Published In January 2002
Advances in applications for fiber optic components, more than advances in the fiber itself, will drive the marketplace in the next 12 to 18 months. One of the latest new markets brings cabling out from under the office floor and into hazardous, harsh, pressurized, or wet environments. Like many past innovations, the world’s war zones serve as a proving ground for the technology. “Cable and connectors are growing away from the traditional, controlled environments like central offices and are going into atypical environments like battlefields, oil wells and, undersea exploration,” said Stanton Zeff, product manager with Fiber Systems International (FSI) (www.fibersystems.com, Richardson, Texas). In fact, many of the latest fiber connectivity products come from the battlefield where total reliability is required in a hostile environment. Unlike electrical connectors—where dirt and repeated use do not generally pose performance issues—fiber loses performance when contaminated by dust or scratching. Zeff said he sees applications for ruggedized fiber optic components—including hermetically sealed units—in many areas besides battlefields. Electrical contractors encounter these harsh conditions at construction sites, sports arenas, mining operations, and on factory floors. In each case, fiber must be run in dirty, vibration-prone environments with a lot of traffic. “In all of these situations, the idea is to minimize as much as possible any exposure to dust at every stage of the operation,” said Eric Leichter, applications engineer with Corning Cable Systems, (www.corningcablesystems.com, Hickory, N.C.). In fact, one of the first applications for the Corning Environmental Distribution Center, a sealed patch panel housing, was at U.S. Navy shipyards where they hook the shipboard local area networks (LANs) to the terrestrial demarcation point. The center houses the splice trays inside an enclosure, which is sealed from both air and water. It is common to find sealed panels in the manufacturing environment, too. Dirty and hot plant floors are hostile to normal networking products, said David Hall, Corning’s manager for marketing plans and systems. In such situations, he recommends running cable through metal-protected conduits. “As long as you use the proper cable and it is protected in a conduit, the terminations will remain dust-proof,” he said. Hall said that one key factor is having a spring on one of the two connections. This maintains the physical contact of the splice, making it difficult for dust to get between fiber ends. Sometimes, though, the system has to be literally tank proof. FSI’s Tactical Fiber Optic Connector Assemblies (TFOCA) are available in both single-mode and multimode configuration with electromagnetic interface (EMI) shielding available. The four- and 12-channel versions allow re-polishing without disassembling the connector. TFOCA is the original standard established by the U.S. Army and joint services for tactical deployable communications systems. TFOCA-II uses physical contact ceramic ferrules and a keyed terminus, or can be configured with an angle-polish terminus. TFOCA are designed for temporary deployment of fiber optic cable in construction zones or for temporary repairs. They are impervious to weather and even to vehicles running over them on dirt or asphalt. Leichter said that most commercial applications do not need the same degree of military hardening that designers first believed was required. He noted that the Corning ALTOS product is being used for outside-plant applications, such as coal mines, successfully. Manufacturing floors use it to tie industrial equipment to the back-office network. “Technologically, there is no limit to what we can do with fiber,” agreed Joe Berthold, vice president of standards for Ciena Communications, Inc. (www.ciena.com, Linthicum, Md.). Ciena is involved in more traditional communications applications, but Berthold sees futuristic standards development daily. In fact, he just completed his third term as technical chairman of the Optical Internetworking Forum (www.oiforum.com, Fremont, Calif.). “Getting the fiber to the end-user is the biggest problem,” Berthold said. Noting that only five to 10 percent of all U.S. businesses have fiber connections, he said the market has “unbounded potential.” “It is the cost of construction to get into the building and greedy landlords charging for access that are the real problems,” Berthold said. Telcos estimate a $50,000 cost for providing fiber access from the curb into a building. The cost of the actual fiber is only a relatively few dollars. The lion’s share is in equipment, labor, permits, and nonoptical considerations. Whether the application is military or commercial, Hall emphasized the need to use a degreaser or alcohol to remove cable gel and foreign particles. “Keep the fusion machine clean—you can’t have dirt in the V-grooves. Keep the lenses clean so the fibers align. Never set the machine in the dirt,” he said. Hall said it is best to work at a table. If possible, do the job from an air-conditioned truck designed for the purpose. It is better both for the fiber and for the worker. In any case, once it is time to strip and cleave the fiber, do not set it down until the job is done. That will ensure that a clean job is made of an otherwise dirty business. HARLER, a contributing editor to Electrical Contractor, is based in Strongsville, Ohio. He can be reached at (440) 238-4556 or firstname.lastname@example.org.