Basically, the cables for RS 485 configuration are very common in the market, u can use 2 pairs X 18 AWG twisted, screen protection with drain-off wire. You will consider the class "A" communication or ring topology.
There probably lots of people who say to use specific types of wires for RS-485. In my experience with RS-485 I have found that pretty much any wire will work be it solid conductor or stranded wire, thick or thin. I've tried them all and as long as there is continuity in the wire it'll transmit.
