檢測氣體的濃度依賴於氣體檢測變送器,傳感器是其核心部分,按照檢測原理的不同,主要分為金屬氧化物半導體式傳感器、催化燃燒式傳感器、定電位電解式氣體傳感器、迦伐尼電池式氧氣傳感器、紅外式傳感器、PID光離子化傳感器等,以下簡單闡述各種傳感器的原理及特點。
金屬氧化物半導體式傳感器
jinshuyanghuawubandaotishichuanganqiliyongbeiceqitidexifuzuoyong,gaibianbandaotidediandaolv,tongguodianliubianhuadebijiao,jifabaojingdianlu。youyubandaotishichuanganqiceliangshishouhuanjingyingxiangjiaoda,shuchuxianxingbuwending。jinshuyanghuawubandaotishichuanganqi,yinqifanyingshifenlingmin,gumuqianguangfanshiyongdelingyuweiceliangqitideweilouxianxiang。
催化燃燒式傳感器
催化燃燒式傳感器原理是目前廣泛使用的檢測可燃氣體的原理之一,具有輸出信號線形好、指數可靠、價格便宜、wuyuqitafeikeranqitidejiaochaganraodengtedian。cuihuaranshaoshichuanganqicaiyonghuisitongdianqiaoyuanli,ganyingdianzuyuhuanjingzhongdekeranqitifashengwuyanranshao,shiwendushiganyingdianzudezuzhifashengbianhua,dapodianqiaopingheng,shizhishuchuwendingdedianliuxinhao,zaijingguohouqidianludefangda、穩定和處理終顯示可靠的數值。
定電位電解式氣體傳感器
定(ding)電(dian)位(wei)電(dian)解(jie)式(shi)傳(chuan)感(gan)器(qi)是(shi)目(mu)前(qian)測(ce)毒(du)類(lei)現(xian)場(chang)廣(guang)泛(fan)使(shi)用(yong)的(de)一(yi)種(zhong)技(ji)術(shu),在(zai)此(ci)方(fang)麵(mian)國(guo)外(wai)技(ji)術(shu)領(ling)先(xian),因(yin)此(ci)此(ci)類(lei)傳(chuan)感(gan)器(qi)大(da)都(dou)依(yi)賴(lai)進(jin)口(kou)。定(ding)電(dian)位(wei)電(dian)解(jie)式(shi)氣(qi)體(ti)傳(chuan)感(gan)器(qi)的(de)結(jie)構(gou):在一個塑料製成的筒狀池體內,安裝工作電極、對dui電dian極ji和he參can比bi電dian極ji,在zai電dian極ji之zhi間jian充chong滿man電dian解jie液ye,由you多duo孔kong四si氟fu乙yi烯xi做zuo成cheng的de隔ge膜mo,在zai頂ding部bu封feng裝zhuang。前qian置zhi放fang大da器qi與yu傳chuan感gan器qi電dian極ji的de連lian接jie,在zai電dian極ji之zhi間jian施shi加jia了le一yi定ding的de電dian位wei,使shi傳chuan感gan器qi處chu於yu工gong作zuo狀zhuang態tai。氣qi體ti與yu的de電dian解jie質zhi內nei的de工gong作zuo電dian極ji發fa生sheng氧yang化hua或huo還hai原yuan反fan應ying,在zai對dui電dian極ji發fa生sheng還hai原yuan或huo氧yang化hua反fan應ying,電dian極ji的de平ping衡heng電dian位wei發fa生sheng變bian化hua,變bian化hua值zhi與yu氣qi體ti濃nong度du成cheng正zheng比bi。
迦伐尼電池式氧氣傳感器
隔膜迦伐尼電池式氧氣傳感器的結構:在塑料容器的一麵裝有對氧氣透過性良好的、厚10~30μm的聚四氟乙烯透氣膜,在其容器內側緊粘著貴金屬(鉑、黃金、銀等)陰電極,在容器的另一麵內側或容器的空餘部分形成陽極(用鉛、鎘等離子化傾向大的金屬)。用yong氫qing氧yang化hua鉀jia。氧yang氣qi在zai通tong過guo電dian解jie質zhi時shi在zai陰yin陽yang極ji發fa生sheng氧yang化hua還hai原yuan反fan應ying,使shi陽yang極ji金jin屬shu離li子zi化hua,釋shi放fang出chu電dian子zi,電dian流liu的de大da小xiao與yu氧yang氣qi的de多duo少shao成cheng正zheng比bi,由you於yu整zheng個ge反fan應ying中zhong陽yang極ji金jin屬shu有you消xiao耗hao,所suo以yi傳chuan感gan器qi需xu要yao定ding期qi更geng換huan。目mu前qian國guo內nei技ji術shu已yi日ri趨qu成cheng熟shu,完wan全quan可ke以yi國guo產chan化hua此ci類lei傳chuan感gan器qi。
紅外式傳感器
紅(hong)外(wai)式(shi)傳(chuan)感(gan)器(qi)利(li)用(yong)各(ge)種(zhong)元(yuan)素(su)對(dui)某(mou)個(ge)特(te)定(ding)波(bo)長(chang)的(de)吸(xi)收(shou)原(yuan)理(li),具(ju)有(you)抗(kang)中(zhong)毒(du)性(xing)好(hao),反(fan)應(ying)靈(ling)敏(min),對(dui)大(da)多(duo)數(shu)碳(tan)氫(qing)化(hua)合(he)物(wu)都(dou)有(you)反(fan)應(ying)。但(dan)結(jie)構(gou)複(fu)雜(za),成(cheng)本(ben)高(gao)。
PID光離子化氣體傳感器
PID由you紫zi外wai燈deng光guang源yuan和he離li子zi室shi等deng主zhu要yao部bu分fen構gou成cheng,在zai離li子zi室shi有you正zheng負fu電dian極ji,形xing成cheng電dian場chang,待dai測ce氣qi體ti在zai紫zi外wai燈deng的de照zhao射she下xia,離li子zi化hua,生sheng成cheng正zheng負fu離li子zi,在zai電dian極ji間jian形xing成cheng電dian流liu,經jing放fang大da輸shu出chu信xin號hao。PID具有靈敏度高,無中毒問題,安全可靠等優點。
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