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一、概述微型计算机用于数据采集及过程控制必须要处理过程输入若干类型的信号,处理这些过程输入的硬件部分称为过程输入通道。它将各种类型输入信号变换成计算机能够接收的数字信息。过程输入通道的种类主要包括: 1.模拟量输入通道(AI):它主要用于将模拟量输入信号,经过采样、放大、模拟数字转换后送入计算机中。一般分非隔离型、半隔离型和全隔离型。非隔离型是指模拟量信号的“地”与计算机之间不隔离,抗共模干扰主要依靠差分输入;半隔离型是指模拟信号的“地”与计算机之间隔离,但各个输入通道之间不隔离;全隔离型是指模拟量信号的“地”与计算机“地”隔离,各被测信号的“地”之间也隔离,称Fully-Floting(全浮空)。
First, an overview Microcomputer for data acquisition and process control process must be entered several types of signals, the hardware part of the input process of these processes is called the process input channel. It transforms various types of input signals into digital information that the computer can receive. Process input channel types include: 1. Analog input channel (AI): It is mainly used for analog input signal, after sampling, amplification, analog-digital conversion into the computer. General sub-non-isolated, semi-isolated and fully isolated. Non-isolated means that the “ground” of the analog signal is not isolated from the computer, the anti-common-mode interference mainly depends on the differential input; the semi-isolated means that the “ground” of the analog signal is isolated from the computer, Isolation between the various input channels; full isolation refers to the analog signal “ground ” and the computer “ground ” isolation, the measured signal “ground ” is also isolated, called Fully-Floting (Full floating).