IDPG 940128102 ABB

IDPG 940128102 ABB

Industrial Ethernet – Standard for area and cell networking, up to 1024 stations 1.5km(electrical network) or 200km(optical network).

In this network system, especially worth mentioning is PROFIBUS fieldbus, PROFIBUS is one of the successful fieldbuses at present, has been widely used. It is not dependent on the manufacturer, open fieldbus, a variety of automation equipment can be changed through the same interface. A large number of manufacturers provide PROFIBUS products, users are free to choose the right product. PROFIBUS has become the German national standard DIN192 and the European standard pr EN50170, and has a large number of users in the world.

Four, PLC and industrial control computer (IPC) and distributed control system (DCS) comparison

1. Origin of respective technological development

A computer is a device designed to meet the requirements of fast and large data processing. In terms of hardware structure, the bus has a high degree of standardization, strong compatibility, rich software resources, especially the support of real-time operating system, so it has an advantage in the control of industrial objects that require fast, real-time, complex models and large computational workload.

Distributed system from industrial automation instrument control system to industrial control computer as the center of the distributed system, so it has certain advantages in analog processing, loop regulation, the initial mainly used in continuous process control, focusing on loop regulation function.

PLC is developed from the relay logic system, mainly used in discrete manufacturing, process control, the initial is mainly to replace the relay control system, focusing on the switching quantity sequence control.

In recent years, with the development of microelectronics technology, large-scale integrated circuit technology, computer technology and communication technology, PLC has made a leap in technology and function. On the basis of the initial logic operation, the functions of numerical operation and closed-loop adjustment are added, and the function modules of analog and PID adjustment are added. The computing speed is increased, and the ability to catch up with industrial control computers; The improvement of communication capability has developed a variety of local buses and networks (Lans), which can also be constituted as a distributed system. In particular, personal computers have also been absorbed into PLC systems.

The development of PLC in process control will be an intelligent transmitter and fieldbus, and extend the function downwards and open the bus.

In the context of the development of microelectronics technology, from the point of view of the degree of hardware, the difference between PLC, industrial computers, distributed systems (DCS) is narrowing, and will be composed of similar micro-electronic components, microprocessors, large-capacity semiconductor memory and I/O modules. There are many similarities in programming.