Research And Accomplish On Water Consumption Information Acquisition System

On the background of practical engineering applications, the author makes attempt to expound entirely on the construction of the water consumption information acquisition system and the key technology about data acquisition ,data processing ,data communication and etc.In this dissertation, it is briefly introduced the basic theory of the water consumption information acquisition system and the type of communication. The water consumption information acquisition system have the peculiarity with peculiar sensor and were possessed of precision ,no accumulation error ,low consumption and etc.The system adopted the essential ideas of balance transferring and imbalance transferring ,meanwhile the author compares and analyses the popular used serial communication interface such as RS-232C,RS-485 and etc. In the distributed monitoring system the site sampler needs to communicate with upstream unit in order to realize the network management of data. RS-485 interface is widely used in the distributed system because of its particular advantage. Accordingly, the author clarifies detailedly some basic rules for RS-485 network links based on balance transferring from many aspects such as identity impedance,network topology,grounding,velocity and etc;discusses some protective measures in RS-485 network when the bus is open or short or free; analyses some unreliable factors in data transmission in the communication system consisting of many single-chip microcomputers using RS-485 chip as communication interface;studies some effective methods of improving the reliability of communication system from both hardware and software.