PRODUCT INFORMATION
Product Overview
The Allen-Bradley 1756-L71S is a ControlLogix Controller designed for safety and standard industrial operations. It operates as part of the Logix5000 family of automation controllers. The unit features 2 MB of user memory, 1 MB of safety memory, and 0.98 MB of dedicated I/O memory. It requires a companion 1756-L7SP safety module to achieve SIL 3 or Category 4 PLe safety standards.
This controller supports up to 128,000 digital I/O points and 4,000 analog I/O points across industrial systems. It mounts directly into any available chassis slot within a standard 1756 ControlLogix chassis. Integrated energy storage modules eliminate the need for lithium batteries during normal operation. A built-in USB port provides local programming, online editing, and diagnostics.
TECHNICAL DATA
Technical Specifications
| Parameter | Specification |
|---|
| UPC | 885630016467 |
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| Weight | 1.13 lbs (0.51 kg) |
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| User Memory | 2 MB |
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| Module Type | Processor Module |
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| Safety Memory | 1 MB |
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| Non-volatile memory | 1GB (ships with the controller) |
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| Maximum I/O | 128000 |
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| Maximum Analog I/O | 4000 |
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| No. of standard task | 31 |
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| No. of safety task | 1 |
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| Programs per task | 100 programs |
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| Event Tasks | All triggers |
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| Built-in communication | 1 USB port |
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| Optional Communication adapters | • EtherNet/IP • ControlNet • DeviceNet |
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| Redundancy | Not supported |
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| I-O Memory | 0.98 MB |
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| Maximum Digital I-O | 128,000 |
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| Current Draw (1.2 Volts DC) | 5 Miliamperes |
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| Current Draw (5.1 Volts DC) | 800 Miliamperes |
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| Power Dissipation | 2.5 Watts |
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| Thermal Dissipation | 8.5 BTU per hour |
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| Isolation Voltage | 30 Volts Continuous |
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| Enclosure | None (Open-Style) |
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TECHNICAL INFORMATION
Features
- Provides 2 MB user memory and 1 MB dedicated safety memory.
- Allocates 0.98 MB memory specifically for input and output operations.
- Achieves SIL 3 and Cat. 4/PLe standards with a 1756-L7SP safety partner.
- Eliminates lithium batteries using 1756-ESMCAP or 1756-ESMCAPK energy storage modules.
- Features a front diagnostic display providing runtime operating information.
- Includes a pre-installed 1 GB 1784-SD1 Secure Digital non-volatile memory card.
TECHNICAL INFORMATION
Applications
- Safety systems requiring SIL 3 and Category 4 PLe certification.
- High-speed machine automation combining standard logic and functional safety tasks.
- Industrial network control using EtherNet/IP, ControlNet, or DeviceNet links.
TECHNICAL INFORMATION
Connections / Interfaces
- One built-in USB port supports programming and diagnostic communication.
- Backplane connection supports communication and power across ControlLogix 1756 chassis slots.
- Optional communication adapters include EtherNet/IP, ControlNet, and DeviceNet modules.
TECHNICAL INFORMATION
Installation Guidelines
- Install the controller into any available slot in a 1756 ControlLogix chassis.
- Connect the required 1756-L7SP safety partner module to complete dual-processor operation.
- Ensure adequate airflow to maintain the thermal dissipation rating of 8.5 BTU per hour.
TECHNICAL INFORMATION
Configuration Guidelines
- Program safety tasks exclusively using Relay Ladder Logic.
- Configure standard tasks using Ladder Logic, Structured Text, Function Block, or SFC.
- The 1756-L7SP safety partner configures automatically within the unified project file.
TECHNICAL INFORMATION
Compatibility
- Compatible with Allen-Bradley 1756 ControlLogix chassis hardware.
- Requires a 1756-L7SP safety module for safety standard compliance.
- Supports communication through 1756-EN2x, 1756-ENBT, 1756-CN2, and 1756-CNB adapters.
TECHNICAL INFORMATION
Lifecycle / Replacement Information
- Hardware controller redundancy is not supported by the 1756-L71S.
- Energy storage modules eliminate maintenance cycles required for traditional lithium batteries.
TECHNICAL INFORMATION
Compliance and Certifications
- Meets SIL 3 and Cat. 4/PLe standards when paired with a 1756-L7SP module.
TECHNICAL RESOURCES
Documentation
COMPATIBILITY
Compatibility & Replacement
COMPATIBLE MODELSCompatible with Allen-Bradley 1756 ControlLogix chassis hardware. Requires a 1756-L7SP safety module for safety standard compliance. Supports communication through 1756-EN2x, 1756-ENBT, 1756-CN2, and 1756-CNB adapters.
Verify compatibility against the exact Part Number, revision and manufacturer documentation before ordering.
PART VERIFICATION
Before You Order
Industrial automation parts can share similar model names, suffixes and revisions. Confirm the complete manufacturer Part Number before purchase.
01Check Part NumberMatch the complete ordering code on the existing unit.
02Confirm RevisionCheck suffix, hardware or firmware when applicable.
03Send a Label PhotoWe can review a clear label photo when identification is uncertain.
ORDERING PROCESS
From RFQ to Dispatch
1Submit Part Number2Verify Product Identity3Confirm Stock & Condition4Issue Quotation5Dispatch & Tracking
PRODUCT FAQ
Frequently Asked Questions
What safety rating does the 1756-L71S controller achieve?
The 1756-L71S meets SIL 3 and Cat. 4/PLe standards when paired with a 1756-L7SP safety partner.
Which programming languages are permitted for 1756-L71S safety tasks?
Safety tasks on the 1756-L71S controller must be programmed exclusively using Relay Ladder Logic.
Does the Allen-Bradley 1756-L71S support controller redundancy?
No, controller redundancy is not supported on the 1756-L71S controller.
What are the memory specifications of the 1756-L71S?
The controller contains 2 MB user memory, 1 MB safety memory, and 0.98 MB I/O memory.
