Intelligent Melt Pressure Transmitter System Design

In the industrial processes, the pressure is one of the important parameters in control system. Correctly measuring and control the pressure plays an indispensable role to guarantee security of the industrial control system and production process. So the pressure transmitter system has become an important part of many industrial control systems. In this paper, it will design an intelligent pressure transmitter system based on the microcontroller C8051F362which applies in high temperature melt extrusion control process. It adopts the metal resistance strain gauge pressure sensor as it is able to guarantee excellent continuous measurement stability and accuracy in the high temperature environment. This paper is consists of two parts, one is the analysis of the transmission system’s hardware circuit, it mainly consists of microcomputer control circuit, signal amplifier conditioning circuit,4～20mA/0～10V output circuit, display/keyboard circuit, alarm circuit hardware design, besides it designed RS-485communication interface which can communicate with the PC; another part is the voltage-pressure curve piecewise linear segmentation in order to improve the measurement accuracy, and using C and CPP language for the entire system software programming, so the software program has good readability and can be transplanted. In this paper, it uses the MFC designed a user-friendly operator interface at the PC terminal, so the staff can remotely observed to the real time pressure information through RS-485communication. Through the testing of the Bureau of Weights and Measures, it indicates the pressure transmitter system has excellent measuring accuracy and stability; it is able to meet the requirements of high temperature melt industrial process control.