Me yasa 4-20mA?

Menene 4-20mA?

Ƙididdigar siginar 4-20mA DC (1-5V DC) ita ce Hukumar Kula da Fasaha ta Duniya (IEC) kuma ana amfani da ita don siginar analog a cikin tsarin sarrafa tsari.

Gabaɗaya, siginar siginar kayan aiki da mita an saita zuwa 4-20mA, tare da 4mA yana wakiltar mafi ƙarancin halin yanzu da 20mA yana wakiltar matsakaicin halin yanzu.

Me yasa fitarwa na yanzu?

A cikin saitunan masana'antu, yin amfani da amplifier sigina zuwa yanayi da watsa sigina akan dogon nisa ta amfani da siginar lantarki na iya haifar da batutuwa da yawa.Na farko, siginar wutar lantarki da ake watsawa akan igiyoyi na iya zama mai saurin kamuwa da kutsewar amo.Na biyu, juriya da aka rarraba na layin watsawa na iya haifar da raguwar wutar lantarki.Na uku, samar da wutar lantarki ga siginar ƙararrawa a cikin filin na iya zama ƙalubale.

Don magance waɗannan batutuwa da rage tasirin amo, ana amfani da halin yanzu don isar da sigina saboda rashin kula da surutu.Madauki na 4-20mA na yanzu yana amfani da 4mA don wakiltar siginar sifili da 20mA don wakiltar siginar cikakken sikelin, tare da sigina da ke ƙasa da 4mA da sama da 20mA da aka yi amfani da su don ƙararrawar kuskure daban-daban.

Me yasa muke amfani da 4-20mA DC (1-5V DC)?

Kayan aikin filin na iya aiwatar da tsarin wayoyi guda biyu, inda wutar lantarki da kaya ke haɗa su a jere tare da ma'ana guda ɗaya, kuma wayoyi biyu kawai ake amfani da su don sadarwar sigina da samar da wutar lantarki tsakanin mai watsa filin da kayan aikin dakin sarrafawa.Yin amfani da siginar 4mA DC kamar yadda lokacin farawa yana samar da tsayayyen aiki na yanzu zuwa mai watsawa, da saita ma'aunin sifilin lantarki a 4mA DC, wanda bai dace da ma'aunin sifilin injin ba, yana ba da damar gano kurakuran kamar asarar wutar lantarki da kebul na karya. .Bugu da ƙari, tsarin wayoyi biyu ya dace don amfani da shingen tsaro, yana taimakawa wajen kare fashewa.

Kayan aikin dakin sarrafawa suna amfani da watsa siginar lantarki-daidaitacce, inda kayan aikin da ke cikin tsarin sarrafawa iri ɗaya suke raba tashoshi gama gari, yana sa ya dace don gwajin kayan aiki, daidaitawa, mu'amalar kwamfuta, da na'urorin ƙararrawa.

Dalilin yin amfani da 4-20mA DC don sadarwar sigina tsakanin kayan aikin filin da kayan aikin ɗakin kulawa shine cewa nisa tsakanin filin da ɗakin kulawa na iya zama mahimmanci, yana haifar da juriya na USB.Ana isar da siginar wutar lantarki a kan nesa mai nisa na iya haifar da manyan kurakurai saboda raguwar ƙarfin lantarki da ke haifar da juriya na kebul da juriyar shigar da kayan aikin karɓa.Yin amfani da siginar tushe na yau da kullun don watsa nesa yana tabbatar da cewa na yanzu a cikin madauki ya kasance baya canzawa ba tare da la'akari da tsayin kebul ba, yana tabbatar da daidaiton watsawa.

Dalilin yin amfani da siginar 1-5V DC don haɗin kai tsakanin kayan aikin dakin sarrafawa shine don sauƙaƙe kayan aiki da yawa waɗanda ke karɓar sigina iri ɗaya da kuma taimakawa wajen yin waya da ƙirƙirar tsarin sarrafawa daban-daban.Idan aka yi amfani da tushen yanzu azaman siginar haɗin kai, lokacin da kayan aiki da yawa ke karɓar sigina iri ɗaya a lokaci guda, juriyar shigar su dole ne a haɗa su a jere.Wannan zai wuce ƙarfin nauyin kayan aikin watsawa, kuma siginar siginar ƙasa na kayan aikin karba zai bambanta, gabatar da tsangwama da hana samar da wutar lantarki ta tsakiya.

