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Written by: Larry Johnson
Fiber technicians require various tools for performing fiber cable For additional protection from rodents, many of these cable
 terminations. This article focuses on the various types of tools and the tasks they perform for both indoor and outdoor-style cables.
Cables used in outdoor installations have more cable elements than indoor types and there are two techniques for accessing the cables’ internal optical fibers. These are the traditional end-cuts where the ends of the cables are accessed for splicing or connectorization, and the “mid-entry”, a.k.a. express entry. Mid-entries are more common in service provider’s outside plant (OSP) cables where “fiber-rich” cables are accessed to “drop” optical fibers and/or buffer tubes along the cable’s route.
A variety of tools are required for cable preparation for terminations, while some are standard tools, such as electricians’ scissors, many are specific to the cable type and structure. Outdoor cables are designed to protect the internal optical fibers while also reducing the cable’s diameter and weight, and over the years, many different cable structures have been developed requiring different tools. The most common outdoor cable structure is the stranded loose tube cable. In this structure, individual fibers are placed inside individual color-coded buffer tubes wrapped around the cable’s internal strength member.
The second cable structure, is the “central” tube, a.k.a. uni-tube, where a single large buffer tube is in the middle of the cable and the fibers are grouped by the use of color-coded twine, or more commonly where ribbonized fibers are used, allowing for much higher fiber counts. These cables have two strength members that are between the central buffer tube and the outer cable jacket. Many types of fiber optic cables also include aramid yarn, a.k.a. KevlarTM, which requires KevlarTM cutters.
Figure 1: A mid-entry involved with removing a section of a cable's outer jacket to access buffer tubes and fibers.
types have metallic armoring which needs to be removed to access the internal cable structure. Armor-cutting tools, and/or snips, are required for cutting these elements.
Outdoor cables are typically a polyethylene (PE) material which is more difficult to strip than the standard polyvinyl chloride (PVC) used for indoor-rated cables. This requires a cable jacket cutter designed for the diameter of the cable jackets. Many tools have a function so that besides slitting the cable jacket, the tool’s blade can be rotated so ring cuts used in mid-entries can be performed. Armoring requires an armor jacket cutter.
Performing cable mid-entries requires a “Cable Ring” tool which allows cutting around the cables jacket, but also can slit the outer jacket by rotating the blade 90 degrees. Once the outer jacket, strength members, armor, and any aramid yarn have been removed, the focus turns to the buffer tubes, which further protect the 250-micron fibers or ribbons. Buffer tubes come in different sizes so tools are available to cut, or in the case of mid-entries, a buffer tube cutter is used to access (or shave off) the outer portion to access the internal fibers. While other tapes, ribbons, and powders are used for minimizing moisture intrusion, these do not require tools but cleaning solutions. Once the fibers or ribbons have been accessed, fiber strippers are used to remove the 250- or 900-micron coatings, and in the case of ribbons, the removal of the protective matrix coating.
  As many of these tools are specific to optical cables, care must be taken in keeping them clean of fiber and cable debris. Safety is also a key point. Make sure to follow safety guidelines from your organization and the tool manufacturer.
In our next article, we’ll discuss tools specific to splicing and terminations.
Larry Johnson was the founder of Light Brigade, is President of FiberStory and specializes in fiber optic consulting and training.
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