5D32022G01西屋

DCS系統(tǒng)的接地原則

    2.1 DCS系統(tǒng)設(shè)置的接地裝置

    (1) 操作臺、打印臺、服務(wù)器柜：設(shè)有保護(hù)地螺釘。
    (2) 繼電器柜、UPS柜、配電柜：設(shè)有保護(hù)地螺釘。
    (3) DCS的I/O機(jī)柜：設(shè)有屏蔽接地匯流排，保護(hù)地螺釘。系統(tǒng)地（+24V地）懸浮。
    (4) 儀表柜、手操盤臺：設(shè)有屏蔽地接地匯流排，保護(hù)地螺釘。
    (5) 安全柵柜：設(shè)有屏蔽地接地匯流排，本安地接地匯流排，保護(hù)地螺釘。

    2.2 信號屏蔽及其接地

    (1) 根據(jù)有關(guān)技術(shù)規(guī)定要求，計(jì)算機(jī)或 DCS系統(tǒng)信號電纜的屏蔽層不得浮空，必須接地，其接地方式應(yīng)符合下列規(guī)定：

    a. 當(dāng)信號源浮空時(shí)，屏蔽層應(yīng)在計(jì)算機(jī)側(cè)接地；
    b. 當(dāng)信號源接地時(shí)，屏蔽層應(yīng)在信號源側(cè)接地；
    c. 當(dāng)放大器浮空時(shí)，屏蔽層的一端與屏蔽罩相連，另一端宜接共模地（當(dāng)信號源接地時(shí)，接信號地。當(dāng)信號源浮空時(shí)接現(xiàn)場地）。

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