No data communications project is complete until multiple tests confirm that it will meet the network plan’s specifications and building owner’s expectations. To conduct these tests, copper and fiber optic cable testing tools have evolved to meet the demands of today’s structured wiring systems.
“There was a time, not so long ago, when voice/data/video (VDV) installations would have to include multiple cable systems for different uses. A legacy of this can be seen in many longer established organizations,” said Peter Dennis, product portfolio manager for Communications at Megger.
“There would be a single twisted copper pair for the telephone, a multiple twisted copper pair system for the main data network and a coax system for video such as CCTV, CATV and internal video conferencing,” Dennis said. “All of these systems would have their own standards, components and installation methods and would require three highly skilled technicians, one to install each system.
“Modern improvements mean that the technological gap between these areas has become blurred to the point where a single cable installation can be used to provide all of these services and more,” he said.
According to Dennis, most modern VDV systems are installed using a structured approach, ensuring consistency across the system and allowing the best possible efficiency. This structured cabling approach is a building or campus communications cabling infrastructure that consists of a number of standardized smaller elements (hence structured) called subsystems. Structured cabling can encompass either copper or fiber cabling and can be separated into six main subsystems, each of which has its own requirements but can all share the same basic structured methodology.
“There are many copper wire test sets on the market each having their own functionality and designated use,” Dennis said. “An assortment of instruments may be required to cover all testing requirements so the technician must consider availability of suitable instruments accordingly.”
The five main sectors of test instrument built specifically for communications testing are: wiremap, qualification, validation, analysis and certification, he said. There are a growing number of combined test instruments available that contain all of the test capabilities for verifying and potentially certifying a VDV installation. Some even have the capability, with an appropriate adaptor, to test both copper and fiber installations on the one instrument.
“Advances in fiber optic production methods mean that this form of cabling is fast becoming an affordable alternative to copper in many applications, and it is indeed becoming very popular within new VDV installations. With this increased popularity comes the added complication of installation, testing and certifying. This increase in popularity is also driving a new requirement for test equipment specifically for fiber installations,” Dennis said.
From basic optical time-domain reflectometers (OTDRs) to full-blown certification instruments, and everything in-between, the demands placed on test equipment manufacturers is at an all time high. This increases competition, keeps prices reasonable and provides installation and test companies with affordable solutions.
“Instruments have had to get faster, more compact, more reliable and affordable. Basically, the customer expects more for less. This is possible as new technology and improved manufacturing techniques allow the manufacturers to minimize production costs thus reducing list prices but, at the same time, introduce additional functionality,” Dennis said.
Dan Payerle, Ideal Industries’ networks test business unit manager, sees a significant demand for more complex VDV systems in residential installation, which drives the demand for more sophisticated testing.
“It used to be that a VDV system in a home consisted of coax for the televisions and twisted-pair cabling for telephone and data,” he said. “Today, many homes are prewired for CCTV and home automation systems that increases the amount of cabling in a home by multiple times. Smart homes often have [Internet-protocol]-enabled controls and sensors that require twisted-pair cabling throughout the home, often powered with [power over Ethernet], which requires another test for the installer to ensure proper operation.
“Testing the cabling is critical to ensuring the proper performance of every VDV system. Many rely on visual inspection alone believing that, if a termination looks OK, it probably is. There are two faults with this assumption: First, many connector types used in low-voltage communications cabling can be deceiving. Coaxial connectors, particularly BNCs used in CCTV applications are blind connections, meaning that the installer inserts the copper ‘stinger’ into a connector and doesn’t know for certain if it has made contact unless it is tested. Second, there is no way to tell what is going on inside the wall without proper testing. In commercial installation, pulling cable though metallic raceway and studs with burrs or missing grommets can cause shorts that would go undetected. In residential installation, drywall screws have ruined many a communications cable run when steel protection plates are not placed on the studs,” he said.
When testing installations of copper cabling, there are three classes of tester that can be used: verifiers, qualifiers and certifiers. When testing fiber optic installations there are three basic types of tests: visual, power loss and OTDR tracing, Payerle said.
