Allen-Bradley 1756-L71S GuardLogix 5570 PLC Controller

Overview

The Allen-Bradley 1756-L71S is a high-performance GuardLogix 5570 controller designed for advanced industrial automation. It combines standard ControlLogix features with integrated safety capabilities, enabling reliable SIL 3 or Cat. 4/PLe operations.

Memory and Processing

This controller provides 2 MB of user memory and 1 MB of safety memory. It includes 0.98 MB I/O memory and ships with a 1 GB pre-installed Secure Digital card, expandable to 2 GB. The 1756-L71S can manage up to 128,000 digital I/O and 4000 analog I/O points. It supports 31 standard tasks and one safety task with up to 100 programs per task.

Communication and Integration

The controller includes a built-in USB port and supports optional EtherNet/IP, ControlNet, and DeviceNet adapters. It allows seamless I/O monitoring over backplane and I/O links, ensuring fast, reliable communication with networked devices.

Electrical and Thermal Specifications

The 1756-L71S draws 5 mA at 1.2V DC and 800 mA at 5.1V DC. Its power dissipation is 2.5 W with thermal dissipation rated at 8.5 BTU/hr. The controller offers 30V continuous isolation for safe operation in open-style enclosures.

Safety Features

Paired with the 1756-L7SP safety module, the 1756-L71S provides dual-processor operation to meet rigorous safety standards. It automatically configures the safety partner, simplifying project setup while maintaining high-speed logic and motion control.

Physical and Environmental

The controller weighs 0.55 lbs and can be installed in any slot within a ControlLogix 1756 chassis. It functions efficiently across industrial operating environments, ensuring stable performance in diverse conditions.

Energy Storage and Optional Expansion

The 1756-L71S operates with the 1756-ESMCAP and 1756-ESMCAPK Energy Storage Modules, eliminating the need for lithium batteries. Optional non-volatile storage can be expanded using 1784-SD1 or 1784-SD2 cards, enabling flexible memory management.