Allen-Bradley 1756-L1M2 1MB Memory ControlLogix 5550 CPU Process Automation Controller

Brief Product Description

The Allen-Bradley 1756-L1M2 is a ControlLogix 5550 central processing unit. It provides 1 megabyte of standard internal memory for managing industrial automation applications.

Product Overview

The 1756-L1M2 operates as a foundational processor within the Allen-Bradley ControlLogix 5550 hardware family. This module executes sequential, process, drive, and motion control tasks concurrently within a single ControlLogix chassis. Consequently, industrial plants can consolidate complex control architectures using this unified platform.

The controller manages multiple communication protocols through separate network modules. It establishes deterministic data links over ControlNet, DeviceNet, and Universal Remote I/O architectures. Furthermore, this processing unit features a standard RS-232 serial communication port for local programming, runtime data collection, and operator interface connectivity. The open-style hardware architecture interfaces directly with the local ControlLogix backplane to coordinate digital, analog, and specialty I/O modules.

Key Technical Characteristics

Memory Configuration and Power Specifications

• User Memory Capacity: 1 Megabyte
• Nonvolatile Memory Storage: None
• Backplane Current Consumption at 5 Volts DC: 1.05 Amperes
• Backplane Current Consumption at 24 Volts DC: 0.02 Amperes
• Average Power Dissipation: 4.8 Watts
• Thermal Dissipation Output: 16.4 BTU per hour
• Replacement Battery Part Number: 1756-BA1 lithium assembly

Environmental and Mechanical Tolerances

• Operational Temperature Range: 0 to 60 degrees Celsius
• Storage Temperature Range: -40 to 85 degrees Celsius
• Relative Humidity Limits: 5 to 95 percent non-condensing
• Operational Vibration Resistance: 2 G peak at 10 to 500 Hertz
• Operational Shock Resistance: 30 G peak for a duration of 11 milliseconds
• Non-Operational Storage Shock: 50 G peak for a duration of 11 milliseconds

Electrical Isolation and Regulatory Compliance

• Continuous Isolation Voltage: 30 Volts
• Dielectric Test Isolation Rating: 500 Volts AC applied for 60 seconds
• Electrostatic Discharge Immunity: 6 kilovolts contact discharge
• Radiated Radio-Frequency Immunity: 10 Volts per meter from 30 to 1000 Megahertz
• Conducted Radio-Frequency Immunity: 10 Volts RMS from 150 kilohertz to 80 Megahertz
• Electromagnetic Emissions Level: Group 1, Class A industrial compliance

Industrial Applications

The 1756-L1M2 controller serves as a reliable automation hub for legacy factory environments. Manufacturing plants deploy this processor to manage mid-sized assembly operations, material handling conveyors, and water treatment processes. Moreover, the unit provides critical system continuity for facilities maintaining existing ControlLogix 5550 infrastructures without upgrading to newer ControlLogix lines. The robust environmental tolerances guarantee stable operations inside electrical enclosures facing continuous mechanical vibration and ambient temperature shifts.