Overview
The Allen-Bradley 1756-OB16I is a ControlLogix isolated DC output module featuring 16 individually isolated output points. This module operates at a voltage category of 12/24VDC in sinking or sourcing configuration. It is directly installed to a 1756 local or remote chassis. The 1756-OB16I /A variant includes point-level output fault management, making it ideal for applications requiring high reliability and fault tolerance.
Key Features
- Sixteen individually isolated outputs (16)
- Operates in sinking or sourcing configuration
- Output channels feature configurable safe state position when the controller’s mode is changed to Program and Controller fault
- Outputs-to-backplane continuous isolation voltage of 250V and output-to-output continuous isolation voltage of 125V
- Multiple communication formats including output data, listen-only output data, rack optimization, listen-only rack optimization, and scheduled output data
Technical Specifications
- 10-30 V DC, 16-point ControlLogix digital output module
- 1 A outputs that are individually isolated
- 1 mA per point minimum load current, 1.2V DC at 2 A maximum on-state voltage drop, and 0.5 mA per point maximum off-state leakage current
- Output delay time of a maximum of 1 ms from off to on and a maximum of 2 ms from on to off
- Power dissipation of 3.6W at 60 Degrees Celsius (maximum) and thermal dissipation of 12.28 BTU/hr
- Operating temperature range of 0 to 60 Degrees Celsius and non-operating temperature range of -40 to 85 Degrees Celsius
- Routine-tested at 1350V AC for 2 seconds
Typical Applications
The 1756-OB16I is widely used in industrial automation for:
- Discrete signal control in manufacturing and packaging systems
- Machine safety interlocks and fault state management
- Process control applications requiring isolated output channels
- Multi-voltage machine control with independent 12/24 VDC sources per point
- High-reliability systems where output isolation is critical
Compatibility & Replacements
Compatible With
- Allen-Bradley ControlLogix chassis (1756 backplane)
- ControlLogix processors (L70, L72, L73, L75, etc.)
- Studio 5000 Logix Designer software
- EtherNet/IP networks via ControlLogix gateway modules
- Remote Terminal Blocks 1756-TBCH and 1756-TBS6H (36-pin)
Replaces / Drop-In Replacement For
Verify specific replacement compatibility with your system integrator before ordering, as the 1756-OB16I replaces earlier discrete output modules but may require firmware updates in legacy systems.
Works With
- Studio 5000 Logix Designer (RSLogix 5000)
- ControlLogix Producer/Consumer messaging
- Integrated Architecture I/O via backplane
- External Isolated Fieldmount (IFM) protection modules