“Having a single instrument that is capable of testing both copper and fiber optic cabling is very desirable,” he said. “It saves the cost of having two complete systems since, in many cases, the fiber optic testing capability is an optional module to the copper test system. Most qualifiers and all certifiers on the market today offer fiber optic testing ability. However, when shopping for qualifiers, make sure to check configuration options since some models are copper only while others are copper plus fiber. Many copper-only qualifiers cannot be upgraded to copper plus fiber. On the other hand, all certifiers can have the fiber optic option added at any time.”
One downside to having a single test system for copper and fiber is that it can be used on only one project at a time. Having dedicated test sets gives the installer the ability to test more than one project at a time.
“We also see the increased use of qualifiers in lieu of certification testing,” Payerle said. “Going back to the concept that sending actual data through a link is a valid way of testing, there could be a change in how designers envision testing their installations. Some may soon accept qualification as a substitute for certification.
“Commercial installations do not necessarily need to be certified. In fact, only about 20 to 25 percent of commercial installations in the U.S. are certified. It is usually limited to larger installations where a system warranty is offered by the cable/connectivity manufacturers.
“There has not been much change in certifiers over the last three years. Cat 6a drove the last significant increase in testing speeds in the U.S., up to 500 megahertz. However there are significant changes coming to the TIA, which will affect the U.S. The TIA is working on a specification for Category 8 to support 100 gigabits per second,” Payerle said.
Harley B. Lang III, RCDD, director of marketing, Fluke Networks, also weighed in on this topic.
“The network cabling landscape is evolving rapidly,” he said, adding that, “With cloud, virtualization, SaaS, BYOD, SANs, and other critical technologies quickly becoming the enterprise norm, it is more important than ever that the foundational layer cabling works as expected.
“However, the network landscape isn’t a clear, consistent sea of similar cabling projects, and the professional community is struggling to keep up with diverse demands.
“A recent Fluke Networks survey found that cabling professionals report 55 percent of cable they install is copper, 24 percent is fiber, and 8 percent is coaxial. Thirteen percent is wireless. Ninety-three percent of cabling professionals surveyed reported they expect the volume of cables they install every month to increase by 2014.
“This varied growth requires a high level of skill and expertise, and cabling contractor firms and organizations are struggling to keep up with qualified staffing demands. Seventy-seven percent of cabling managers believe they could get jobs done faster with more skilled employees, but 71 percent stated finding good temporary workers is a challenge. The struggle continues up the ladder to project managers, with more than half reporting they are stretched too thin,” Lang said.
Testing and certifying cable is directly correlated to timely payment for work completed. The sooner a contractor can gain systems acceptance from the customer, the faster payment can be received and labor hours devoted toward additional jobs. With the pure volume of jobs today, staffing difficulties and complex standards, reaching systems acceptance is more complicated and time consuming than ever, leaving cabling contractors at risk of losing money every step of the way, from setup to completion, according to Lang.
What do these trends mean for the industry? Today’s cabling testers need to be quick, agile, flexible, capable for a variety of mediums, and provide help with managing multiple simultaneous, varied projects, he said.
“Cable testers vary in capability, type of testing, and complexity from simple continuity or wiremap testing to advanced measurements and calculations. For basic testing, verification and qualification testers are an inexpensive solution but typically are only capable of testing a single media type and performing basic troubleshooting functions. For today’s enterprise cabling, more advanced testers are necessary to meet standards and certification requirements. In North America, testing and cabling should meet ANSI/TIA 568-C requirements, which ensures that testers are sufficiently accurate and appropriate for parameters and limits to which the cable is tested. Certification testers support these tough standards and provide the deepest diagnostic capabilities on the market.
“Many of these testers are modular, supporting twisted-pair, fiber loss, and even OTDR testing. Further, some testers take testing a step beyond simply ensuring speed of testing with user-friendly methods of selecting cable types and test limits built right into the tester and project management features for recalling and sharing job requirements and status,” Lang said.
Whatever cabling solution or technology is used, it’s good to know the tool manufacturers are developing new items to meet your needs.