Kulankhulana kwa Modbus: Chinsinsi Chomangira Maukonde Opanda Zovuta a Mafakitale
Kulankhulana kwa Modbus: Chinsinsi Chomangira Maukonde Opanda Zovuta a Mafakitale
Chidule
Modbus ndi njira yodziwika bwino yogwiritsira ntchito m'mafakitale, yomwe idapangidwa mu 1979 kuti ithandize kulumikizana pakati pa zida zodziyimira pawokha. Modbus idakhazikitsidwa poyamba ngati njira yogwiritsira ntchito potumiza deta kudzera mu serial layer, ndipo tsopano ikhozanso kukulitsidwa kuti igwiritsidwe ntchito kudzera mu serial, TCP/IP, ndi User Datagram Protocol (UDP). Chikalatachi chimapereka kutanthauzira kozama kwa momwe protocol imagwiritsidwira ntchito.
Kodi ndondomeko ya Modbus ndi chiyani?
Modbus ndi njira yoyankhira pempho yomwe imachitika kudzera mu ubale wa mbuye ndi kapolo. Mu ubale wa mbuye ndi kapolo, kulankhulana kumachitika nthawi zonse m'magulu awiriawiri (chipangizo chiyenera kuyambitsa pempho kenako n'kudikira yankho), ndipo chipangizo chopempha (chipangizo chachikulu) chimakhala ndi udindo woyambitsa kuyanjana kulikonse. Kawirikawiri, chipangizo chachikulu ndi mawonekedwe a munthu ndi makina (HMI) kapena dongosolo lowunikira ndi kupeza deta (SCADA), pomwe zipangizo zina zimakhala masensa, owongolera malingaliro omwe angakonzedwe (plcs), kapena ma programmable automation controllers (PACs). Zomwe zili mu zopempha ndi mayankho awa, komanso netiweki yomwe imatumiza mauthenga awa, zimafotokozedwa ndi zigawo zosiyanasiyana za protocol.
Ndi zipangizo ziti zomwe zimathandiza protocol ya Modbus?
Njira ya Modbus imathandizidwa kwambiri ndi zipangizo, kuphatikizapo ma programmable logic controllers (PLCs), ma remote terminal units (RTUs), masensa, ma actuator, ma human-machine interfaces (HMIs), ndi mitundu ina yambiri ya zipangizo mu mafakitale automation ndi mafakitale. Dipatimenti Yoyang'anira Njira. Modbus imagwiritsidwa ntchito kwambiri ndipo yakhala muyezo weniweni wa mgwirizano pakati pa zipangizo zopangidwa ndi opanga osiyanasiyana m'magawo monga kupanga, mphamvu, mayendedwe, ndi zomangamanga zokha.
Chipata cha Modbus ndi chipangizo chomwe chimasintha njira yolumikizirana yomwe imagwiritsidwa ntchito ndi ma hub a netiweki yamachitidwe odziyimira pawokha. Chimalumikizana ndi zida zanzeru, chimasonkhanitsa deta kuchokera kuzipangizo zotsika ndikutumiza ku chipata cha Modbus, chimakhazikitsa kulumikizana ndi netiweki yapamwamba yamakompyuta, ndikuchita njira ya Modbus ndi makompyuta apa netiweki.
Njira yolumikizirana ya Modbus
Njira ya Modbus ili ndi njira zitatu zazikulu zolumikizirana:
lRTU (Chipinda Cholumikizira Kutali)
lASCII (American Standard Code for Information Interchange)
lTCP/IP (Transmission Control Protocol/Internet Protocol)
Mu protocol ya Modbus, Modbus TCP ndi Modbus RTU ndi njira ziwiri zolankhulirana zomwe zimagwiritsidwa ntchito kwambiri. Ngakhale kuti zonse zimapangidwa kuti zithandize kusinthana deta pakati pa zipangizo, pali kusiyana kwakukulu pa njira zawo zogwiritsira ntchito ndi zochitika za ntchito.
