Allen-Bradley 1791-0B16 24V DC Output Module Buyer's Guide

Product Introduction

When you need reliable remote I/O in packaging, material handling, or operator interface applications, the Allen-Bradley 1791-0B16 delivers. Part of the 1791 Block I/O series, this module integrates a programmable controller interface, power supply, and 16 output channels into a compact unit. It is cost-effective for mounting in smaller enclosures, reducing installation complexity and wiring costs.

Technical Specifications Breakdown

The 1791-0B16 operates on a nominal 24V DC supply. Its output voltage range spans 10-30V DC, and external power must be 19.2-30V DC. Each of the 16 outputs can handle up to 500mA at 60°C when mounted vertically, or 250mA at 60°C for horizontal mounting. The module draws 300mA from the backplane. Key performance metrics include a minimum on-state current of 1mA per output, a maximum on-state voltage drop of 1V at rated current, and a maximum off-state leakage current of 0.5mA. Output signal delay is 0.5ms on and 1.0ms off. The module dissipates up to 12.5W of power (43 BTU/hr). Built-in internal fusing protects against overcurrent, eliminating the need for external power fusing.

Industry Applications

This module excels in discrete automation tasks. In packaging lines, the 16 outputs control actuators, solenoids, and indicator lights directly from a remote location. For material handling systems, the 1791-0B16 distributes I/O near conveyors and sorters, reducing cable runs and simplifying troubleshooting. In operator interface stations, it provides reliable output control for pushbuttons and pilot lights. The module's compact size and flexible mounting options make it ideal for space-constrained enclosures.

Installation & Setup Guidance

Mount the 1791-0B16 vertically for best thermal performance, though horizontal mounting is acceptable with derating. Use 2 mm² (14 AWG) solid wire with maximum insulation of 3/64 in. for connections. The module features removable terminal strips that save maintenance time by eliminating rewiring during block replacement. Two switch assemblies set the starting I/O group, rack number, communication rate, last state, and last chassis. When the module is the last in a series, install a termination resistor to ensure proper communication. LED indicators include 1 COMM, 1 STATUS, and 16 I/O status lights for easy monitoring.

Compatibility & Integration

The 1791-0B16 communicates via Universal Remote I/O protocol, making it compatible with PLC-2, PLC-3, PLC-5/250, PLC-5, and SLC 5/02 controllers. It functions as a remote I/O node, distributing 16 output points at distances up to 10,000 feet from the controller. This integration reduces wiring costs and simplifies system expansion. The module supports both vertical and horizontal mounting in standard enclosures.

Selection Guide & Purchasing Advice

Before purchasing the 1791-0B16, verify your controller's compatibility with Universal Remote I/O and ensure your power supply delivers 19.2-30V DC. Confirm the required number of output points and mounting orientation to select the correct derating. For complete technical specifications, contact BluePLC Industrial. We stock the 1791-0B16 and can advise on availability and replacement options. Please verify current lifecycle status with BluePLC Industrial before ordering.