The 1747-BSN module serves as an interface between the SLC 500 processor and I/O devices connected to a DH+ network. It allows the processor to access data from remote I/O devices as if they were directly connected to the local I/O chassis.

The module supports various I/O types, including digital inputs and outputs, analog inputs and outputs, and communication modules. It supports up to 30 I/O modules in a single DH+ network.

The 1747-BSN module has a built-in DH+ network interface and requires configuration using Rockwell Software's RSLogix 500 programming software. It is typically installed in a remote I/O chassis and connected to the SLC 500 processor through a DH+ network cable.