The Allen-Bradley 1756-L71 is a ControlLogix 5570 Series Programmable Automation Controller (PAC) powered by a 500 MHz Logix5571 processor with 2 MB user memory. It supports up to 128,000 digital I/O and 4,000 analog I/O points, with 32 tasks, 100 programs per task, and full redundancy support. The controller handles up to 100 integrated motion axes and 500 controller connections. It features a USB 2.0 port for programming, 1 GB SD card (1784-SD1) for non-volatile memory, and a 4-character diagnostic display. Capacitor-based energy storage (1756-ESMCAP) eliminates battery dependence. Programming via Studio 5000 / RSLogix 5000 in Ladder, FBD, Structured Text, and SFC. Occupies 1 slot in ControlLogix chassis. Typical applications: large-scale process control, packaging lines, material handling, oil & gas, and water/wastewater automation.
Q: How does the 1756-L71 compare to 1756-L61?
The L71 offers 2MB memory vs 2MB on L61, but with a faster 500MHz processor, USB programming instead of RS-232, SD card storage, and capacitor-based energy storage instead of batteries.
Q: Does the L71 support redundancy?
Yes, full controller redundancy is supported with appropriate redundancy modules (1756-RM2).
Q: What programming software is required?
Studio 5000 Logix Designer or RSLogix 5000, supporting Ladder, Function Block, Structured Text, and SFC languages.
