Glossary · Industrial communication
EtherCAT
Also known as: Ethernet for Control Automation Technology
German: EtherCAT
In industrial communication, EtherCAT is a real-time industrial Ethernet system in which a single frame passes through all devices, and each device reads and inserts its data on the fly as the frame passes. It was developed by Beckhoff, is managed by the EtherCAT Technology Group and is included in IEC 61158 and IEC 61784-2.
- Industrial communication
- Standards
In one sentence
EtherCAT is a real-time industrial Ethernet in which each device processes the frame on the fly, allowing very short cycle times.
Example
A pick-and-place machine synchronizes 30 servo axes over EtherCAT with a cycle time of 250 microseconds using distributed clocks.
How it applies
- Engineering: EtherCAT uses one main device (master) and many subdevices (slaves). Distributed clocks synchronize the devices precisely, which suits motion control. Application protocols such as CoE (CANopen over EtherCAT) reuse existing device profiles.
- Commissioning: Devices are identified by position in the line or by an alias. The ESI file (EtherCAT Slave Information) describes each device to the configuration tool.
- Safety: Safety over EtherCAT (FSoE) transmits safety-related data over the same network using the black channel principle. The network doesn't become safety-rated; the safety devices at both ends do the work, and the Safety function must be validated as a whole.
- Documentation: The documentation team provides ESI files, the process data image and the device state machine behavior, and describes wiring order if device positions matter.
EtherCAT vs. PROFINET
EtherCAT processes one frame on the fly through all devices; PROFINET sends individual frames through switches, with IRT reserving time slots for isochronous traffic. Both reach short cycle times, but topology, tooling and diagnostics differ.