壓力變(bian)送器（pressure transmitter）是(shi)指(zhi)(zhi)以輸(shu)出(chu)為標準信號(hao)的壓力傳(chuan)感器，是(shi)一種接受(shou)壓力變(bian)量按比例轉(zhuan)(zhuan)換為標準輸(shu)出(chu)信號(hao)的儀表(biao)。它(ta)能將測壓元件傳(chuan)感器感受(shou)到的氣(qi)體、液體等(deng)(deng)物(wu)理壓力參(can)數轉(zhuan)(zhuan)變(bian)成(cheng)標準的電信號(hao)（如4~20mADC等(deng)(deng)），以供給(gei)指(zhi)(zhi)示(shi)報警儀、記錄儀、調節(jie)器等(deng)(deng)二(er)次(ci)儀表(biao)進(jin)行測量、指(zhi)(zhi)示(shi)和(he)過程調節(jie)；

壓(ya)(ya)力變(bian)送器是工業(ye)實踐中為常用(yong)(yong)的(de)(de)一種(zhong)(zhong)傳感器，其(qi)廣泛應用(yong)(yong)于(yu)各種(zhong)(zhong)工業(ye)自(zi)控(kong)環境(jing)，涉及水利水電、鐵路交(jiao)通(tong)、智能建筑、生(sheng)產自(zi)控(kong)、航空航天(tian)、、石(shi)化、油井、電力、船(chuan)舶(bo)、機床、管(guan)道等眾多行(xing)業(ye)。下面(mian)就簡單(dan)介紹一些常用(yong)(yong)壓(ya)(ya)力變(bian)送器的(de)(de)原理及其(qi)應用(yong)(yong)、壓(ya)(ya)力變(bian)送器是用(yong)(yong)于(yu)測(ce)量(liang)液(ye)體(ti)(ti)、氣體(ti)(ti)或蒸汽的(de)(de)液(ye)位(wei)、密(mi)度和壓(ya)(ya)力，然后將壓(ya)(ya)力信號轉變(bian)成4～20mA DC信號輸出(chu)。

      壓(ya)(ya)力(li)變(bian)(bian)(bian)送器(qi)主要(yao)有電(dian)容式(shi)壓(ya)(ya)力(li)變(bian)(bian)(bian)送器(qi)和(he)擴散硅(gui)壓(ya)(ya)力(li)變(bian)(bian)(bian)送器(qi)，陶瓷壓(ya)(ya)力(li)變(bian)(bian)(bian)送器(qi)，應變(bian)(bian)(bian)式(shi)壓(ya)(ya)力(li)變(bian)(bian)(bian)送器(qi)等(deng)。壓(ya)(ya)力(li)變(bian)(bian)(bian)送器(qi)根據測壓(ya)(ya)范(fan)圍(wei)可分成一(yi)般(ban)壓(ya)(ya)力(li)變(bian)(bian)(bian)送器(qi)（0.001MPa～35MPa）和(he)微差壓(ya)(ya)變(bian)(bian)(bian)送器(qi)（0～1.5kPa），負壓(ya)(ya)變(bian)(bian)(bian)送器(qi)三種。

      壓(ya)(ya)(ya)(ya)(ya)力(li)(li)(li)(li)變送器(qi)(qi)的主(zhu)要(yao)作(zuo)用把(ba)壓(ya)(ya)(ya)(ya)(ya)力(li)(li)(li)(li)信(xin)號傳(chuan)到(dao)電子設備(bei)，進而在(zai)計(ji)算機顯(xian)示壓(ya)(ya)(ya)(ya)(ya)力(li)(li)(li)(li)其原理大致是：將水壓(ya)(ya)(ya)(ya)(ya)這種壓(ya)(ya)(ya)(ya)(ya)力(li)(li)(li)(li)的力(li)(li)(li)(li)學(xue)信(xin)號轉變成(cheng)電流(liu)(liu)(liu)（4-20mA）這樣的電子信(xin)號壓(ya)(ya)(ya)(ya)(ya)力(li)(li)(li)(li)和電壓(ya)(ya)(ya)(ya)(ya)或(huo)電流(liu)(liu)(liu)大小成(cheng)線性(xing)關系(xi)，一般(ban)是正比(bi)關系(xi)。所以，變送器(qi)(qi)輸出的電壓(ya)(ya)(ya)(ya)(ya)或(huo)電流(liu)(liu)(liu)隨(sui)壓(ya)(ya)(ya)(ya)(ya)力(li)(li)(li)(li)增大而增大由此(ci)得出一個壓(ya)(ya)(ya)(ya)(ya)力(li)(li)(li)(li)和電壓(ya)(ya)(ya)(ya)(ya)或(huo)電流(liu)(liu)(liu)的關系(xi)式壓(ya)(ya)(ya)(ya)(ya)力(li)(li)(li)(li)變送器(qi)(qi)的被測介(jie)質的兩種壓(ya)(ya)(ya)(ya)(ya)力(li)(li)(li)(li)通入高、低兩壓(ya)(ya)(ya)(ya)(ya)力(li)(li)(li)(li)室，低壓(ya)(ya)(ya)(ya)(ya)室壓(ya)(ya)(ya)(ya)(ya)力(li)(li)(li)(li)采用大氣壓(ya)(ya)(ya)(ya)(ya)或(huo)真空，作(zuo)用在(zai)δ元（即敏感元件）的兩側隔(ge)(ge)離膜片上，通過隔(ge)(ge)離片和元件內的填充液傳(chuan)送到(dao)測量膜片兩側。

       壓(ya)力變送器是由測量膜片(pian)與兩(liang)側絕緣片(pian)上(shang)的電(dian)(dian)極各(ge)組成(cheng)一個電(dian)(dian)容器。當兩(liang)側壓(ya)力不一致時，致使測量膜片(pian)產生位(wei)移，其位(wei)移量和壓(ya)力差成(cheng)正比，故兩(liang)側電(dian)(dian)容量就不等(deng)，通過振蕩和解調(diao)環(huan)節。

水壓油壓氣壓變送器4-20mA輸出0-10v

設備型壓(ya)力變送器小體積 輸出4-20mA兩線制(zhi)(zhi)，0-10mA，0-20mA，4-20mA三線制(zhi)(zhi)輸出，0-5V，0-10V三線制(zhi)(zhi)，RS485四線制(zhi)(zhi)數字(zi)通(tong)訊(xun)輸出

水壓油壓氣壓變送器4-20mA輸出0-10v

設備型壓(ya)力變送器小體積 輸(shu)出4-20mA兩線制，0-10mA，0-20mA，4-20mA三線制輸(shu)出，0-5V，0-10V三線制，RS485四線制數(shu)字(zi)通訊輸(shu)出