1756-L71S

Technical specifications

Manufacturer

Allen-Bradley

Manufacturer part no.

1756-L71S

Type

GuardLogix safety controller

Application

PLC controller

Used with

ControlLogix 1756 chassis

Safety communication options

Standard and safety, EtherNet/IP, ControlNet, DeviceNet

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) 128 ControlNet (1756-CN2/B) 100 ControlNet (1756-CN2/A) 40 ControlNet (1756-CNB/D, 1756-CNB/E)

Programming languages

For the safety task, GuardLogix controllers support Ladder Diagram only., For standard tasks, GuardLogix controllers support: – Ladder Diagram (LD) – Structured Text (ST) – Function Block Diagram (FBD) – Sequential Function Chart (SFC)

User memory

2 MB

Safety memory

1 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 modules

1756-ESMCAP capacitor energy storage module (removable, ships installed with every controller) 1756-ESMNSE capacitor energy storage module (removable, no residual, WallClockTime power backup) 1756-ESMNRM 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, USB port-to-system, Compliant and tested according to IEC/UL 61010-1

Weight, approx

0.25 kg (0.55 lb)

Slot width

2 (both modules needed; each is one slot)

Module location

Chassis-based, any slot

Chassis

1756-A4, 1756-A4K, 1756-A7, 1756-A7K, 1756-A10, 1756-A10K, 1756-A13, 1756-A13K, 1756-A17, 1756-A17K

Power supply, standard

1756-PA50, 1756-PA50K, 1756-PA72, 1756-PA72K, 1756-PA75, 1756-PA75K, 1756-PB50, 1756-PB50K 1756-PB72, 1756-PB72K, 1756-PB75, 1756-PB75K, 1756-PC75, 1756-PH75

Power supply, redundant

1756-PA75R, 1756-PA75RK, 1756-PB75R, 1756-PB75RK, 1756-PSCA2, 1756-PSCA2K

Wire category

3 - on USB ports

Temperature code

T4

Enclosure type rating

None (open-style)

Technical documents (1)

• Rockwell Automation technical data 1756-TD001

Key features

• 2 MB user memory and 1 MB safety memory
• Supports up to 128,000 total I/O
• 1 GB SD card ships pre-installed
• Safety task programmed in Ladder Diagram only
• Standard and safety options on EtherNet/IP, ControlNet, DeviceNet

About the Allen-Bradley 1756-L71S

The Allen-Bradley 1756-L71S is the Logix 5571S Automation Controller 2/1M, a chassis-based controller that Rockwell Automation lists with an Active Mature lifecycle status. According to Rockwell technical data 1756-TD001, it has 2 MB of user memory, 1 MB of safety memory and 0.98 MB of I/O memory, with a maximum of 128,000 total I/O. It draws 800 mA at 5.1 V DC, dissipates 2.5 W and weighs approximately 0.25 kg. Rockwell states a slot width of 2, with both modules needed and each taking one slot.

What is the 1756-L71S used for?

The 1756-L71S runs the control program in a 1756 chassis and can be fitted in any slot. Rockwell lists standard and safety communication options over EtherNet/IP, ControlNet and DeviceNet. Standard tasks can use Ladder Diagram, Structured Text, Function Block Diagram and Sequential Function Chart, while the safety task supports Ladder Diagram only.

Lifecycle and successor

Active.

Before you order

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

Check that the catalog number on the module label reads 1756-L71S, and note the series letter and firmware revision printed on the label. Send us a photo of the label if you want us to confirm the part before ordering.