Description
The ALLEN BRADLEY 1786-RPFRXLB is a fiber-optic ring repeater module designed for extending ControlNet network segments in industrial environments.
Product Overview
The 1786-RPFRXLB extends ControlNet communication distances over fiber optics while maintaining ring topology for redundancy and fault tolerance. It supports extra-long distance fiber rings, enabling robust network architectures in large-scale automation systems.
ALLEN BRADLEY 1786-RPFRXLB
Technical Parameters
- Type: ControlNet fiber ring repeater module (extra-long distance variant).
- Power requirements: Backplane-powered, typically 570 mA at 5V DC maximum.
- Communication rate: 5 Mbps coaxial/fiber compatible.
- Fiber type: 200/230 micron HCS (hard-clad silica) or equivalent multimode fiber.
- Distance capability: Extra-long ring segments up to several kilometers depending on fiber quality and connectors.
- Optical budget: Supports up to 4.2 dB total light loss including splices and terminations.
- Connectors: Dual ST fiber optic ports for ring configuration (Channel 1 and Channel 2).
- Indicators: Status LEDs for module health, channel status, and network activity.
- Environment: 0…60 °C operating temperature, suitable for control cabinets.
- Mounting: DIN rail compatible via repeater adapter backplane.
Manufacturing Origin
Manufactured by Allen-Bradley (Rockwell Automation), based in Milwaukee, Wisconsin, USA. The product is part of the ControlNet family designed for North American and global industrial automation markets.
Application Fields
- Large-scale process control plants requiring extended fiber network segments.
- Ring topologies for redundant communication in critical safety systems.
- Factory automation with distributed I/O over long distances.
- Power generation and utility networks needing fault-tolerant cabling.
- Oil & gas facilities with hazardous area fiber optic requirements.
ALLEN BRADLEY 1786-RPFRXLB
Technical Description
The module creates a redundant fiber ring by connecting two fiber segments that automatically reconfigure upon cable fault or power loss. It regenerates optical signals for extra-long distances while preserving ControlNet deterministic performance. Integrated diagnostics monitor fiber integrity, power levels, and ring status through front-panel indicators.
Usage Instructions
Installation requires a 1786-RPA/B repeater adapter mounted on DIN rail.
- Attach module to repeater adapter backplane (maximum two RPFRXLB modules per adapter due to power limits).
- Connect fiber cables to Channel 1 and Channel 2 ST connectors, ensuring proper bend radius and tension limits.
- Verify LED status: Module OK (green), Channel Status (green when active).
- Integrate into ControlNet network planning for segment length and repeater count limits.
- Test ring redundancy by disconnecting one fiber segment and confirming network continuity.
Similar Models
Five related ControlNet repeater modules include:
- 1786-RPFRLB (long-distance fiber ring repeater).
- 1786-RPFS (short-distance fiber repeater).
- 1786-RPFM (medium-distance fiber repeater).
- 1786-RPCD (dual copper repeater).
- 1786-RPA/B (repeater adapter base unit).
