An open real-time Ethernet Master/Slave network developed by Beckhoff for the industrial automation purpose. It is today an open standard that is managed by the EtherCAT technology group. New limits have been set by EtherCAT for real-time performance as it processes 1000 distributed I/O in 30 µs or 100 axes in 100 µs by using twisted pair or fiber optic cable. A simple low-cost line structure, a tree structure, daisy-chaining, or drop line with no expensive infrastructure components are supported by Ether CAT or a classic expensive star topology can also be used.
The transmission method of EtherCAT is also similar to the Interbus principles. The transmission process no longer receives the Ethernet packet. Ethernet packet is then interpreted and the data is processed and copied at every device. The reading of the data addressed to them is done by the EtherCAT slave devices while the frame passes through the device node. Also, the input data is inserted but the telegram passes through.
As the data from many devices are comprised of an EtherCAT frame both in send and receive direction, by 90% the useable data rate is increased. The feature of 100Base TX is full-duplex that can be fully utilized so that the effective data rate which is greater than 100Mbit/sec can be achieved.