Munyaya yekushanda kwemaindasitiri otomatiki uye kudzora mashandiro, kubuda kwe4 - 20mA inzira inonyanya kukosha uye yakakosha yekutumira masaini eanalog. Kunzwisisa misimboti yayo, maficha ayo, uye mashandisirwo ayo kwakakosha kune nyanzvi muminda iyi, pamwe chete nechero ani zvake anofarira mashandiro akaomarara emasisitimu emazuva ano emaindasitiri.
Kubuda kwe4 - 20mA kunoreva sisitimu yemagetsi inotenderera uko chiratidzo chinomiririrwa nemagetsi anotenderera zvakananga (DC) anosiyana mukati me4 milliamperes (mA) kusvika 20mA. Pano, "mA" inomiririra milliamperes, unit yemagetsi anotenderera. Musisitimu iyi, 4mA inowanzo miririra zero kana kukosha kwechinhu chakayerwa, nepo 20mA inoenderana nehukuru hwepamusoro. Semuenzaniso, mukushandiswa kwekuona tembiricha, 4mA inogona kuratidza tembiricha ye0 degrees Celsius, uye 20mA inogona kuratidza tembiricha ye100 degrees Celsius, zvichienderana nekugadziriswa kwesensor nesisitimu.
Nheyo iri shure kwe4 - 20mA output iri mukukwanisa kwayo kutumira ruzivo kure kure neruzha rwemagetsi nekukanganiswa kwakaderera. Kusiyana nemasaini eanalog akavakirwa pamagetsi, ayo anogona kukanganiswa nyore nyore nekuramba kuri muwaya dzekutumira uye kunze kwema electromagnetic fields, masaini emagetsi anochengetedza kusimba kwawo zviri nani. Izvi zvinodaro nekuti magetsi ari kuyerera nepachitenderedzo anoramba aripo pasinei nekuramba kuri muwaya, chero bedzi magetsi achigona kupa voltage yakakwana yekukunda kuramba kuri muchitenderedzo. Sensor iri kumagumo echitenderedzo, senge sensor yekumanikidza kana flow meter, inoshandura huwandu hwemuviri hwainoyera (pressure, flow, nezvimwewo) kuita magetsi ari mukati me4 - 20mA range. Iyi magetsi inobva yafamba nepakati pe wire circuit mbiri kana ina kuenda kumagumo ekugamuchira, uko inoshandurwa zvakare kuita chiratidzo chinoshandiswa, senge kuverenga pachiratidziro kana input ye control system.
Chimwe chezvakanakira zvakakosha zve 4 - 20mA output kugona kwayo kutsigira michina "inofambiswa ne "loop". Mukugadzirisa kwe "loop-powered", waya mbiri dzakafanana dzinotakura chiratidzo chemagetsi dzinopawo simba kune sensor kana transmitter. Izvi zvinoita kuti waya dzive nyore uye zvinoderedza mari yekuisa, kunyanya mumafekitori makuru emaindasitiri ane masensa nemidziyo yakawanda. Pamusoro pezvo, chiyero che 4 - 20mA chinoita kuti zvive nyore kuona zvikanganiso musystem. Sezvo 0mA isiri chikamu cheyakajairika yekushanda (yakaderera i4mA), kuverenga kwe 0mA kana current iri kunze kwe4 - 20mA range kunowanzo ratidza dambudziko, senge waya yakatyoka, sensor isiri kushanda zvakanaka, kana dambudziko nemagetsi.
Kubuda kwe4 - 20mA kunoshandiswa zvakanyanya mumaindasitiri akasiyana-siyana. Muindasitiri yemafuta negesi, inoshandiswa kutumira data kubva kumasensa ekutarisa maparamita akadai sekumanikidzwa kwepaipi, mwero wekuyerera kwemvura, uye huwandu hwetangi kuenda kumakamuri ekudzora epakati. Mumafekitori ekugadzira, inobatsira mukudzora nekutarisa maitiro akadai sekupisa, hunyoro, uye kuwanda kwemakemikari mumareactor. Muchikamu cheotomatiki yekuvaka, masaini e4 - 20mA anoshandiswa kubata masisitimu ekudziyisa, kufefetera, uye air-conditioning (HVAC), kugadzirisa maparamita zvichienderana nekuverengwa kwemasensa ezvakatipoteredza.
Mukupedzisa, kubuda kwe4 - 20mA inzira yakakosha uye yakavimbika yekutumira masaini eanalog munzvimbo dzemaindasitiri uye dzekutonga. Kusimba kwayo pakurwisa ruzha, rutsigiro rwezvishandiso zvinofamba-famba, uye nyore kuona zvikanganiso zvakaita kuti ive sarudzo inofarirwa kune akawanda mashandisirwo, zvichiita kuti mashandiro akanaka uye kutonga kwakanaka kwemasisitimu emaindasitiri pasi rese. Sezvo tekinoroji ichiramba ichichinja, chiyero che4 - 20mA chinogona kubatanidzwa nemapuroteni matsva ekutaurirana edhijitari, asi kukosha kwayo munzvimbo yeanalog-based industrial automation kuchiri kusimbiswa.
Nguva yekutumira: Kubvumbi-30-2025