Tools for Fiber
Published: July 2007
Growing demand for broadband services offering the fastest possible speeds continues to drive deployment of fiber optic cable to enterprise customers of major telecommunications carriers and to a growing number of “private” fiber systems serving educational institutions, government complexes, commercial clients in areas not accessible to conventional networks, and even whole communities.
Electrical contractors with datacom capabilities are actively competing for work to make such fiber installations. Indeed, ELECTRICAL CONTRACTOR’s “2006 Profile of the Electrical Contractor” found that approximately 70 percent of respondents are involved in “communications systems and connectivity” work and that their interest in datacom and telecommunications training for the coming year is higher than in the previous 12 months.
Contractors with datacom experience recognize fiber projects require specialized skills and tools.
“Fiber optics has come a long way since the time when it had a ‘mystic’ quality known for difficulty of making installations and for high costs,” said Mario Rossi, Leviton senior product manager for fiber systems. “The technology has been improving quickly. And as high-performance networks require more stringent parameters, the industry releases new tools to keep pace with them.”
Good-quality tools used to terminate fiber optics are very versatile and can be used throughout virtually all fiber types, Rossi added.
“As examples,” he said, “a good-quality cleaver that guarantees less than 1-degree cleave angle can be used for single-mode and multimode fibers. Newer fusion splice machines are handheld and have internal software that allows for splicing different types of fibers.”
Rossi added that today’s products provide tools required to make different types of terminations and do them easier and at less cost than in the past.
Basic fiber connection tools include the following:
- Jacket strippers to remove the outer jacket on simplex and duplex fiber cables
- Serrated Kevlar cutters to cut and trim the Kevlar strength member directly beneath the jacket
- Fiber buffer strippers for removing acrylate coating from bare glass fiber
- Bare fiber cleaner swabs treated with an approved cleaning agent such as 99 percent isopropyl alcohol
- Scribes to score cable to fracture cleanly, leaving flat ends
- Cleavers to measure distance from the end of the coating to the point where the break will be made and scribes the glass so that it fractures at an angle of less than 3 degree
- Polishing tools, including a fixture to hold the connector perpendicular to polishing pad and film, polishing film to provide a consistent and uniform finish to the end face of the connector, and polishing pad
- Crimp tools for use with some types of connectors
- Optical and video inspection microscope for inspecting end face polish of fiber
- Visual faultfinders use a laser to locate breaks and faulty splices.
Basic connection methods include adhesive, mechanical, prepolished and pigtail. A fusion splicing machine is needed to connect the fiber being terminated to a fiber pigtail preassembled to a connector.
“Tools required depends on the style of connector being installed,” said Donald Stone, fiber optic design engineer, Kitco Fiber Optics. “There are epoxy connectors, preloaded adhesive connectors, anaerobic connectors (no oven required), and prepolished connectors. New ‘non-polish’ termination methods that are factory polished thus reducing the time it takes to complete the connector installation. Some techniques involve simply fusion splicing on ‘pigtails,’ thus eliminating the connector termination methods altogether.”
Anaerobic adhesives now are available in nonhazardous materials that allow easier transportation by air.
“There are always new strip tools, crimp tools and polishing pucks being developed that are universal to handle a variety of cable and connector types,” Stone added. “There are strip tools that will work with 3 mm and 2 mm jacketed cable types as well as being able to strip the various optical glass coatings. Crimp tools now have hex, round and a combination of both in one crimp die. Universal polishing pucks can now accommodate most of the 2.5 mm ceramic ferruled connectors.”
Inspection equipment, Stone added, is always improving, with newer inspection equipment going away from direct viewing with hand-held microscopes to small portable viewing on an LCD monitor using a microscope probe.
Jim McCandless, Ripley Co. fiber optic engineer, said outdoor cables require a rotary cable stripper or cable slitter to remove the heavy-duty outer jacket.
“Once this outer jacket is removed,” he said, “the hard inner tubes can be cut back with wire strippers, or opened with a buffer tube slitter, exposing the fibers. These fibers typically have 250-micron buffer coatings, which can be removed with a single-hole stripper sized to strip to 125 micron clad fiber. Some tools also allow for mid-span access of hard buffer tubes and access the individual strands of fiber. Kevlar shears are used to cut the Kevlar-strength members, which protect the fiber inside of the outer jacket.”
