Allen-Bradley 1746-BAS-T-CC SLC 500 fixed or modular controller chassis with 2 configurable serial ports for RS-232/423, RS-422 & RS-485 communication with I/O devices
Allen-Bradley 1746-BAS-CC SLC 500 fixed or modular controller chassis with Two configurable serial ports for RS-232/423, RS-422, and RS-485 communication with I/O devices