Product Overview

The Allen-Bradley 1756-L65 is a high-capacity Logix5565™ processor within the ControlLogix® 5560 series. Engineered for complex industrial automation environments, this controller features 32 MB of volatile user memory and 478 KB of dedicated I/O memory. It serves as a powerful computational engine for large-scale applications requiring extensive data manipulation, high-speed discrete logic, and sophisticated process control.

Operating within the 1756 ControlLogix chassis platform, the 1756-L65 supports a broad spectrum of distributed I/O and communication protocols. While it includes an integrated RS-232 serial port for local programming and DF1/Modbus interfacing, its true strength lies in its ability to manage up to 250 controller connections across industrial networks like EtherNet/IP, ControlNet, and DeviceNet. For critical data persistence, the module utilizes a 1756-BA2 lithium battery and supports non-volatile storage expansion via the 1756-CF128 CompactFlash card.

Technical Performance and System Integration

The 1756-L65 is designed to handle massive I/O counts, supporting up to 128,000 total digital points and 4,000 analog points. Its multi-tasking operating system allows for the concurrent execution of multiple programs, including high-priority motion control and background diagnostic tasks. The module’s backplane current draw is rated at 1200 mA at 5.1V DC, and it is compatible with all standard 1756-A series chassis (A4 through A17).

To ensure reliability in demanding factory floor conditions, the controller is built with advanced environmental hardening. It is tested to withstand significant vibration (2 g at 500 Hz) and high-impact shocks (30 g operational). The physical architecture provides 30V continuous isolation, protecting the logic circuitry from external electrical transients and potential ground loops.

Technical Specifications

• Manufacturer: Allen-Bradley (Rockwell Automation)

• Model Number: 1756-L65

• Series: ControlLogix 5565

• User Memory: 32 MB

• I/O Memory: 478 KB

• Non-Volatile Storage: 1756-CF128 CompactFlash (Optional)

• Communication Port: RS-232 (9-pin D-shell)

• Max Digital I/O: 128,000

• Max Analog I/O: 4,000

• Backplane Current (5.1V DC): 1200 mA

• Backplane Current (24V DC): 14 mA

• Operating Temperature: 0°C to 60°C (32°F to 140°F)

• Replacement Battery: 1756-BA2 (Lithium)

• Dimensions: 3.5 x 14.0 x 14.5 cm

• Weight: 0.4 kg

Key Functional Features

• Expansive User Memory: 32MB capacity is ideal for data-intensive applications, recipe management, and extensive alarming structures.

• Protocol Versatility: Native support for DF1, DH-485, and Modbus (via logic) through the serial port, with bridging capabilities for all major 1756 network modules.

• Chassis Flexibility: Hot-swappable design allows the processor to be inserted or removed under power without disrupting other modules.

• Rugged Diagnostics: Front-panel LED indicators provide real-time status for RUN mode, Force status, Battery health, and I/O status.