Omron GRT1-ECT SmartSlice, Руководство по эксплуатации

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1 EtherCAT Network
1 - 2 GRT1-series EtherCAT Communication Unit - Operation Manual
1-1 Overview of EtherCAT Networks
EtherCAT (Ethernet Control Automation Technology) is a high-performance industrial network system
based on the Ethernet system that can realize fast and efficient communication.
Additionally, although EtherCAT is a unique communication protocol, it employs standard Ethernet
technology in the physical layer. Using standard Ethernet technology has advantages like decreasing
training needs and the use of commercially available Ethernet tools like cables.
EtherCAT can be used for large-scale control systems but also for small- and medium-scale
applications.
EtherCAT has the following features.
 Extremely high-speed communications with speed of 100 Mbps
It dramatically shortens the I/O response time from the generation of input signals to the
transmission of output signals. It makes the best use of the optimized Ethernet frame band, and
transmits with the high-speed repeat method, thereby allowing transmitting various types of data at
high efficiency.
 Employment of standard Ethernet technology
EtherCAT is a global open network that employs standard Ethernet technology in the physical layer.
For this reason, commercially available Ethernet cables, connectors, tools, and other
general-purpose products can be used.
EtherCAT does not transmit data to each node on a network, but gets Ethernet frames through each
node. At passing, each node reads and writes data in Units of several nanoseconds in its own area
within a frame.
Ethernet frames sent from the EtherCAT Master Unit go through all the EtherCAT Slaves without
stopping on the way. Once they reach the final Slave, they are sent back from the final Slave, pass
through all Slaves again, and return to the EtherCAT Master Unit.
With this structure, EtherCAT secures high-speed and real-time data transmission.
1-1-1 Features of EtherCAT
1-1-2 Structure of EtherCAT
EtherCAT
Master Unit
Slave Unit Slave Unit Slave Unit
Ethernet frame
IN OUT
Data
• Reading output data addressed to the local Slave Units
• Writing input data