Making the smart decision

Before upgrading a copper plant to fiber optic cable, evaluate the alternatives. Fiber is great, but expensive. Any time a contractor is asked to pull new cable for a low-voltage installation, there are alternatives the client should hear.

“In my experience, it’s the fiber cable manufacturers who are pushing upgrading,” said Dino Kusulas, cabling expert with Fortune Consulting, (www.fciusa.com, West Long Branch, N.J.). A Building Industry Consulting Services International (BICSI) member, he stays on top of trends. He has not seen a stampede to fiber. Yet he agrees there are applications where fiber is great.

“A lot of people rely on copper because it is cheaper,” Kusulas said. But in a new build, he “would throw in fiber for future-proofing.” Indeed, TIA has a recent residential cabling standard that sanctions putting dark fiber in the walls in case fiber-to-the-home becomes a larger market.

By contrast, Kusulas said most commercial markets use the fiber as soon as the contractor installs it. “Fiber to the desktop is fine for bandwidth-hungry business applications like CAD/CAM or medical imaging,” he continued. “I haven’t heard of many businesses leaving fiber dark.”  

Edward Hester, vice president of durable goods with the Freedonia Group, (www.@freedoniagroup.com, Cleveland, Ohio) said fiber has some solid advantages, including its higher bandwidth capabilities, longer transmission distances, immunity to RFI (radio frequency interference) and EMI (electromagnetic interference), higher reliability and security, and lower maintenance costs relative to UTP copper.

Fiber has a major weight advantage in the structure. A fiber cable operating at 140 MB/s weighs close to 132 pounds per kilometer while the twisted pair cable equivalent will weigh about 16,000 pounds.

In some cases, it may not be necessary to pull new cable––fiber or copper. “Over the past 10 years, a lot of cable infrastructure has been put in. Especially in multitenant buildings, where there is steady turnover, a great deal of cable has been abandoned,” Kusulas noted. The problem is so big that the NEC recently made major changes to address abandoned cable.

Eventually, increased use of fiber cable may cut the amount of cable abandoned. If a tenant pulls out of a building, Kusulas recommends labeling abandoned network cable to increase the possibility of its reuse down the road.

Stretching that copper

Strong demand for multimegabit-per-second rates comes from small and medium-sized businesses. Today, this market is addressed primarily with DS1/T1 and symmetrical DSL services deployed mostly over existing copper loops.

Randy Nash, vice president of business development at Spediant Systems (www.spediant.com, Red Bank, N.J.) noted that many businesses want more bandwidth than a couple of DS1s/T1s provides. Others are beyond the distance and bandwidth limits of DSL technology.

Multi-Loop DSL (MLDSL) builds upon current standardized technology to address the issues involved in supporting smaller enterprise customers. The concept is simple: Use multiple pairs of copper and inversely multiplex the data across the pairs for greater reach and bandwidth. Rather than treat each copper pair individually, MLDSL treats multiple copper pairs as a logical bundle.

This approach delivers higher data rates over repeater-free longer loops, often also enabling service to customers previously unreachable. MLDSL can also make possible Ethernet and higher data rates over copper.

Down the road

Using fiber is not foolproof. Kusulas points out that most vendors are pushing a higher grade of fiber because advanced applications require cleaner, optically pure fiber. There may be a market for upgrading installed glass to better quality material.

Security may be one of the best-selling points for fiber installations. Hester noted that it is immune from tapping. “If the signal is tapped, light loss is unavoidable and the connection is shut down,” he said.

Copper is less desirable in manufacturing sites, where there can be EMI. “Anywhere there are motors, compressors, machinery or fluorescent lights, you can have problems with copper,” Kusulas warned.

Electrical contractors should note that fiber is safer to install and safer for many applications. “Since fiber optic cable carries no electrical current, it presents no spark hazard or danger due to electric currents and voltages,” Hester noted. The lack of spark hazard makes it the cable of choice for explosive environments such as refineries, chemical plants, mines or other industrial operations.

Using fiber requires competent work. Terminating fiber is a skill. Even the newer crimp-on connectors are not foolproof. Every installation involves stripping fibers, injecting adhesives and polishing the ends. EC

HARLER, a frequent contributor to SECURITY & LIFE SAFETY SYSTEMS, is based in Strongsville, Ohio. He can be reached at 440.238.4556 or curt@curtharler.com.