Omron SYSMAC CS1W-SCB41-V1 Operation Manual page 247

Protocol Conversion
System Configuration Patterns
Sending FINS Messages Using CMND(490) in CPU Unit's Ladder Program
CPU Bus-to-Serial
Serial Communications Unit/Board
CPU Unit
Protocol
FINS header
conversion
Modbus-RTU
command
Modbus-RTU
Slave device
(e.g, OMRON
Inverter)
FINS message-to-Serial
FINS header
Serial Communications Unit/Board
CPU Unit
Protocol
conversion
Modbus-RTU
command
Modbus-RTU
Slave device
(e.g, OMRON
Inverter)
218
The Board/Unit converts the FINS messages to Modbus-RTU protocol for
sending in this operation.
Access from CPU Unit (on the Same PLC)
CMND(490)
FINS message
Modbus-RTU
2804
command
RS-485 (Modbus-RTU)
Access from CPU Unit (on Network PLC)
CMND(490)
FINS message
Modbus-RTU
2804
command
Network (Ethernet,
Controller Link,
DeviceNet)
RS-485 (Modbus-RTU)
Details
OMRON Inverters connected serially to
the Serial Communications Board/Unit
using Modbus-RTU can be accessed
from a CPU Unit in the same PLC.
Details
OMRON Inverters connected serially to
the Serial Communications Board/Unit
using Modbus-RTU can be accessed
from a CPU Unit in a PLC connected to
the network.
Section 6-5
Routing tables to
treat serial
communications
path as network
Optional
Routing tables
to treat serial
communications
path as network
Optional