1756-L71 ControlLogix 5571 2MB Controller | Allen-Bradley

The Original New Allen-Bradley 1756-L71 ControlLogix 5571 Controller is a high-performance programmable automation controller (PAC) designed for advanced industrial automation and control applications. Part of the ControlLogix 5570 family, it delivers 2 MB of user memory and 0.98 MB of I/O memory, providing robust processing power for complex control logic, data acquisition, and integrated motion control. The controller features an onboard 4-character alphanumeric display for real-time monitoring of run-time information and diagnostic status, a USB programming port, and full redundancy support, making it ideal for mission-critical applications in discrete manufacturing, process control, and large-scale automation systems.

Core Engineering Highlights:
2 MB user memory | 0.98 MB I/O memory | 1 GB non-volatile SD card (1784-SD1) | 32 tasks / 100 programs per task | 500 controller connections | 1 USB port | Full redundancy support | Integrated motion control (SERCOS, EtherNet/IP, analog encoder, SSI, LDT) | 0°C to 60°C operating | Open enclosure | 2.5W power dissipation

Key Features:

• Original New Allen-Bradley 1756-L71 controller

• 2 MB user memory and 0.98 MB I/O memory

• 1 GB non-volatile memory via Secure Digital (SD) card (1784-SD1 included, upgradeable to 2 GB with 1784-SD2)

• Onboard 4-character alphanumeric display for run-time and diagnostic monitoring

• USB programming port (Type B, full-speed)

• Supports up to 32 tasks with 100 programs per task

• Up to 500 controller connections

• Supports 128,000 digital I/O points and 4,000 analog I/O points

• Full controller redundancy support

• Integrated motion control: SERCOS interface, analog encoder input, LDT input, SSI input, motion on EtherNet/IP

• Optional communication adapters: EtherNet/IP, ControlNet, DeviceNet, DH+, Remote I/O, SynchLink

• Chassis mounting (ControlLogix 1756 chassis)

• Open-style enclosure

• Active Mature Product lifecycle

Applications:

• Discrete manufacturing automation (conveyors, robotics, packaging machinery)

• Process control (heating, cooling, pumping, batch processing)

• High-speed data acquisition and processing

• Integrated motion control systems

• Redundant control systems for mission-critical applications

• Automotive assembly lines

• Pharmaceutical batch processing

• Water treatment and power generation facilities

Technical Specifications:

• Catalog Number: 1756-L71

• Product Family: ControlLogix 5570

• Product Type: Programmable Automation Controller (PAC)

• User Memory: 2 MB

• I/O Memory: 0.98 MB

• Non-Volatile Memory: 1 GB SD card (1784-SD1)

• Digital I/O (Max): 128,000 points

• Analog I/O (Max): 4,000 points

• Tasks: 32

• Programs per Task: 100

• Controller Connections: 500 max

• Communication Ports: 1 USB (Type B, full-speed)

• Optional Communication Adapters: EtherNet/IP, ControlNet, DeviceNet, DH+, Remote I/O, SynchLink

• Integrated Motion: SERCOS interface, analog encoder input, LDT input, SSI input, motion on EtherNet/IP

• Display: 4-character alphanumeric

• Redundancy: Full support

• Backplane Current: 5 mA @ 1.2V DC; 800 mA @ 5.1V DC

• Power Dissipation: 2.5 W

• Thermal Dissipation: 8.5 BTU/hr

• Isolation Voltage: 30V continuous

• Replacement Battery: 1756-ESMCAP

• Mounting: ControlLogix chassis (1756-A series)

• Enclosure Type: Open

• Dimensions (HxWxD): 5.512 cm (height)

• Weight: 1.00 lb (0.45 kg)

• Operating Temperature: 0°C to 60°C (32°F to 140°F)

• Storage Temperature: –40°C to 85°C

• Operating Humidity: 5% to 95% non-condensing

• Vibration: 2g @ 10 to 500 Hz

• Certifications: CE, ATEX, IECEx, UL Listed, cULus, KC, RCM, ABS, RINA

System Compatibility:

• Rockwell Automation ControlLogix 5570 controllers

• GuardLogix 5570 safety controllers

• 1756 ControlLogix chassis (1756-A4, 1756-A7, 1756-A10, 1756-A13, 1756-A17, and K-series variants)

• 1756 series power supplies

• 1756 series communication modules (EtherNet/IP, ControlNet, DeviceNet)

• 1756 series I/O modules (digital, analog, diagnostic, motion, specialty)

• 1756-RM2 redundancy module

• 1784-SD1 / 1784-SD2 Secure Digital memory cards

• Studio 5000 Logix Designer® application

• RSLogix 5000 software

Typical System Architecture:
1756 Power Supply (e.g., 1756-PA72 / 1756-PB72)
↓
1756-A10 / 1756-A13 ControlLogix Chassis
↓
1756-L71 ControlLogix 5571 Controller
↓
1756-EN2T / 1756-EN3TR EtherNet/IP Communication Module
↓
1756 Digital / Analog I/O Modules
↓
EtherNet/IP Network (DLR / Star / Linear)
↓
Up to 500 Controller Connections

Related Products:

• 1756-L72 – 4 MB ControlLogix 5571 controller (higher memory)

• 1756-L73 – 8 MB ControlLogix 5571 controller

• 1756-L74 – 16 MB ControlLogix 5571 controller

• 1756-EN2T – EtherNet/IP communication module

• 1756-EN3TR – Dual-port EtherNet/IP module with DLR

• 1756-RM2 – Redundancy module

• 1784-SD2 – 2 GB Secure Digital memory card

• 1756-ESMCAP – Energy storage capacitor module (replacement battery)

• 1756-IB16 – 16-point 24V DC digital input module

• 1756-OB16E – 16-point electronic fusing digital output module

• 1756-IF8 – 8-channel analog input module

• 1756-A10 – 10-slot ControlLogix chassis

• 1756-PA72 – ControlLogix power supply, 120/240V AC, 10A

PLC ERA is an independent industrial automation distributor supplying 100% genuine Original New products through established global supply channels. Allen-Bradley, ControlLogix, GuardLogix, and Studio 5000 are trademarks of Rockwell Automation.