Proface PS4800 - 19 Panel PC" - Manual (Page 106)

Industrial Personal Computer Connections
106
RS-485 - Bus length and cable type
The maximum transfer rate of 115 kBit/s depends on the cable type being used.
The material used for the cable should preferably have all or most of the following properties
in order to reach an optimal transfer rate.
Distance [m] Transfer rate [kBit/s]
1200 Typ. 115
RS-485 cable Property
Signal lines
Cable cross section
Wire insulation
Conductor resistance
Stranding
Shield 4 x 0.25 mm² (24AWG/19), tinned Cu wire
PE
≤ 82 Ω/km
Wires stranded in pairs
Paired shield with aluminum foil
Grounding line
Cable cross section
Wire insulation
Conductor resistance 1 x 0.34 mm² (22AWG/19), tinned Cu wire
PE
≤ 59 Ω/km
Outer sheathing
Material
Characteristics
Entire shielding PUR mixture
Halogen free
From tinned cu wires