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
金jin屬shu氧yang化hua物wu半ban導dao體ti式shi傳chuan感gan器qi利li用yong被bei測ce氣qi體ti的de吸xi附fu作zuo用yong,改gai變bian半ban導dao體ti的de電dian導dao率lv,通tong過guo電dian流liu變bian化hua的de比bi較jiao,激ji發fa報bao警jing電dian路lu。由you於yu半ban導dao體ti式shi傳chuan感gan器qi測ce量liang時shi受shou環huan境jing影ying響xiang較jiao大da,輸shu出chu線xian形xing不bu穩wen定ding。金jin屬shu氧yang化hua物wu半ban導dao體ti式shi傳chuan感gan器qi,因yin其qi反fan應ying十shi分fen靈ling敏min,故gu目mu前qian廣guang泛fan使shi用yong的de領ling域yu為wei測ce量liang氣qi體ti的de微wei漏lou現xian象xiang。
催化燃燒式傳感器
催化燃燒式傳感器原理是目前最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、無wu與yu其qi他ta非fei可ke燃ran氣qi體ti的de交jiao叉cha幹gan擾rao等deng特te點dian。催cui化hua燃ran燒shao式shi傳chuan感gan器qi采cai用yong惠hui斯si通tong電dian橋qiao原yuan理li,感gan應ying電dian阻zu與yu環huan境jing中zhong的de可ke燃ran氣qi體ti發fa生sheng無wu焰yan燃ran燒shao,使shi溫wen度du使shi感gan應ying電dian阻zu的de阻zu值zhi發fa生sheng變bian化hua,打da破po電dian橋qiao平ping衡heng,使shi之zhi輸shu出chu穩wen定ding的de電dian流liu信xin號hao,再zai經jing過guo後hou期qi電dian路lu的de放fang大da、穩定和處理最終顯示可靠的數值。
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最zui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)。yongqingyanghuajia。yangqizaitongguodianjiezhishizaiyinyangjifashengyanghuahaiyuanfanying,shiyangjijinshulizihua,shifangchudianzi,dianliudedaxiaoyuyangqideduoshaochengzhengbi,youyuzhenggefanyingzhongyangjijinshuyouxiaohao,suoyichuanganqixuyaodingqigenghuan。muqianguoneijishuyiriquchengshu,wanquankeyiguochanhuacileichuanganqi。
紅外式傳感器
hongwaishichuanganqiliyonggezhongyuansuduimougetedingbochangdexishouyuanli,juyoukangzhongduxinghao,fanyinglingmin,duidaduoshutanqinghuahewudouyoufanying。danjiegoufuza,chengbengao。
PID光離子化氣體傳感器
PIDyouziwaidengguangyuanhelizishidengzhuyaobufengoucheng,zailizishiyouzhengfudianji,xingchengdianchang,daiceqitizaiziwaidengdezhaoshexia,lizihua,shengchengzhengfulizi,zaidianjijianxingchengdianliu,jingfangdashuchuxinhao。PID具有靈敏度高,無中毒問題,安全可靠等優點。
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