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Fiber installation techs keep campus connected

Telecommunication installation techs Destry Mulleneaux and Christian Johnson, the U’s fiber-optic cable experts.Most of us wake with the expectation that once we get to campus, our computers will power up, our devices will connect to the network and our phones will work.

We rarely consider the secret highway of fiber-optic cables – winding behind walls and snaking underground – but that’s precisely where those expectations are met.

“In this day of expanding technology, everything runs off fiber,” said Tim Goodale, senior product manager of Pathway Engineering in UIT Communications Infrastructure. “Fiber feeds the wireless access points that connect all of our smart devices to the internet and cloud, it connects all of the wired ports we plug our phones, computers, and TVs into. Fiber even connects elevators, time card machines, and fire alarms on campus. At the hospital, it connects patient monitoring equipment, life support systems, and data storage. In short, fiber provides all the technology connections that light up our lives.”

Keeping the fiber highway humming over 1,535 acres are telecommunication installation techs Destry Mulleneaux and Christian Johnson, the U’s fiber-optic cable experts.

“Destry and Christian are two of less than a handful of fiber technicians in the state of Utah who are trained and have experience installing the type of Air Blown Fiber (ABF) that’s used on campus,” Goodale said.

On the morning of March 1, the men are dispatched to north campus to install ABF from the Energy and Geoscience Institute to the Dumke Health Professions Education building, about 2,000 feet south on Wakara Way.

They cart in two 90-pound canisters of compressed nitrogen, each pressurized at 2,000 pound-force per square inch (psi), and a 5,000-feet bundle of FutureFLEX® ABF.

The job begins and ends in a room not much larger than a closet – site of the main distribution frame (MDF), a cable rack that interconnects and manages telecomm wiring.

ABF succeeds the old way of installing cable – pulling it with Muletape, a time- and labor-intensive process. According to the FutureFLEX website, with ABF, two people can install one mile of cable in 45 minutes. Using the conventional pulling method, it might take up to eight people two or more days to pull a single mile of cable.

Two modes of force are in play in ABF operations. The casing that sheaths the fiber bundle is dimpled like a golf ball, allowing it to catch the air and grip a spinning rubber drive wheel. The second force is the “air” itself (dry nitrogen in this case) which propels the fiber at speeds of 100 to 150 feet-per-minute, though Johnson dials it down to make the feed more gradual and reduce the risk of snagging.

Unfortunately, a half hour into the job, at about the 500-foot mark, the fiber gets caught up. Johnson tries a couple “bumps” – quick taps of air – to clear the obstruction before concluding: “We’re stuck.”

Johnson heads outside to the nearest manhole to meet up with Mulleneaux, who climbs down to get a closer look. No apparent blockage there, or at the next manhole, but they spot the problem at the third – the fiber is caught on a coupler.

Back in business, Johnson heads back while Mulleneaux continues on to the final destination. Once the fiber arrives, Mulleneaux calls Johnson to let him know.

All in all, a successful feed, but the men are just beginning the meticulous process of stripping, cleaning, cleaving and fusing the fibers – Johnson’s “favorite part of the job.”

Telecommunication installation tech Christian Johnson points to fiber-optic cables feeding into the building's main distribution frame (MDF).The tubes that carry and protect Air Blown Fiber (ABF) are transparent.The 5,000-feet bundle of FutureFLEX® ABF, set up and ready to be fed.The casing that sheaths the fiber bundle is dimpled like a golf ball, allowing it to catch the air and grip a spinning rubber drive wheel.Unfortunately, but not unusually, the feed is interrupted by a snag. Johnson and Mulleneaux go to the nearest manhole to investigate.Mulleneaux takes a closer look.Not finding an obvious cause for the interruption there, the men head to the next manhole.Johnson removes the manhole cover.Not finding the issue at the second manhole, the men continue to a third manhole, where Johnson spots the problem.The fiber is caught on a coupler.After the feed is complete, Johnson starts the meticulous process of stripping, cleaning, cleaving and fusing the fibers. To reach the fiber bundles, a clear plastic “rip cord” helps Johnson peel back the outer sheath.But he prefers ringing the end with a stripping tool to get a cleaner edge.Inside the tough outer jacket are individual, tightly-compacted fibers. The ABF that Mulleneaux and Johnson are using actually consists of 24 fibers, four each of six-fiber bundles.One bundle might include blue, orange, green, brown, slate and red while another may contain relative colors like rose and aqua.“If you’re color-blind, forget about it,” Johnson says.Johnson “fans out” the six fibers in each bundle. The opposite of running scissors down a length of ribbon, he runs his fingers down the fibers to spread them and get a better look at the colors.Johnson will join the optical fibers to a fiber “pigtail” that has an unterminated fiber on one end and a factory-installed Angle Polished Connector (APC) on the other.The connector clicks into a fiber termination unit (FTU) coupler panel. Now, each individual length of fiber must be fused to the factory-polished fiber end of the pigtail.The glass tips on the fusible ends are not much thicker than a human hair, which Johnson wipes with a 96 percent alcohol solution to remove any residue. He snips each end with a cleaving machine that contains a cutter made of ruby, a finer edge than any metal, similar to a diamond. Both ends have to be precisely cleaved and aligned or the fusion-splicing machine will reject the splice.The splicing machine uses optical core alignment, which means the two fibers are illuminated from two directions, 90 degrees apart. Two small video cameras take the images. The software recognizes the core of the fibers and automatically aligns them using movable stages. Clamped down and covered, electrodes fire to create an arc that fuses the ends together. Without the safety cover, the tech would be blinded. After a few initial mis-alignments, the splice finally takes.The attachment process is vital to the success of the telecommunications network. Done well, it allows optical signals to pass with low attenuation and little return loss.“And that’s that,” Johnson says. Simple, right? Hardly, but in the trusted hands of the U’s fiber pros, it sure seems like it.

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Last Updated: 7/22/20