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          1771-DRS1

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          產(chǎn)品價格: /人民幣 
          最后更新: 2019-08-12 17:27:55
          產(chǎn)品產(chǎn)地: 美國
          發(fā)貨地: 福州 (發(fā)貨期:當天內(nèi)發(fā)貨)
          供應(yīng)數(shù)量: 不限
          有效期: 長期有效
          最少起訂: 1
          瀏覽次數(shù): 293
          詢價  家家通會員產(chǎn)品
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          產(chǎn)品詳細說明

          1771-DRS1現(xiàn)貨 in stock! 歡迎來電咨詢~!!

          1771-DRS1


          DCS系統(tǒng)在工業(yè)生產(chǎn)過程的廣泛應(yīng)用,使可靠性、穩(wěn)定性問題更加突出,也使人們對整個系統(tǒng)要求越來越高。人們希望DCS系統(tǒng)盡量少出故障,又希望DCS系統(tǒng)一旦出現(xiàn)故障,能盡快診斷出故障部位,并盡快修復(fù),使系統(tǒng)重新工作。下面簡單介紹故障大體分類及故障診斷的一般方法。
            一、DCS系統(tǒng)故障的分類
            為了便于分析、診斷DCS系統(tǒng)故障發(fā)生的部位和產(chǎn)生原因,可以把故障大致分為如下幾類。
            1、現(xiàn)場儀表設(shè)備故障
            現(xiàn)場儀表設(shè)備包括與生產(chǎn)過程直接聯(lián)系的各種變送器、各種開關(guān)、執(zhí)行機構(gòu)、負載等。現(xiàn)場儀表設(shè)備發(fā)生故障,直接影響DCS系統(tǒng)的控制功能。在目前的DCS控制系統(tǒng)中,這類故障占絕大部分。這類故障一般是由于儀表設(shè)備本身的質(zhì)量和壽命所致。
            2、系統(tǒng)故障
            這是影響系統(tǒng)運行的全局性故障。系統(tǒng)故障可分為固定性故障和偶然性故障。這類故障一般比較明顯且影響也是局部的,它們主要是由使用不當或使用時間較長,模板內(nèi)元件老化所致。
            3、硬件故障
            這類故障主要指DCS系統(tǒng)中的模板(特別是I/O模板)損壞造成的故障。這類故障一般比較明顯且影響也是局部的,它們主要是由使用不當或使用時間較長,模板內(nèi)元件老化所致。
            4、軟件故障
            這類故障是軟件本身所包含的錯誤所引起的,軟件故障又可分為系統(tǒng)軟件故障和應(yīng)用軟件故障。系統(tǒng)軟件是DCS系統(tǒng)帶來的,若設(shè)計考慮不周,在執(zhí)行中一旦條件滿足就會引發(fā)故障,造成停機或死機等現(xiàn)象。此類故障并不常見。應(yīng)用軟件是用戶自己編定的。在實際工程應(yīng)用中,由于應(yīng)用軟件工作復(fù)雜,工作量大,因此軟件錯誤幾乎難以避免,這就要求在DCS系統(tǒng)調(diào)試及試運行中十分認真,及時發(fā)現(xiàn)并解決。
            5、操作、使用不當造成故障
            在實際運行操作中,有時會出現(xiàn)DCS系統(tǒng)某功能不能使用或某控制不封不能正常工作,但實際上DCS系統(tǒng)并沒有毛病,而是操作人員操作不熟練或操作錯誤所引起的。這對于初次使用DCS系統(tǒng)的操作工較為常見。

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