Glossary · Industrial communication
PROFIBUS
Also known as: Process Field Bus, PROFIBUS DP, PROFIBUS PA
German: PROFIBUS
In industrial communication, PROFIBUS (Process Field Bus) is a fieldbus maintained by PROFIBUS & PROFINET International (PI), with the variant PROFIBUS DP for fast cyclic exchange with decentralized peripherals over RS-485 and PROFIBUS PA for process instruments over bus-powered two-wire cables, including hazardous areas.
- Industrial communication
- Standards
In one sentence
PROFIBUS is a PI fieldbus with PROFIBUS DP for factory automation over RS-485 and PROFIBUS PA for process instruments.
Example
A water treatment plant uses PROFIBUS DP to its motor control centers and PROFIBUS PA, via a DP/PA coupler, to its level and flow transmitters.
How it applies
- Engineering: PROFIBUS DP uses a master-slave model with station addresses, GSD files and bus segments limited by baud rate and length. Repeaters extend segments. PROFIBUS PA uses a different physical layer and needs couplers or links to DP.
- Commissioning: Termination at both segment ends, correct station addresses and the right GSD file versions are the main checks. Bus analyzers show signal quality and retries.
- Maintenance: PROFIBUS remains widespread in existing plants. Migration to PROFINET is often done step by step with proxies that connect PROFIBUS segments to PROFINET controllers.
- Documentation: The documentation team provides GSD files, the DP data image, supported baud rates, addressing instructions and the meaning of diagnostic bytes.
PROFIBUS vs. PROFINET
Both come from PI and share concepts such as GSD files and profiles, but PROFIBUS is a serial fieldbus and PROFINET is Industrial Ethernet. Devices of one can't be connected to the other without a proxy or gateway.