The Allen-Bradley 1791-24B8, also cataloged as the 179124B8 Block I/O Module, operates as a dedicated hardware component for discrete signal acquisition and actuation within industrial control networks.

Suffix Breakdown and Variant Designations

• 1791-24B8: Base catalog designation for the standard 32-point block I/O unit.
• 179124B8: Alternative numeric representation used for internal cataloging and spare parts inventory tracking.
• 1791-24B8/B: Revision B hardware build incorporating updated onboard filtering and terminal block layout configurations.

Hardware Technical Specifications

Industrial Control and Network Architecture

Configured for deterministic fieldbus architectures, the module executes discrete logic interfacing across Allen-Bradley remote I/O topologies. The internal architecture manages high-density signal distribution by decoupling input power grouping from output switching channels. The unit processes field signals through optical isolation barriers to protect backplane communication buses from transient voltage spikes. Firmware flash compatibility ensures integration with legacy and transitional controller operating systems without requiring hardware replacement.

Standard Package Contents

• 1 x 1791-24B8 Block I/O Module
• 1 x Removable Screw Terminal Block Set
• 1 x Hardware Installation Instruction Sheet

Field Mechanical Deployment Guidelines

• Mount the module securely onto a standard DIN rail or directly to a backplate using designated mounting screw clearances.
• Ensure clear physical spacing around the enclosure perimeter to facilitate passive thermal dissipation during continuous operation.
• Route high-voltage power lines and low-voltage signal cables through separate metallic conduit trays to minimize electromagnetic interference.
• Torque terminal block screws to manufacturer-specified limits to prevent intermittent contact resistance under vibration.

Frequently Asked Questions

• What is the total point capacity of the module?

  The module provides 32 total points, segregated into 24 inputs and 8 outputs.

• How are the input points configured internally?

  The 24 inputs are divided electrically into 3 isolated groups of 8 points each.

• What is the operational voltage range for the outputs?

  The output channels operate within a direct current voltage range of 10 to 30 VDC.

• Does the module support hot-swapping capabilities?

  Hot-swapping is not recommended while system power and field-side excitation remain energized.

• What protocol does the unit utilize for communication?

  The module communicates across proprietary industrial block I/O and remote scanner network links.

• Is the module still actively manufactured?

  No, the unit was officially discontinued by the manufacturer on June 29, 2015.

• What is the total physical weight of the hardware unit?

  The unit weighs approximately 0.78 kg excluding packaging materials.

• What tariff code applies to international shipments of this part?

  The assigned international commercial tariff code is 8538903000.