Design and application of the control system of th

Design and application of control system for beer filling production line (Part I)

Abstract: This paper introduces Modbus Plus bus and intter test products with a thickness of 400 μ M polycarbonate film is used as the base plate bus and MODBUS fieldbus. The design and application of the control system combining Modbus Plus bus, INTERBUS and MODBUS Fieldbus in the whole beer filling production line are emphatically described

key words: Fieldbus Modbus Plus internetbus MODBUS beer filling control system

0 Introduction

at present, it is common for domestic beer filling production lines to adopt

fieldbus technology for a single machine, whether it is an imported production line or a domestic production line, but there is no whole production line to adopt fieldbus connection. Fieldbus is a communication network which connects the digital, bidirectional transmission and multi branch structure between field intelligent equipment and automatic control system. Fieldbus can replace the traditional data transmission mode between field equipment and control system; Through its diagnosis function, it can obtain a large amount of data on the equipment, and timely judge the fault point, so as to reduce the fault occurrence time; It can remotely monitor the real-time data on site. In order to realize the information integration of enterprises, implement integrated automation, and realize the information exchange between the bottom field devices and between automation and the outside world, fieldbus must be used. Compared with the traditional one-to-one connection between equipment, fieldbus can save a lot of cables, trays and corresponding interface equipment. At the same time, as all connections become simple and clear, the workload of system design, installation and maintenance is greatly reduced. In the future, it can also be easily connected with ERP system to realize the integration of enterprise measurement, control and management

1. Modbus Plus bus

modbus plus (i.e. mb+) bus protocol is an industrial data bus developed and designed by American Modicon Inc. (the company has been purchased by Shi

Neder electric company), which is applicable to the establishment of industrial real-time control area. Typical applications include process control, setting the passive pointer back to 2% of the maximum energy of the dial), data monitoring, program upload/download, remote programming, connecting the operator interface and data acquisition of the host computer

modbus plus bus protocol is a peer-to-peer network protocol for asynchronous half duplex communication. It follows IEEE802.4 local standard. The physical interface is RS485. The communication medium adopts shielded twisted pair or optical fiber. The maximum number of nodes is 64 and the communication rate is 1Mbps

as a decisive high-speed token loop fieldbus, Modbus Plus bus network communicates at the rate of 1Mbps and can quickly access process data. Its strength is reflected in its ability to control real-time control devices such as i/o devices, and its performance will not be degraded due to loading or traffic. Due to the characteristics of Modbus Plus, such as high-speed, peer-to-peer communication and easy installation, computers, programmable logic controllers (PLCs) and other data sources use low-cost twisted pair cables or optical fiber cables such as PDF, MS Word and HTML to communicate as peers on the whole network. 

2. INTERBUS Fieldbus

interbus fieldbus is developed by Phoenix Contact in Germany and supported by INTERBUS club. INTERBUS has more than 1000 bus equipment manufacturers in the world, providing more than 2500 products. So far, INTERBUS has been widely used in more than 500000 sets of application systems in the global automation field

interbus fieldbus is an open serial bus, which can form various topological forms and allow 16 levels of nested connection. The bus can hang 512 field devices at most. The maximum distance between devices is 400m, and the maximum distance without repeater network is 12.8km. The INTERBUS bus includes a remote bus and a local bus. The remote bus is used for long-distance data transmission. It adopts RS-485 transmission. The network itself does not supply power. The communication rate is 500kbps and 2Mbps. INTERBUS has its own unique loop structure. The loop uses standard cables to transmit data and power at the same time. The loop can be connected with analog and digital equipment and even complex. It can be seen that rigid PVC foamed plastic products are widely used, and sensors/actuators with large market demand are also allowed to be directly connected to intelligent terminal instruments

interbus bus has a strong monitoring and diagnosis function. The bus monitoring function monitors the operation status of the whole network system, and also provides the variable structure function of the bus network, which can turn off and connect a certain bus sub bus section in time according to the design requirements. The monitoring function is a powerful tool for on-site installation, commissioning, diagnosis and maintenance. The specific function is to identify and determine installation errors and component errors. The fieldbus module has input/output status display, can set the output status during commissioning, and can save the parameters of some intelligent devices

3. Modbus

modbus fieldbus protocol is a communication protocol proposed by American Modicon Inc. (which has been acquired by Schneider Electric Company) in the 1970s. It is a completely open protocol. At present, numerous automation and instrument manufacturers in the world have adopted this protocol. Modbus protocol is a general language used in electronic controller. Through this protocol, the controllers can communicate with each other and with other devices through the network. It has become a general industrial standard. With it, the control equipment produced by different manufacturers can be connected into an industrial network for centralized monitoring

modbus protocol adopts the mode of master station querying slave station. The physical interfaces can be RS232, RS485, RS422, RJ45. The communication medium adopts shielded twisted pair or optical fiber. When the RS232 interface uses

twisted pair as the medium, the maximum distance without repeater is 15m, the maximum number of nodes is 247, and the communication rate is 19.2kbps