一、熱電偶介紹
熱電(dian)(dian)(dian)偶(ou)是利用熱電(dian)(dian)(dian)效應(ying)作為測量(liang)原(yuan)理的(de)一種無源傳(chuan)感器。所謂的(de)熱電(dian)(dian)(dian)效應(ying)即(ji)兩種不(bu)(bu)同(tong)(tong)成份的(de)導(dao)體(稱為熱電(dian)(dian)(dian)偶(ou)絲材(cai)(cai)或熱電(dian)(dian)(dian)極)兩端接合成回(hui)路(lu),當兩個接合點(dian)的(de)溫度(du)不(bu)(bu)同(tong)(tong)時,在回(hui)路(lu)中就會產生(sheng)電(dian)(dian)(dian)動勢的(de)現象。所以根據組成熱電(dian)(dian)(dian)偶(ou)兩種絲材(cai)(cai)的(de)材(cai)(cai)質不(bu)(bu)同(tong)(tong)可以得(de)到不(bu)(bu)同(tong)(tong)類型的(de)熱電(dian)(dian)(dian)偶(ou),不(bu)(bu)同(tong)(tong)型號(hao)之前也存(cun)在一定的(de)差(cha)異。
二、k型熱電偶與e型熱電偶區別
K型熱電偶與(yu)E型熱電偶的(de)區(qu)別在于熱電動(dong)勢、靈敏度、穩定性和均(jun)勻性、抗氧化性能(neng)和價格。
K型熱(re)(re)電偶適用(yong)于(yu)氧化(hua)性(xing)(xing)惰(duo)性(xing)(xing)氣(qi)(qi)氛(fen),而E型熱(re)(re)電偶適用(yong)于(yu)氧化(hua)性(xing)(xing)和(he)惰(duo)性(xing)(xing)氣(qi)(qi)氛(fen),但不能(neng)在高(gao)溫下(xia)使(shi)用(yong)硫(liu)、還原性(xing)(xing)或還原性(xing)(xing)氣(qi)(qi)氛(fen)中和(he)真空中。E型熱(re)(re)電偶具(ju)有穩定性(xing)(xing)好、抗氧化(hua)性(xing)(xing)能(neng)好、價格(ge)便宜等優點,但熱(re)(re)電動(dong)勢(shi)較大,靈敏度最高(gao),適用(yong)于(yu)高(gao)濕度氣(qi)(qi)氛(fen),但對于(yu)高(gao)濕度腐蝕不甚靈敏。
三、k型熱電偶和t型熱電偶的區別
k型熱(re)電偶和t型熱(re)電偶的區別主要在于測量(liang)范圍(wei):
k型,可以測量-200度(du)到1000多度(du)的范圍,缺點是超過居里點的時候(hou)會(hui)有(you)特征(zheng)曲(qu)線的跳變,大約150度(du)左右。t型是非磁(ci)性材料(liao),沒(mei)有(you)居里點,所以特征(zheng)曲(qu)線更連貫,效果好一些。溫度(du)范圍-200度(du)到350度(du)。