The Terminal enables within an EtherCAT Terminal network the integration of any CANopen devices and can either be master (EL6751) or slave (EL6751-0010). In addition, general CAN messages can be sent or received – without having to bother with CAN frames in the applications program. The terminal has a powerful protocol implementation with many features:

• All CANopen PDO communication types are supported: event driven, time driven (using an event timer), synchronous, polling.
• synchronization with the PC controller’s task cycle
• SYNC cycle with quartz precision for drive synchronization, zero cumulative jitter
• parameter communication (SDO) at start-up and when running
• emergency message handling, guarding and heartbeat
• powerful parameter and diagnostics interfaces
• online bus load display

Like the FC5101 CANopen PCI card, the EL6751 can be used for connection to CANopen networks. The terminal, however, enables a more space-saving implementation since no PCI slots are required in the Industrial PC.

https://www.beckhoff.com/vi-vn/products/i-o/ethercat-terminals/el6xxx-communication/el6751.html