Glossary Updates12 new terms added to the glossaries · October 2, 2026, 22:44 CEST
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Glossary · Industrial communication

Fieldbus

Also known as: Field bus, Industrial fieldbus

German: Feldbus

In industrial automation, a fieldbus is a digital communication system that connects field devices such as sensors, actuators, drives and remote I/O with controllers, replacing individual parallel wiring. IEC 61158 and IEC 61784 standardize many fieldbus types and profiles.

  • Industrial communication
  • Standards

In one sentence

A fieldbus is a digital network that connects sensors, actuators and drives with controllers instead of individual parallel wiring.

Example

Instead of wiring 200 signals individually to the control cabinet, a machine uses a fieldbus to connect five remote I/O stations over one cable.

How it applies

  • Engineering: Choosing a fieldbus depends on controller platform, required cycle times, device availability, distance, and industry conventions. Most new installations use Industrial Ethernet systems, which are often counted as fieldbuses as well.
  • Commissioning: Every fieldbus needs addressing, device description files and a configured master. Network diagnostics tools shorten troubleshooting considerably.
  • Maintenance: Fieldbus diagnostics can pinpoint the failed device or segment, but only if the diagnostics are evaluated and shown to maintenance staff.
  • Documentation: The documentation team names the fieldbus and profile exactly, provides device description files and describes addressing, wiring rules and diagnostic indicators (for example LED codes).

Fieldbus vs. industrial Ethernet

Classic fieldbuses use dedicated serial physical layers (RS-485, CAN, two-wire). Industrial Ethernet uses Ethernet physical layers and often shares infrastructure with IT networks. IEC 61158 covers both kinds.

By knowledge.aitechdoc.world · Published September 26, 2026 · Last reviewed

Source: IEC 61158 (all parts), Industrial communication networks — Fieldbus specifications

Definitions follow the cited standards and specifications. Where a source is a copyrighted publication, such as an ISO, IEC or EN standard, the definition is a close paraphrase, not a verbatim quotation, so as not to infringe copyright. We recommend reading the original publication. The sections “How it applies” are editorial commentary by AI TechDoc Knowledge and are not part of any standard.

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