1756-L1 Allen-Bradley ControlLogix Logix5550 CPU Module

Overview

The Allen-Bradley 1756-L1 belongs to the ControlLogix Logix5550 family of programmable automation controllers (PACs). Designed for high-performance control, it offers robust communication capabilities and modular expandability suitable for industrial automation systems. With 64 KB of user memory, it provides efficient processing for discrete, analog, and motion control tasks in demanding applications.

Technical Specifications

• Manufacturer: Allen-Bradley

• Product Line: ControlLogix Logix5550 Series

• Model / Part Number: 1756-L1

• Product Type: Processor Module / Controller

• User Memory: 64 KB

• Communication Port: One (1) RS-232 serial port

• Compatible Memory Modules: 1756-M1, 1756-M2, 1756-M3

• Compatible Battery Backups: 1756-BA1, 1756-BA2

• Communication Cable: 1756-CP3

• Backplane Current Draw:

• 5V DC: 120 mA

• 24V DC: 2 mA

• Power Dissipation (Max): 4.1 W at 60°C

• Isolation Voltage: 30V DC continuous

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

• Storage Temperature: -40 to 85°C (-40 to 185°F)

• Enclosure Type: Open-style module

• Slot Width: Single-slot (1)

• Mounting Type: Chassis-based

• Minimum Operating Current: 2 mA @ 10V DC

• Maximum Operating Current: 3.5 mA @ 30V DC

• Maximum Input Current (Off-State): 1.5 mA

• Weight: 0.63 lbs (0.28 kg)

• Removable Terminal Blocks: 1756-TBCH, 1756-TBS6H

Key Features

• 64 KB onboard memory for control and logic processing

• RS-232 communication for HMI or programming interface

• Supports modular expansion with ControlLogix I/O chassis

• Battery backup for memory retention and system reliability

• Open-style chassis mounting for flexible configuration

• Wide temperature range suitable for industrial environments

• Low power consumption with efficient backplane communication

Application Scenarios

• Factory automation and process control

• Material handling and packaging systems

• Batch control and motion coordination

• OEM equipment requiring compact logic processing

• ControlLogix-based distributed automation systems

FAQs

Q: What memory modules are compatible with the 1756-L1 controller?
A: The 1756-L1 supports memory expansion using modules 1756-M1, 1756-M2, or 1756-M3.

Q: Which power supplies can be used with this module?
A: It is compatible with standard ControlLogix power supplies such as the 1756-PA and 1756-PB series.

Q: Does the 1756-L1 support redundancy?
A: No, the 1756-L1 does not include redundancy capability. For redundant systems, Allen-Bradley offers the 1756-RM redundancy module.

Q: What communication cable should be used for RS-232 programming?
A: Use 1756-CP3 cable for reliable serial communication between the module and programming terminal.