The Allen-Bradley 1756-L73XT, also cataloged as the 1756-L73XT Processor Module, operates as a dedicated hardware component for executing controller logic, memory management, and I/O data processing within ControlLogix automation platforms.

Model Reference and Configuration

The Allen-Bradley 1756-L73XT is a ControlLogix processor module designed for Logix controller applications requiring program execution, communication handling, and distributed I/O management. The module provides controller memory resources and processes digital and analog I/O data through the ControlLogix backplane.

The XT designation identifies a processor variant within the ControlLogix family. Configuration requires compatible chassis installation, controller firmware, and Logix programming software support.

Hardware Specifications

ControlLogix Processor Architecture

The 1756-L73XT uses the ControlLogix processor architecture for application program execution and system coordination. The processor manages controller tasks, data tags, communication services, and I/O updates through the chassis backplane.

ControlLogix systems use deterministic backplane communication to exchange data between processors, communication modules, and I/O modules. Proper firmware flash compatibility and controller configuration are required before integration into an operating system.

Backplane Communication and Firmware Compatibility

The processor communicates with installed ControlLogix modules through the chassis backplane. Module recognition depends on controller firmware revision, electronic keying configuration, and Logix project settings.

Firmware flash compatibility must be verified before replacement or system expansion. Incorrect firmware combinations may prevent controller startup or module synchronization.

Ordering Information

• 1 x Allen-Bradley 1756-L73XT ControlLogix Processor Module
• 1 x Processor module housing assembly
• 1 x Product identification label
• ControlLogix chassis, power supply, communication modules, and programming software are not included unless separately specified

Installation Guidelines

Chassis Installation

• Install the processor module into a compatible ControlLogix chassis slot.
• Confirm chassis power capacity before connecting additional modules.
• Verify module locking tabs are fully engaged after insertion.

Electrical and Configuration Checks

• Confirm backplane power availability before startup.
• Use proper grounding practices for the ControlLogix chassis.
• Verify firmware revision compatibility between processor and project file.
• Check controller diagnostics after power application.

Industrial Control Platform Features

The 1756-L73XT supports industrial control applications requiring processor-based execution and distributed I/O coordination. The ControlLogix platform provides scalable I/O density through chassis-based module expansion.

For EtherNet/IP or other communication networks, network modules must be configured separately. The processor manages application execution while communication interfaces are handled by compatible ControlLogix communication modules.

Frequently Asked Questions

• What is the primary function of the 1756-L73XT?

  The module executes Logix controller programs, manages controller memory, and processes I/O data within a ControlLogix chassis.

• How much user memory is available?

  The processor provides 8 MB of user memory for controller applications, data tags, and program execution requirements.

• What I/O capacity does the processor support?

  The processor supports up to 128,000 digital I/O points and up to 4,000 analog I/O points.

• What is the power consumption of the module?

  The processor has a power dissipation rating of 2.5 W with thermal dissipation of 8.5 BTU per hour.

• What backplane current is required?

  The module requires 800 mA at 5.1 VDC and 5 mA at 1.2 VDC based on provided specifications.

• Is firmware compatibility required before installation?

  Yes. Processor firmware, controller software version, and project configuration must be compatible before operation.

• Can the processor communicate directly with field devices?

  The processor manages control logic and data processing. Field communication requires compatible communication modules.

• Does the module support ControlLogix chassis expansion?

  Yes. The processor operates within ControlLogix chassis systems where additional I/O and communication modules can be installed.