Boolean Control Module 1769-BOOLEAN Allen-Bradley

Product Overview

The 1769-BOOLEAN is a specialized high-speed combination I/O module designed for the CompactLogix platform. Unlike standard I/O modules, it integrates an on-board logic processor capable of executing Boolean expressions (AND, OR, XOR, or NONE) with an ultra-fast closed-loop response time of 1 microsecond. This architecture makes the 1769-BOOLEAN ideal for time-critical applications where the main controller scan time is insufficient to react to fast-changing field signals.

Technical Specifications

Logic and Control Architecture

The 1769-BOOLEAN evaluates real-time physical inputs as well as virtual inputs received from the backplane. When a configured Boolean expression evaluates to TRUE, the associated output transitions to the ON state immediately, bypassing the standard Requested Packet Interval (RPI) processing of the controller. This hardware-level execution ensures deterministic performance suitable for safety interlocks, high-speed sorting, pulse detection, and similar ultra-fast control tasks.

Comparison of Boolean Operations

• AND: Output is energized only when all specified input conditions are TRUE.

• OR: Output is energized when any one of the specified input conditions is TRUE.

• XOR: Output is energized only when an odd number of inputs are TRUE (exclusive OR).

• NONE: Output is controlled directly by the user program, operating as standard discrete I/O.

Common Technical Questions

Can this module be used without a CompactLogix CPU?
No. Although the 1769-BOOLEAN performs logic processing internally, it must be installed in a CompactLogix local rack or a distributed I/O system (such as a 1769-AENTR) to receive configuration data and operating power from the backplane.

What is the advantage of sourcing outputs on this module?
Sourcing outputs supply the positive voltage (+) to the load. This wiring convention is widely used in North American industrial systems and improves safety, as an accidental short to ground will not energize the load.