On the controller's top side, two RS-485 ports operate as COM1 and COM2. Each port is capable of up to 115,200 baud, and uses a 3-position, screw terminal connector.
Use shielded, twisted-pair, 18-22 AWG cabling to wire in a continuous daisy chain fashion to other RS-485 devices: minus-to-minus, plus-to-plus, and shield-to-shield. Connect the shield wire to earth ground at one end only.
For more information about wiring guidelines, refer to FX-PC Series Controllers MS/TP Communications Bus Technical Bulletin (LIT-12011670).
Callout |
Description |
---|---|
1 |
RS-485 port A (COM1) is often used to support a trunk of LP-FXRIO16-0 modules. Do not mix LP-FXRIO16-0 modules with other types of RS-485 devices on the same RS-485 trunk. |
2 |
RS-485 port B (COM2) supporting a network of other field devices using RS-485 field communication. |
3 |
RS-485 devices on the same network should use the same protocol and baud rate. Up to 32 or more devices may be supported depending on device specifications. |