基于智能仪表和PLC的液位控制系统设计[1]

PLC

S7-300 PID
PLC
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Abstract
Nowadays intelligent measuring appliance is improving more and more quickly.It has been used in more an more place of our life.It can make Electric circuit much easier than before.And the control can be realized much more precise and convenient. Microelectronics and computer technology continues to develop, led to fundamental changes in the structure of instruments to micro-computer (single chip) as the main body, the computer technology and the organic integration of detection technology to form a new generation of "smart meters" in Measurement of process automation, measurement data processing and functional diversification of the traditional instrument, compared to conventional measuring circuit, tremendous progress has been made. PLC is a very useful control installment . It is widely used in a lot of control system in ourlives. It is the product of the computer,control,communication technology.It can make Electric circuit much easier than before.And the control can be realized much more precise and convenient.It very suits the control of water level. It will relay the traditional control technology, computer and communication technologies together with the control, and operation of flexible convenient, high reliability, suitable for continuous long-term characteristics of the work, very suitable for liquid level control requirements. This thesis mainly introduces a design of water level control system with intelligent measuring appliance,SIMATIC programmable logic controller (PLC) and configuration soft. This system adopts increment type Proportional-Integral-Differential arithmetic to realize the water level automation. For convenience to monitor the system and process data in actual time, we have designed Human Machine Interface HMI with configuration soft. The result of experimentation indicates that this system could run quickly, accurately and stably which accords with our aim perfectly. This system has been used widely in the temperature control system field for its low cost and high stabilization advantages. Experiment proved that the control system more satisfactory results, with more practical engineering value. Keywords: Water Level Control Intelligent measuring appliance PLC PID HMI
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