Umusaruro wa 4 - 20mA ni iki?

Umusaruro wa 4 - 20mA yerekeza kuri sisitemu y'amashanyarazi aho ikimenyetso gihagarariwe n'amashanyarazi akoresha umuyoboro w'amashanyarazi (DC) uhinduka hagati ya milimetero 4 (mA) na 20mA. Aha, "mA" ihagarariye milimetero, igice cy'umuyoboro w'amashanyarazi. Muri iyi sisitemu, 4mA ihagarariye zeru cyangwa agaciro gato k'impinduka yapimwe, mu gihe 20mA ijyanye n'agaciro ntarengwa. Urugero, mu ikoreshwa ry'ubushyuhe, 4mA ishobora kwerekana ubushyuhe bwa dogere selisiyusi 0, naho 20mA ishobora kwerekana ubushyuhe bwa dogere selisiyusi 100, bitewe n'uburyo sensor na sisitemu bigenzurwa.​

Ihame ry’umusaruro wa 4 - 20mA riri mu bushobozi bwayo bwo kohereza amakuru mu ntera ndende hamwe n’urusaku rw’amashanyarazi n’ingaruka mbi. Bitandukanye n’ibimenyetso bya analog bishingiye ku muvuduko w’amashanyarazi, bishobora kwangizwa byoroshye n’ubudahangarwa mu nsinga zitwara amakuru no mu nsinga z’amashanyarazi zo hanze, ibimenyetso bya current-loop bikomeza ubusugire bwabyo neza. Ibi biterwa nuko umuvuduko unyura muri current ugumaho uko umuvuduko w’amashanyarazi waba umeze kose, igihe cyose umuriro ushobora gutanga volteji ihagije yo gutsinda ubudahangarwa buri muri current. Sensor iri ku mpera y’aho current ituruka, nka sensor y’umuvuduko w’amashanyarazi cyangwa icyuma gipima flow, ihindura ingano ifatika ipima (umuvuduko w’amashanyarazi, flow, nibindi) mu muvuduko w’amashanyarazi uri hagati ya 4 - 20mA. Uyu muvuduko unyura mu muvuduko w’insinga ebyiri cyangwa enye ukagera ku mpera yakira, aho usubizwamo ikimenyetso gikoreshwa, nko gusoma kuri ecran cyangwa kwinjira muri sisitemu yo kugenzura.​

Imwe mu nyungu zikomeye z'umusaruro wa 4 - 20mA ni ubushobozi bwayo bwo gushyigikira ibikoresho "bikoresha umugozi". Mu gushyiraho umugozi ukoresha umugozi, insinga ebyiri zimwe zitwara ikimenyetso cy'amashanyarazi nazo zitanga ingufu kuri sensor cyangwa transmitter. Ibi byoroshya insinga kandi bigabanya ikiguzi cyo kuyishyiraho, cyane cyane mu nganda nini zifite sensor n'ibikoresho byinshi. Byongeye kandi, amahame ya 4 - 20mA yemerera kumenya amakosa muri sisitemu byoroshye. Kubera ko 0mA atari igice cy'urwego rusanzwe rw'imikorere (nibura ni 4mA), igipimo cya 0mA cyangwa umuriro uri hanze y'urwego rwa 4 - 20mA akenshi bigaragaza ikibazo, nk'insinga yangiritse, sensor idakora neza, cyangwa ikibazo cy'amashanyarazi.​

Umusaruro wa 4 - 20mA ukoreshwa cyane mu nganda zitandukanye. Mu nganda za peteroli na gaze, ukoreshwa mu kohereza amakuru aturutse ku bipimo bigenzura ibikoresho nk'umuvuduko w'imiyoboro, umuvuduko w'amazi, n'urugero rw'ibigega bijya mu byumba bigenzura. Mu nganda zikora, ufasha mu kugenzura no gukurikirana ibikorwa nk'ubushyuhe, ubushuhe, n'ubwinshi bw'ibinyabutabire mu byuma bitanga ingufu. Mu rwego rwo kwihutisha inyubako, ibimenyetso bya 4 - 20mA bikoreshwa mu gucunga sisitemu zo gushyushya, guhumeka, no gukonjesha umwuka (HVAC), bihindura ibipimo hashingiwe ku bipimo by'ibikoresho bitanga ingufu.​

Muri make, umusaruro wa 4 - 20mA ni uburyo bw'ibanze kandi bwizewe bwo kohereza ibimenyetso bya analog mu nganda no mu bidukikije. Kuba ikora neza mu kurwanya urusaku, gushyigikira ibikoresho bikoresha umuyoboro, no koroshya kubona amakosa byatumye iba amahitamo meza ku bikorwa byinshi, bishimangira imikorere myiza no kugenzura neza sisitemu z'inganda ku isi yose. Uko ikoranabuhanga rikomeza gutera imbere, igipimo cya 4 - 20mA gishobora guhuzwa na porogaramu nshya z'itumanaho rya digitale, ariko akamaro kayo mu bijyanye no gukoresha ikoranabuhanga rishingiye kuri analog karacyakomeye.