Configured for high-speed logic execution and centralized motion processing in ControlLogix industrial controller chassis, the Allen-Bradley 1756-L71K (1756-L71 Processor Module) provides direct physical/electrical execution. It manages sequence control, user memory structures, and task scheduling across local and distributed I/O networks.

Catalog Designation & Part Nomenclature

• 1756: ControlLogix chassis-based programmable automation controller hardware platform.
• L71: ControlLogix 5570 controller series with 2 MB user memory capacity.
• K: Conformal coating option for protection against harsh chemical and atmospheric environments.

Technical Specifications & Operating Parameters

Deterministic Architecture & Network Communication Integration

The controller interfaces directly with the chassis backplane bus communication velocity framework, establishing real-time synchronization with local and remote I/O chassis. Fully integrated into EtherNet/IP deterministic networks, the module handles high-density I/O density scaling up to 128,000 total digital signals. Firmware flash compatibility enables seamless field upgrades and consistent project synchronization through Studio 5000 Logix Designer environments.

Package Fulfillment Details

• 1 x Allen-Bradley 1756-L71K controller module in anti-static packaging
• 1 x Key switch assembly for controller mode selection
• 1 x Printed installation instruction manual

Mechanical Insertion & Wiring Standards

• Align the module card edges with the top and bottom chassis slot guides before sliding firmly until both locking tabs click.
• Verify proper chassis frame grounding to a dedicated earth ground bus bar prior to applying control power.
• Maintain minimum panel clearances of 50 mm above and below the chassis assembly to preserve convective thermal airflow.
• Connect USB configuration cables only to designated front-panel diagnostic ports during maintenance procedures.

Technical Hardware Reference FAQ

• What is the total user memory capacity available for user program storage?

  The module provides 2 MB of dedicated user memory along with an additional 0.98 MB designated for I/O data structures.

• Does this processor support removal and insertion under power (RIUP)?

  Yes, the module can be safely inserted or removed from the backplane chassis while system power is actively applied.

• What amount of backplane current does the unit draw at 5.1 VDC?

  The module draws a maximum of 800 mA from the 5.1 VDC backplane bus rail during standard operating conditions.

• What is the continuous isolation voltage rating for the controller?

  The hardware features a continuous isolation voltage rating of 30 V tested between internal circuitry and backplane.

• How many total digital I/O points can this processor control?

  The processor architecture supports up to 128,000 total digital I/O points across backplane and networked sub-nets.

• What functional protection does the "K" catalog suffix denote?

  The "K" suffix indicates a factory-applied conformal coating designed to protect internal circuits from environmental contaminants.

• What is the maximum power dissipation rating of the module?

  Under full operational load, the module dissipates up to 2.5 W of electrical power within the chassis frame.

• Is external battery power required to maintain user memory during power loss?

  No, 1756-L70 series processors utilize energy storage modules (ESM) to eliminate traditional lithium battery maintenance.