I recently watched my coworker disassembling a computer only using one tool. Was it the right tool to do the job? Yes and no. It was the tool he had… it worked, however, there is certainly definitely more than one tool available that will make the work easier! This example is definitely one which many fiber optic installers know all too well. As a gentle reminder, what percentage of you might have used your Splicer’s Tool Kit (cable knife/scissors) to eliminate jacketing or even slit a buffer tube and then make use of the scissors to hack away at the Kevlar? Did you nick the glass? Did you accidentally cut through the glass and have to start over?
Correctly splicing and terminating SZ stranding line requires special tools and methods. Training is essential and there are lots of excellent causes of training available. Usually do not mix your electrical tools with your fiber tools. Utilize the right tool to do the job! Being familiar with fiber work will end up increasingly necessary as the value of data transmission speeds, fiber for the home and fiber for the premise deployments still increase.
Many factors set fiber installations apart from traditional electrical projects. Fiber optic glass is extremely fragile; it’s nominal outside diameter is 125um. The slightest scratch, mark or perhaps speck of dirt will affect the transmission of light, degrading the signal. Safety is important simply because you work with glass that will sliver in your skin without having to be seen by the eye. Transmission grade lasers are incredibly dangerous, and require that protective eyewear is a must. This industry has primarily been coping with voice and data grade circuits that may tolerate some interruption or decelerate of signal. The person speaking would repeat themselves, or perhaps the data would retransmit. Today we are working with IPTV signals and customers that will not tolerate pixelization, or momentary locking in the picture. All of the situations mentioned are cause for the consumer to find another carrier. Each situation could have been avoided if proper attention was provided to the strategies used when preparing, installing, and looking after fiber optic cables.
Having said that, why don’t we review basic fiber preparation? Jacket Strippers are used to remove the 1.6 – 3.0mm PVC outer jacket on simplex and duplex fiber cables. Serrated Kevlar Cutters will cut and trim the kevlar strength member directly under the jacket and Buffer Strippers will remove the acrylate (buffer) coating from the bare glass. A protective plastic coating is applied towards the SZ stranding line following the drawing process, but prior to spooling. The most typical coating is really a UV-cured acrylate, that is applied in two layers, resulting in a nominal outside diameter of 250um for that coated fiber. The coating is very engineered, providing protection against physical damage brought on by environmental elements, like temperature and humidity extremes, being exposed to chemicals, point of stress… etc. while minimizing optical loss. Without this, the maker would struggle to spool the fiber without having to break it. The 250um-coated fiber is the foundation for many common fiber optic cable constructions. It is usually used as is, especially when additional mechanical or environmental protection is not needed, such as within optical devices or splice closures. For extra physical protection and simplicity of handling, a secondary coating of polyvinyl chloride (PVC) or Hytrel (a thermoplastic elastomer which has desirable characteristics to use as being a secondary buffer) is extruded within the 250um-coated fiber, improving the outside diameter as much as 900um. This type of construction is called ‘tight buffered fiber’. Tight Buffered could be single or multi fiber and they are seen in Premise Networks and indoor applications. Multi-fiber, tight-buffered cables often are used for intra-building, risers, general building and plenum applications.
‘Loose tube fiber’ usually is made up of bundle of fibers enclosed in a thermoplastic tube known as a buffer tube, that has an inner diameter that is slightly larger than the diameter in the fiber. Loose tube fiber includes a space for that fibers to expand. In particular weather conditions, a fiber may expand then shrink over and over again or it may be subjected to water. Fiber Cables will sometimes have ‘gel’ within this cavity (or space) yet others which can be labeled ‘dry block’. You can find many loose tube fibers in Outside Plant Environments. The modular style of loose-tube cables typically holds as much as 12 fibers per buffer tube using a maximum per cable fiber count of more than 200 fibers. Loose-tube cables could be all-dielectric or optionally armored. The armoring is used to safeguard the cable from rodents including squirrels or beavers, or from protruding rocks in a buried environment. The modular buffer-tube design also permits easy drop-away from teams of fibers at intermediate points, without interfering with other protected buffer tubes being routed to other locations. The loose-tube design also helps in the identification and administration of fibers within the system. When protective gel is found, a gel-cleaner such as D-Gel is going to be needed. Each fiber is going to be cleaned with the gel cleaner and 99% alcohol. Clean room wipers (Kim Wipes) are a wonderful decision to use with all the cleaning agent. The fibers inside a loose tube gel filled cable will often have a 250um coating so they are definitely more fragile than a tight-buffered fiber. Standard industry color-coding can also be utilized to identify the buffers as well as the fibers in the buffers.
A ‘Rotary Tool’ or ‘Cable Slitter’ could be used to slit a ring around and thru the outer jacketing of ‘loose tube fiber’. As soon as you expose the durable inner buffer tube, you can use a ‘Universal Fiber Access Tool’ which is designed for single central buffer tube entry. Used on the same principle since the Mid Span Access Tool, (that enables access to the multicolored buffer coated tight buffered fibers) dual blades will slit the tube lengthwise, exposing the buffer coated fibers. Fiber handling tools for instance a spatula or perhaps a pick can help the installer to get into the fiber needing testing or repair. After the damaged fiber is exposed a hand- stripping tool will be utilized to eliminate the 250um coating to be able to work with the bare fiber. The next step will be cleaning the fiber end and preparing it to be cleaved. A great cleave is probably the most important factors of producing a low loss on a splice or perhaps a termination. A Fiber Optic Cleaver is actually a multipurpose tool that measures distance from the end from the buffer coating to the stage where it will be joined plus it precisely cuts the glass. Always remember to utilize a fiber trash-can for your scraps of glass cleaved off the fiber cable.
When performing fusion splicing you might need a Fusion Splicer, fusion splice protection sleeves, and isopropyl alcohol and stripping tools. If you are using a mechanical splice, you will require stripping tools, mechanical splices, isopropyl alcohol and a mechanical splice assembly tool. When hand terminating Sheathing line you will need 99% isopropyl alcohol, epoxy/adhesive, a syringe and needle, polishing (lapping) film, a polishing pad, a polishing puck, a crimp tool, stripping tools, fiber optic connectors ( or splice on connectors) and piano wire.
When a termination is complete you need to inspect the end face in the connector using a Fiber Optic Inspection Microscope. Making sure that light is to get through either the splice or yphlby connection, a Visual Fault Locator can be utilized. This device will shoot a visible laser down the fiber cable to help you tell there are no breaks or faulty splices. When the laser light stops on the fiber somewhere, there is most likely a rest in the glass at that time. When there is more than a dull light showing at the connector point, the termination was not successful. The sunshine must also pass through the fusion splice, when it fails to, stop and re- splice or re-terminate.