Amfani da siginar tushen wutar lantarki don haɗin kai yana buƙatar canza siginar da ake amfani da ita don sadarwa tare da kayan aikin filin zuwa siginar ƙarfin lantarki.Hanya mafi sauƙi ita ce haɗa daidaitaccen resistor 250-ohm a jere a cikin da'irar watsawa ta yanzu, tana jujjuya 4-20mA DC zuwa 1-5V DC.Yawanci, ana yin wannan aikin ta hanyar watsawa.

Wannan zane yana amfani da resistor 250-ohm don canza siginar 4-20mA na yanzu zuwa siginar ƙarfin lantarki na 1-5V, sannan yana amfani da matatar RC da diode mai haɗawa da fil ɗin juyawa na microcontroller's AD.

Anan haɗe da zane mai sauƙi don canza siginar 4-20mA na yanzu zuwa siginar wutar lantarki:

Me yasa aka zaɓi mai watsawa don amfani da siginar 4-20mA DC don watsawa?

1. Abubuwan la'akari da aminci ga mahalli masu haɗari: Tsaro a cikin mahalli masu haɗari, musamman don kayan aikin da ba su iya fashewa, yana buƙatar rage tsayin daka da ƙarfin ƙarfin da ake buƙata don ci gaba da aiki na kayan aiki.Masu watsawa waɗanda ke fitar da siginar daidaitaccen siginar 4-20mA DC yawanci suna amfani da wutar lantarki 24V DC.Amfani da wutar lantarki na DC ya fi girma saboda yana kawar da buƙatar manyan capacitors da inductor kuma yana mai da hankali kan rarrabawar capacitance da inductance na wayoyi masu haɗawa tsakanin na'urar watsawa da na'urar kula da dakin, wanda ya yi ƙasa da ƙarancin wutar lantarki na hydrogen gas.

2. Ana fifita watsawar tushen yanzu akan tushen wutar lantarki: A lokuta inda nisa tsakanin filin da dakin sarrafawa yana da yawa, yin amfani da siginar wutar lantarki don watsawa na iya haifar da manyan kurakurai saboda raguwar ƙarfin lantarki da ke haifar da juriya na kebul da shigarwar. juriya na kayan aiki mai karɓa.Yin amfani da siginar tushe na yanzu don watsa nesa yana tabbatar da cewa na yanzu a cikin madauki ya ci gaba da kasancewa akai-akai, ba tare da la'akari da tsayin kebul ba, don haka kiyaye daidaiton watsawa.

3. Zaɓin 20mA a matsayin matsakaicin halin yanzu: Zaɓin mafi girman halin yanzu na 20mA yana dogara ne akan la'akari da aminci, aiki, amfani da wutar lantarki, da farashi.Na'urorin da ke hana fashewa ba za su iya amfani da ƙarancin wutar lantarki da ƙarancin halin yanzu ba.4-20mA na yanzu da 24V DC suna da aminci don amfani a gaban iskar gas mai ƙonewa.Matsakaicin wutar lantarki na hydrogen gas tare da 24V DC shine 200mA, mahimmanci ya fi 20mA.Bugu da ƙari, ana la'akari da abubuwa kamar nisa tsakanin kayan aikin wurin samarwa, kaya, amfani da wutar lantarki, buƙatun kayan lantarki, da buƙatun samar da wutar lantarki.

4. Zaɓin 4mA a matsayin farawa na yanzu: Yawancin masu watsawa waɗanda ke fitar da 4-20mA suna aiki a cikin tsarin waya biyu, inda wutar lantarki da kaya ke haɗa su a jere tare da ma'ana guda ɗaya, kuma ana amfani da wayoyi biyu kawai don sadarwar sigina. da wutar lantarki tsakanin mai watsa filin da kayan aikin dakin sarrafawa.Zaɓin mai farawa na 4mA yana da mahimmanci don da'irar watsawa ta yi aiki.A 4mA farawa halin yanzu, ba daidai da na inji sifili batu, samar da "active sifili batu" cewa taimaka gano kurakurai kamar hasarar wutar lantarki da na USB karya.

Yin amfani da sigina na 4-20mA yana tabbatar da tsangwama, aminci, da aminci, yana mai da shi matsayin da aka yarda da shi sosai a aikace-aikacen masana'antu.Koyaya, wasu nau'ikan siginar fitarwa, kamar 3.33mV/V, 2mV/V, 0-5V, da 0-10V, ana kuma amfani da su don mafi kyawun sarrafa siginar firikwensin da tallafawa tsarin sarrafawa daban-daban.