Safety over EtherCAT Specification
In the interest of realizing safe data communication over EtherCAT, the Safety over EtherCAT protocol (Fail Safe over EtherCAT, FSoE) has been disclosed within the EtherCAT Technology Group. EtherCAT is used as a single-channel communication system for transferring safe and non-safe information. The transport medium is regarded as a "black channel" and not included in safety considerations. A safety frame containing the safe process data and the required data backup is included in the EtherCAT process data. This "container" is safely analyzed in the devices at the application level. Communication remains single-channel. This corresponds to Model A from the Annex of pre-IEC 61784-3.
The Safety over EtherCAT protocol has been assessed by German Technical Inspection Agency (TÜV). It is certified as a protocol for transferring process data between Safety over EtherCAT devices up to SIL 3 according to IEC 61508. The implementation of the Safety over EtherCAT protocol in a device must meet the requirements of the safety target. The associated product-specific requirements must be taken into account.
The latest version of the ETG.5100 specification can be requested via email by ETG members only (click on description). Furthermore, please find all FSoE-related specifications listed as download below.
You may not copy, distribute or “mirror” these files or printed versions of the documents, or any part of it, without permission in writing from the ETG (EtherCAT Technology Group).
| Descrizione | Lingua | Tipo | Data | Dimensione | Ver. | Stato | |
|---|---|---|---|---|---|---|---|
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ETG.5100 Safety over EtherCAT Specification (request via email; for ETG members only) | EN | Mar 10, 2011 | 1.2.0 | Release (see also Errata sheet ETG.5100ES) | ||
| ETG.2200 EtherCAT SubDevice Implementation Guide | EN | Feb 05, 2025 | 5,41 MB | 3.2.0 | Release | ||
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ETG.5100 FSoE Specification Errata Sheet | EN | Feb 07, 2018 | 0,15 MB | 1.2.0 | Release | |
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ETG.5120 Safety over EtherCAT Protocol Enhancements | EN | Jan 24, 2023 | 0,48 MB | 1.3.0 | Release |
| Descrizione | Lingua | Tipo | Data | Dimensione | Ver. | Stato | |
|---|---|---|---|---|---|---|---|
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ETG.5120 Safety over EtherCAT Protocol Enhancements | EN | Jun 29, 2026 | 0,48 MB | 1.3.2 | Draft for Review |
You may not copy, distribute or “mirror” these files or printed versions of the documents, or any part of it, without permission in writing from the ETG (EtherCAT Technology Group).







