Safety over EtherCAT (FSoE)

Safety over EtherCAT (FSoE) is a safety protocol that carries safety-critical process data in safety containers over EtherCAT or other underlying communication systems. It uses a Black Channel approach, so the standard communication path is not considered safety-relevant. It is developed according to IEC 61508, standardized in IEC 61784-3, and supports safety applications up to SIL 3.

Source checked7/7 values · 2026-10-25

Specification

1 source

Transports	ethernet l2, other
Architecture	master slave
Encoding	binary
Standard body	IEC
Standard ref	IEC 61784-3

Data types

Name	Description
Safety Container	Contains safety-critical process data and additional information used to secure this data; transported as part of process data.

Study notes

FSoE stands for FailSafe over EtherCAT.
Safety containers contain safety-critical process data and additional information used to secure the data.
Safety containers are embedded in the cyclical communication's process data.
A single EtherCAT channel can transfer both standard and safety-critical data.
Safety containers can travel through fieldbus systems, Ethernet, copper cables, fibre optics, and wireless connections.
In robotics, FSoE is used for safe motion control in an 8-kHz closed loop.
Safety over EtherCAT frames can be routed via the EtherCAT Automation Protocol (EAP) on the process control level.
Implementing FSoE in a device is stated to require little resources and can provide short reaction times.

Safety

The EtherCAT safety technology was developed according to IEC 61508.
It is approved by TÜV Süd Rail.
It is standardized in IEC 61784-3.
The protocol is suitable for safety applications with a safety integrity level up to SIL 3.
The communication system operates as part of a Black Channel and is not considered safety-relevant.