Qhov Profibus - dp (faib cov khoom lag luam) cov qauv kev yuav tsum tsis pom muaj tseeb, tseem ua rau tsis meej pem hauv kev tsis meej pem transusion. Txawm li cas los xij, ib qho tsis meej meej tsis tiv thaiv kev sib raug zoo los ntawm kev ua ib qho kev daws teeb meem zoo, nrog ntau dua 50 lab pab pawg thoob ntiaj teb. Raws li cov tshuab tshiab tau tso tawm, nws yog qhov tseem ceeb rau cov kws kho tshuab uas lawv siv yog tsim los ntawm cov qauv hloov kho ntawm profibus {}} DP qauv.
Profibus - dp (faib khoom siv) cov qauv)
Qhov nrawm dua, yooj yim - dp Txheem tshwm sim nyob rau xyoo 1993 los ntawm nws tus niam txiv txheem, ntau dua cov qauv (teb cov lus qhia cov lus). Profibus- DP Kuj muaj cov menyuam yau lossis cov khoom lag luam Manchester, ua rau cov khoom lag luam Manchester, ua rau muaj kev nyab xeeb rau cov chaw muaj kev phom sij. Txawm li cas los xij, Profibus {{6} dp tseem siv tau ntau cov qauv siv niaj hnub no, yoog raws, thiab tus nqi - ua hauj lwm zoo. Los ntawm kev tswj cov sensors thiab cov neeg ua yeeb yam hauv kev siv cov khoom siv kom sib txuas lus thiab ntau daim npav sib tw (masters - i}
Profibus - dp tuaj yeem sib txuas lus tshaj ntau cov xov xwm, suav nrog xaim hlau, fiber ntau ptics, thiab txawm huab cua hauv infrared customators. Txog rau hnub, txheej txheem feem ntau ntawm ISO / OSI qauv) rau Profibus {}}} peg cable siv Rs485 transceivers. Qhov no yog unsurpising muab RS485 lub siab- Ceev kev sib txuas lus thiab cov khoom sib txawv dhau ntawm cov khoom muaj nyob hauv ib puag ncig tsis muaj suab nrov. Ntau tus masters, xws li PLCS (programrictric controllers), tuaj yeem txuas mus txog 30 tus qhev ib ntu nyob rau hauv kab topology. Siv cov hub (sib txuas ntu) lossis rov qab ua dua (ntu ntu) tuaj yeem txuas ntxiv rau lub network rau 124 qhev. Ntu yuav tsum tau txiav tawm ntawm ob qho kawg siv kev txiav tawm. Txhua tus qhev tuaj yeem kub -}}
95% RS485, 5% tsis meej pem
Profibus - DP adopts feem ntau ntawm cov tia / Eia {55-A Rs485-A Rs485-A Rs485-A Rs485-A Incorterently tau saib xyuas qhov kev txhawj xeeb ntau dua. Yog li ntawd, tsis sib xws rau kev ntseeg, tsis yog txhua tus RS485 kev hloov pauv thiab cov xaim haum rau cov nyiaj txiag profibus-dp network. Qhov sib txawv nyob hauv cov xaim, kev txiav tawm, cim npe, thiab cov kev xav tau; Kev hla dhau no tau yooj yim tshaj tawm txoj kev ua tau zoo (lossis loj zuj zus, kev pov thawj) ntawm koj tus tswv lossis qhev cuab yeej lossis qhev.
Thaum lub sijhawm RS485 tsis tau hais txog cov kev yuav tsum tau muab txoj kev siv hluav taws xob, 120 {{}} ω shield twisted khub (STP) CABLE tau dhau los ua cov lus pom zoo. Txawm li cas los xij, Profibus - dp pom zoo rau 150-ω stp cable. Hmoov tsis zoo, 120 ω tsis tuaj yeem kwv yees rau 150 ω, thiab qhov sib txawv me me hauv cable impedance yeej siv ntau cov cab kuj. Profibus-DP kuj qhia meej tshaj plaws cable ntev, uas vam khom ntawm 10 kauj ruam "yog siv, xws li ntawm 1,6 kbits / s txog 100 m ntawm 12 mbits / s.
Ntawm chav kawm, sib txawv cable impedance yuav tsum ua rau kev txiav txim siab sib txawv. Txhawm rau txo cov cim kev reflections, RS485 kev txhim kho feem ntau siv ib qho kev tiv thaiv ib zaug, thaum profibus {}} ω tshem tawm network ntawm txhua qhov kawg. Tos, yog tias typo? Profibus-DP pom zoo rau 171 ω, yog li tsis hais tias kev tsis sib xws ntawm 150-ω tus yam ntxwv tsis haum ntawm cov kev pom zoo cable? Kiag li. Daim duab 1 piav qhia txog qhov sib txawv ntawm cov cable thiab kev txiav nyiaj rau cov profibus-dp piv rau Rs485. Koj tuaj yeem pom ob qho 390-depor bias resistors siv nrog 220-ω txiav tseg cov noob taus; Lub zog tiv thaiv yog 171 ω. Qhov no yog kom meej meej tsis muaj kev sib tw zoo meej rau 150-ω cable, uas ua rau me ntsis network damping. Tab sis tsis txhob txhawj xeeb, vim qhov no qhia tsuas yog ib lub me me pob lossis nce hauv lub teeb liab voltage ntawm lub cable tau kawg, kav ntev ob zaug tshaj tawm kev ncua.
Daim duab 1: Qhov sib txawv hauv cov xaim, kev txiav tawm, thiab cov haujlwm PIN ntawm RS485 thiab Profibus- dp network.
