安裝(zhuang)在使(shi)用時要(yao)安裝(zhuang)在現(xian)場設備(bei)的動(dong)力線(xian)上,從國(guo)外的行(xing)業(ye)動(dong)態及變(bian)送(song)器(qi)心(xin)片(pian)供求量(liang)即可略知(zhi)壹(yi)斑,如(ru)果系(xi)統是(shi)在(zai)環(huan)境(jing)較為惡(e)劣(lie)的工(gong)業(ye)現(xian)場長期使(shi)用,因(yin)此(ci)需(xu)考(kao)慮硬件(jian)系(xi)統工(gong)作(zuo)的安全性和(he)可靠(kao)性,根據(ju)需(xu)要(yao)還(hai)可將模(mo)擬(ni)量(liang)變換(huan)為數(shu)字量(liang)。傳感器(qi)和(he)變(bian)送器(qi)壹(yi)同構成(cheng)自(zi)動控(kong)制的監測信(xin)號(hao)源。不同的物理(li)量(liang)需(xu)要(yao)不同的傳感器(qi)和(he)相應的變(bian)送器(qi)。
電(dian)流變(bian)送(song)器(qi)的模(mo)塊實(shi)現(xian)了無源交(jiao)流(liu)隔(ge)離(li)傳感器(qi)信(xin)號(hao)變換(huan)為兩(liang)根連(lian)接(jie)線(xian)路發送的呈(cheng)線性比例的環(huan)路電(dian)流,二(er)線(xian)制(zhi)變送(song)器(qi)是(shi)輔(fu)助工(gong)作(zuo)電(dian)源的+24V端(duan)接變(bian)送(song)器(qi)正(zheng)端(duan),電(dian)源負端(duan)通過采樣(yang)電(dian)阻或(huo)電(dian)流表(biao)接(jie)變(bian)送器(qi)的負(fu)端(duan)。模擬(ni)地(di)與數(shu)字地(di)相互分開(kai),這樣可提(ti)高系(xi)統工(gong)作(zuo)的安全性。不易受寄(ji)生熱電(dian)偶(ou)和(he)沿(yan)電(dian)線電(dian)阻壓(ya)降(jiang)和(he)溫漂(piao)的影(ying)響,可用(yong)非(fei)常(chang)便(bian)宜(yi)的更(geng)細的導(dao)線。
應用
電(dian)流變(bian)送(song)器(qi)在(zai)單片(pian)機(ji)控(kong)制的許(xu)多應(ying)用場合,都(dou)要(yao)使(shi)用變(bian)送器(qi)來將單片(pian)機(ji)不能(neng)直接(jie)測(ce)量的信(xin)號(hao)轉換(huan)成(cheng)單片(pian)機(ji)可以(yi)處(chu)理(li)的電(dian)模擬(ni)信(xin)號(hao),如(ru)電(dian)流變(bian)送(song)器(qi),壓(ya)力變送器(qi)、溫度(du)變(bian)送器(qi)、流(liu)量(liang)變(bian)送器(qi)等(deng)。早期的變(bian)送器(qi)大(da)多(duo)為電(dian)壓(ya)輸出型(xing),即(ji)將測(ce)量信(xin)號(hao)轉換(huan)為0-5V電(dian)壓(ya)輸出,這是(shi)運放直(zhi)接輸(shu)出,信(xin)號(hao)功(gong)率<0.05W,通過模擬(ni)/數(shu)字轉換(huan)電(dian)路轉換(huan)數(shu)字信(xin)號(hao)供單片(pian)機(ji)讀(du)取(qu)、控(kong)制。
是(shi)將液位傳感器(qi)裏(li)的下部的水(shui)和(he)上部蒸(zheng)汽(qi)的冷(leng)凝水(shui)通過儀表(biao)管(guan)送(song)到變送(song)器(qi)的波紋管(guan)兩(liang)側(ce),以(yi)波紋管(guan)兩(liang)側(ce)的差(cha)壓(ya)帶動機(ji)械(xie)放(fang)大(da)裝(zhuang)置(zhi)用(yong)指(zhi)針(zhen)指(zhi)示水(shui)位(wei)的壹(yi)種(zhong)遠方(fang)儀(yi)表(biao)。當(dang)然(ran)還(hai)有(you)把(ba)電(dian)氣模(mo)擬(ni)量(liang)變換(huan)成(cheng)數(shu)字(zi)量的也(ye)可以(yi)叫(jiao)變(bian)送(song)器(qi)。以(yi)上只(zhi)是(shi)從(cong)概(gai)念上說明(ming)傳感器(qi)和(he)變(bian)送器(qi)的區(qu)別。
而(er)兩(liang)線(xian)制(zhi)電(dian)流輸(shu)出型(xing)電(dian)流變(bian)送(song)器(qi)以(yi)其具(ju)有(you)*的抗幹(gan)擾能(neng)力得(de)到了廣泛(fan)應(ying)用。