可燃(ran)性氣體檢測(ce)(ce)儀由檢測(ce)(ce)和探(tan)測(ce)(ce)兩部分組成，具有檢測(ce)(ce)及探(tan)測(ce)(ce)功能。

1、可燃性氣體檢(jian)測儀檢(jian)測部分(fen)的(de)原理

儀器的傳感器采用檢測元(yuan)件(jian)與固定電(dian)(dian)阻和調零電(dian)(dian)位器構成(cheng)檢測橋(qiao)路。橋(qiao)路以鉑絲(si)為載體(ti)(ti)催化(hua)元(yuan)件(jian)，通(tong)(tong)電(dian)(dian)后鉑絲(si)溫(wen)(wen)度上升至工作溫(wen)(wen)度，空氣(qi)(qi)(qi)以自然擴散方(fang)式或其(qi)它方(fang)式到達元(yuan)件(jian)表面。當空氣(qi)(qi)(qi)中無可燃(ran)(ran)性氣(qi)(qi)(qi)體(ti)(ti)時(shi)，橋(qiao)路輸(shu)(shu)出(chu)為零，當空氣(qi)(qi)(qi)中含有(you)可燃(ran)(ran)性氣(qi)(qi)(qi)體(ti)(ti)并擴散到檢測元(yuan)件(jian)上時(shi)，由(you)于催化(hua)作用產生(sheng)無焰燃(ran)(ran)燒，使檢測元(yuan)件(jian)溫(wen)(wen)度升高，鉑絲(si)電(dian)(dian)阻增大，使橋(qiao)路失去平(ping)衡，從而有(you)一電(dian)(dian)壓(ya)信號(hao)(hao)輸(shu)(shu)出(chu)，這個電(dian)(dian)壓(ya)的大小與可燃(ran)(ran)性氣(qi)(qi)(qi)體(ti)(ti)濃(nong)度成(cheng)正比(bi)，信號(hao)(hao)經(jing)放大，模數(shu)轉換，通(tong)(tong)過液體(ti)(ti)顯示器顯示出(chu)可燃(ran)(ran)性氣(qi)(qi)(qi)體(ti)(ti)的濃(nong)度。

2、可燃性(xing)氣體檢測(ce)儀探(tan)測(ce)部分的原理

當被測(ce)可(ke)燃性氣體濃(nong)度超過限定值(zhi)時，經過放大的橋路(lu)(lu)輸(shu)(shu)出電(dian)壓與電(dian)路(lu)(lu)探測(ce)設(she)定電(dian)壓，通過電(dian)壓比(bi)較(jiao)器，方波發生(sheng)器輸(shu)(shu)出一(yi)組方波信(xin)號，控制(zhi)聲、光探測(ce)電(dian)路(lu)(lu)，蜂(feng)鳴(ming)器發生(sheng)連續聲音，發光二極管閃(shan)亮，發出探測(ce)信(xin)號。