外文翻译---基于现场总线监测系统的plc控制制造系统-plc设计(编辑修改稿)

外文翻译---基于现场总线监测系统的plc控制制造系统-plc设计(编辑修改稿)内容摘要：

ed to control the behaviors of the total winding system together with FX series PLCs of winding and unwinding system. The operating actions of the system and the sequence of these actions were edited beforehand into the control program by the designer. The control program sets a series of operations of the winding system, which tells the PLCs how to control a system. The current states of all sensors or actuators are saved as an array of input, output or flag signals in the PLC memory. Therefore, the PLC program is the basis of monitoring in a PLC controlled manufacturing system. The programming method used is the ladder diagram method. The PLC system provides a design environment in the form of software tools running on a host puter terminal which allows ladder diagrams to be developed,verified, tested, and diagnosed. First, the highlevel program is written in diagrams. Then, the ladder diagram is converted into binary instruction codes so that they can be stored in randomaccess memory (RAM) or erasable programmable readonly memory (EPROM). Each successive instruction is decoded and executed by the CPU. The fimction of the CPU is to control the operation of memory and I/O devices and to process data according to the program. Each input and output connection point on a PLC has an address used to identify the I/O bit. The method for the direct representation of data associated with the inputs, outputs, and memory is based on the fact that the PLC memory is organized into three regions: input image memory, output image memory, and internal memory[4]. The PLC program uses a cyclic scan in the main program loop such that periodic checks are made to the input variables. The program loop starts by scanning the inputs to the system and storing their states in fixed memory locations (input image memory). The ladder program is then executed rungbyrung. Scanning the program and solving the logic of the various ladder rungs determine the output states. The updated output states are stored in fixed memory locations (output image memory). The output values held in memory are then used to set and reset the physical outputs of the PLC simultaneously at the end of the program scan[4]. As we know, logic control is a remarkable property of PLC, and it can be applied to efficiently handle analog data[2]. 1) Analog data acquisition and transformation Analog inputs and outputs such as pressure and temperature need to be measured online. For instance, temperature is first acquired by the Platinum resistances. A signal transformation module then converts the measured resistance value into the voltage range of 15V. The output of this transformation module is finally collected and transmitted back to the above PLC. 2) PLC control algorithms The analog variables could be any controlled variable, ., temperature or pres。