Monthly Archives: August 2011

Fiber Splicing Basics


In fusion splicing, the cores and cladding of the two fibers are actually melted together. The core is the central part of the fiber and has a very small diameter. The core is where the light travels through the fiber.  Because of this, it requires a very precise instrument to align and then weld the cores in such away to let them most light pass through the point of joining. The diameter of single mode fiber is about 1/100 of a millimeter, and for multi-mode fiber the diameter is 1/16 of the millimeter. For comparison, a human hair is about 1/8 of a millimeter in diameter. Because of the small diameter of the fiber core, it is difficult to position two fibers so that their cores line up nearly perfectly. The light cannot pass through if the cores are not lined up just right. In addition, the heating of the fiber must be very exact. If not enough heat then the two ends will not melt together. Conversely, if too much heat is applied then the fiber may droop or deform and again not line up properly. Best fusion splicers on the market today are automated. That is, when you put two properly stripped and cleaved fibers and these devices, they automatically line up the fibers, use them together, and measure the DB loss at the splice. The automated fusion splicers are designed to work with many different types and combinations of fibers. It is possible to splice different types of fibers, including the most common types single and multi-mode fibers using the splicer’s preprogrammed factory settings. Manual operation is still possible when necessary. Splicing Procedure Stripping the fiber: The splicing process begins by preparing each fiber for fusion. Fibers are prepared by stripping away all of the protection, including any jacket and sheath. The fibers are then stripped of their protective polymer coating in preparation for fusion splicing. Thermal strippers are best as they minimize the risk of damage to the fiber but the most common fiber strippers look almost identical to handheld wire strippers. Cleaning the fiber: The bear fibers are cleaned using alcohol and wipes, or an ultrasonic cleaner. Cleaving the fiber: Once only beer glass remains, the fibers are then cleaved to expose a predetermined length of bare fiber. Most fiber optic cleavers on the market today use a tungsten carbide wheel or diamond blade to score, or ‘nick’, the fiber. This intentionally creates a microscopic fracture in the side of the fiber where the break is to result. Proper tension is used to pull the fiber, or a force is applied perpendicular to the longitudinal axis causing a controlled break and producing a perfectly flat endface. This is called the score-and-break, or scribe-and-break method. Properly done, cleaving leas a mirror-like finish. It should be perfectly flat and perpendicular to the axis of the fiber. Fusion splicing: The fibers are then clamped into the fusion splicers fiber holders, which may be fixed or removable dependent on the type of splicer. Today’s best fusion splicers will automatically identify the type of fibers being used and select the appropriate splice program, or allow manual control. The amount of loss allowed in the fiber-optic network due to splice or connector losses, the more sophisticated the fusion splicer required. Simple splicers let the fibers align themselves during the fusion while more sophisticated machines and just the both fiber sites to match each other. There are two basic types of fusion splicing systems in today’s fiber splicing machines, Core Alignment and Cladding Alignment. Cladding AlignmentCore Alignment Core Alignment: The technique associated with the more expensive Core Alignment or Profile Alignment System (PAS) splicers use the fiber’s core to align the fibers in the splicer. Cladding Alignment: The other commonly used method is called Cladding Alignment or Fixed V-Groove Alignment and uses the precision v-grooves to help align the fibers. With this method instead of the fibers core it’s the outside or cladding which the splicer uses to align the fibers. Protecting the fiber:Protective Splice Sleeves Once the splice is completed the splice protection sleeve is slid over the fused area and bare fiber and into the heat oven.   Tips for maintaining your fusion splicer Fusion splicers are expensive precision tools and must be cared for as such. Repairs can be very expensive, especially with the Japanese models. Fujikura, Fitel and Sumitomo have an uncommon control over pricing, distribution and repairs. Be prepared to pay substantially over the life of the splicer for factory maintenance. This is a good reason to take excellent care of your fusion splicer. One of the biggest concerns here is cleanliness. Electrodes Remember, it is not necessary to pay the exorbitant manufacturer prices for replacement fusion splicer electrodes. In several examples, we have confirmed that at least a couple of the splicer manufacturers sell the same electrodes as sold by and other vendors. Do not pay $90-$125 when you can get them  same or better quality for half the price. Cleaning Carefully clean the mirrors and camera lenses to ensure proper splicing operations. Be sure to use only 99.9% isopropyl alcohol or an approved product designed specifically for cleaning fiber optics. Dirt removal in the precision v-grooves is imperative. You can use a piece of scrap fiber to scrape out any debris in the v-grooves or fiber holders. Caution: Using canned air to blow out a fusion splicer can cause dirt or shards of glass to sandblast mirrors and lenses, as well as in bed this debris into motors, bearings or other moving parts.  

Ericsson FSU-975 User Manual

User guide for Ericsson 975 fusion splicer. [pdf issuu_pdf_id=”110823200631-7fce30086f7f4b58a997f65a039a0c91″]

Ericsson FSU-995fa User Manual

[pdf issuu_pdf_id=”110823200628-b1159353936e4c77a134b45b106594f9″]

Ericsson FSU-Series Service Manual

This manual was only available through one of Ericsson’s traning classes on the FSU series splicers.  [pdf issuu_pdf_id=”110823200626-b13effd94dc94d8aa246ede3bf600ad4″]

Fujikura FSM-17s User Manual

[pdf issuu_pdf_id=”110823200623-4aa767529f9c474a90e02c54960dde1f”]

Fujikura FSM-18s User Manual

[pdf issuu_pdf_id=”110823200620-2009be861cba4a87a42e3a582ae26b90″]