development begun back in 1987 in Germany, when 21 companies joined in order to create a standard for automated machines and other devices interfaces. The PROFIBUS FMS
was created first and followed by PROFIBUS DP
in 1993. At present days the PROFIBUS
is standardized by IEC 61158
and IEC 61784
. This communication bus is designated for a wide variety of automatization tasks.
Multiple industrial devices can be connected to PROFIBUS
. For example: Simatic
, and many others.
For this communication in the PROMOTIC system can be used:
- OPC server by other companies. The PROMOTIC application is then the OPC client
The usage of the PmaOpcDaClient object requires purchase of the "PmOPC" licence. With the freeware version PmFree, or when developing the application (with development environment for tersting purposes), this component is always functional.
Four interface types are used on the PROFIBUS
RS 485: For tasks where the high transfer rates are essential. The highest transfer rate possible is 12 Mbit/s. The devices are interconnected via the bus topology, using the A class cable (shielded twisted pair). At most 32 devices can be connected to one bus segment, the maximum number can be increased to 126 when using the repeaters.
RS 485-IS: It is a sparkle proof vetrsion of the RS485 interface. The maximum transfer rate is 1.5 Mbit/s. At most 32 devices can be connected to one bus segment.
MBP: (Manchester Coding and Bus Powered) A sparkle proof interface, the transfer rate of 31.25 kbit/s and device power supply using the bus conductor. The network topology can be either bus or star type. At most 32 devices can be connected to one bus segment in normal environment, or 10 devices in explosive environment. The data is coded by the Manchester code.
Optic fibers: enable very high transfer rates 12Mbit/s for very long distances (kilometers). The line, star or circle topology is supported. At most 126 devices can be connected in the network.