Motherboard digital input port: the instrument main board provides 3 programmable input port. receives the passive contact switch signal.

主板数字输入端口．仪表主板提供3个可编程输入端口，接收无源触点开关信号。

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There is a four-way signal input on the signal acquisition circuit board, which implements signal conditioning and analog-digital conversion.

信号采集板有四路信号输入，完成信号调理以及模数转换功能；

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