Allen-Bradley 1769-CLL3 Compact I/O Left-to-Left Bus Expansion Cable – 3 ft (1 m) for CompactLogix 1769 Racks

Description

Technical Specifications
Product Model

1769-CLL3

Manufacturer

Rockwell Automation / Allen-Bradley

Product Type

1769 Compact I/O Left-to-Left Bus Expansion Cable

Cable Length

1.0 m (3.28 ft)

Connector Type

40-pin keyed ribbon (left-side to left-side)

Signal Carried

I/O backplane communication bus only (no power)

Backplane Power Requirement

Each I/O bank requires separate 1769 power supply module

Maximum I/O Banks per Controller

Up to 3 banks (depending on controller model), linked via CLL/CRR/CRL cables

Wire Gauge / Construction

Shielded flat ribbon, industrial-grade insulation

Operating Temperature

0 °C to +60 °C (+32 °F to +140 °F)

Storage Temperature

–40 °C to +85 °C

Relative Humidity

5% to 95% non-condensing

Agency Certifications

UL Listed, CSA Certified, CE Marked, C-Tick, FM Class I Div 2

Dimensions (Packaged)

Approx. 1000 mm L × 30 mm W × 10 mm H

Typical Application

Links two separate 1769 I/O banks left-to-left in CompactLogix systems
Main Features and Advantages
Flexible distributed I/O bank configuration:
The Allen-Bradley 1769-CLL3​ gives panel builders the freedom to split 1769-series I/O modules into multiple banks rather than mounting all modules contiguously on a single DIN rail section. This is particularly valuable in enclosures with space limitations, pre-existing wiring ducts, or where thermal management requires spacing high-dissipation modules apart. By using the Allen-Bradley 1769-CLL3, up to three I/O banks can be logically tied to one CompactLogix controller while preserving automatic I/O addressing.
Deterministic backplane communication extension:
Unlike generic patch cables, the Allen-Bradley 1769-CLL3​ is engineered to maintain signal integrity for the 1769 local I/O bus, which operates at high speed with tight timing tolerances. The shielded ribbon construction minimizes crosstalk and EMI susceptibility, ensuring that data exchange between the processor and remotely-banked modules remains deterministic and error-free even in electrically noisy industrial environments.
Keyed, foolproof connectivity:
Both ends of the Allen-Bradley 1769-CLL3​ feature polarized, keyed 40-pin connectors that mechanically prevent reverse insertion or mismating with right-side expansion ports. The connectors seat positively into the left-side bus port of any 1769 module and lock in place when the module’s bus lever is engaged, providing a secure physical and electrical connection that resists vibration loosening.
No software configuration required:
The Allen-Bradley 1769-CLL3​ is transparent to the control program. Once the expanded banks are wired with proper local power supplies and the cable is connected, the CompactLogix controller auto-detects the additional I/O points according to the I/O configuration already defined in the project file. This plug-and-play behavior reduces commissioning time and eliminates the risk of addressing errors associated with manual DIP-switch settings found on older I/O platforms.
Global compliance and durability:
Built to Rockwell Automation industrial standards, the Allen-Bradley 1769-CLL3​ meets UL, CSA, CE, and FM Class I Division 2 requirements, making it suitable for installation in oil & gas, chemical processing, and other regulated industries. Its flame-retardant jacket material and robust strain-relief at the connector interfaces ensure long service life under normal panel operating conditions.
Application Field
The Allen-Bradley 1769-CLL3​ is used wherever a CompactLogix-based control system requires more than eight 1769 I/O modules or where physical separation of I/O banks is desirable. In packaging lines, for example, machine sections may be controlled from a single CompactLogix 5370 or 5380 controller, with discrete I/O banks mounted near the infeed, fill, and discharge stations inside one large enclosure—the Allen-Bradley 1769-CLL3​ links these banks so they appear as one continuous I/O image to the CPU. Similarly, in material handling systems with distributed zone controls, the cable allows I/O modules serving different conveyor zones to be grouped logically while being spaced apart on the DIN rail to accommodate existing panel layouts or wire ducting.
System integrators also use the Allen-Bradley 1769-CLL3​ when retrofitting older PLC-5 or SLC 500 panels with CompactLogix technology; the ability to create multiple I/O banks helps reuse available panel space without rewiring all field devices to a single concentrated I/O cluster. In process skids, batching systems, and OEM machinery with modular station designs, the Allen-Bradley 1769-CLL3​ provides the flexibility to build scalable, well-organized I/O architectures that are easier to document, troubleshoot, and expand over the lifecycle of the equipment.
Related Products
1769-CLL1​ — 0.3 m (1 ft) Left-to-Left bus expansion cable for 1769 Compact I/O; used when linking closely spaced I/O banks on the same DIN rail section.
1769-CRR1​ — 0.3 m (1 ft) Right-to-Right bus extension cable; connects consecutive 1769 modules within the same I/O bank on the right-side expansion port.
1769-CRR3​ — 1.0 m (3 ft) Right-to-Right bus extension cable; allows spacing between sequentially mounted 1769 modules in the same bank.
1769-CRL1​ — 0.3 m Right-to-Left crossover cable; used to link the right port of one bank to the left port of another bank (alternative topology to CLL3).
1769-CRL3​ — 1.0 m Right-to-Left crossover cable; same function as CRL1 but with extended length for physically separated I/O banks.
1769-PA2​ — 120/240V AC power supply module for 1769 Compact I/O banks; each I/O bank connected via 1769-CLL3 requires its own 1769 power supply such as this.
1769-L24ER-QBFC1U​ — CompactLogix 5370 controller with embedded 1769 I/O and Ethernet; commonly the host processor for systems using the 1769-CLL3 to expand local I/O.
1769-ECR​ — 1769 series right-end cap / terminator; must be installed at the farthest right position of the last module in every 1769 I/O bank.