Allen Bradley 1756-L81E ControlLogix Processor

The AB 1756-L81E is a high-speed ControlLogix 5580 programmable automation controller (PAC) offering 3 MB of user memory and optimized for large, data-intensive control tasks. With a built-in 1 Gb Ethernet port, integrated USB, and support for up to 60 EtherNet/IP devices, the L81E delivers exceptional performance, connectivity, and scalability for advanced industrial automation systems.

This modular controller is suitable for high-availability and safety-related applications, certified to SIL 2 and PL d. Designed for use with Studio 5000 and embedded with a 4-character alphanumeric display, the 1756-L81E enables intuitive diagnostics and smooth integration within ControlLogix chassis.

Technical Specifications

Model: 1756L81E
Series: ControlLogix 5580
Type: Programmable Automation Controller (PAC)
User Memory: 3 MB (3072 KB)
Controller Type: Modular
Display: 4-character alphanumeric LED
Mounting: ControlLogix chassis (rack assembly only)
Front Installation: Supported
Battery Backup: Optional Energy Storage Module (1756-ESMC series)

Electrical Specifications

Input Voltage: Supplied via ControlLogix chassis backplane
Backplane Current Draw:
• 5.1V DC @ 1.2 A
• 24V DC @ 14 mA
Power Dissipation: Approx. 5.8 W
Heat Dissipation: Approx. 19.8 BTU/hr
Isolation Voltage: 30V (continuous), basic insulation
Protection Type: Surge and overcurrent protection via chassis

Network & Interface Specifications

Integrated Interfaces:

• Ethernet Port: 1 x 1 Gb (embedded EtherNet/IP)
• USB Port: 1 x USB Type B (for programming and diagnostics)

Supported Protocols:
EtherNet/IP
Modbus TCP/IP (via application logic)
CIP Motion
CIP Safety
(Does not support SERCOS or legacy protocols directly)

Max EtherNet/IP Devices: 60
Max I/O Connections: 500
Software Environment: Studio 5000 Logix Designer (v28 or later)
Network Redundancy: Supported with appropriate configuration

Mechanical Specifications

Width: 34.55 mm
Height: 145.2 mm
Depth: 136.6 mm
Mounting Orientation: Vertical (rack only)
Rack Assembly: Yes
Rail Mounting: Not supported
Weight: Approx. 0.4 kg
Enclosure Type: Open-type for control cabinet installation

Environmental Specifications

Operating Temperature: 0…60 °C
Storage Temperature: –40…85 °C
Relative Humidity: 5% to 95% non-condensing
Shock Rating: 30 g operating, 50 g non-operating
Vibration Resistance: 2 g @ 10–500 Hz
Pollution Degree: 2
Certifications: Class I Div 2 Groups A, B, C, D

Compliance & Certifications

Certifications: UL, c-UL, CE, ATEX, RoHS
SIL Rating: SIL 2 (IEC 61508)
Performance Level: PL d (EN ISO 13849-1)
EMC Compliance: EN 61000-6-2 / 6-4
Standards Met: EN 61131-2
Functional Safety: Suitable for safety-related systems with CIP Safety configuration

Key Features & Benefits

✅ 3 MB User Memory – Handles large, complex control logic with ease

✅ Integrated 1 Gb EtherNet/IP Port – High-speed network performance for fast data throughput

✅ SIL 2 / PL d Certified – Trusted for safety-critical automation environments

✅ Compact Modular Design – Installs easily into any ControlLogix chassis

✅ USB Programming Interface – Rapid firmware updates and simplified configuration

📦 Order the Allen Bradley 1756-L81E from Drive Outlet Megastore

At Drive Outlet Megastore we offer unbeatable Allen Bradley 1756-L81E prices. This powerful ControlLogix 5580 controller delivers industry-leading performance and connectivity for mission-critical automation—available now with expert technical support and rapid delivery.

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