Omron 3G8F7-CRM21, Руководство пользователя

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Overview of the CompoNet Network Section 1-1
1-1 Overview of the CompoNet Network
CompoNet is a field network designed for communications between the input
and output components on the shop floor and a personal computer (or PC) or
a PLC. CompoNet requires less wiring labor but provides high maintainability.
The PC and the CompoNet Slave Unit exchange input and/or output data
cyclically through a CompoNet Master Board.
By using explicit messages, users can read data from the CompoNet Slave
Unit or write data into it.
Here are the main features of CompoNet:
High-Speed
Communications of
Multiple Nodes CompoNet can provide remote I/O communications for multiple nodes as
many as maximum 2,560 points in a high speed such as 1000 points per
millisecond when the data rate is 4 Mbps*. This allows integration of
conventional system configuration with basic I/O Units into a CompoNet
network.
* The data rate of 4 Mbps does not support T-branch connection. Thus any
Slave Unit with pre-attached cables is not usable.
Greater Flexibility with
Repeater Units Repeater Units can expand a network installation in the following ways:
• Extending the Communications cable,
• Increasing the number of connected nodes,
• Creating a branch connection from the trunk line, and
• Converting cable types.
Repeater Units can be used to expand the trunk line for up to two layers. The
lines downstream from the Repeater Units are called sub-trunk lines. The
maximum number of connectable Repeater Units is 64 per Master Board and
32 per trunk line.
Note The power to the sub-trunk lines must be supplied from the Repeater Units.
Slave Unit
CompoNet Master Board
Terminating
Resistor
Terminating
Resistor
Terminating Resistor
Repeater
Unit
Repeater Unit
Slave Unit
Slave Unit
Slave Unit