選擇一個(gè)熱敏電阻或RTD

　　選擇一個(gè)熱敏電阻或RTD

　　傳感器用于測量溫度可以包括熱電偶，電阻溫度裝置（RTDs和熱敏電阻），紅外輻射器，金屬設(shè)備，液體膨脹設(shè)備，及其他。在過去的幾年里，在精確度、互換性和穩(wěn)定性方面，令人印象深刻和廣泛的改進(jìn)促使許多應(yīng)用程序增加熱敏電阻的使用，這將是本文的重點(diǎn)。

　　這些熱敏電阻（因此，它們的名稱，“熱”和“電阻”的收縮）在溫度變化時(shí)具有電阻大且可預(yù)測的變化。熱敏電阻越大，電阻值越高，其耗散功率越大。熱敏電阻是高度敏感的，重復(fù)性很好的電阻-溫度特性。

　　而這些設(shè)備都是廉價(jià)收購，真正的儲(chǔ)蓄是因?yàn)樗鼈儾恍枰惭b傳感器的壽命期間校準(zhǔn)或校準(zhǔn)。相反，他們是年齡離開制造商使漂移最小化之前，而這些傳感器一般輕微的溫度變化反應(yīng)迅速，探頭類型的熱敏電阻的反應(yīng)時(shí)間是物質(zhì)依賴。

　　Types of resistive temperature sensors

　　Two types of resistive temperature sensing devices are based on changes in the electrical resistance of material relative to temperature changes： negative temperature coefficient （NTC） thermistors and resistive temperature detectors （RTDs）。 We will look at both， starting with NTCs.

　　While the NTC variety is manufactured from the oxide of manganese， cobalt， copper， and nickel， it operates over a range of –200°C to 1，000°C. Thermistors can be bought in glass bead， disc， chips， and probe options. Used extensively in such applications as temperature measurement and control， temperature compensation， surge suppression， and fluid flow measurement， they should be selected when a continuous change of resistance is necessary spanning a wide temperature range. They offer high stability and a high degree of sensitivity.