Interfacing sensor with PLC

Hi all,
I have some online sensors for water quality measurements. Those sensors gives output as RS-485. I want to take these live sensor data to my beijer PLC. How can I do that?
I am attaching the sensor manual with this.
Online Turbidity Sensor Manual (1).pdf

Online Turbidity Sensor Manual (1).pdf

Can you please clarify how this question relates to PLCnext Technology?