Porotokole ya RS485/ModBus-RTU ni iki?

Uburyo bwo gutumanaho bwa RS485 ni uburyo bukoreshwa cyane mu bijyanye noingandan'ikoranabuhanga ry'ubucuruzi rikoreshwa mu itumanaho ry'uruhererekane. Byakozwe kugira ngo bikemure imbogamizi z'amahame y'itumanaho ry'uruhererekane yabanje no gutuma amakuru yoherezwa mu ntera ndende no mu bihe bigoye kurushaho.

• Ibimenyetso by'amashanyarazi
  • RS485 ikoresha ibimenyetso bitandukanya. Aho gukoresha insinga imwe yo kohereza amakuru nk'uko bigenda mu zindi mbuga (nka RS232), ifite insinga ebyiri, akenshi zanditseho A na B. Itandukaniro ry'amashanyarazi hagati y'izi nsinga ebyiri rigaragaza amakuru. Itandukaniro ry'amashanyarazi hagati y'insinga A na B (urugero, A - B > 0.2 V) risobanurwa nka logique 1, mu gihe itandukaniro ry'amashanyarazi mabi (A - B < - 0.2 V) rigaragaza logique 0. Ubu buryo bwo kugaragaza ibimenyetso bitandukanya butanga ubudahangarwa bwiza bw'urusaku. Mu nganda zikora urusaku, aho amashanyarazi akunze kugaragara, itandukaniro ry'amashanyarazi hagati y'insinga ebyiri ntirishobora kugira ingaruka ku rusaku rwo hanze ugereranije na sisitemu imwe y'ibimenyetso.
• Ubushobozi bwo kugabanya ibintu byinshi
  • Kimwe mu bintu by'ingenzi biranga RS485 ni imikorere yayo yo guterera ibintu byinshi. Bus imwe ya RS485 ishobora kwakira nodes zigera kuri 32 (ibikoresho). Hari transceivers za RS485 zigezweho zishobora no gufata nodes nyinshi, kugeza kuri 256 mu bihe bimwe na bimwe. Ibi bituma ibikoresho byinshi, nka sensors, actuators, na controllers, bihuzwa na bisi imwe y'itumanaho. Urugero, muri sisitemu y'ubwikorezi bw'inyubako, sensors nyinshi z'ubushyuhe, sensors z'ubushuhe, na controllers z'amatara zose zishobora guhuzwa na bisi imwe ya RS485, bigabanya uburyohe bwo guhuza insinga n'imiterere ya sisitemu.
• Intera yo kohereza ubutumwa
  • RS485ishobora kugera ku ntera ndende yo kohereza amakuru. Mu bihe byiza, hamwe n'umuvuduko w'amakuru ugera kuri 9600 bps, ishobora kohereza amakuru mu ntera igera kuri metero 1200. Uko umuvuduko w'amakuru wiyongera, ni ko intera ntarengwa yo kohereza amakuru igabanuka. Urugero, ku muvuduko w'amakuru wa 1 Mbps, intera ntarengwa ikunze kuba metero 100. Ubu bushobozi bw'intera ndende butuma ikoreshwa aho ibikoresho bikwirakwijwe ahantu hanini, nko mu nganda, imiyoboro y'amashanyarazi, na sisitemu z'umutekano.

• Igice cya kabiri cy'imikorere ya Duplex
  • RS485 ahanini ni igice cy’itumanaho rya kabiri. Ibi bivuze ko amakuru ashobora koherezwa mu cyerekezo icyo ari cyo cyose, ariko atari icyarimwe. Igikoresho kimwe gusa kiri muri bisi gishobora kohereza amakuru icyarimwe, mu gihe ibindi bikoresho biri mu buryo bwo kwakira amakuru. Kugira ngo ibi bigenzurwe, hakenewe uburyo bwo kugenzura igikoresho gifite uburenganzira bwo kohereza amakuru. Ibi bikunze kugerwaho binyuze muri protocole aho ibikoresho bihabwa aderesi. Urugero, muri protocole ya Modbus RTU (Remote Terminal Unit), ikoreshwa cyane na RS485, igikoresho gikuru gitoranya ibikoresho by’abacakara mu kohereza ubusabe bufite aderesi yihariye y’umucakara ugenewe. Umucakara uhawe aderesi hanyuma arasubiza, kandi muri icyo gihe, ibindi bikoresho biguma mu buryo bwo kwakira amakuru.
• Guhuza Porotokole
  • RS485Ntabwo ari protocole ubwayo ahubwo itanga urwego rw'umubiri rwa protocole zitandukanye z'itumanaho. Uretse Modbus RTU, izindi protocole nka Profibus - DP (Process Field Bus - Decentralized Periphery) nazo zikoresha RS485 nk'uburyo bwo guhuza amakuru. Izi protocole zisobanura uburyo amakuru ashyirwa mu buryo, ashyirwa mu buryo, n'uburyo amakosa agenzurwa. Urugero, Modbus RTU ikoresha imiterere ya frame ifite uburebure buhamye hamwe na start and stop bits, kandi ikubiyemo kode yo kugenzura cyclic redundancy (CRC) ku mpera ya buri frame kugira ngo hamenyekane amakosa yo kohereza amakuru. Uku guhuza na protocole nyinshi bituma RS485 ikoreshwa cyane kandi ikoreshwa mu buryo butandukanye bw'inganda n'ubucuruzi.

• Ikoranabuhanga mu by'Ubwikorezi
  • Mu nganda, RS485 ikoreshwa mu guhuza ibyuma bigenzura imikorere (PLCs), ibyuma bihuza abantu n’imashini (HMIs), ibyuma bipima, n’ibikoresho bipima. Urugero, mu ruganda rukora, PLC zishobora kuvugana n’ibikoresho byinshi bipima (nk’ibikoresho bipima hafi, ibikoresho bipima umuvuduko) n’ibikoresho bipima (nk’ibikoresha moteri, valves) binyuze mu muyoboro wa RS485. Ibi bituma habaho kugenzura no gukurikirana inzira yo gukora, bigatuma habaho imikorere myiza no gusubiza vuba impinduka cyangwa amakosa iyo ari yo yose.
• Sisitemu zo gucunga inyubako
  • RS485 igira uruhare runini mu micungire y’inyubako. Ikoreshwa mu guhuza ibikoresho bitandukanye byikora ku nyubako, nko gushyushya, guhumeka, no gukonjesha (HVAC), uburyo bwo kugenzura amatara, na sisitemu z’umutekano. Urugero, umugenzuzi mukuru w’inyubako ashobora kuvugana n’ibikoresho byinshi bya HVAC binyuze muri RS485 kugira ngo ahindure ubushyuhe, ubushuhe, n’imiterere y’umwuka bitewe n’uko inyubako iba imeze n’ibidukikije.
• Imicungire y'amashanyarazi n'ingufu mu buryo bwa Smart Grid
  • Mu rwego rwa "smart grids", RS485 ikoreshwa mu guhuza "smart meter", "energy monitoring", n'ibikoresho byo gukwirakwiza ingufu. "Smart meter" ishobora kohereza amakuru akoreshwa n'amashanyarazi ahantu hakurura amakuru binyuze muri RS485. Aya makuru akoreshwa mu kwishyuza, gucunga imizigo, no kunoza grid. Byongeye kandi, RS485 ishobora gukoreshwa mu kugenzura no kugenzura ibikoresho byo gukosora ingufu n'ibindi bikoresho biri mu muyoboro w'amashanyarazi.