The Allen-Bradley 1772-SD Remote I/O Scanner is an electronic device that serves as a distribution panel for enabling the communication of the Bulletin 1772 PLC-2 Mini programmable logic controllers with up to 896 Iinput and output points (also known as I/O points). This distribution panel collects all the wiring coming from the sensors and going to the actuators installed in the same field, and it establishes a communication link between them and a Remote I/O Adapter Module (cat. no. 1771-AS) that is located in a separate control room or panel board, via a Twinaxial Cable (cat. no. 1770-CD). The distance between the 1772-SD Remote I/O Scanner and its corresponding 1771-AS Remote I/O Adapter Module can extend to 10,000 feet (3048 meters) maximum.

Using an Allen-Bradley 1772-SD Remote I/O Scanner in an industrial process will allow the final users to feed PLC-2, PLC-2/20, and PLC-2/30 processors with input data from the field. Then the processors will determine automatically the next actions to be taken in an application and send a response through the 1772-SD I/O Scanner, telling the actuators in the field what to do. An external power supply module (cat. no. 1771-P1) provides the voltage levels that are needed for the 1772-SD Remote I/O Scanner to operate. Like all the members of the Bulletin 1772 family, the Allen-Bradley 1772-SD Remote I/O Scanner is suitable for panel mounting. The operating temperature of the Remote I/O Scanner 0 to 60 degrees Celsius (32 to 140 degrees Fahrenheit). Environmental protection against water, dirt, debris, or other contaminants that may be present at the application´s job site should be provided by the users in the form of a suitable enclosure.