5A28137G04西屋

  DCS系統(tǒng)接地方式 DCS系統(tǒng)一般接地方式

    (1) 利用電氣接地網(wǎng)作為DCS接地網(wǎng)，即與電氣接地網(wǎng)共地； 
    (2) 設DCS系統(tǒng)專用獨立的接地網(wǎng)；
    (3) 設DCS專用接地網(wǎng)，經接地線、再接至電氣接地網(wǎng)；

    由于第三種接地方式與第二種接地方式有較多相同處，過去，計算機或DCS系統(tǒng)曾經較多的采用過專用的接地網(wǎng)。但這種接地方式存在的缺點是：占地面積太大，投資高，電纜及接地網(wǎng)鋼材耗量大，距廠房有相當?shù)木嚯x（因不易在廠房內找到合適的位置），管理、維護、測量及查找接地極和接地線不方便，且效果不甚良好。根據(jù)實際運行表明，設置專用的DCS接地網(wǎng)是既困難又不安全的。如某電廠曾因接地問題，造成機組跳閘數(shù)十次。根據(jù)調查，不少電廠DCS后來改用電氣接地網(wǎng)接地，取得了良好的效果。

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