PROFIBUS
CX8030 / CX8031
73
Version: 1.6
9
PROFIBUS
9.1
System overview PROFIBUS
As a fast, open bus system with line topology and terminators, PROFIBUS is widely used in automation
technology. The PROFIBUS DP (Decentralized Periphery) variant for the fast exchange of data at sensor/
actuator level is internationally standardized according to IEC 61158, IEC 61784 and EN 50170.
In PROFIBUS DP, central control devices (e.g. Industrial PCs or PLCs) communicate via a fast serial
connection with decentralized input and output modules. RS485 is the most frequently used transmission
technique, using a screened twisted pair cable. Data is mainly exchanged cyclically, although acyclic
services (DP-V1) are available for parameterization and diagnosis.
PROFIBUS DP offers very short system reaction times: at a transmission rate of 12 MB, less than 2 ms are
required to transmit 512 bits each of input and output data to 32 devices.
All Beckhoff PROFIBUS devices feature a high-performance protocol implementation and are certified by the
PROFIBUS users organization (PNO).
