The Design And Research In The Electrical Conductivity Instrument Based On Embedded System

Because sugar mills consume large amount of energy, so its energy saving is ofgreat significance. In recent years the sugar mills, energy saving have made someachievements, but still have some distance with the world advanced level. Recentlythe sugar mills energy project mostly focus on the recycle steam that come from theevaporator tank. When the manufacturing technique is normal, the one effectevaporator temperature is about120℃, the sugar content is below10ppm. the doubleeffect evaporator temperature is about80℃, the sugar content is below50ppm.According th boiler water standard, the sugar content shouid be less than50ppm.If the steam can reach this standard,the steam from the one effect evaporatoror the double effect evaporator can be used for the boiler.So the technology is thedetection of the sugar in the steam.This paper provide a method that measurement theelectrical conductivity of the steam in order to know the sugar content.This methodcan solve the problem.the experiments show that the relationship between the sugarcontent and its conductivity is positively correlated, approximately linear. So the keyto recycle the steam is to design a matching electrical conductivity instrument.In this paper, it is introduced an electrical conductivity instrument which basedon embedded system. This system chooses ARM Cortex-M3and C8051F350as thebasis of the hardware. Dual-CPU hardware makes the instrument have the capabilityof high accuracy and fast data processing. The system generates the sine wave whichis the excitation source base on DDS technology. In order to ensure the system hashigh adaptability, stability, anti-interference capability, optical-electrical isolationtechnology and independent power module technology are applied to this instrument.The system use RS-232and CAN bus communication interface to exchange the data.And at the same time the system use the USB interface to store the data.Modularization programming is used in this system software and the code program bythe C language. Software fitting is used in processing data. This method can easilydeal with the data and also very efficient.At present, the debug instrument mission has coming to the end. The systemhardware design, printed circuit board (PCB) manufacture and welding the electroniccomponents have been finished. And the software codes are also completed.