1756-L81EXT

Technical specifications

Manufacturer

Allen-Bradley

Manufacturer part no.

1756-L81EXT

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 1000 programs/task

Built-in communication ports

1-port USB, Embedded Ethernet port

USB port communication

USB 2.0, Full speed (12 Mbps), Programming, configuration, firmware update, and online edits only

Ethernet performance

10/100/1000 Mbps

I/O Capacity (Class 0/1) - packets/second

128,000 without CIP Security 40,000 with integrity 20,000 with integrity and confidentiality

Communication options

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

EtherNet/IP nodes supported max

100 nodes

Network connections per network module

ControlLogix 5580 Controllers front EtherNet/IP port. See ‘EtherNet/IP nodes supported, max’ in this table. 1000 I/O; 528 EtherNet/IP; 512 TCP (1756-EN4TR variant rated for harsh environments) 256 EtherNet/IP; 128 TCP (1756-EN2x variant rated for harsh environments) 128 EtherNet/IP; 64 TCP (1756-ENBT variant rated for harsh environments) 100 ControlNet (1756-CN2/A variant rated for harsh environments) 40 ControlNet (1756-CNB/D, 1756-CNB/E variant rated for harsh environments) 128 ControlNet (1756-CN2/B variant rated for harsh environments)

Integrated motion

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

Controller redundancy

Full support with Studio 5000 Logix Designer application version 33.00.02 or later

Programming languages

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

Standard memory

3 MB

Digital I/O, max

128,000

Analog I/O, max

4000

Nonvolatile memory storage

4 GB Secure Digital (SD) card (1784-SD4XT), ships pre-installed in the controller

Energy storage module

Embedded in controller, non-removable

Number of power cycles

80,000

Current draw @ 1.2V DC

5.0 mA

Current draw @ 5.1V DC

1.20 A

Power dissipation

6.2 W

Thermal dissipation

21.2 BTU/hr

Isolation voltage

50V (continuous), Basic Insulation type, USB port to backplane, Ethernet port to backplane, and USB port to Ethernet port, Compliant and tested according to IEC/UL 61010-1

Weight, approx

0.394 kg (.868 lb)

Slot width

1

Module location

Chassis-based, any slot

Technical documents (1)

• Rockwell Automation technical data 1756-TD001

Key features

• Conformally coated for extreme environment use
• Embedded Ethernet port and 1-port USB 2.0
• Supports 32 tasks with 1000 programs per task
• Programmable in ladder, structured text, FBD and SFC
• Chassis-based, one slot wide, any slot location

About the Allen-Bradley 1756-L81EXT

The Allen-Bradley 1756-L81EXT is a ControlLogix 5580 XT Controller, described by Rockwell Automation as an eXTreme Environment Controller with 3 MB user memory, 100 EtherNet/IP devices and conformal coating. Rockwell lists its lifecycle status as Active. Rockwell's technical data gives an operating temperature of -25 °C ≤ Ta ≤ +70 °C and a 4 GB Secure Digital card (1784-SD4XT) pre-installed in the controller. It is a chassis-based module, one slot wide, for use in the 1756-A7XT, 1756-A10XT, Series C 1756-A7ZXT or 1756-A10ZXT chassis.

What is the 1756-L81EXT used for?

The 1756-L81EXT runs the control program in a ControlLogix chassis and communicates over networks including EtherNet/IP, ControlNet, DeviceNet, Data Highway Plus, Remote I/O and SERCOS. Rockwell lists integrated motion on the EtherNet/IP network and via SERCOS interface, and full controller redundancy support with Studio 5000 Logix Designer version 33.00.02 or later. It supports up to 128,000 digital I/O and 4000 analog I/O.

Lifecycle and successor

Active.

Before you order

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

Check that the catalog number 1756-L81EXT, the series letter and the firmware revision on the label match your requirement. Send us a photo of the label if you want us to confirm the part before ordering.