智能化工业仪表的抗干扰和人机界面的完善方法

在智能化工业仪表的设计中，为提高其抗干扰性能，完善人机界面，可采用差分输入抑制共态噪声，提高复位的可靠性抑制干扰，同时本文又提出了通过抑制共态噪声，提高复位的可靠性抑制干扰，同时本文又提出了通过提高采样频率来抑制常态噪声的方法；工业控制中，所处理的可能是温度、压力或流量，液位等各种信号，滤波时间常数应设计为可变参数，针对国产仪表仅给定了滤波参数，且未给出滤波系数与时间常数的函数关系，只能凭摸索设定

A METHOD TO IMPROVE THE ANTI INTERFERENCE PERFORMANCE AND PERFECT THE MMI OF THE INTELLIGENT INDUSTRIAL INSTRUMENTS

In the process of the design of intelligent industrial instruments,in order to improve its performance of anti interference and perfect the MMI,it is possible to introduce the differential inputs to suppress common mode noise and improve the reliability of reset to reduce power disturbance.This paper suggests a method in suppressing normal noise by improving sample frequency.In the industrial control,all kinds of signals are processed such as temperature,pressure, flow or level etc.and the time constant of wave filter should be designed as variable parameter.In view of the situation for the domestic instruments only the filter coefficient is given and the functional relationship between the filter coefficient and the time constant has to be tried to find out by the user,this paper provides a method using the time dimension to setup directly the time constant of filter,and gives out the functional relationship between the filter coefficient and the time constant.The MMI is therefore perfected considerably.