Allen-Bradley 1746-BAS SLC 500 Basic Module 2-Port DH485

The Allen-Bradley 1746-BAS SLC 500 Basic Module is a three-serial-port interface card for the SLC 500 family, delivering a dedicated DH485 network port plus two user-programmable serial ports (PRT1 and PRT2). The PRT1 and PRT2 channels support RS-232, RS-422, and RS-485 signaling and can be configured for DF1 communications, enabling direct connections to third-party devices such as printers, serial modems, or other controllers. A separate DH485 port links the SLC 500 controller to a DH485 network for multi-node communication with compatible devices. As a BASIC language module, 1746-BAS executes user programs on the SLC controller and serves as a bridging interface between the controller and external serial equipment. In operation, if PRT2 is configured for DF1 or used for a DF1 interface, the DH485 port is disabled, reducing network connectivity. Catalog Number 1746-BAS denotes this legacy SLC 500 BASIC module used in older installations and typically installed in an SLC 500 chassis with the appropriate backplane power considerations.