Ntau tus kws tshaj lij tau tshaj tawm tias RS485 kev sib txuas lus hauv cov ntsuas hluav taws xob tuaj yeem qee zaum tsis sau cov ntaub ntawv, xav tau ntau qhov kev sim. Qhov teeb meem no tej zaum yuav muaj feem xyuam rau qhov tsis txaus electromagnetic compatibility (EMC) tsim.
EMC: Tus Saib Xyuas Tsis Pom Kev ntawm Kev Sib Txuas Lus
EMC (electromagnetic compatibility) yog hais txog lub peev xwm ntawm lub cuab yeej lossis lub cev ua haujlwm ib txwm nyob hauv nws qhov chaw electromagnetic yam tsis ua rau muaj kev cuam tshuam tsis zoo ntawm electromagnetic cuam tshuam rau lwm yam khoom siv hauv ib puag ncig.
EMC yog qhov tseem ceeb rau cov khoom siv xws lihluav taws xob meters. Nws tsis yog tsuas yog ib qho tseem ceeb uas yuav tsum tau ua kom tau raws li lub teb chaws cov kev cai thiab cov ntaub ntawv pov thawj kev lag luam (xws li CE, FCC, thiab 3C), tab sis kuj tseem ceeb heev rau kev ua kom ruaj khov thiab txhim khu kev qha cov khoom lag luam hauv cov khoom siv hluav taws xob thiab kev tiv thaiv kev nyab xeeb.
Cov teeb meem tshwm sim hauv RS485 Kev Sib Txuas Lus
Cov teeb meem cuam tshuam feem ntau hauv RS485 kev sib txuas lus rau lub zog ntsuas feem ntau yog los ntawm cov hauv qab no:
- Sab nrauv electromagnetic cuam tshuam: Lub zog ntsuas hluav taws xob feem ntau tau teeb tsa hauv qhov chaw muaj kev lag luam nyuaj, muaj feem cuam tshuam rau qhov cuam tshuam xws li inverters thiab lub cev muaj zog pib. Cov suab nrov no tuaj yeem ua ke rau hauv cov kab sib txuas lus.
- Cov kab hluav taws xob tsis zoo: Siv cov khoom tsis sib xws -pair cables, ungrounded shields, thiab parallel wire wiring with high-voltage lines can reduce the system's interference resistance.
- Surges surges: xob laim los yog kev ua haujlwm overvoltages tuaj yeem qhia txog kev nce siab. RS485 transceivers ua haujlwm ntawm qhov tsis tshua muaj hluav taws xob (nyob ib puag ncig 5V) thiab muaj qhov tsis tshua muaj hluav taws xob tsawg (-7V rau +12V). Overvoltages tuaj yeem ua rau lawv puas tsuaj.
Tus kheej- kuaj mob ntawm RS485 teeb meem kev sib txuas lus nrog cov ntsuas hluav taws xob
Txheeb xyuas cov kab hluav taws xob: Koj puas siv cov ntaub thaiv npog sib tw-pair cable? Puas yog daim thaiv npog ruaj khov rau hauv av ntawm ib kawg?
Puas muaj kev sib tw -pair cable ua haujlwm nrog RS485? Tsis yog! Ua ntej, koj yuav tsum siv lub twisted -pair cable nrog ib daim ntaub thaiv npog. Cov ntaub thaiv npog no ua raws li "lub tsho tiv thaiv mos txwv" rau lub teeb liab. Qhov tseem ceeb tshaj plaws, lub tsho tiv no "bulletproof" yuav tsum yog hauv av. Muaj ntau qhov kev ua txhaum tshwm sim vim tias daim ntaub thaiv yog sab laug dai xoob, lossis tsuas yog me ntsis compressed, tsis tau txuas nrog hauv av. Qhov no ua tau zoo tsim lub tsho tiv thaiv ib ncig ntawm lub teeb liab, tso cai rau kev cuam tshuam rau kev nkag mus. Nco ntsoov, ib daim ntaub thaiv npog tsis sib npaug yog tsis muaj kev tiv thaiv.
Tshawb xyuas hauv av: Puas yog cov digital thiab cov ntaub thaiv npog sib cais? Cov cuab yeej casing puas yog av?
Hauv av tsis yog ib qho teeb meem ntawm kev txuas lawv ua ke. Nws yog qhov zoo tshaj plaws los cais cov av digital (chip hauv av) thiab cov av analog (cov ntaub thaiv npog hauv av) kom tsis txhob muaj suab nrov ntawm cov digital circuit los ntawm kev khiav tawm hauv av xaim thiab cuam tshuam cov teeb liab analog. Qhov tseem ceeb tshaj, cov cuab yeej hlau casing yuav tsum muaj kev ntseeg siab hauv av. Qhov no ua rau muaj kev cuam tshuam tseem ceeb (xws li xob laim thiab hluav taws xob hloov pauv) hauv av es tsis tso cai rau lawv mus ncig hauv lub voj voog. Yog tias tsis muaj av zoo, txhua qhov kev tiv thaiv tsis muaj txiaj ntsig.
Kev Tiv Thaiv Kev Tiv Thaiv: Puas yog cov khoom tiv thaiv raug xaiv raug? Puas yog qhov kev txiav txim "kev tiv thaiv ua ntej, ces nti"?
Ntxiv cov kev tiv thaiv Circuit Court (xws li TVS diodes thiab cov pa roj tso tawm) rau RS485 interface yog qhov tsim nyog, tab sis kev teeb tsa ib leeg tsis lav qhov ua tau zoo. Cov khoom tiv thaiv no ua haujlwm nyob rau hauv hierarchical yam (ntau npaum li muaj kev ruaj ntseg thawj zaug thaiv tsheb, ces SWAT). Lawv yuav tsum raug xaiv raws li qhov xav tau cuam tshuam kev siv ntawm lub xaib. Tsis tas li ntawd, lawv cov txheej txheem yuav tsum ua raws li "kev tiv thaiv ua ntej, tom qab ntawd lim" kev txiav txim: cov cim yuav tsum dhau los ntawm cov khoom tiv thaiv ua ntej nkag mus rau koj lub nti.
Xaus
Electromagnetic cuam tshuam yog ubiquitous nyob rau hauv industrial ib puag ncig. Txawm hais tias RS485 kev sib txuas lus siv kev sib kis sib txawv, uas muab qee qhov kev cuam tshuam kev cuam tshuam, tsis ua haujlwm tseem ceeb ntawm EMC tsim hauv kev siv hluav taws xob ntsuas hluav taws xob tseem tuaj yeem ua rau muaj kev pheej hmoo ntawm kev sib txuas lus tsis ruaj khov, cov ntaub ntawv poob, thiab txawm tias cov khoom puas tsuaj.