E+H水分析變送器產品特性一覽

壓力變(bian)送(song)器(qi)也稱(cheng)差變(bian)送(song)器(qi)，由測壓元件傳感器(qi)、模塊電(dian)(dian)路、顯(xian)示(shi)表頭(tou)、表殼和(he)過程(cheng)連(lian)接件等(deng)(deng)(deng)組成。它能(neng)將接收的氣體、液體等(deng)(deng)(deng)壓力信號轉變(bian)成標準的電(dian)(dian)流電(dian)(dian)壓信號，以供給指示(shi)報警儀、記(ji)錄儀、調節器(qi)等(deng)(deng)(deng)二次儀表進行測量、指示(shi)和(he)過程(cheng)調節。

壓(ya)(ya)(ya)(ya)力(li)(li)變送(song)器(qi)測量原(yuan)理是：流程壓(ya)(ya)(ya)(ya)力(li)(li)和參考壓(ya)(ya)(ya)(ya)力(li)(li)分別(bie)作 變送(song)器(qi)（圖10）用(yong)于(yu)(yu)集成硅(gui)壓(ya)(ya)(ya)(ya)力(li)(li)敏(min)感元件的(de)(de)兩端，其差壓(ya)(ya)(ya)(ya)使(shi)硅(gui)片變形(xing)（位移(yi)很(hen)小(xiao)，僅(jin)μm級），以(yi)使(shi)硅(gui)片上用(yong)半導(dao)體(ti)技(ji)術制成的(de)(de)全動態惠斯(si)登(deng)電(dian)(dian)橋在外部電(dian)(dian)流源驅動下輸(shu)出正(zheng)比(bi)于(yu)(yu)壓(ya)(ya)(ya)(ya)力(li)(li)的(de)(de)mV級電(dian)(dian)壓(ya)(ya)(ya)(ya)信(xin)(xin)號(hao)(hao)(hao)。由于(yu)(yu)硅(gui)材料的(de)(de)強(qiang)性(xing)(xing)，所以(yi)輸(shu)出信(xin)(xin)號(hao)(hao)(hao)的(de)(de)線(xian)性(xing)(xing)度(du)及變差指標均很(hen)高。工(gong)作時(shi)，壓(ya)(ya)(ya)(ya)力(li)(li)變送(song)器(qi)將被測物理量轉(zhuan)換成mV級的(de)(de)電(dian)(dian)壓(ya)(ya)(ya)(ya)信(xin)(xin)號(hao)(hao)(hao)，并(bing)送(song)往(wang)放(fang)大倍數很(hen)高而又可(ke)以(yi)互相(xiang)抵消溫度(du)漂(piao)移(yi)的(de)(de)差動式放(fang)大器(qi)。放(fang)大后(hou)的(de)(de)信(xin)(xin)號(hao)(hao)(hao)經電(dian)(dian)壓(ya)(ya)(ya)(ya)電(dian)(dian)流轉(zhuan)換變換成相(xiang)應的(de)(de)電(dian)(dian)流信(xin)(xin)號(hao)(hao)(hao)，再(zai)經過非線(xian)性(xing)(xing)校正(zheng)，最后(hou)產生與(yu)輸(shu)入壓(ya)(ya)(ya)(ya)力(li)(li)成線(xian)性(xing)(xing)對應關系的(de)(de)標準電(dian)(dian)流電(dian)(dian)壓(ya)(ya)(ya)(ya)信(xin)(xin)號(hao)(hao)(hao)。

軟件(jian)的(de)使(shi)用(yong)同樣(yang)十分簡(jian)單。操作(zuo)向導直觀明了，引導用(yong)戶逐(zhu)步(bu)完(wan)成儀表(biao)設置、功能安全(quan)測試和驗證測試，降低操作(zuo)錯誤的(de)發生幾率。使(shi)用(yong)移動設備和安全(quan)Bluetooth藍牙連接，通(tong)過app可以遠程控制變送(song)器。

