Allen-Bradley 1756-L55M24 ControlLogix5555 Controller

Description

The 1756-L55M24 is a ControlLogix5555 controller manufactured by Allen-Bradley that provides central processing and control capabilities for industrial automation applications. Designed to mount directly into a ControlLogix chassis, it communicates across the backplane to manage system I/O, execute application logic, and facilitate data exchange.

Equipped with a 1756-M24 nonvolatile memory board, the 1756-L55M24 provides 3.5 MB of data and logic memory. The module features a 9-pin D-shell serial port supporting RS-232 communication for direct connection to programming workstations or external devices using a 1756-CP3 or 1747-CP3 cable. Operating status is indicated by front-panel LEDs for RUN, I/O, FORCE, RS232, BAT, and OK conditions.

Features

• Incorporates a 1756-M24 memory board delivering 3.5 MB of data and logic memory.
• Includes nonvolatile memory support for data and program retention.
• Front-panel RS-232 serial communication port for local programming and interfacing.
• Front-panel status indicators monitoring RUN, I/O, FORCE, RS232, BAT, and OK states.
• Three-position keyswitch for selecting RUN, PROG, and REM operating modes.
• Can be installed or removed under backplane power (RIUP) in non-hazardous environments.

Applications

• Factory automation systems
• Industrial process control
• Machine control and sequence management
• Distributed I/O and peer-to-peer controller communication

Technical Specifications

Connections/Interfaces

Installation Guidelines

• Handle the controller using a grounded wriststrap to prevent electrostatic discharge (ESD) damage to internal electronic components.
• Disconnect the battery from the controller before installing or replacing the memory board.
• Align the circuit board with the top and bottom chassis guides and slide the module into any slot until the locking tabs engage.
• Install and connect a 1756-BA1 lithium battery module before applying system power.
• Ensure that power is removed or the location is verified as non-hazardous prior to connecting/disconnecting the serial cable, battery, or backplane connection.
• Mount the ControlLogix chassis inside a suitable enclosure meeting system environmental requirements.

Compliance and Certifications

• UL Listed Industrial Control Equipment (File E65584)
• CSA Certified Process Control Equipment (File LR54689C)
• CSA Certified Process Control Equipment for Class I, Division 2 Group A, B, C, D Hazardous Locations (File LR69960C)
• CE Compliant (EMC Directive 2004/108/IEC: EN 61326-1, EN 61000-6-2, EN 61000-6-4, EN 61131-2)
• C-Tick Compliant (AS/NZS CISPR 11)
• EEx / ATEX Certified (Directive 94/9/EC, EN 60079-15 Zone 2)