1756-L65 Allen-Bradley ControlLogix 32MB User Memory CPU Unit

Core Functionality and Architecture

The 1756-L65 stands as a flagship member of the ControlLogix 5565 family, engineered to execute high-intensity logic and motion control within a single chassis. By leveraging a multi-tasking operating system, the processor allows engineers to prioritize critical control paths and maintain consistent scan times. It features an integrated RS-232 serial port for local programming and peripheral connectivity. Furthermore, the 32 MB of on-board volatile memory provides ample space for sophisticated program code and extensive tag databases. To ensure data persistence during power loss, the module utilizes a 1756-BA2 lithium battery and supports nonvolatile storage through the 1756-CF128 CompactFlash card.

Technical Performance and I/O Capacity

This processor manages vast I/O configurations, supporting up to 128,000 total digital points and 4,000 analog points. Such capacity makes it ideal for expansive manufacturing plants and utility infrastructure. The module draws 1200 mA at 5.1V DC and operates with a power dissipation of 3.5 Watts. For environmental protection, the hardware features a continuous isolation voltage rating of 30V and has undergone rigorous type-testing at 720V DC. These safeguards prevent electrical interference from compromising the logic execution in high-voltage industrial zones.

Connectivity and Network Integration

Integration into modern factory networks remains seamless due to the 1756-L65’s broad protocol compatibility. It supports up to 250 concurrent controller connections, enabling massive data exchange across the enterprise. Supported communication layers include:

• EtherNet/IP and ControlNet for real-time control
• DeviceNet for device-level networking
• Remote I/O and DH+ for legacy system migration
• DF1, ASCII, and Modbus via specialized logic routines

Environmental Resilience and Installation

The mechanical design of the 1756-L65 focuses on longevity in harsh settings. It sustains optimal performance within an operating temperature range of 0 to 60°C. Additionally, the unit resists significant physical stress, featuring a vibration tolerance of 2 g and functional shock resistance up to 50 g. The hardware fits into any standard ControlLogix chassis, including the A4, A7, A10, A13, and A17 series, providing flexibility for system designers.

Technical Specifications Summary

• Manufacturer: Allen-Bradley / Rockwell Automation
• Model Series: ControlLogix 5565
• User Memory: 32 MB Volatile
• I/O Memory: 478 KB
• Current Draw: 1.2A @ 5.1V DC
• Thermal Dissipation: 11.9 BTU/hr
• Dimensions: 3.5 x 14 x 14.5 cm
• Weight: 0.4 kg