The 1756-OB16D ControlLogix Digital DC Output Module from Rockwell Automation is a high-performance 16-point 24V DC diagnostic output module designed for advanced industrial automation systems requiring real-time load diagnostics, precise switching, and high system visibility.
Unlike standard DC output modules, the 1756-OB16D provides built-in diagnostic capabilities, allowing engineers to detect field-side issues such as open load conditions, short circuits, and wiring faults. This makes it ideal for mission-critical manufacturing lines, safety-focused automation systems, and high-availability production environments.
It is widely used in modern ControlLogix architectures where predictive maintenance and fault transparency are essential.
Technical Specifications (Including Size & Weight)
| Parameter | Specification |
|---|---|
| Model | 1756-OB16D |
| Series | ControlLogix Diagnostic Output Modules |
| Module Type | 16-Point 24V DC Diagnostic Output Module |
| Number of Outputs | 16 outputs |
| Output Voltage Range | 19.2–30V DC |
| Nominal Voltage | 24V DC |
| Output Type | Sourcing transistor outputs |
| Diagnostics | Open load, short-circuit, load detection |
| Output Configuration | 2 groups of 8 points |
| Continuous Current per Point | 1.0 A |
| Signal Delay | < 1 ms typical |
| Short-Circuit Current | Up to 8–10 A (short duration protection behavior) |
| Isolation Voltage | 250V continuous (backplane & group isolation) |
| Backplane Current (5.1V DC) | ~250 mA |
| Power Dissipation | ~3.3–4.6 W |
| Field Power Requirement | External 24V DC supply required |
| Diagnostic Timestamp Accuracy | ±1 ms |
| Terminal Block | 1756-TBSH / 1756-TBCH |
| Operating Temperature | 0°C to 60°C |
| Storage Temperature | -40°C to 85°C |
| Humidity | 5%–95% non-condensing |
| Weight | ~0.35–0.60 kg |
Physical Dimensions
- Size (H × W × D): 145 × 35 × 140 mm
This standard ControlLogix single-slot form factor allows easy integration into existing chassis systems while maintaining space-efficient high-density I/O design.
Recommended Related Models
The 1756-OB16D is commonly used with:
- 1756-IB16 digital input module
- 1756-OA16 AC output module
- 1756-OB16 standard DC output module
- 1756-L71 / L73 ControlLogix processors
- 1756-EN2T EtherNet/IP communication modules
Popular Allen-Bradley ControlLogix Diagnostic & Output Modules
Within the ControlLogix family, commonly used related modules include:
- 1756-OB16D diagnostic DC output module
- 1756-OB16 standard DC output module
- 1756-OA16 AC output module
- 1756-OA16I isolated AC output module
- 1756-OW16 relay output module
These modules support scalable discrete control architectures with varying levels of diagnostics and protection.
