天康超聲波液位計

可(ke)(ke)采用(yong)二(er)線(xian)制(zhi)(zhi)(zhi)、三線(xian)制(zhi)(zhi)(zhi)或(huo)四線(xian)制(zhi)(zhi)(zhi)技術，二(er)線(xian)制(zhi)(zhi)(zhi)為(wei)：供(gong)(gong)電(dian)(dian)(dian)與信(xin)號(hao)輸出(chu)共(gong)用(yong)；三線(xian)制(zhi)(zhi)(zhi)為(wei)：供(gong)(gong)電(dian)(dian)(dian)回(hui)路(lu)和(he)信(xin)號(hao)輸出(chu)回(hui)路(lu)獨立，當(dang)采用(yong)直流(liu)(liu)24v供(gong)(gong)電(dian)(dian)(dian)時，可(ke)(ke)使用(yong)一(yi)(yi)根3芯(xin)電(dian)(dian)(dian)纜線(xian)，供(gong)(gong)電(dian)(dian)(dian)負端和(he)信(xin)號(hao)輸出(chu)負端共(gong)用(yong)一(yi)(yi)根芯(xin)線(xian)；四線(xian)制(zhi)(zhi)(zhi)為(wei)：當(dang)采用(yong)交(jiao)流(liu)(liu)220v供(gong)(gong)電(dian)(dian)(dian)時，或(huo)者(zhe)當(dang)采用(yong)直流(liu)(liu)24v供(gong)(gong)電(dian)(dian)(dian)，要求供(gong)(gong)電(dian)(dian)(dian)回(hui)路(lu)與信(xin)號(hao)輸出(chu)回(hui)路(lu)*隔(ge)離(li)時，應使用(yong)一(yi)(yi)根4芯(xin)電(dian)(dian)(dian)纜線(xian)。直流(liu)(liu)或(huo)交(jiao)流(liu)(liu)供(gong)(gong)電(dian)(dian)(dian)，具(ju)有4~20mADC，高(gao)低位開關量輸出(chu)。

天康超聲波液位計

超(chao)聲(sheng)波液位計一般采(cai)用(yong)收(shou)發合一的(de)(de)陶瓷超(chao)聲(sheng)波換能器(qi),聲(sheng)波的(de)(de)發射(she)和(he)接(jie)收(shou)都由同一個探(tan)(tan)頭(tou)完成(cheng)。探(tan)(tan)頭(tou)向被(bei)測液面發射(she)超(chao)聲(sheng)波信號(hao),超(chao)聲(sheng)波由探(tan)(tan)頭(tou)經傳(chuan)播介(jie)質傳(chuan)播至被(bei)測液面,在液面上形(xing)成(cheng)反射(she),反射(she)波沿原(yuan)路徑傳(chuan)播至探(tan)(tan)頭(tou),被(bei)探(tan)(tan)頭(tou)接(jie)收(shou)

原理要求
超聲波液位計工作時，高頻脈沖聲波由換能器（探頭）發出，遇被測物體（水面）表面被反射，折回的反射回波被同一換能器（探頭）接收，轉換成電信號。脈沖發送和接收之間的時間（聲波的運動時間）與換能器到物體表面的距離成正比，聲波傳輸的距離S與聲速C和傳輸時間T之間的關系可以用公式表示：S= CⅩT/2

安裝超(chao)聲(sheng)波(bo)液位(wei)(wei)計(ji)時必須(xu)考慮超(chao)聲(sheng)波(bo)液位(wei)(wei)計(ji)的盲(mang)區(qu)問題。當液位(wei)(wei)進入盲(mang)區(qu)后(hou)，超(chao)聲(sheng)波(bo)變送器(qi)就無法測量液位(wei)(wei)了，所以在確定超(chao)聲(sheng)波(bo)液位(wei)(wei)計(ji)的量程時，必須(xu)留出(chu)50公分的余量，安裝時，變送器(qi)探頭必須(xu)高出(chu)液位(wei)(wei)50公分左右。這(zhe)樣才能(neng)保證(zheng)對液位(wei)(wei)的準確監(jian)測及保證(zheng)超(chao)聲(sheng)波(bo)液位(wei)(wei)計(ji)的安全。

在(zai)實際使(shi)用(yong)中，因為(wei)安裝時考慮(lv)不(bu)周，液位(wei)計(ji)(ji)被水淹沒，致使(shi)液位(wei)計(ji)(ji)損(sun)壞。