Yog tias cable / tshem tawm mismatches tsis txaus, qhov tsis txaus ntseeg, kev hloov tsheb npav ntawm Profibus Transcepers yuav tsum txuas ntxiv ua rau koj cov kev cia siab ntxiv. Tej zaum koj yuav tau pom cov npe pin thim rov qab siv hauv daim duab 1. Hauv cov khoom siv RS485? Txawm li cas los xij, cov qauv kev qhia tau piav qhia txog kev caij npav polarity nyob rau hauv xws li txoj kev uas pins b thiab ib tug yog thim rov qab. Vim li cas qhov tsis sib xws? Tus thawj Tia / Eia- 485-tus qauv tsis tau meej meej rau kev sib raug zoo rau kev sib raug zoo rau txoj kev, thaum lwm tus txhais lwm tus. Qhov no txhais tau li cas rau koj? Tshwj xeeb tshaj yog tias koj muaj ob qho RS485 thiab Profibus-DP tej yaam num, koj yuav tsum tau ua tib zoo saib thaum Mapping Transceiver npav Pins rau cov txuas.
Muab cov naj npawb ntawm cov kev hloov pauv uas twb muaj lawm, cov neeg tsav tsheb voltage (V_ (OD)) yog feem ntau- dp lub cev lub cev. RS485 Qhia Txog V_ (OD) ntawm kab A thiab B AS 1.5 rau 54 {}}} dp specifies v_ (od) li 4 txog 7 v Ncau {{- rau-ncov sib txawv, ntsuas ntawm qhov kawg ntawm cov cabinators ntawm ob qho kawg.
Ib qho kev ua txhaum cai tsis meej yog tias yog RS485 tus tsav tsheb tsim tawm tshaj li 2.1 {}} dp {}} dp lifinated network. Txawm li cas los xij, qhov no tsis yog qhov tseeb. Tus RS485 tsav lub zog yuav yog ntau dhau thiab tshaj li 7 {}}}}}}} dp txwv. Nco ntsoov tias txhua qhov kev hloov pauv " Txoj kev zoo tshaj plaws los xyuas kom meej Profibus-DP v_ (OD) Ua raws cai yog sim cov transceer.
Daim duab 2 qhia txog yuav sim li cas LTC2877 Rugged Profibus RS485 transce desulors rau simulate kev ua raws li cov profibus - dp lus qhia. LTC2877 kuj tau sim tag nrho nrog RS485 thauj kom ntseeg tau tias vod ua raws li cov qauv.
Daim duab 2: Kuaj lub LTC2877 expour voltage (vod) siv profibus {{2} dp load.
Kev tiv thaiv Profibus - dp
Lub tia / iaia {- 485 - Tus qauv kev yuav tsum muaj kev tiv thaiv nrov nrov, esd, hloov hluav taws xob rov qab), lossis surges. Thiaj li, transceiver manufacturers thiab cov tsim qauv yuav tsum ua kev tiv thaiv hluav taws xob ywj pheej. Thaum yuav tsum muaj kev sib txawv ntawm daim ntawv thov, qee transc2877 qhia hauv daim duab 3-xa kev tiv thaiv qib siab uas tau raws li txhua yam kev xav tau.
Txoj hlua khi / Eia {{{4 4}} 485- V. Txawm li cas los xij, uas tuaj yeem ua rau muaj kev puas tsuaj loj heev rau profibus- dp transceivers. Profibus muaj feem ntau siv nyob rau hauv 24V systems, uas tsis ntev "tus qauv" RS485 ntaus ntawv rau 24v tuaj yeem ua rau neeg tuag taus. Cov neeg tsim qauv yuav tsum tau txais tus txais nrog ib qho kev ncua ntev {17} {{{{{{{20 23} {{20 23} {{}} Txij li Profibus {{{}} dp transceivers yog zoo txoj kab kev tiv thaiv, lawv yuav tsum tiv thaiv lawv tus kheej tawm tsam ntau theem ntawm ESD Surges. Some PROFIBUS transceivers offer 15kV ESD protection on their bus pins when de-energized; Lwm cov khoom lag luam, xws li LTC2877, muab ± 26 26 26, 26, 26, 262}} Enter lossis energized, thiab hauv txhua hom kev ua haujlwm. Ib qho ntxiv, lub npav Pins muaj kev tiv thaiv tawm tsam tiv thaiv ± 52KV hauv av thaum tsis muaj zog.
Lwm daim ntawv ntawm hluav taws xob kev tawm tsam yog EFT, txhais tau los ntawm IEC 61000 {{{{{1 {{1 {{1 - 4 {{1 - 4 { Hom kev tawm tsam no feem ntau tshwm sim los ntawm kev sib tiv tauj hauv cov pob hluav taws xob hauv qhov chaw muaj hluav taws xob uas eleconnect inductive thauj khoom. They should ensure the selected transceiver meets the highest level of IEC 61000-4-4, Level 4, equivalent to 2 kV open-circuit voltage on the bus pins.
Tej zaum qhov kev hnyav tshaj plaws ntawm cov hluav taws xob sib tshooj yog qhov phais kom raug xa los ntawm cov xwm hauv daim ntawv ntawm xob laim. Yog li ntawd, nws yog unsurprising tias tej yam me me hloov kho Ics zoo li LTC2877 tsis muaj kev tiv thaiv kev tiv thaiv qhov ntau ntawm no. Hloov chaw, cov khoom tiv thaiv sab nraud, suav nrog tso, TVs LTC2877 tsis tuaj yeem tiv thaiv kev tawm tsam ib leeg, tab sis nws cov kev ntaus nqi nyem yooj yim ua rau nws muaj peev xwm nrhiav tau cov kev tiv thaiv no.