The 1791 Block I/O series is a series of small I/O devices that each include a power supply, a programmable controller interface, input and output connections, and circuitry. These devices come in small and compact designs. They have been designed and distributed by Allen-Bradley. The Allen-Bradley 1791 Block I/O series devices include 2 different kinds of blocks, and these are the 1791-IOBA block that comes with 8 inputs and 8 outputs, and the 1791-IOBB block that has 10 inputs and 6 outputs. The specifications are the same for both devices. These 2 blocks are compatible with different programmable controllers from the Allen-Bradley PLC-2, PLC-3, PLC-5, and the SLC 500 families of controllers. Physically, these blocks are composed of a DH-485 port, switch assemblies, status indicators, communication and power LEDs, removable remote I/O connectors, and removable input and output connectors.
The Allen-Bradley 1791 Block I/O devices provide all the functions of different equipment in a single terminal. These include the functions of an I/O rack and module, adapter, and a power supply. Both blocks require a 24 Volts DC power supply that has current limiting capabilities. The voltage that is employed must not fall outside the range of 20.5 to 27.6 Volts DC. The Allen-Bradley 1791 Block I/O must be installed in a ventilated area. This must be done to avoid overheating and enable the blocks to have safe operations. A minimum of 2 inches must be left between different blocks and the air temperature between the blocks must not exceed 55 degrees Celsius. The blocks must be mounted horizontally.
Browse available units in our catalog of 1791 Block I/O.