在做高低溫環境試驗時，首先在計算機上位機界面設定測試的溫度范圍，然后根據測試產品的需求使高低溫試驗箱開始工作。如先做低溫試驗，其具體工作流程為：制冷降溫→制冷指示燈點亮→制冷保溫直到溫度降至設定的溫→加熱升溫→加熱指示燈點亮→加熱保溫直到溫度升高至設定高溫值，結束次高低溫試驗。

    本系統設計的高低溫試驗箱是由箱蓋、箱體外殼、制(zhi)冷(leng)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)、加(jia)熱(re)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)和保溫隔熱(re)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)等組成(cheng)。其中，制(zhi)冷(leng)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)由3部(bu)分組成(cheng)，分別為半導體制(zhi)冷(leng)片(pian)、風扇和散熱(re)片(pian)，其安(an)裝(zhuang)(zhuang)(zhuang)于箱體的左右兩(liang)邊。加(jia)熱(re)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)主要由硅膠發熱(re)片(pian)和加(jia)熱(re)裝(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)支架板(ban)構(gou)成(cheng)，固定安(an)裝(zhuang)(zhuang)(zhuang)在箱體前后壁上。高低溫試驗箱機(ji)械結構(gou)示意如圖1所示。

    本系(xi)統(tong)主(zhu)(zhu)要(yao)由傳感(gan)器(qi)、計算機、加熱裝(zhuang)(zhuang)置、制(zhi)(zhi)冷裝(zhuang)(zhuang)置，及(ji)相關(guan)電路(lu)組成。通過計算機上(shang)位(wei)機來設置試(shi)驗(yan)需(xu)要(yao)測試(shi)的(de)溫(wen)(wen)(wen)度(du)范圍(wei)，利用控(kong)(kong)制(zhi)(zhi)器(qi)對箱內的(de)溫(wen)(wen)(wen)度(du)進行(xing)多點(dian)采集，主(zhu)(zhu)控(kong)(kong)芯(xin)片將(jiang)多點(dian)采集的(de)溫(wen)(wen)(wen)度(du)信(xin)(xin)息進行(xing)處(chu)理，同(tong)時(shi)(shi)通過RS485的(de)通信(xin)(xin)方式將(jiang)主(zhu)(zhu)控(kong)(kong)制(zhi)(zhi)器(qi)得(de)到的(de)溫(wen)(wen)(wen)度(du)信(xin)(xin)息發送至計算機上(shang)位(wei)機，由上(shang)位(wei)機顯(xian)示當(dang)前工作狀態及(ji)溫(wen)(wen)(wen)度(du)值(zhi)。由主(zhu)(zhu)控(kong)(kong)制(zhi)(zhi)器(qi)發出信(xin)(xin)號，使驅動電路(lu)導通，驅動制(zhi)(zhi)冷裝(zhuang)(zhuang)置或(huo)(huo)加熱裝(zhuang)(zhuang)置進行(xing)降溫(wen)(wen)(wen)或(huo)(huo)升溫(wen)(wen)(wen)，當(dang)采集得(de)到的(de)溫(wen)(wen)(wen)度(du)達到設置溫(wen)(wen)(wen)度(du)的(de)值(zhi)時(shi)(shi)，試(shi)驗(yan)箱的(de)溫(wen)(wen)(wen)度(du)控(kong)(kong)制(zhi)(zhi)系(xi)統(tong)將(jiang)會自動斷開。溫(wen)(wen)(wen)度(du)控(kong)(kong)制(zhi)(zhi)系(xi)統(tong)的(de)硬件構成如圖2所(suo)示。