What is Ethernet over EtherCAT?

What is Ethernet over EtherCAT?

”The communication protocol “Ethernet over EtherCAT” (EoE) is used to transfer process data as well as standard Ethernet communication. EoE is used, for example, to access the web server of an EtherCAT slave from an engineering PC. The Ethernet communication is tunneled through EtherCAT.

What is SDO and PDO in EtherCAT?

With CiA402, 2 types of Object Dictionary, SDO (Service Data Object) and PDO (Process Data Object), are available. PDO consists of a mappable Object Dictionary, and the process data content is defined by the PDO mapping. PDO is primarily used for cyclic communications to periodically replace the process data.

CAN you open EtherCAT?

CANopen over EtherCAT (CoE) allows the CANopen communication protocol to be implemented over an EtherCAT network, providing a user-friendly, cost-effective solution that provides deterministic data delivery along with faster transmission speeds over longer network lengths.


The CANopen protocol stack consists of different functions for different purposes. Process Data Object (PDO) is used to transmit the application data. The application data is transmitted without any protocol overhead in broadcast. Service Data Object (SDO) is used to gain access to all device parameters.

What happens when there is an error in the EtherCAT?

The EtherCAT startup is aborted, as well as the startup of the machine. This kind of error can appear anytime in the EtherCAT communication, typically when a cable is disconnected or cut or whenever an EtherCAT device is damaged. The master has a mechanism that detects such situations. An Error log is generated with the relevant information.

What is EtherCAT and how does it work?

In addition to being extremely fast and offering high performance, EtherCAT comprises a wide range of diagnostic features to help detect and isolate errors within the network.

What happens to EtherCAT when the network is cut?

An Error log is generated with the relevant information. The EtherCAT communication is aborted. If the network is cut, the drives on the side of the network disconnected from the master are moved into an error state ( F29 ). They are automatically stopped and powered off.

Why is the slave EtherCAT device not available?

The slave EtherCAT device does not exist or cannot be physically reached due to connector/cable failure. Slave is still busy with a previous command and is not ready. The controller generates an A31 alarm and logs a warning message when the WC values does not match the expected value.