A Design And Implementation Of Measure And Control Module Of Temperature And Humidity

Human survival and development is closely related to temperature and humidity. Withthe rapid development of technology and extremely abundant in products, and producinghigh-quality products depends on a stable and reliable environment of temperature andhumidity in a large extent, the requirement of all walks of life on temperature a nd humidity isbecoming more and more strict. There for, an efficient and reliable measurement and controlof the production workshop and the storage environment is in an urgent need, which has greatsignificance for the development of human beings.Traditional control of temperature and humidity depends too much on man power andartificial detection, the way to obtain the parameters of temperature and humidity is throughhuman’s observation and record by turns, which leads to poor efficiency and low accuracy.There are many defects and shortcomings for relying on artificial measurement and controland we can see that many major loss and accidents are caused by human factors in old days.Now, under the background of great development of each field, especially the development ofsensor technology makes accurate measurement and control become possible. It has a trendthat all areas will be run in a way of automation control.With the help of analysis of data by single-chip microcomputer, the data that is obtainedby the measurement of sensors, we can now make timely and correct judgments easily tocontrol the temperature and humidity accurate. Thus greatly improve the control precision andliberating the manpower. However, we are late into the study of measureme nt and control oftemperature and humidity in our domestic compared with abroad, and there is quite a longway to go to catch on the level of measurement and control abroad. So it is necessary andurgent for us to research on a measurement and control system of temperature and humiditywith high precision, low cost, anti-jamming, high stability.The purpose of this paper is to establish a distributed measurement and control system oftemperature and humidity, which is on the basis of various reliable techno logies in nowadays,and it will be of integration, automation, networking and low cost.The distributed measurement and control system of temperature and humidityestablished in this paper is based on the modular design method. The whole measurement andcontrol system can be divided into the monitor module on PC, the measurement module, theswitch control module, RS485serial communication module and the mobile client applicationmodule. The control process such as heating control, spray control and flap co ntrol is based on a certain benchmark and the analysis of periodic acquisition of key parameters oftemperature and humidity in Arduino microcontroller. For a more efficient control of theproducing and the storage environment, the user of this system can switch the control systemcompulsorily if needed.Based on the Arduino hardware platform, this measurement and control system gets itshigh-accurate, reliable temperature and humidity parameters at the minimum cost by using themeasurement method of3-wire Pt100platinum resistance temperature detector, which is akind of high precision method commonly used in industrial environments. For a Pt100RTD,3-wire measurement method can produce a value for temperature. We calculate the relativehumidity based on the theory of measuring humidity which has used two Pt100RTD as thedry-bulb and wet-bulb. Then, according to the temperature, humidity parameters obtained,Arduino microcontroller analyzed and carried out based on a certain benchmark so as tocontrol the environment.Data communication is performed on the RS485serial communication bus, which isconnected with measurement and control system of temperature and humidity distributed,with the RS485serial communication bus, the communication of this system can be moreeffective, reliable and robust. Besides, with the help of the mobile client, the users of thissystem can have a timely access to the current state of the measurement and controlinstruments of temperature and humidity, and make remote control possible for users.