RS-485 Connections FAQ, 2 Wire RS485/RS232 - B&B Electronics Two switches are set for 2W or to the 2-Wire RS-485 Mode. Figure 3 applies to most B&B RS-485 Converters or Serial Cards that can be set for 2-wire or 4-wire operation, and for some 2-wire Converters that use the same circuit board for the RS-422 model. Check the Data Sheet schematic or block diagram. Wiring RS-485 Networks - Power Rich System PDF fileWiring RS-485 Networks Wiring Controlsoft RS-485 networks Operation Controlsoft RS-485 access control networks use the convention ‘+’ and ‘–’ to represent the lines ‘A’ and ‘B’, defined by the RS-485 standard1, respectively. Two-wire RS-485 networks operate in RS485 Recommended Wiring 2-Wire - farsite PDF fileRS485 Recommended Wiring . The following diagrams show the recommended schemas for 2-wire and 4-wire configurations for FarSync cards such as the FarSync Flex and FarSync T2Ee. 2-Wire . 4-Wire . Note: In addition to the data wires it is worth considering whether to use a shielded cable (Braid/Foil) connected to signal earth.