM" thiab "LEL" cim rau ntawm lub ntsuas roj. Yog li "PPM" thiab "LEL" yog dab tsi? Tej zaum ntau tus neeg tsis paub meej. Hauv qab no, plaub hauv ib lub tshuab ntsuas roj yuav qhia lub ntsiab lus tshwj xeeb ntawm ob lo lus kom ntxaws.
PPM "yog qhov ntim tshwj xeeb. PPM" yog ib qho kev sawv cev ntawm kev daws teeb meem, qhov twg PPM sawv cev rau qhov chaw ib lab. Rau cov kev daws teeb meem: yog tias muaj 1/1000 milliliter ntawm solute hauv 1 liter ntawm aqueous tov, qhov concentration yog 1 PPM. Rau cov pa roj: Ib txoj hauv kev rau kev nthuav tawm cov concentration ntawm cov pa phem hauv cov huab cua puag ncig. Volume concentration sawv cev txoj kev: Lub ntim ntawm cov pa phem muaj nyob rau hauv ib lab ntim ntawm huab cua, hu ua PPM. Cov cuab yeej ntsuas roj feem ntau ntsuas cov roj concentration raws li qhov ntim concentration (PPM), tab sis raws li Suav cov cai, tshwj xeeb tshaj yog cov chaw tiv thaiv ib puag ncig, cov roj concentration yuav tsum tau qhia nyob rau hauv chav nyob ntawm huab hwm coj concentration. Peb lub teb chaws cov qauv thiab cov kev cai tseem siv cov chav concentration loj los sawv cev rau cov roj concentration. Nws yog tsim los siv lub hauv paus ntsiab lus uas cov conductivity ntawm ib co hlau oxide semiconductor cov ntaub ntawv hloov nrog cov muaj pes tsawg leeg ntawm ib puag ncig roj ntawm ib tug tej yam kub thiab txias.
LEL "hais txog qhov txwv tsis pub tawg. Qhov tsawg kawg nkaus ntawm cov roj hluav taws xob uas tuaj yeem tawg tau thaum raug hluav taws kub hnyiab hauv huab cua yog hu ua qhov kev txwv qis qis - hu ua feem pua LEL.
Tsau VOC Gas Detector
Qhov siab tshaj plaws ntawm cov roj hluav taws xob uas tuaj yeem tawg tau thaum raug hluav taws xob qhib hauv huab cua yog hu ua qhov kev txwv siab tawg - hu ua feem pua UEL. Yog li dab tsi yog qhov kev txwv qis dua? Qhov concentration ntawm combustible gases tsawg dhau los yog siab dhau, thiab nws tsis txaus ntshai. Nws tsuas yog kub hnyiab los yog tawg thaum nws sib tov nrog huab cua los ua ib qho kev sib tov los yog, ntau precisely, thaum nws ntsib oxygen los ua ib feem ntawm qhov sib tov. Cov tuam tsev muaj cai lij choj thiab cov kws tshaj lij tau soj ntsuam kev sib tsoo thiab tawg ntawm cov pa hluav taws xob tam sim no nrhiav pom, thiab tsim kom muaj kev txwv tawg rau cov roj hluav taws xob hauv qab qhov kev txwv qis dua. Cov ntsiab lus ntawm cov roj combustible nyob rau hauv qhov sib tov yog tsis txaus los ua combustion los yog tawg, thiab cov pa oxygen cov ntsiab lus nyob rau hauv cov sib tov saum toj no lub sab sauv txwv tsis txaus yuav ua rau combustion los yog tawg.
Tsis tas li ntawd, combustion thiab tawg ntawm combustible gas kuj muaj feem xyuam rau tej yam xws li roj siab, kub, thiab ignition zog. Qhov kev txwv tawg feem ntau yog qhia raws li qhov ntim feem pua ntawm cov concentration. Qhov txwv tawg yog ib lo lus dav dav rau qhov txwv qis thiab sab sauv tawg. Qhov concentration ntawm cov pa roj combustible nyob rau hauv cov huab cua tsuas yog tawg ntawm qhov qis thiab sab sauv txwv. Kev tawg yuav tsis tshwm sim hauv qab lossis siab dua qhov kev txwv qis dua.
Yog li ntawd, thaum ua kev ntsuas tawg, lub tswb ntsuas feem ntau yog teem rau hauv qab 25 feem pua LEL ntawm qhov txo qis qis. Kev ntsuas ntau ntawm ntau yam khoom siv hluav taws xob hluav taws xob yog 0-100 feem pua LEL. Cov khoom siv hluav taws xob ruaj khov feem ntau muaj ob lub tswb ceeb toom: 10 feem pua LEL yog thawj theem tswb, thiab 25 feem pua LEL yog lub tswb theem thib ob. Portable combustible gas detectors feem ntau muaj lub tswb taw tes: 25 feem pua LEL yog lub tswb taw tes.
