1791-IOBX | Allen-Bradley 1791 Block I/O 64-Input/64-Output 24V DC Module With Integrated Power Supply

The 1791-IOBX is a compact Block I/O module that integrates inputs, outputs, power supply, and communication interface into a single unit. It is designed for remote I/O applications in Allen-Bradley automation systems, simplifying wiring and reducing panel space. With 64 sinking inputs and 64 sourcing outputs, it supports large-scale digital I/O needs. It is typically used in distributed control architectures where decentralization of I/O is essential. Its built-in configuration switches and LED indicators aid in fast setup and diagnostics. The module is ideal for high-density industrial automation environments requiring both control and monitoring in one block.

The 1791-IOBX operates on 24 Volts DC nominal voltage. It accepts external power in the range of 18 to 26.4V DC, which is supplied via a dedicated terminal block. The device includes an internal power supply that distributes power to its internal circuits and I/O channels. It’s essential to maintain stable voltage within the specified range to ensure reliable operation. Proper grounding and wiring according to the manufacturer’s recommendations also improve long-term stability. Exceeding the rated voltage may result in module failure or communication errors.

Yes, the 1791-IOBX features a set of LED indicators for each input and output point, as well as status indicators for Power, Active, Communication, and Fuses. These LEDs allow for real-time monitoring of the module’s performance and operational state. There are also pushbuttons for selecting whether the display shows input or output status. These diagnostics are crucial during commissioning and maintenance, helping quickly identify issues such as blown fuses or disconnected wiring. The diagnostic features reduce system downtime and simplify troubleshooting.

Yes, the 1791-IOBX is fully compatible with Remote I/O (RIO) networks and is typically connected via Belden 9463 cable. It communicates with a master controller using the RIO protocol, enabling real-time data exchange. Configuration switches on the module allow you to define rack address, baud rate, processor restart behavior, and group assignment. It functions as an I/O adapter, processor interface, and power supply—eliminating the need for a separate chassis. Proper RIO configuration is essential for successful integration into the system.

No, the 1791-IOBX has been discontinued by Rockwell Automation and is no longer part of their actively supported product catalog. However, it may still be available through surplus channels or secondhand industrial equipment suppliers. Users with legacy systems still utilize the module due to its reliability and simplicity. Rockwell recommends migrating to newer I/O platforms such as the FLEX or POINT I/O systems for current applications. Despite its obsolescence, the 1791-IOBX remains in use in many installed systems and is documented for support purposes.