1791-16AC 1791 Block I/O 120V AC Digital Module | Allen Bradley

Product Overview

The Allen Bradley 1791-16AC functions as a self-contained, high-density Block I/O module designed for distributed control systems. It integrates 16 digital inputs and 16 digital outputs into a single, ruggedized chassis, operating at a nominal 120V AC. This module allows engineers to interface field devices directly with a Remote I/O (RIO) network, reducing the need for extensive wiring back to the main PLC rack. We supply this unit as 100% Brand New, providing a rare opportunity to secure original factory stock for maintaining legacy automation lines.

Technical Specifications

Engineering Advantages

• Consolidated Remote Architecture: The 1791-16AC combines the functionality of an I/O rack, power supply, and adapter into one block. This integrated design significantly reduces cabinet space requirements and simplifies field-level installations.

• Robust AC Signal Processing: The module manages high-voltage signals (120V AC) common in traditional motor control centers. It handles input on-state currents up to 12.3 mA, ensuring reliable signal detection even in electrically noisy industrial environments.

• Flexible Mounting and Cooling: This block supports both horizontal and vertical mounting orientations. Its thermal design dissipates up to 106.73 BTU/Hr, allowing for stable operation in standard industrial enclosures without specialized active cooling, provided adequate clearance exists.

• Legacy System Preservation: As an "Obsolete/Discontinued" model from the OEM, the 1791-16AC enables maintenance teams to repair existing systems without undergoing expensive and time-consuming migrations to newer platforms like Point I/O or FLEX I/O.

FAQs

• Is this 1791-16AC module truly new given its obsolete status?

  Yes. We guarantee this unit is 100% Brand New original factory stock. It arrives in its original Allen Bradley packaging with factory seals, ensuring the internal electronics have zero runtime hours.

• Can I use this module to replace other 1791 block variants?

  The 1791-16AC specifically handles 120V AC signals. You cannot directly substitute it for DC versions (like the 1791-16B) or versions with different point counts (like the 1791-8AC) without re-evaluating your field wiring and PLC I/O mapping.

• What are the wiring requirements for the inputs?

  The module organizes its 16 inputs into two groups of eight. You must ensure that each group shares a common neutral and that your input voltage falls within the 79–132V AC window to trigger a logical "On" state.

• Does this unit include the terminal blocks?

  Yes, the block I/O design features integrated terminal strips. Always verify your wire gauge and ensure secure connections to prevent arcing, especially given the 120V AC operational voltage.