Omron 3G3AX-MX2-ECT User Manual

1 EtherCAT Network
1 - 4
EtherCAT Communication Unit USER’S MANUAL (3G3AX-MX2-ECT)
In EtherCAT, data is not sent to each node in the network, but the Ethernet frame is made to pass
through each node.
As the frame passes through, data is read and written at each node in the node's own area inside the
frame in several nanoseconds.
The Ethernet frame that was sent by the EtherCAT master passes through all the EtherCAT slaves
without stopping midway. Then, the frame is sent back by the final slave, and passes through all the
slaves again before returning to the EtherCAT master.
This system ensures high-speed data transmission and realtime performance.
The periodic data exchange between the EtherCAT master and EtherCAT slaves is performed with the
"EtherCAT telegrams" that are stored directly inside the Ethernet frame.
Each "EtherCAT telegram" consists of an address, data and working counter (check bit) for one or more
slaves.
If we compare an Ethernet frame to a train, EtherCAT telegrams can be considered as the carriages.
1-2-2 EtherCAT System
EtherCAT master
Slave Slave
Slave
Ethernet frame
IN
OUT
Data
• Reading of output data addressed to self
• Writing of input data
Ethernet
header
CRC
Ethernet data (Max. of 1,498 bytes)
Data
Datagram
header
WKC
1…n EtherCAT telegram
EtherCAT
header
1st EtherCAT
telegram
2nd EtherCAT
telegram
n th EtherCAT
telegram
. . . . .
Ethernet frame
Ethernet frame
WKC: Working counter

Omron 3G3AX-MX2-ECT Specifications

General

Brand	Omron
Model	3G3AX-MX2-ECT
Category	Controller
Language	English