7．输入继电器是PLC接受外部输入的开关信号的窗口，下面对其描述正确的是（）。输入继电器有线圈和触点输入继电器触点可以无限制使用输入继电器的状态仅取决于用户程序的控制输入继电器只有常开触点 - 查题网

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7．输入继电器是PLC接受外部输入的开关信号的窗口，下面对其描述正确的是（）。
输入继电器有线圈和触点
输入继电器触点可以无限制使用
输入继电器的状态仅取决于用户程序的控制
输入继电器只有常开触点

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可编程控制器应用

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