New Branch concept for EtherCAT

Thomas Rettig, senior management control system and communication architecture, at Beckhoff Automation, tells Food and Beverage Industry News about the latest news on EtherCAT from his company.

EtherCAT G and G10 are fully compatible with EtherCAT. Are there any special considerations that users might need to take into account?
Thomas Rettig: From a protocol point of view, EtherCAT G slaves will be able to operate easily with an existing EtherCAT master, provided the master is equipped with a 1 Gbit/s port. We are currently working on a number of EtherCAT G protocol extensions that will enable even better performance. There will have to be some extensions on the master side, but these will not be essential for network operation. Our new branch concept is being introduced to enable EtherCAT, EtherCAT G and EtherCAT G10 devices on a network to operate at different data rates (100 Mbit/s, 1 Gbit/s or 10 Gbit/s). Each branch connected to a branch controller represents a separate EtherCAT segment, and the EtherCAT segments can operate at different transfer rates and in parallel with one another. A few extensions in the EtherCAT master will make time- and bandwidth-optimised network operation possible.

Will the branch controller concept continue to support known EtherCAT features like processing on the fly and fully synchronised distributed clocks?
Thomas Rettig: These are both core features that have made EtherCAT such a success. EtherCAT G and EtherCAT G10 will both continue to support processing on the fly, as we already demonstrated live at SPS IPC Drives in 2018. The distributed clocks, too, will, of course, continue to be distributed for synchronisation across the branch controllers and will work in the same way as before.

Which applications already benefit from the higher bandwidth with EtherCAT G?
Thomas Rettig: The first application to benefit is our new XPlanar system. This transport system, with its planar motors, allows passive, levitating movers to be moved and positioned with six degrees of freedom and highest precision. It relies, however, on having plenty of available data bandwidth, and EtherCAT G meets that need perfectly. Similarly, any applications with high bandwidth requirements, such as machine vision cameras or high-precision measurement applications, will benefit. The branch controller approach also allows more complex EtherCAT networks to operate with shorter cycle times than were formerly possible because of limitations imposed by network size.

Will it be possible to connect EtherCAT G to TSN switches?Thomas Rettig:
Yes. The same applies to EtherCAT G as to EtherCAT. EtherCAT G is extremely efficient to integrate into a TSN environment. It requires minimal adaptation of the control system, no changes to slave devices, and just a minor extension in so-called open-mode devices used to connect EtherCAT slave segments to the TSN network.


When will your EtherCAT G products be available?

Thomas Rettig: We expect the FB1400 EtherCAT G piggyback controller for our EtherCAT evaluation board to be available in March 2019. This will give EtherCAT users and the makers of master and slave devices the chance to evaluate our new technology. The EK1400 EtherCAT G Coupler will follow in the fall of 2019. In our branch controller concept, the coupler makes it possible to use all of the Beckhoff EtherCAT Terminals and any other EtherCAT products in EtherCAT G networks. More products, including three- and eight-way branch controllers (CU1403, CU1418), an EtherCAT G junction (CU1423), an EtherCAT G10 branch controller (CU1468) and an EtherCAT G10 piggyback controller (FB1450), will follow in due course.