PT100 (RTD) yog dab tsi-- Txoj Cai thiab kev siv ntawm 2-xov hlau, 3- hlau, thiab 4- hlau
RTDs - lossis Resistance Temperature Detectors - yog cov ntsuas kub hom sensors uas muaj cov resistor uas tuaj yeem sib txawv nrog qhov kub thiab txias. Nws tau siv rau hauv cov txheej txheem kev lag luam thiab cov chaw kuaj mob tau ntau xyoo nrog cov yam ntxwv meej, txhim khu kev qha, thiab ruaj khov.
Lub 2-wire system yog tus qauv yooj yim tshaj plaws hauv RTD. Qhov no yog ib qho kev sib txuas tsim, nrog rau ib qho hlau lead ntawm txhua qhov kawg ntawm RTD, uas txuas rau cov khoom siv saib xyuas. Thaum xam qhov kub thiab txias hloov, nws yog xam qhov kev hloov ntawm tus nqi kuj, tab sis tus nqi kuj muaj xws li ob tug leads uas yog resistors thiab cov cuab yeej ua hauj lwm RTD tiag tiag, yog li cov txiaj ntsig yuav muaj qee qhov sib txawv lossis yuam kev.
3-wire PT100
Nov yog qee yam uas ntau tus neeg tsis nkag siab, thiab nws kuj yog ib yam uas kuv tsis tau nkag siab thaum lub sijhawm. Lub 3-wire RTD yog feem ntau siv hauv kev tsim khoom thiab cov khoom siv saib xyuas. Qhov kev teeb tsa no muaj ob txoj hauv kev ntawm ib qho kawg ntawm RTD thiab tsuas yog ib qho txhuas ntawm lwm qhov kawg.
Hauv qhov tsim no, koj yuav tsum xyuas kom meej tias peb cov xov hlau siv R1, R2, thiab R3 yog ua los ntawm cov khoom siv tib yam, nrog qhov ntev thiab tuab. Qhov no txhais tau hais tias qhov kev tiv thaiv qhov tseem ceeb ntawm peb cov xov hlau yog tib yam.
3-wire PT100
Qhov tseeb, kev rho tawm tau ua nyob rau hauv cov cuab yeej saib xyuas: Rt1=R1+R2+Re
Rt2=R2+R3
Vim tias tag nrho peb cov xov hlau zoo ib yam: R1=R2=R3
Thaum kawg, hauv cov cuab yeej saib xyuas, Rt=Rt1-Rt2=Re tau txais
Tus nqi tiv thaiv ntsuas nyob rau hauv txoj kev no yog qhov kev tiv thaiv tus nqi ntawm Re hloov, uas yog twb muaj tseeb heev thiab tsis kim. Nws yog qhov ua tau zoo heev hauv kev lag luam.
