Description
The Allen-Bradley 1771-OBD is a 16-point DC output module designed for integration within the Allen-Bradley PLC-5 and 1771 universal I/O chassis architecture. This digital module operates within a voltage range of 10 to 60 VDC, providing reliable solid-state switching for industrial control devices such as solenoids, indicators, and motor starters. It requires compatibility with a Series B 1771 I/O chassis and supports flexible addressing configurations depending on system architecture.
Equipped with optical isolation between the logic side and the load side, the 1771-OBD ensures robust noise immunity and electrical protection in harsh manufacturing environments. Front-panel diagnostic indicators include a green module status LED, 16 individual red point status LEDs for direct logic-side verification, and a dedicated red fuse-blown indicator linked to onboard fusing protection. The module is engineered to handle moderate inrush currents while maintaining low on-state voltage drops for efficient power delivery.
Features
- 16 sourcing-type DC output channels operating at 10 to 60 VDC
- Delivers up to 2 A of continuous output current per point, with an 8 A maximum per module
- Handles surge currents up to 4 A per output for 10 ms, repeatable every 2 seconds
- Provides optical isolation rated at 1,500 VAC rms between I/O and backplane
- Features comprehensive diagnostic LED indicators for module health, individual channel status, and blown fuse alerts
- Low on-state voltage drop of 0.3 V max at 2 A for improved thermal and electrical efficiency
Applications
- Directly driving pilot lights, control relays, and solid-state actuators in PLC-5 architectures
- Switching inductive and resistive DC loads within manufacturing and process control skids
- Interfacing with complementary 1771 input modules requiring shared DC common references
- Expanding discrete output capacity in legacy 1771 universal I/O chassis configurations
Technical Specifications
| Parameter |
Specification |
| Brand |
Allen-Bradley |
| Module Type |
DC Output Module |
| Product Family |
PLC-5 / 1771 Universal I/O |
| Catalog Number |
1771-OBD |
| Outputs per Module |
16 (sourcing) |
| Operating Voltage Range |
10 to 60 VDC |
| Output Current Rating |
2 A max per output, 8 A max per module |
| Minimum Load Current |
2.5 mA per output |
| Max Surge Current |
4 A per output for 10 ms |
| Backplane Current Draw |
400 mA at 5 VDC (+/- 5%) |
| Signal Delay |
1.0 ms on or off |
| Isolation Voltage |
1,500 VAC rms |
| Country of Origin |
United States |
Compliance and Certifications
- UL Listed Industrial Control Equipment
- CSA Certified
- CE Compliant for applicable directives
- C-Tick marked