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Bulletin 1756 ControlLogix I/O Chassis-Based

ControlLogix I/O

Bulletin 1756 ControlLogix® I/O modules provide a full range of digital, diagnostic digital, analog, motion control, and specialty I/O to meet your application needs. You can use any of the I/O modules in the local chassis of a ControlLogix controller or in a chassis linked to a ControlLogix controller across ControlNet™ or EtherNet/IP™ networks.

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  • What's New
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  • Specifications
  • Software
  • Documentation
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  • Mounts in a ControlLogix® chassis
  • Requires either a removable terminal block (RTB) or a Bulletin 1492 wiring interface module (IFM) to connect all field-side wiring
  • Includes inherent time-stamping capabilities for sequence of events (SOE) applications
  • Offers comprehensive I/O diagnostics for detection of both system and field-side failures
  • Provides removal and insertion under power (RIUP) for ease of maintenance
  • Offers electronic keying to help prevent replacement errors
  • Includes I/O wizards in the Studio 5000™ Logix Designer application to enable quick and easy module configuration
  • Available with conformal coating to help protect in harsh environments

1756 ControlLogix Digital I/O Modules

  • Variety of voltages
  • 8 to 32 points per module
  • Isolated and non-isolated module types
  • Point-level output fault states
  • Direct-connect or rack-optimized communication
  • Field-side diagnostics on select modules

1756 ControlLogix Analog I/O Modules

  • Input, output, and combination modules
  • Thermocouple and RTD modules
  • On-board data alarming
  • Scaling to engineering units
  • Real-time channel sampling
  • Electronic module keying, software configurable
  • Mechanical RTB keying, user-defined
  • Per channel configuration for voltage, current or 2-wire transmitter current sourcing
  • Per channel configuration for either RTD or Thermocouple

1756 ControlLogix Specialty I/O Modules

  • Configurable flow meter modules
  • High-speed counter modules
  • Programmable limit switch modules

1756 ControlLogix Removable Terminal Blocks (RTBs)

  • Provide a flexible interconnection between plant wiring and I/O modules
  • Screw-clamp or spring-clamp terminations
  • Not shipped with I/O modules; you must order separately

Additional Information

Rockwell Automation Integrated Architecture Solutions provide the foundation to drive plantwide optimization efficiently and effectively, enabling you to respond competitively to the economy and changes in consumer demand.

The Rockwell Automation® PartnerNetwork™ offers complementary product solutions for 1756 ControlLogix I/O modules through the Encompass Product Reference program.

Enhanced, Isolated Analog I/O Modules Consolidate Capabilities and Provide Increased Functionality

This enhanced I/O module line replaces several I/O modules with just three modules. It improves functionality, performance, resolution, and accuracy, and also adds cost savings. Benefits include:

  • Includes advanced channel density from 6 to 8 points
  • Offers stability over entire temperature operating range
  • Requires no field calibration
  • Provides advanced precision with 24 bits of usable resolution
  • Allows timestamping in peer-to-peer applications
  • Includes synchronized input sampling across all modules
  • Offers 1 ms input sampling of floating point values
  • Provides per channel status and Fault LED annunciation
  • Supports RIUP and electronic keying
  • Offers cost savings via the need for less modules and fewer power supplies in the chassis
    1756-IF8I General Purpose Isolated Analog Input Module

    The 1756-IF8I general purpose isolated analog input module replaces the 1756-IF6I and 1756- IF6CIS modules, and provides faster performance and per channel configuration for voltage, current or 2-wire transmitter current sourcing.
    1756-OF8I General Purpose Current/Voltage Analog Output Module
    The 1756-OF8I general purpose current/voltage analog output module replaces the 1756-OF6CI and 1756-OF6VI modules, and provides faster performance and per channel configuration for either current or voltage.
    1756-IRT8I Combined Temperature Sensing Input Module
    The 1756-IRT8I combined temperature sensing input (thermocouple and RTD) module replaces the 1756-IT6I, 1756-IT6I2 and 1756-IR6I modules and provides faster performance and:
    • Per channel configuration for either RTD or thermocouple
    • Conformal coating to help protect in harsh environments
    • The 1756-CJC kit that is ordered separately when the 1756-IRT8I is used in Thermocouple mode and temperature correction is required. The kit includes two jumpers. 
    8-Channel Wiring System
    The wiring system solution for the 1756 8-channel analog modules  enables the wiring of more devices. The 6-channel wiring system will also function with the 8-point I/O modules, allowing the preservation of existing field terminations.
    • Decreases wiring time from the controller card to the terminal blocks
    • Provides additional capabilities for connections to the controller card via fusing and relays
    • Provides a more standard connection terminal block

Conformal Coating Products Can Help Protect Your Automation Systems

Conformal coating is now available on select ControlLogix® products to help protect your automation systems from hostile and harsh environments. Rockwell Automation tested these products for the equivalent of 10 years in an ISA G3 Group A classified environment.

These products are identified by the "K" suffix in the catalog number and they: 

  • Help to protect circuitry against exposure to pollution, moisture, temperature variation, salt spray, organic attack (fungus), and aggressive chemicals and vapors.
  • Offer improved product life cycle when exposed to corrosive environments by maintaining long-term surface insulation resistance (SIR) ensuring operational integrity of the assembly.


ControlLogix I/O Modules Technical Data1756-TD002


  • ATEX
  • C-Tick
  • CE Marked
  • CSA Certified
  • cULus Marked
  • FM Approved
  • TÜV

Certifications apply when product is marked. See our Product Certification site for Declarations of Conformity, certificates and other certification details.

Looking for Additional Information?

To find additional product information (CAD drawing files, 3D models, etc.) enter the complete catalog number (including dashes) below.


Use Studio 5000 Logix Designer from Rockwell Software® to design and configure your ControlLogix® system.

The controllers and modules you select, along with your network configuration, determine what additional software packages you need to configure and program your system. Additional required software may include RSNetWorx configuration software and RSLinx communication software.

Learn More

Additional software products are available from Rockwell Software.


Integrated Architecture BrochureIA-BR005
Extreme Environment (XT) System Product ProfileXT-PP001
ControlLogix Isolated Analog I/O Product Profile1756-PP020
ControlLogix Peer-to-Peer I/O Product Profile1756-PP018
ControlLogix System Selection Guide1756-SG001
ControlLogix I/O Modules Technical Data1756-TD002
ControlLogix Digital I/O Modules User Manual1756-UM058
ControlLogix Analog I/O Modules User Manual1756-UM009
More 1756 ControlLogix I/O Module publications in Literature LibraryAll Languages

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Product Certifications

See our Product Certification site for Declarations of Conformity, certificates and other certification details.

Configuration & Selection Tools

Other Resources

  • Electronic Data Sheets — Find DeviceNet™, ControlNet™, EtherNet/IP™, and network-independent EDS files.
  • Knowledgebase — Visit our online resource for technical information, support chat and forums, software updates, and product safety advisories/notices.