E+H水分析變送器產品特性一覽

壓(ya)力變送(song)器(qi)也稱差變送(song)器(qi)，由測壓(ya)元件傳感器(qi)、模塊電路、顯(xian)示表頭、表殼(ke)和過程連接(jie)件等組成。它(ta)能(neng)將接(jie)收的氣體、液(ye)體等壓(ya)力信(xin)號轉變成標準的電流電壓(ya)信(xin)號，以供給指(zhi)示報警儀、記錄儀、調節器(qi)等二次儀表進行(xing)測量、指(zhi)示和過程調節。

壓力(li)變(bian)(bian)送器(qi)測量(liang)原(yuan)理(li)是(shi)：流(liu)(liu)程(cheng)壓力(li)和(he)參考壓力(li)分別作(zuo) 變(bian)(bian)送器(qi)（圖(tu)10）用于集成(cheng)(cheng)硅壓力(li)敏感元件的兩端，其差壓使(shi)硅片(pian)變(bian)(bian)形（位移很小，僅μm級），以使(shi)硅片(pian)上(shang)用半導體技術制成(cheng)(cheng)的全動(dong)態惠(hui)斯(si)登電(dian)(dian)(dian)橋在外部電(dian)(dian)(dian)流(liu)(liu)源(yuan)驅動(dong)下輸(shu)出正比于壓力(li)的mV級電(dian)(dian)(dian)壓信號。由于硅材料(liao)的強性(xing)，所(suo)以輸(shu)出信號的線(xian)性(xing)度及變(bian)(bian)差指標(biao)均很高(gao)。工作(zuo)時，壓力(li)變(bian)(bian)送器(qi)將被測物理(li)量(liang)轉換成(cheng)(cheng)mV級的電(dian)(dian)(dian)壓信號，并送往放(fang)大倍數很高(gao)而又可以互相(xiang)抵消溫度漂(piao)移的差動(dong)式放(fang)大器(qi)。放(fang)大后的信號經電(dian)(dian)(dian)壓電(dian)(dian)(dian)流(liu)(liu)轉換變(bian)(bian)換成(cheng)(cheng)相(xiang)應的電(dian)(dian)(dian)流(liu)(liu)信號，再經過非線(xian)性(xing)校正，最后產(chan)生與輸(shu)入壓力(li)成(cheng)(cheng)線(xian)性(xing)對應關系的標(biao)準電(dian)(dian)(dian)流(liu)(liu)電(dian)(dian)(dian)壓信號。

軟件的使用(yong)同(tong)樣十分(fen)簡單。操(cao)作(zuo)向(xiang)導(dao)直觀明了(le)，引(yin)導(dao)用(yong)戶逐(zhu)步完成儀表設(she)(she)置、功能安全測(ce)試和驗證測(ce)試，降低(di)操(cao)作(zuo)錯誤(wu)的發生幾率(lv)。使用(yong)移(yi)動設(she)(she)備(bei)和安全Bluetooth藍牙(ya)連接(jie)，通(tong)過app可以遠程控制變(bian)送器(qi)。

熱(re)電(dian)阻(zu)溫度變(bian)送器(qi)是由基準單(dan)元(yuan)、R/V轉(zhuan)(zhuan)換(huan)(huan)單(dan)元(yuan)、線(xian)(xian)性電(dian)路、 變(bian)送器(qi)（圖11）反接保護、限流保護、V/I轉(zhuan)(zhuan)換(huan)(huan)單(dan)元(yuan)等組成。測溫熱(re)電(dian)阻(zu)信號轉(zhuan)(zhuan)換(huan)(huan)放(fang)大(da)后，再由線(xian)(xian)性電(dian)路對溫度與(yu)電(dian)阻(zu)的非線(xian)(xian)性關系進行補償，經V/I轉(zhuan)(zhuan)換(huan)(huan)電(dian)路后輸出一個(ge)與(yu)被測溫度成線(xian)(xian)性關系的4～20mA的恒流信號。

一般磁性浮球的(de)比(bi)重小(xiao)于(yu)0.5，可漂于(yu)液面之上(shang)并沿測量(liang)導(dao)管(guan)上(shang)下移(yi)動(dong)。導(dao)管(guan)內裝有(you)測量(liang)元件，它可以在外磁作(zuo)用下將(jiang)被(bei)測液位(wei)信號(hao)轉(zhuan)換成(cheng)正比(bi)于(yu)液位(wei)變(bian)化的(de)電(dian)(dian)阻信號(hao)，并將(jiang)電(dian)(dian)子單元轉(zhuan)換成(cheng)4～20mA或其它標準信號(hao)輸(shu)出。該變(bian)送器為模塊電(dian)(dian)路(lu)(lu)(lu)，具有(you)耐(nai)酸(suan)、防(fang)潮、防(fang)震、防(fang)腐(fu)蝕等優點(dian)，電(dian)(dian)路(lu)(lu)(lu)內部含有(you)恒流反饋電(dian)(dian)路(lu)(lu)(lu)和內保(bao)護(hu)電(dian)(dian)路(lu)(lu)(lu)，可使(shi)輸(shu)出最大電(dian)(dian)流不超(chao)過28mA，因而能夠可靠(kao)地保(bao)護(hu)電(dian)(dian)源(yuan)并使(shi)二次儀表不被(bei)損壞。

熱(re)電(dian)偶(ou)溫度變送(song)器一般由(you)基準源(yuan)、冷端補(bu)償、放大(da)(da)單(dan)元(yuan)、線性化(hua)處理(li)、V/I轉換、斷(duan)(duan)(duan)偶(ou)處理(li)、反接(jie)保護(hu)、限(xian)流保護(hu)等(deng)電(dian)路單(dan)元(yuan)組成(cheng)。它(ta)是將熱(re)電(dian)偶(ou)產生的熱(re)電(dian)勢經冷端補(bu)償放大(da)(da)后，再(zai)帽由(you)線性電(dian)路消除熱(re)電(dian)勢與溫度的非線性誤差，最后放大(da)(da)轉換為4～20mA電(dian)流輸出信號(hao)。為防止熱(re)電(dian)偶(ou)測量中(zhong)由(you)于電(dian)偶(ou)斷(duan)(duan)(duan)絲(si)而使(shi)控(kong)溫失效(xiao)造成(cheng)事(shi)故(gu)，變送(song)器中(zhong)還設有斷(duan)(duan)(duan)電(dian)保護(hu)電(dian)路。當熱(re)電(dian)偶(ou)斷(duan)(duan)(duan)絲(si)或(huo)接(jie)解不良時(shi)，變送(song)器會(hui)輸出最大(da)(da)值（28mA）以使(shi)儀表切斷(duan)(duan)(duan)電(dian)源(yuan)。

E+H水分析變送器產品特性一覽