熱(re)(re)電(dian)阻(zu)溫(wen)度變送器(qi)是由(you)基準單元、R/V轉(zhuan)換單元、線(xian)(xian)性(xing)電(dian)路、 變送器(qi)（圖11）反接(jie)保(bao)護(hu)、限流保(bao)護(hu)、V/I轉(zhuan)換單元等組(zu)成(cheng)。測溫(wen)熱(re)(re)電(dian)阻(zu)信(xin)號轉(zhuan)換放大后，再由(you)線(xian)(xian)性(xing)電(dian)路對溫(wen)度與(yu)電(dian)阻(zu)的(de)非(fei)線(xian)(xian)性(xing)關(guan)系(xi)(xi)進(jin)行補(bu)償，經(jing)V/I轉(zhuan)換電(dian)路后輸(shu)出一個與(yu)被(bei)測溫(wen)度成(cheng)線(xian)(xian)性(xing)關(guan)系(xi)(xi)的(de)4～20mA的(de)恒流信(xin)號。

一般磁性浮球的(de)(de)比重小于(yu)0.5，可(ke)漂于(yu)液(ye)面之上(shang)并沿測量(liang)導管上(shang)下(xia)(xia)移動。導管內(nei)裝有(you)測量(liang)元件(jian)，它(ta)可(ke)以在外磁作用下(xia)(xia)將被(bei)測液(ye)位信(xin)號轉(zhuan)換成正比于(yu)液(ye)位變化的(de)(de)電(dian)(dian)(dian)(dian)(dian)阻信(xin)號，并將電(dian)(dian)(dian)(dian)(dian)子(zi)單元轉(zhuan)換成4～20mA或其(qi)它(ta)標準信(xin)號輸出。該變送器(qi)為(wei)模塊電(dian)(dian)(dian)(dian)(dian)路(lu)，具有(you)耐酸、防(fang)潮、防(fang)震(zhen)、防(fang)腐蝕等優點，電(dian)(dian)(dian)(dian)(dian)路(lu)內(nei)部含有(you)恒流反饋電(dian)(dian)(dian)(dian)(dian)路(lu)和內(nei)保(bao)護電(dian)(dian)(dian)(dian)(dian)路(lu)，可(ke)使(shi)(shi)輸出最大電(dian)(dian)(dian)(dian)(dian)流不超(chao)過(guo)28mA，因(yin)而能夠可(ke)靠地保(bao)護電(dian)(dian)(dian)(dian)(dian)源并使(shi)(shi)二(er)次儀表不被(bei)損壞。

熱電(dian)偶(ou)(ou)溫度變送器一(yi)般由(you)(you)基準(zhun)源、冷端補償、放(fang)大(da)單元、線性化(hua)處(chu)理(li)、V/I轉(zhuan)換、斷(duan)(duan)(duan)偶(ou)(ou)處(chu)理(li)、反接保(bao)護(hu)、限流保(bao)護(hu)等電(dian)路(lu)單元組成(cheng)。它是將(jiang)熱電(dian)偶(ou)(ou)產生的(de)熱電(dian)勢經冷端補償放(fang)大(da)后(hou)，再帽由(you)(you)線性電(dian)路(lu)消除(chu)熱電(dian)勢與溫度的(de)非(fei)線性誤差，最后(hou)放(fang)大(da)轉(zhuan)換為4～20mA電(dian)流輸出(chu)信號。為防(fang)止熱電(dian)偶(ou)(ou)測(ce)量中由(you)(you)于電(dian)偶(ou)(ou)斷(duan)(duan)(duan)絲(si)而使控溫失效造成(cheng)事故(gu)，變送器中還(huan)設有斷(duan)(duan)(duan)電(dian)保(bao)護(hu)電(dian)路(lu)。當熱電(dian)偶(ou)(ou)斷(duan)(duan)(duan)絲(si)或(huo)接解不良時，變送器會輸出(chu)最大(da)值(zhi)（28mA）以使儀表(biao)切斷(duan)(duan)(duan)電(dian)源。

E+H水分析變送器產品特性一覽