1756-L71

Technical specifications

Manufacturer

Allen-Bradley

Manufacturer part no.

1756-L71

Type

ControlLogix controller

Application

PLC controller

Used with

ControlLogix 1756 chassis

Controller tasks

32 tasks, including a combination of one continuous, periodic, and event tasks 32 programs/tasks prior to RSLogix 5000® programming software, version 15.01.00 100 programs/task beginning with RSLogix 5000 programming software, version 15.01.00 1000 programs/task beginning with Logix Designer application, version 24.00.00

Built-in communication ports

1-port USB

Communication options

EtherNet/IP, ControlNet, DeviceNet, Data Highway Plus, Remote I/O, SERCOS, Third-party process and device networks

USB port communication

Programming, configuration, firmware update, and online edits only

Controller connections supported max

500

Network connections, per network module

1000 I/O; 528 EtherNet/IP; 512 TCP (1756-EN4TR) 256 EtherNet/IP; 128 TCP (1756-EN2x) 128 EtherNet/IP; 64 TCP (1756-ENBT) 100 ControlNet (1756-CN2/A) 40 ControlNet (1756-CNB/D, 1756-CNB/E) 128 ControlNet (1756-CN2/B)

Controller redundancy

Full support

Integrated motion

SERCOS interface, Analog options (encoder input, LDT input, SSI input), Integrated Motion on the EtherNet/IP network

Programming languages

Relay ladder logic, Structured text, Function Block Diagram, Sequential function chart (SFC)

User memory

2 MB

I/O memory

0.98 MB

Nonvolatile memory storage

1 GB Secure Digital (SD) card (1784-SD1), ships pre-installed in the controller

Digital I/O max

128,000

Analog I/O max

4000

Total I/O max

128,000

Energy storage module

1756-ESMCAP, 1756-ESMCAPK capacitor energy storage module (removable, ships installed with every controller) 1756-ESMNSE, 1756-ESMNSEK capacitor energy storage module (removable, no residual WallClockTime power backup) 1756-ESMNRM, 1756-ESMNRMK capacitor energy storage module (non-removable, helps prevent USB connection and SD card use to help secure the controller)

Current draw @ 1.2V DC

5 mA

Current draw @ 5.1V DC

800 mA

Power dissipation

2.5 W

Thermal dissipation

8.5 BTU/hr

Isolation voltage

30V (continuous), basic insulation type, USB port-to-system, Compliant and tested according to IEC/UL 61010-1

USB port

USB 2.0, full speed (12 Mbps)

Weight approx

0.25 kg (0.55 lb)

Slot width

1

Module location

Chassis-based, any slot

Technical documents (1)

• Rockwell Automation technical data 1756-TD001

Key features

• 2 MB user memory and 0.98 MB I/O memory
• Supports up to 500 controller connections
• Full controller redundancy support
• Ladder logic, structured text, function block and SFC programming
• Removable capacitor energy storage module ships installed

About the Allen-Bradley 1756-L71

The Allen-Bradley 1756-L71 is a ControlLogix 2 MB controller, listed by Rockwell Automation with the lifecycle status Active Mature. Rockwell technical data 1756-TD001 gives 2 MB user memory, 0.98 MB I/O memory, a 1-port USB 2.0 full speed connection and a 1 GB SD card (1784-SD1) that ships pre-installed. The same document lists up to 500 controller connections, 128,000 total I/O, 32 tasks and full controller redundancy support. It is a one-slot chassis-based module that fits any slot, with a current draw of 800 mA at 5.1V DC and 2.5 W power dissipation.

What is the 1756-L71 used for?

The 1756-L71 runs the control program in a ControlLogix chassis and communicates with other devices through network modules such as EtherNet/IP, ControlNet and DeviceNet. Rockwell also lists integrated motion over SERCOS interface, analog options and EtherNet/IP. The USB port is for programming, configuration, firmware update and online edits only, and the module has no enclosure rating (open-style).

Lifecycle and successor

Active.

Before you order

What to photograph or confirm so the right unit is quoted.

Check that the catalog number 1756-L71 on the module label matches your part, and note the series letter and firmware revision printed there. Send us a photo of the label if you want us to confirm the details before you order.