Omron CJ Series, Operation Manual

Page: 157 / 415

3-1 Routing Table Overview
3-1-2 Network Conditions That Require Routing Tables
3-4
Setting Example
The following example shows the routing tables that route communications from PLC1
(network address 1, node address 1) to PLC4 (network address 3, node address 2).
PLC2 Local Network Table
Unit number Local network
address
0 1
1 2
PLC1 Relay Network Table
Destination
network
address (a)
Relay
network
address
(b)
Relay
node
address
(c)
2 1 3
3 1 3
PLC3 Local Network Table
Unit number Local network
address
0 2
1 3
The local network table shows that it is
necessary to pass through unit number
1 in the local CPU Rack To go to
network address 3.
Node address 1
(Unit number 0)
Node address 3 (Unit number 0)
Relay node PLC2
Local node PLC1
Network address 1
Node address 1
(Unit number 1)
Relay node PLC3
Node address 2
(Unit number 0)
Network address 2
Node
address 1
(Unit
number 1)
Target node PLC4
Node address 2
(Unit number 0)
Network address 3 (destination network)
PLC1 Local Network Table
Unit number
Local network
address
0 1
PLC2 Relay Network Table
Destination
network
address (a)
Relay
network
address
(b)
Relay
node
address
(c)
3 2 2
PLC3 Relay Network Table
Destination
network
address (a)
Relay
network
address
(b)
Relay
node
address
(c)
1 2 1
PLC4 Local Network Table
Unit number Local network
address
0 3
PLC4 Relay Network Table
Destination
network
address (a)
Relay
network
address
(b)
Relay
node
address
(c)
1 3 1
2 3 1
..1)
..2)
(a)
(b)
(c)
• To go to network address 3, first it is
necessary to go to node address 3 (c)
in network address 1.
•
Destination network (a) sets both
network address 3, and network
address 2, which must be passed in
order to reach network address 3.
1) Setting details
2) Setting details
(a)
(b)
(c)
• To go to network address 3, it is
necessary to go to node address 2
(c) in network address 2.
3) Setting details
..3)
(a)
(b)
(c)
• Destination network (a) sets
both network address 1 that has
a destination node of PLC4, and
network address 2, which must
be passed in order to reach
network address 1.
4) Setting details
..4)
(a)
(b)
(c)
• The destination network
address is set to network
address 1(a).
..5)
..6)
5) Setting details
6) Setting details
(a)
(b)
(c)
(a)
(b)
(c)
3-1-2 Network Conditions That Require Routing Tables
When necessary, set the routing tables (local network table and relay network table)
in the PLC as shown in the following table.
Routing table Network usage
Local network table Relay network table
One Communications Unit is mounted
in the PLC, and that Unit is connected
to one network. Not required Not required
Two or more Communications Units are
mounted to one PLC (CPU Unit). Required Not required
Routing tables have been set in at least
one other node in the same network. Required Not required
Communications are made across
network levels. Required Required
Routing Table Settings not Required
Routing tables are not required when just one Communications Unit is installed in
each PLC and those Communications Units are connected in a single network.
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