Do you have a USB to RS485 converter? You will need that in order to configure the I-7018 module using the DCON utility.
Basically you use a PC to configure the I-7018 via the RS485 port. The main purpose is to configure it to the correct baud rate settings as that of the PLC (default is 38400, 8, 1, n for the PLC but 9600, 8, 1, n for the I-7018). If you only have one I-7018 module then you can keep the default ID. If you have more than 1 I-7018 then you will need a different ID for each module.
Once you have configured the DCON to be the same baud rate as the PLC, then you simply connect the RS485+ of the PLC to that of the I-7018, and similarly for the RS485-. Assuming the I-7018 and PLC share the same 24V power supply that's all the connection that is required (two wires).
However, if the I-7018 and the F1616-BA are using different power supply then you should connect their 0V together to provide a common ground.
You can then refer to the sample programs in the following i-TRiLOGI folder:
C:\TRiLOGI\TL6\usr\samples\I-7000
Inside this folder you should find the sample program I-7018.PC6 which you can transfer to the PLC and then observe for the response from the I-7018 and the value displayed on the PLC's LCD (if you don't have the actual LCD you can go online monitoring of the PLC and click "View" button to see the virtual LCD on the online monitoring screen.
If there is problem in the communication, you can connect the USB-RS485 converter to the RS485 pairs and run a terminal emulation software (e.g. RealTerm) to monitor the communication. Since the COMM is via ASCII text you can see what the commands sent from the PLC and check for the response from the I-7018.