Njira yolumikizirana ndi liwiro
Modbus TCP imagwiritsa ntchito TCP/IP protocol stack potumiza deta kudzera pa ma network, kudalira zomangamanga za ma network monga Ethernet kuti ikwaniritse kutumiza deta mwachangu komanso kwakukulu.
Kumbali inayi, Modbus RTU imatumiza deta kudzera mu mizere yotsatizana monga RS-485 ndi RS-232, zomwe zimakhala ndi liwiro lochepa kwambiri lotumizira deta..
Modbus RTU imaphatikiza mafelemu a data mu mtundu wa binary, kuphatikiza ma adilesi, ma code a ntchito, deta, ndi ma checksum. Mtundu uwu umatumizidwa bwino mu mawonekedwe a binary, zomwe zimapangitsa kuti ukhale woyenera kwambiri pa ntchito zowongolera nthawi yeniyeni kapena zakomweko, makamaka m'malo opanda zomangamanga za netiweki zomwe zilipo, monga malo ogwiritsira ntchito mafakitale, makina ophatikizidwa, ma network a masensa, ndi makina ang'onoang'ono owongolera.
Kumbali inayi, Modbus TCP imasintha byte iliyonse ya deta ya binary kukhala chingwe chokhazikika cha manambala awiri a hexadecimal, chomwe chimalumikizidwa pamodzi ndikutumizidwa mu mtundu wa TCP code. Chifukwa cha kuphweka kwake, kudalirika, komanso kugwiritsa ntchito bwino ndalama, imagwiritsidwa ntchito kwambiri mumakina akuluakulu odziyimira pawokha, malo osungira deta, makina odziyimira pawokha, ndi intaneti yazinthu zamafakitale, zomwe zimafuna mtunda wautali wolumikizirana komanso zofunikira kwambiri nthawi yeniyeni komanso kukhazikika kuti deta ifalitsidwe.
Amalo ogwiritsira ntchito
Mu makampani opanga zinthu, Modbus imagwiritsidwa ntchito kulumikiza zida zosiyanasiyana zopangira ndikupeza kuwunika ndi kuwongolera njira zopangira nthawi yeniyeni; Mu gawo la mphamvu, imagwiritsidwa ntchito poyang'anira makina amagetsi, kuphatikiza njira zopangira magetsi, kutumiza, ndi kugawa; Mu makampani oyendera, Modbus imagwiritsidwa ntchito pamakina oyendera njanji m'mizinda, kuwunika momwe magalimoto alili, ndi zina zotero; Mu gawo la makina oyendetsera nyumba, Modbus imagwiritsidwa ntchito pamakina a HVAC, magetsi, ndi chitetezo m'nyumba.
Ndi chitukuko cha ukadaulo wa intaneti ya mafakitale ndi intaneti ya zinthu, Modbus ikupitilizabe kupanga zatsopano ndikusintha kuti igwirizane ndi zochitika zovuta komanso zosintha zamafakitale. Mwachitsanzo, Modbus/TCP pang'onopang'ono ikukhala muyezo wodziwika bwino wa kulumikizana kwa Ethernet yamafakitale, ndipo zida zolowera kutengera Modbus zimathandiza zida zachikhalidwe za Modbus kulumikizana mosavuta ndi ma netiweki amakono, zomwe zimathandiza kusungira ndi kusanthula deta mumtambo.
Mwachidule, Modbus, monga njira yolankhulirana yokhwima komanso yogwiritsidwa ntchito kwambiri m'mafakitale, yawona kupita patsogolo kwa ukadaulo wodziyimira pawokha wamafakitale ndipo yakhazikitsa maziko olimba a luntha lamtsogolo la mafakitale. Ndi chitukuko chopitilira chaukadaulo, Modbus ipitiliza kuchita gawo lofunikira pakuyendetsa zatsopano ndi kusintha m'gulu la mafakitale.kapena.