How to split cables in an optical distribution box

Optical cables are split at a distribution box using fiber optic splitters, which divide a single incoming signal into multiple outputs, with careful cable management to ensure signal integrity.

Understanding Fiber Optic Splitters

A fiber optic splitter is a passive device that divides one incoming optical signal into multiple outputs without requiring power, making it ideal for FTTH networks . Splitters can be of two main types:

• PLC (Planar Lightwave Circuit) Splitters: Provide even signal distribution, commonly with ratios like 1:4, 1:8, 1:16, 1:32, or 1:64 .
• FBT (Fused Biconical Taper) Splitters: Made by fusing fibers together, allowing customizable splitting ratios . Splitters can be used in centralized configurations (all splitters in one box, easy to reassign connections) or distributed configurations (splitters placed closer to users, addresses fixed), .

Step-by-Step Process for Splitting Cables

1. Prepare the Optical Cables: Inspect each cable for damage, clean connectors, and ensure proper stripping of the protective sheath to expose the fiber core .
2. Install the Splitter in the Distribution Box: Place the splitter in a secure slot or holder inside the optical distribution box. Ensure it is protected from bending or stress, as excessive bending can cause signal loss .
3. Connect the Input Fiber: Attach the incoming fiber from the OLT (Optical Line Terminal) or upstream network to the splitter's input port. Use proper connectors and ensure a secure fit .
4. Connect Output Fibers: Route the output fibers from the splitter to the designated ports in the distribution box, leading to individual ONUs (Optical Network Units) or subscriber endpoints. Maintain organized loops to prevent tangling and minimize bending .
5. Label and Document Connections: Clearly label each output fiber to match the subscriber or endpoint it serves. This simplifies maintenance and troubleshooting .
6. Test Signal Quality: After connections, use an optical power meter or OTDR (Optical Time-Domain Reflectometer) to verify signal strength and ensure minimal loss across all outputs .

Best Practices

• Avoid sharp bends; maintain the minimum bend radius specified by the fiber manufacturer.
• Use cable management trays or guides inside the box to keep fibers organized.
• For high-density areas, consider cascaded splitting: a primary splitter (e.g., 1:8) feeds secondary splitters (e.g., 1:8) to reach multiple endpoints efficiently .
• Choose the splitter type and ratio based on user density and distance to endpoints to balance signal strength and fiber usage . By following these steps and best practices, optical cables can be effectively split at a distribution box, ensuring reliable signal distribution and easy maintenance in FTTH networks.