Comnet Universal Data Drop & Repeat 1 Fiber SM - FDX72S1

Comnet FDX72S1 Universal Data Drop & Repeat 1 Fiber SM

The Comnet FDX72S1 is a single-mode fiber data extender purpose-built for extending serial data (RS232, RS422, RS485) over long-distance fiber runs in unconditioned outdoor and roadside environments. This is a practical tool when you need to move sensor data, access control signals, or equipment telemetry across distances that would degrade copper cabling—fiber eliminates EMI susceptibility and supports runs measured in kilometers rather than hundreds of feet.

Overview

The FDX72S1 functions as a data drop and repeat device, meaning it can extend two independent serial data channels simultaneously while maintaining signal integrity across single-mode fiber. The unit meets NEMA TS-1 and TS-2 roadside equipment standards, making it suitable for traffic signal systems, highway toll collection, and other transportation-grade outdoor installations where environmental ruggedness is non-negotiable. Mounting options include shelf, rack, and DIN-rail configurations, so you can integrate it into existing cabinet layouts without custom fabrication.

Key Features

• Dual data channels with RS232/422/485 support: Two independent serial data paths means you can extend multiple sensor feeds or control signals on a single fiber pair—reducing the number of cables you need to pull and manage, especially valuable in long-distance roadside deployments where every cable run carries cost and maintenance burden.
• Single-mode fiber: Single-mode fiber reaches much farther than multimode (typically 10+ km vs. 2 km) with lower attenuation, so if your data needs to cross a large campus, a highway corridor, or a distributed industrial site, you avoid intermediate repeater stations that add complexity and failure points.
• Unconditioned out-of-plant/roadside rated: Built to operate in unheated, unshaded environments with temperature swings. No climate-controlled cabinet required—mount it in a roadside equipment box or utility enclosure and it will function across the full operating range, critical for traffic systems and remote sensor networks that can't depend on powered environmental control.
• NEMA TS-1/TS-2 compliance: These roadside equipment standards ensure the unit can withstand vibration, thermal cycling, and environmental stressors common to transportation and utility deployments. If your project touches highway or railway infrastructure, this certification often matters to the approving authority.
• Flexible mounting (shelf, rack, DIN-rail): Three mounting styles mean the FDX72S1 fits into different cabinet types—traditional 19-inch racks, compact utility enclosures with DIN-rail, or simple shelf installations. No custom brackets needed for most standard deployments.
• Transparent fiber extension: The unit extends serial data without protocol modification or encapsulation, so existing serial devices (sensors, controllers, access panels, traffic equipment) communicate as if they were on a native serial network. No firmware updates or driver changes needed on the devices themselves.

Integration & Compatibility

The FDX72S1 pairs with any RS232, RS422, or RS485 equipment—access control panels, environmental sensors, traffic controllers, VMS serial triggers, or legacy industrial automation devices. Because it operates at the physical layer and does not modify data, it is protocol-agnostic; Wiegand, Osdp, modbus, or proprietary serial commands pass through unchanged. Fiber termination requires industry-standard single-mode connectors (typically SC or LC, depending on your network infrastructure). Integration into surveillance or access networks typically involves pairing the data extender with a separate IP gateway or serial-to-Ethernet converter at the far end to bring serial data into a modern IP/VMS environment.

Frequently Asked Questions

Q: What is the maximum fiber distance the FDX72S1 can support?

A: Single-mode fiber can extend data many kilometers. The FDX72S1 itself is a transparent repeater, so distance depends on your fiber run and the light source used at each end. Consult the full datasheet or contact pre-sales engineering for your specific distance requirement.

Q: Can I mix RS232 and RS485 channels on the same unit?

A: The FDX72S1 provides two independent data channels. Each channel supports RS232, RS422, or RS485, so yes—you can run RS232 on one channel and RS485 on the other simultaneously.

Q: Is the FDX72S1 suitable for outdoor mounting?

A: The unit is rated for unconditioned out-of-plant and roadside environments, so it can be deployed outdoors. However, the unit itself should be installed in an appropriate IP-rated enclosure to protect the fiber connectors and electronics from direct rain and UV exposure.

Q: Do I need separate power supplies for both fiber ends?

A: Yes. The FDX72S1 is an active device and requires DC power at each end of the fiber link. The transmitter and receiver are separate units, each with its own power input.

Marty Allison

The FDX72S1 is one of those devices that solves a very specific problem: when you need to extend serial control and sensor data across distances where copper just doesn't work anymore. The single-mode fiber backbone means you're looking at 10+ kilometer reach without repeater chains—a real advantage in highway tolling, traffic signal networks, or utility SCADA systems spread across rural areas. The dual independent data channels let you consolidate multiple serial feeds onto one fiber pair, which cuts installation cost and future maintenance headaches.

Technical Highlights:

• Single-mode fiber with dual channels: Two RS232/422/485 data streams on one fiber pair eliminate the need to pull multiple cables across long distances. Single-mode reaches 10+ km with minimal attenuation, so you avoid intermediate repeater sites that add expense and failure points.
• NEMA TS-1/TS-2 roadside rating: Built to survive thermal cycling, vibration, and environmental stressors in unheated enclosures. If your project touches highway or transportation authority infrastructure, this compliance often determines whether the equipment passes commissioning.
• Protocol-transparent architecture: The FDX72S1 does not interpret or modify your data stream—Wiegand, RS485 modbus, legacy serial commands, or proprietary protocols all pass through unchanged. No middleware, no translation layers, no compatibility surprises.

Deployment Considerations:

• The FDX72S1 requires active power at both fiber ends—this is not a passive repeater. Factor dual power supplies or solar + battery backup into roadside cabinet design, especially if the remote site lacks utility power.
• Fiber connectors must be kept clean and protected. Deploy the unit inside an IP-rated roadside enclosure to shield connectors from moisture and UV. Field-terminated fiber runs are prone to problems if not properly sealed.

This device is the right pick for toll collection systems, distributed traffic controllers, or industrial sensor networks spanning multiple miles of campus or rural geography where Ethernet or copper serial runs would require intermediate powered repeaters. The transparent architecture means your legacy serial equipment stays in service without modification.