Communication in automation is becoming increasingly direct, horizontally at field level as well as vertically through all hierarchy levels. Depending on the application and the price, graduated, matching industrial communication systems such as the Ethernet-based PROFInet, the field bus PROFIBUS and other systems like the sensor/actuator bus AS-Interface offer the ideal preconditions for transparent networking in all areas and levels of the automation process.
At
sensor/actuator level the signals of the binary sensors and actuators are
transmitted via a sensor/actuator bus. Here, a particularly simple, low-cost
installation technique, through which data and a 24-volt power supply for the
end devices are transmitted using a common medium, is an important requirement.
The data are transmitted purely cyclically. AS-Interface is a suitable bus
system for this field of applications.
At field level the distributed peripherals, such as I/O modules,
measuring transducers, drive units, valves and operator terminals communicate
with the automation systems via an efficient, real-time communication system.
The transmission of the process data is effected cyclically, while alarms,
parameters and diagnostic data also have to be transmitted acyclically if
necessary. PROFIBUS meets these requirements and offers a transparent solution
for manufacturing as well as for process automation.
At cell level, the programmable controllers such as PLC and IPC
communicate with each other. The information flow requires large data packets
and a large number of powerful communication functions. Smooth integration into
company-wide communication systems, such as Intranet and Internet via TCP/IP and
Ethernet are important requirements.
The IT revolution in automation technology is
opening up new savings potentials in the optimization of system processes and
makes an important contribution towards improved use of resources. Industrial
communication systems have assumed a key function in this respect.
A detailed explanation of PROFIBUS as a central link in the flow of information
in automation is written in the correspondent section. For a description of
AS-Interface as an example for a sensor/actuator communication system, please
refer to the relevant literature. The extension of PROFIBUS technology to serve
as a cross-factory communication system on the basis of Ethernet is explained in
detail in the PROFInet section.
For further information on PROFIBUS visit the PROFIBUS website
Sorion Electronics Ltd.
Magreal Industrial Estate
Freeth Street
Ladywood
Birmingham
B16 0QZ