PROFIBUS

PROFIBUS (Process Field Bus) was originally a standard developed by Siemens for fieldbus communication in automation technology. In 1987, a consortium of over 20 institutions and companies was formed to establish a unified standard for a bit-serial fieldbus.

The standardization of the field device interface would later lay the foundation for the use of the fieldbus in manufacturing, process, and building automation. This required a common and uniform technical concept, as well as a communication model. Thus, PROFIBUS was standardized in the international IEC 61158 series of standards.

PROFIBUS is a multi-master system that enables the simultaneous operation of multiple systems with decentralized peripheral devices on a single bus. The protocol architecture is based on recognized international standards—in this case, it follows the OSI (Open System Interconnection) reference model, in accordance with the ISO 7498 standard.

Each transmission layer performs precisely defined tasks. Layer 1 (Physical Layer) defines the transmission physics, Layer 2 (Data Link Layer) the bus access protocol, and Layer 7 (Application Layer) the application functions.

The PROFIBUS fieldbus standard has been gradually expanded to include new application areas in recent years, with PROFIBUS DP being the most widely used variant.

PROFIBUS Device Types

Master-Devices

The master is a so-called “active participant” that controls all data traffic on the bus. It is the only device authorized to access a resource without being requested to do so and to send messages without an external request.

Slave-Devices

Slaves, on the other hand, are “passive participants” that do not have independent access rights to the resource. They must be explicitly requested by the master to access the bus.

PROFIBUS Protocol Variants

PROFIBUS DP (Decentralized Peripherals)

… for communication between central automation devices and decentralized field devices via a serial connection. Technical advancements include PROFIBUS DP/V1 and PROFIBUS DP/V2.

PROFIBUS PA (Process Automation)

… which is primarily used in the field of process engineering, is responsible for communication between measurement and process devices or between actuators and process control systems.

PROFIBUS FMS (Fieldbus Message Specification)

… was originally designed for use in automation technology for complex machines and systems. Today, this variant is gradually being replaced by PROFIBUS DP.

Nevertheless, we continue to offer communication and diagnostic solutions for the entire PROFIBUS protocol family.