Tau thiab RS485 feem ntau yog siv cov qauv kev sib txuas lus, thiab lawv tau siv dav hauv ntau cov kev lag luam tswj, kev siv tshuab, thiab teb chaws Automation. Ob txoj kev sib txuas lus sib txuas no tau pom zoo kom siv cov xov hlau Twisted- Cov xov hlau los xa cov paib. Hauv daim ntawv no, peb yuav tham txog vim li cas thiab RS485 tau pom zoo kom siv cov khoom siv sib luag thiab cov kev siv ntawm twisted- khub xaim.
I. theoretical ntsiab cai
1, anti - sib cuam tshuam muaj kev cuam tshuam
Tau thiab Rs485 yog ob qho kev sib txuas lus sib txuas lus, uas yuav tsum tau paub los ntawm cov kab sib kis kis thaum xa cov paib. Vim tias lub neej muaj ntawm ntau cov kev cuam tshuam nyob rau hauv kev cuam tshuam ntawm cov kev sib cuam tshuam hluav taws xob, ua rau muaj kev cuam tshuam hluav taws xob, ua rau cov teeb liab distortion, ber thiab lwm yam teeb meem.
Twisted - patter Cable muaj ob lub xov hlau yuav muab tso tawm ntawm cov teeb liab uas muaj kev cuam tshuam nrog lub teeb liab kev tawm tsam ntawm lub teeb liab - jamming muaj peev xwm.
2, kev quab yuam sib phim
Kev cuam tshuam sib txuam yog qhov teeb meem tseem ceeb heev hauv kev sib kis teeb liab. Yog hais tias lub impedance ntawm kis kab kis tsis sib phim, nws yuav ua rau muaj teeb meem xws li kev xav, foldback thiab distortion ntawm lub teeb liab. Cov duab saum toj no kuj qhia txog qhov tsis sib haum ntawm cov npav.
Lub impedance txuam kev ua tau zoo ntawm Twisted khub cable yog qhov zoo heev, uas tuaj yeem zam kev teeb meem xws li lub teeb liab xav thiab cov cim.
3, capacitance thiab inductance
Qhov kev muaj peev xwm thiab inductance ntawm cov kis tau yog qhov tseem ceeb uas cuam tshuam rau qhov zoo ntawm kev sib kis pom tau zoo. Qhov muaj peev xwm ntawm kis tau ntawm kis cov kab kis ua rau ncua thiab distortion ntawm lub teeb liab, thaum lub inductance txo cov teeb liab ntawm lub teeb liab. Cov qauv txheej txheem ntawm cov khub sib tw tuaj yeem txo cov hluav taws xob muaj peev xwm thiab kev tsis yeem ntawm cov kis tau tus kis, yog li ua kom muaj kev kis tau zoo thiab nrawm nrawm.
Ii. Kev xyaum ntawm daim ntawv thov
1, tuaj yeem thov nyiaj
Cov npav npav tuaj yeem sib txuas lus dav siv hauv kev tswj hwm kev tswj hwm thiab cov khoom siv hluav taws xob hauv tsheb thiab lwm thaj teb. Hauv npav, ob tog sib txuas lus sib txuas lus los ntawm ob khub ntawm cov xov hlau. Txij li thaum lub tsheb npav tuaj yeem ua haujlwm nrog ntau qhov kev cuam tshuam ntau hauv hluav taws xob thiab lub tsheb npav yuav tsum tau siv cov xov hlau kom ruaj khov thiab kev ntseeg tau ntawm cov cim kev kis tus kab mob.
2, RS485 Daim Ntawv Thov
Rs485 yog ib txoj kev sib txuas lus sib txuas lus dav siv hauv kev tswj ib yam, cov ntaub ntawv tau txais thiab cov teb thiab lwm yam teb. RS485 Kev Sib Txuas Lus Sib Txuas Lus tuaj yeem txhawb tau ntau- qhov deb ntawm cov ntaub ntawv kis, RS485 kuj yog qhov kev xaiv zoo heev.
Qhov laj thawj tseem ceeb rau RS485 los siv cov khub khub twisted yog txhawm rau txhim kho lub teeb liab thiab muaj peev xwm txo qhov kev sib cuam tshuam ntev dua thiab muaj kev sib txuas lus ruaj khov.
Ntxiv rau cov muaj peev xwm thiab Rs485, sib ntswg - Khub tau siv nyob rau hauv Ethernet, xov tooj, cov kab xov tooj cua. Ethernet yog thaj chaw sib txuas lus hauv zos sib txuas lus, thiab cov khoom siv sib luag ntawm cov khoom siv uas xav tau siab thiab kev sib txuas lus nrawm. Xov tooj thiab TV cables kuj yog tetted {{7} Khib khub cable tuaj yeem txhim kho cov khoom sib txuas zoo thiab kev ncua deb ntawm kev paub kev sib txuas lus zoo dua. Suab Cable kuj tseem siv tau sib piv khub, tuaj yeem txo cov teeb meem hluav taws xob hluav taws xob thiab suab nrov ntawm cov teeb liab suab.
Lub ntsiab
Twisted - khub cable yog ib qho kev ua tau zoo tshaj plaws uas muaj peev xwm tiv thaiv, kev cuam tshuam nrog cov peev txheej, kev sib txuam nrog thiab muaj peev xwm capitality. Nyob rau hauv tuaj yeem, RS485 thiab lwm txoj kev sib txuas lus, kev siv cov xov hlau txuas ntxiv tuaj yeem txhim kho kev sib txuas lus zoo thiab kev sib txuas lus ruaj khov thiab txhim khu kev qha. Hauv cov kev siv tswv yim, haum twisted- Khub yuav tsum tau raug xaiv raws li qhov kev xav tau thiab kev ua tau zoo thiab cov nyhuv {ua khub cable.