Omron 3G8F7-CRM21, User Manual

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7
Network Construction Procedure Section 1-5
1-5 Network Construction Procedure
The following is the basic flow of a network configuration.
Examine the number of inputs and outputs on the entire system.
1) Decide the number of I/O points.
Assign each of these inputs and outputs to a Slave Unit.
2) Correspond the I/O points to Slave Units.
Decide the number of connected nodes.
3) Decide the number of nodes.
Decide the communications cycle in accordance with the number of
connectable Slave Units and the data rate. Examine if the required I/O
response time is obtained in the data rate.
6) Decide the communications cycle.
If re-examination of the communication mode number, the data rate and the
use of Repeater Units does not ensure the synchronicity of communication
cycle and distance, provide the CompoNet Master Boards in distributed
locations.
7) Examine the distribution of CompoNet Master Boards.
Decide following:
•
Wiring formation: Trunk line - Branch line formation or Unrestricted wiring
formation,
•
Wiring distance,
•
Methods to supply the communications power and the I/O power to the
Slave Units in less wiring effort, and
•
Cable type
4) Decide the wiring formation and installation.
5) Temporarily decide the number of connectable Slave Units
and the data rate.
See Appendix E:
Construction of a
CompoNet Network
See Appendix C:
Communications
Performance
Note The data rate of 4 Mbps does not support T-branch. Thus any Slave Unit
with pre-attached cables will not be usable.
See E.1.3 Maximum
Length and Maximum
Number of Connectable
Slave Units for Each
Type of Cables