What Happens When One Output Channel Fails on a Critical DC Circuit?
A single shorted channel can halt an entire production line. The Allen-Bradley 1746-OBP16 solves this problem with integrated per-channel fuse protection. This SLC 500 Digital DC Output Module delivers sixteen sourcing outputs across a 20.4-26.4 Volts DC range. Each channel operates independently, so one fault never takes down the rest.
Product Overview
The 1746-OBP16 belongs to the Allen-Bradley SLC 500 series. It functions as a Digital DC Output Module with sixteen channels. The module outputs 24 Volts DC in sourcing configuration. It fits both fixed and modular style hardware. This flexibility makes it a practical replacement part for many existing SLC 500 installations.
Key Technical Parameters
The output voltage range spans 20.4-26.4 Volts DC source. Per-channel current reaches 1.5 or 1 amps, while total module current reaches 6.4 amps. The backplane draws 250 milliamps at 5 Volts. Step response measures 60 milliseconds in and 2.5 milliseconds out. These values suit high-current applications that demand fast switching and stable output.
Why Integrated Fuse Protection Matters
Each channel carries its own electronic fuse. When a short circuit or overload occurs, only that channel shuts down. The E-FEUSE LED on the front panel illuminates to signal the fault. Other channels continue operating without interruption. This design protects your process from total failure.
After you correct the fault, remove system power and reapply it. The module resets automatically and resumes control output. Plan this recovery behavior into your fail-safe operating conditions.
Replacement Fuse Details
Compatible replacement fuses include Littelfuse #322010, 10A or #332010, 10A. These maintain the UL/CSA rating. The Allen-Bradley fuse kit 1746-F8 contains five fuses. Replacing a fuse requires pulling the module from the chassis.
Where the 1746-OBP16 Fits Best
High-current DC applications benefit most from this module. Consider three common scenarios:
- Material handling systems – Conveyor solenoids and diverter gates draw significant current. The 6.4 amp module capacity handles multiple simultaneous outputs.
- Packaging machinery – Fast step response of 2.5 milliseconds out supports precise actuator timing. The 60 millisecond input response suits standard control cycles.
- Process valve control – Sourcing outputs drive DC solenoid valves directly. Per-channel fusing prevents a single valve fault from stopping the line.
Installation and Setup Guidance
Install the module in any single slot of an SLC 500 chassis. It works with both fixed and modular hardware styles. Use signal wires up to 2 mm² (14 AWG). Confirm your power supply delivers within the 20.4-26.4 Volts DC range. Follow the manufacturer’s wiring diagrams for all connections.
Maintenance and Reliability
Inspect the E-FEUSE LED indicators during routine checks. A lit LED signals a channel fault requiring attention. Keep spare fuse kits on hand to minimize downtime. The 1746-F8 kit provides five fuses per package. Schedule periodic inspections based on your operating environment. Dusty or high-temperature locations may require more frequent checks.
Compatibility and Integration
The 1746-OBP16 integrates directly with SLC 500 fixed or modular systems. It occupies one slot in the chassis. The module communicates through the SLC 500 backplane. No additional communication modules are needed for basic operation.
Selection Guide
Before purchasing, verify your system accepts SLC 500 modules. Confirm your application requires sourcing outputs within the 20.4-26.4 Volts DC range. Check that sixteen channels meet your I/O count. SpareTechPLC supplies genuine Allen-Bradley components with traceable part numbers. Contact SpareTechPLC to confirm current availability and lead times.
Frequently Asked Questions
Q: What happens when a channel short-circuits?
A: The integrated fuse isolates that channel. The E-FEUSE LED illuminates. Other channels keep running.
Q: How do I reset a faulted channel?
A: Remove system power, correct the fault, then reapply power. The module resets automatically.
Q: Which fuses work with this module?
A: Use Littelfuse #322010, 10A or #332010, 10A. The Allen-Bradley 1746-F8 kit contains five fuses.
Q: What wire size should I use?
A: Signal wires up to 2 mm² (14 AWG) are recommended.
Q: Does this module work in fixed-style SLC 500 hardware?
A: Yes. It installs in both fixed and modular style hardware.
