RS-485 half-duplex wiring example

This shows how to connect a single device, but RS-485 half-duplex networks are the most common multi-drop configuration. If wiring for multiple devices, make the three wire connections in parallel, similar to that shown in the full-duplex multi-drop example.

NOTE:

As with all RS-485 configurations, the use of termination resistors is optional. They tend not to be required with shorter cable runs and with modern slew-rate-limited driver technology (as used in the SDM‑SIO2R).