The Era of Fusion Splicing Is Coming

As fiber deployment has become mainstream, splicing has naturally crossed from the outside plant (OSP) world into the enterprise and even the data center environment. Fusion splicing involves the use of localized heat to melt together or fuse the ends of two optical fibers. The preparation process involves removing the protective coating from each fiber, precise cleaving, and inspection of the fiber end-faces. Fusion splicing has been around for several decades, and it’s a trusted method for permanently fusing together the ends of two optical fibers to realize a specific length or to repair a broken fiber link. However, due to the high costs of fusion splicers, it has not been actively used by many people. But these years some improvements in optical technology have been changing this status. Besides, the continued demand for increased bandwidth also spread the application of fusion splicing.

New Price of Fusion Splicers
Fusion splicers costs have been one of the biggest obstacles to a broad adoption of fusion splicing. In recent years, significant decreases in splicer prices has accelerated the popularity of fusion splicing. Today’s fusion splicers range in cost from $7,000 to $40,000. The highest-priced units are designed for specialty optical fibers, such as polarization-maintaining fibers used in the production of high-end non-electrical sensors. The lower-end fusion splicers, in the $7,000 to $10,000 range, are primarily single-fiber fixed V-groove type devices. The popular core alignment splicers range between $17,000 and $19,000, well below the $30,000 price of 20 years ago. The prices have dropped dramatically due to more efficient manufacturing, and volume is up because fiber is no longer a voodoo science and more people are working in that arena. Recently, more and more fiber being deployed closer to the customer premise with higher splice-loss budgets, which results in a greater participation of customers who are purchasing lower-end splicers to accomplish their jobs.

More Cost-effective Cable Solutions
The first and primary use of splicing in the telecommunications industry is to link fibers together in underground or aerial outside-plant fiber installations. It used to be very common to do fusion splicing at the building entrance to transition from outdoor-rated to indoor-rated cable, because the NEC (National Electrical Code) specifies that outdoor-rated cable can only come 50 feet into a building due to its flame rating. The advent of plenum-rated indoor/outdoor cable has driven that transition splicing to a minimum. But that’s not to say that fusion splicing in the premise isn’t going on.

Longer distances in the outside plant could mean that sticking with standard outdoor-rated cable and fusion splicing at the building entrance could be the more economical choice. If it’s a short run between building A and B, it makes sense to use newer indoor/outdoor cable and come right into the crossconnect. However, because indoor/outdoor cables are generally more expensive, if it’s a longer run with lower fiber counts between buildings, it could ultimately be cheaper to buy outdoor-rated cable and fusion splice to transition to indoor-rated cable, even with the additional cost of splice materials and housing.

As fiber to the home (FTTH) applications continue to grow around the globe, it is another situation that may call for fusion splicing. If you want to achieve longer distance in a FTTH application, you have to either fusion splice or do an interconnect. However, an interconnect can introduce 0.75dB of loss while the fusion splice is typically less than 0.02dB. Therefore, the easiest way to minimize the amount of loss on a FTTH circuit is to bring the individual fibers from each workstation back to the closet and then splice to a higher-fiber-count cable. This approach also enables centralizing electronics for more efficient port utilization. In FTTH applications, fusion splicing is now being used to install connectors for customer drop cables using new splice-on connector technology and drop cable fusion splicer.

A Popular Option for Data Centers
A significant increase in the number of applications supported by data centers has resulted in more cables and connections than ever, making available space a foremost concern. As a result, higher-density solutions like MTP/MPO connectors and multi-fiber cables that take up less pathway space than running individual duplex cables become more popular.

Since few manufacturers offer field-installable MTP/MPO connectors, many data center managers are selecting either multi-fiber trunk cables with MTP/MPOs factory-terminated on each end, or fusion splicing to pre-terminated MTP/MPO or multi-fiber LC pigtails. When you select trunk cables with connectors on each end, data center managers often specify lengths a little bit longer because they can’t always predict exact distances between equipment and they don’t want to be short. However, they then have to deal with excess slack. When there are thousands of connections, that slack can create a lot of congestion and limit proper air flow and cooling. One alternative is to purchase a multi-fiber pigtail and then splice to a multi-fiber cable.

Inside the data center and in the enterprise LAN, 12-fiber MPO connectors provide a convenient method to support higher 40G and 100G bandwidth. Instead of fusing one fiber at a time, another type of fusion splicing which is called ribbon/mass fusion splicing is used. Ribbon/mass fusion splicing can fuse up to all 12 fibers in one ribbon at once, which offers the opportunity to significantly reduce termination labor by up to 75% with only a modest increase in tooling cost. Many of today’s cables with high fiber count involve subunits of 12 fibers each that can be quickly ribbonized. Splicing those fibers individually is very time consuming, however, ribbon/mass fusion splicers splice entire ribbons simultaneously. Ribbon/mass fusion splicer technology has been around for decades and now is available in handheld models.

Conclusion
Fusion splicing provides permanent low-loss connections that are performed quickly and easily, which are definite advantages over competing technologies. In addition, current fusion splicers are designed to provide enhanced features and high-quality performance, and be very affordable at the same time. SunmaFiber provides various types and uses of fusion splicers with high quality and low price. For more information, please feel free to contact us at sales@SunmaFiber.com.