Modbus TCP UnitID
If a MODBUS TCP slave requires a slave address to be present (other than 255) in addition to IP Address, then this is the recommended workaround:
1.Add a TCP Gateway slave under CI867-Ethernet.
2.Declare (Insert) the slave as a Modbus Serial slave under the Gateway.
3.The TCP Gateway will then be having the IP address of the slave.
4.The Slave address (taken as the hardware position in the hardware tree) will be same as the address in the slave.
Note: Modbus Serial Slave position and Modbus TCP/IP Slave Device’s Slave ID, both should be same.
Example: If the Modbus TCP/IP Slave Device’s
IP is “192.168.50.56”
Slave ID is “3”,
Then Gateway IP should be “192.168.50.56”
Modbus Serial Slave Position should be 3 in the CEX Bus under the Gateway.
Important Note: This workaround is necessary only if the MODBUS TCP slave device actually listens/Checks for the slave ID.
Hope this will help you, thanks.