Method for splicing belt-type optical cables

Belt-type optical cables are best spliced using fusion splicing, which aligns and fuses multiple fibers simultaneously for a low-loss, permanent connection.

Overview of Splicing Techniques

Belt-type or ribbon optical cables contain multiple fibers arranged in a flat, parallel configuration. Splicing these cables requires precise alignment of each fiber to ensure minimal signal loss. The two main splicing methods are:

• Fusion Splicing: Uses an electric arc to melt and fuse fiber ends together, creating a continuous optical path with very low insertion loss (typically <0.1 dB) and high reliability . This method is preferred for belt-type cables because it can splice multiple fibers simultaneously using specialized ribbon fusion splicers.
• Mechanical Splicing: Aligns fibers within a mechanical holder with an index-matching gel bridging the gap. While faster and less expensive, it introduces higher signal loss (0.2–0.75 dB) and is generally used for temporary or emergency repairs .

Step-by-Step Fusion Splicing for Belt-Type Cables

1. Cable Preparation: Strip the outer jacket and buffer tubes carefully to expose the fibers. For ribbon cables, separate the fibers into individual ribbons if necessary .
2. Cleaning: Wipe fibers with isopropyl alcohol to remove dust and oils. Contaminants can cause high splice loss .
3. Cleaving: Use a precision cleaver to create flat, mirror-like fiber ends. Proper cleaving is critical for low-loss splicing .
4. Alignment: Place the fibers in the fusion splicer's V-grooves. Ribbon splicers align multiple fibers simultaneously, ensuring each fiber core is precisely matched .
5. Fusion: Activate the splicer to generate an electric arc, melting and fusing the fiber ends. The splicer monitors alignment and arc parameters to minimize loss .
6. Protection: After splicing, cover the joint with a heat-shrink sleeve or protective enclosure to maintain mechanical strength and environmental protection .
7. Testing: Measure insertion loss and return loss to verify splice quality. Low-loss splices ensure signal integrity across the network .

Best Practices

• Maintain a bending radius >30 mm during handling to prevent microbends .
• Avoid touching the fiber ends; oils from skin can weaken the splice .
• Use manufacturer-recommended consumables for sleeves and splicer electrodes to reduce failure rates .
• For long ribbon cables, consider mass fusion splicing, which can join 12–24 fibers at once, improving efficiency and consistency .

Conclusion

For belt-type optical cables, fusion splicing is the most reliable and efficient method, providing low-loss, permanent connections suitable for long-distance and high-speed networks. Mechanical splicing can be used for temporary or emergency repairs but is less suitable for permanent installations. Proper preparation, alignment, and protection are essential to ensure long-term performance and minimal signal degradation .