What is the meaning of the plc station number in the text op320 editing screen?

This is applied to one screen multi-machine, one screen connects N PLCs in parallel through RS485, the station number of the first plc is 1, the station number of the second plc is 2 and so on (this station number needs to be set in plc ), so that you can set up, monitor, and control multiple PLCĀ  in one display.