Allen-Bradley 1756-CMS1C1 ControlLogix Compute Module

Configured for embedded computing, diagnostics, and event sequencing in ControlLogix systems, the Allen-Bradley 1756-CMS1C1 (1756-CMS1C1 ControlLogix Compute Module) provides direct physical/electrical execution through a Linux-based processing environment integrated into the ControlLogix chassis backplane. It combines dual-core processing and solid-state storage for runtime computation, SOE handling, and controller-adjacent diagnostics.

Hardware Specifications

ControlLogix Compute Integration Characteristics

The 1756-CMS1C1 compute module operates through ControlLogix backplane communication infrastructure, where deterministic data exchange is synchronized with controller task execution. Backplane bus communication velocity is governed by chassis architecture and module configuration, enabling compute-to-controller coordination for time-stamped event processing.

EtherNet/IP deterministic networks are indirectly supported through controller-side routing, while the compute module executes local processing tasks including diagnostics aggregation and sequence-of-events generation. Firmware flash compatibility is managed via Studio 5000 integration layer, ensuring version alignment between compute runtime and ControlLogix controller firmware.

I/O density scaling is not applicable at signal termination level but impacts system-level architecture through compute-assisted diagnostics and event processing loads distributed across the chassis.

Frequently Asked Questions (FAQ)

Q: Does the 1756-CMS1C1 support RIUP (Removal and Insertion Under Power)?
A: Yes. The module supports RIUP operation when installed in a compatible ControlLogix chassis, subject to system configuration and backplane state conditions.

Q: How does the module affect ControlLogix backplane loading?
A: It introduces additional backplane communication and power draw dependent on runtime processing load, while remaining within chassis-defined current limits.

Q: Is firmware upgrade independent from ControlLogix controller firmware?
A: No. Firmware compatibility is tied to Studio 5000 and system firmware alignment between the compute module and host controller environment.

Field Installation Guidelines

The module shall be installed only in an energized or de-energized ControlLogix chassis according to maintenance procedure. Ensure chassis power budget verification prior to insertion. Insert module into designated slot until backplane connector is fully engaged.

Maintain proper grounding of the ControlLogix chassis to prevent backplane communication noise. Avoid routing high-voltage field wiring parallel to backplane or communication cabling.

Do not apply mechanical stress to the module during insertion or removal. Verify Studio 5000 configuration before system restart to ensure correct module recognition.