The Allen-Bradley 1756-L74 is a ControlLogix programmable automation controller designed for demanding industrial automation and process control applications. Installed in a ControlLogix chassis, the 1756-L74 manages system I/O modules across the backplane and over network links to provide real-time control, high-speed data processing, and integrated motion capabilities. Featuring 16 MB of user memory and 0.98 MB of dedicated I/O memory, the module offers flexible programming options and communication interfaces for factory automation, process systems, and heavy industrial machinery.
Features
16 MB user memory and 0.98 MB I/O memory
Integrated 1-port USB local programming interface
Support for non-volatile storage via Secure Digital (SD) card
Uses 1756-ESMCAP energy storage capacitor module
Low power consumption at 5 mA @ 1.2V DC and 800 mA @ 5.1V DC
Applications
Factory automation and assembly lines
Industrial process control systems
Motion and drive control architectures
Distributed I/O systems and plant-wide control networks
Technical Specifications
Parameter
Value
Manufacturer
Allen-Bradley / Rockwell Automation
Catalog Number
1756-L74
UPC
612598876044
User Memory
16 MB
I/O Memory
0.98 MB
Local Programming Port
1 USB
Embedded Network Port
False
Non-Volatile Memory Option
Secure Digital
Replacement Energy Storage
1756-ESMCAP
Current Draw @ 1.2V DC
5 mA
Current Draw @ 5.1V DC
800 mA
Installation Guidelines
Chassis Mounting: Ensure the controller is fully seated into any available slot of a compatible ControlLogix chassis before applying power.
Energy Storage Module: Install the required 1756-ESMCAP energy storage capacitor module to maintain memory backup functionality without traditional batteries.
Local USB Port Connection: The front panel USB port is provided for temporary local programming, configuration, and firmware updates only.
Grounding & Power: Verify that the chassis and power supply are properly grounded according to standard industrial wiring and grounding guidelines to mitigate EMI/RFI noise.
FAQ
What is the memory capacity of the module?
The device features 16 MB of user memory and 0.98 MB of I/O memory.
What local programming port is available on the controller?
The device includes 1 USB port designed for temporary local programming and configuration.
What energy storage option is used as a replacement battery?
The controller uses the 1756-ESMCAP capacitor module for energy storage.
Does the device have an embedded network port?
No, the device does not feature an embedded network port.
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