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
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WKC
1…n EtherCAT telegr
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2nd EtherCAT
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n th EtherCAT
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. . . . .
Ethernet fr
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Ethernet fr
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WKC: Working co
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Summary of Contents for 3G3AX-MX2-ECT
Page 23: ...20 EtherCAT Communication Unit USER S MANUAL 3G3AX MX2 ECT CONTENTS ...
Page 31: ...1 EtherCAT Network 1 8 EtherCAT Communication Unit USER S MANUAL 3G3AX MX2 ECT ...
Page 85: ...4 Inverter Control 4 18 EtherCAT Communication Unit USER S MANUAL 3G3AX MX2 ECT ...
Page 111: ...5 CiA402 Drive Profile 5 26 EtherCAT Communication Unit USER S MANUAL 3G3AX MX2 ECT ...
Page 162: ...Index 1 EtherCAT Communication Unit USER S MANUAL 3G3AX MX2 ECT I Index ...
Page 164: ......