Omron CJ Series, Operation Manual

Page: 34 / 415

1-1 The CX-Integrator
1-1-4 Accessible Network
1-6
Local Network Table Requirements
A local network table must be registered in the target PLC in the following cases.
Communications Conditions
Network
communications
•
More than one Network Communications Unit is mounted to the target
PLC. (See note.)
Note: Network Communications Units include Ethernet Units, Controller Link
Units, SYSMAC LINK Units, DeviceNet Units, and FL-net Units. Serial
Communications Units and Serial Communications Boards are not
included except in the following case: If serial ports are registered in
the local network table to treat them as networks, the serial ports must
be treated as Network Communications Units, including the serial ports
on the CPU Unit.
•
Routing tables are already registered in one or more nodes on the network.
•
Communications are required between networks.
Serial
communications Serial ports on Serial Communications Units and Serial Communications
Boards are used as serial gateways to Host Link FINS and access is
required via networks via Host Link FINS to PLCs functioning as Host Link
slaves.
Note: Serial ports do not necessarily need to be registered in the local
network table (to treat them as networks) to enable using other serial
gateway functions. Registration is normally not required to convert from
serial to serial. Refer to
3-6 Overview of Serial Gateway Functions in
the CS/CJ-series Communications Commands Reference Manual for
details on whether local network tables are required to use serial
gateway functions.
Note: As an exception, local network tables are not required even when more than one Network
Communications Unit is mounted in the following situation:
Access is possible without a local network table when connecting online to the target PLC
via a direct serial connection and access is required only to the network of the Network
Communications Unit with the smallest unit number (set on the front panel rotary
switches) of all the Network Communications Units that are mounted to the target PLC.