Allen-Bradley 1791-0B16 16 Output Block I/O Module

Product Overview

The Allen-Bradley 1791-0B16 is a discrete DC block I/O module from the 1791 Block I/O series. It provides 16 output channels and integrates essential elements such as a programmable controller interface, power supply, and signal-generating circuit. The 1791-0B16 eliminates the need for external power fusing thanks to its built-in internal fusing, simplifying installation and enhancing reliability.

Technical Specifications Breakdown

Key parameters for the 1791-0B16 are listed below for quick reference:

Industry Applications

Packaging Lines: The 1791-0B16 module's 16 discrete outputs can control actuators, solenoids, and indicators in high-speed packaging machinery. Its 0.5ms on-delay ensures rapid response for precise timing. The built-in fusing protects against overcurrent without external components, reducing enclosure space requirements.

Material Handling Systems: In conveyor networks, this block I/O module distributes control signals to remote zones. The 10-30V DC output range accommodates various industrial actuators. The module's ability to mount vertically or horizontally (vertical recommended) allows flexible placement in tight spaces.

Operator Interface Panels: For pushbutton stations and indicator lights, the 1791-0B16 provides reliable 24V DC outputs. The removable terminal strips simplify maintenance by eliminating rewiring during block replacement, reducing downtime in continuous operations.

Installation & Setup Guidance

Mount the 1791-0B16 module vertically for optimal thermal performance, though horizontal mounting is possible. When installing as the last block I/O module in a sequence, a termination resistor must be added to ensure proper communication termination. Use 2 mm² (14 AWG) solid standard wire with maximum insulation of 3/64 in. for wiring connections. The module contains two switch assemblies for setting the starting I/O group, I/O rack number, communication rate, last state, and last chassis. Set these switches according to your system configuration before powering up.

Maintenance & Reliability

Inspect the module periodically for signs of dust accumulation or loose connections. The built-in internal fusing eliminates the need for external fuse replacement, but verify that the power supply voltage remains within the 19.2-30V DC range. The maximum power dissipation of 12.5W (43 BTU/hr) should be considered when designing enclosure ventilation. For vertical mounting at 60°C, the output current rating is 500mA; for horizontal mounting at 60°C, it is 250mA. Ensure adequate airflow around the module to maintain reliable operation.

Compatibility & Integration

The 1791-0B16 is compatible with PLC-2, PLC-3, PLC-5/250, PLC-5 series, and SLC 5/02 series programmable controllers. It utilizes Universal Remote I/O communication for distributing I/O at remote locations. The module includes 1 COMM, 1 STATUS, and 16 I/O Status indicators for monitoring communication health and output states. When integrating, verify that the communication rate and rack number settings match the controller configuration.

Selection Guide & Purchasing Advice

When selecting the 1791-0B16 for your application, confirm that your controller supports Universal Remote I/O and that the 16 discrete outputs meet your load requirements. The module's 10-30V DC output range and 1mA minimum on-state current make it suitable for most 24V DC industrial loads. For purchasing, AutoDCSTech offers this component with detailed specifications to ensure compatibility. Please verify current lifecycle status and availability with AutoDCSTech before ordering.

Troubleshooting & Common Issues

If outputs do not energize, check the STATUS and I/O indicators. A lit STATUS LED indicates normal operation; if off, verify external power (19.2-30V DC) and communication settings. If an output fails to turn on, measure the output voltage at the terminal; a voltage drop exceeding 1V at rated current suggests a wiring issue or overload. For intermittent operation, inspect the removable terminal strips for secure connection. The maximum off-state leakage current is 0.5mA; if loads remain partially energized, verify that the leakage is within acceptable limits for your load type.