McCandless said that the market always is looking for tools that perform multiple operations rather than multiple tools for performing each function. However, because fiber tools tend to require a high level of precision, combining these functions can prove to be difficult when the goal is to produce a quality tool that does not have the potential to damage the fiber.
Handy Phelper, Greenlee Textron national sales manager for fiber optic equipment, observes that basic manual techniques for optical fiber termination have not changed, and no significant new tools have been added to product lines.
“However, there are several new automated machines for mass connector termination at a much higher cost. Also being [that] each tool has a specific purpose, there is not a trend towards multipurpose fiber tools,” he added.
Phelper said several types of cleavers are available to cleave the end of a fiber to a 90-degree end face.
“[The cleavers] can accomplish this with simple sapphire or diamond scribes or ‘stapler’ type and precision mechanical cleavers,” he said. “The type of connector will determine the crimping pliers required as well as if the connector is ‘dry’ or ‘wet.’ Dry connectorization is simply crimping the connector on the end of the fiber. The wet process requires epoxy and an oven for curing.”
Dan Payerle, datacom product manager for Ideal Industries, said that while techniques and tools for fiber installations are much the same as they have been, there has been more development into types of terminations that are taking some of the labor and time out of the installation process.
“Many tools and connectors are almost proprietary to their various manufacturers,” Payerle said. “However, our approach is to offer tools for fiber optic terminations that are generic and applicable to most standard types of connectors.”
With experience, fiber installers develop preferences for tools with characteristics that best fit the needs of their work.
“Because of the various dimensions of cables an installer will come across, the best jacket/buffer stripper is one that can accommodate all types of cables in a single tool,” said Payerle. “Most of these types of tools include at least two stripping points, one for the 3 mm outer jacket and another that removes the 900µ buffer and 250µ coating in a single pass. Some tools will include separate stripping points for the 900µ and 250µ which is somewhat more convenient for installers who routinely handle outside plant cable that does not have the 900µ buffer.”
Payerle added that plastic discs are fine for low-volume work but do wear and can wear unevenly if the installer does not rotate the disc during its lifetime.
“Plastic polishing discs typically have wear indicators so the installer can monitor it and discard if the disc is becoming uneven,” he explained. “Stainless discs have a much longer service life and resist uneven wear much better than plastic discs.”
A significant recent development is the way fiber terminations are inspected.
“It is estimated that 85 percent of all fiber failures are due to contaminated end faces, making it imperative to inspect and, if necessary, to clean end faces every time they are mated,” said Harley Lang, Fluke Networks product marketing manager. “An inspection microscope is necessary to confirm that the end face is polished and centered, and that it is not over-polished, under-polished, scratched or chipped. An inspection microscope is also essential for checking that the end face is clean of dust, dirt and human contaminants such as oil from a fingerprint.”
The video microscope is a fairly recent addition to the fiber installer’s tool kit and offers two key advantages over a manual, optical inspection microscope,” Lang said.
“First,” he explained, “the video camera does not contact the fiber end face. This eliminates the possibility of cross-contamination from the scope to the fiber. Second, the video camera does not transmit potentially harmful light rays from the fiber to the installer’s eye, as can happen with an optical scope. This means the installer can inspect active network links without risking eye damage.”
Sources providing information for this report agree that training is essential for fiber optic network installers, and Greenlee’s Phelper emphasized that most project owners will not do business with company’s whose installers are not certified.
Kitco’s Stone said there are several levels of fiber optic training offered in the commercial industry with the most common training for “Certified Fiber Optic Installer” (CFOI) and “Certified Fiber Optic Technician” (CFOT). A recognized organization for fiber optic certification is the Electronics Technician Association (ETA). Certified training is provided by many other organizations, including The Fiber Optic Association and from manufacturers of fiber installation tools. EC
GRIFFIN, a construction and tools writer from Oklahoma City, can be reached at 405.748.5256 or firstname.lastname@example.org.