Cool Tools: Residential Qualification Testing
Published: September 2009
With increasing sophistication of voice/data/video (VDV) systems installed today in private residences and multiunit dwellings, a growing number of installers, builders and their customers are recognizing the benefits of qualification testing.
Qualification testing of residential networks tests installations to TIA-570-B standards. It tests data transmission types that can traverse network cable and also may include troubleshooting suggestions if a cable cannot support specific speeds.
On the other hand, commercial installations must be certified to multiple TIA-568-B performance standards. They provide pass/fail re-sults in several performance categories, advanced diagnostics to troubleshoot failures, and document test results, which may satisfy war-ranty requirements of cabling manufacturers.
Verification tests basically identify connectivity and wiremap errors caused by incorrect termination of connectors.
For qualification testing, the prevailing standard—TIA-570-B—has been in place for a while, and fundamental testing technology for residential installations has not recently changed, said Subrata Mukherjee, Fluke Networks product manager for copper verification tools, portable network tools and handheld tools.
“What has changed,” he said, “are installers’ needs to keep up with the implementation of the existing technology and testing standards. What might have been purely theoretical a year or two ago is very real today. Contractors have the opportunity to expand their businesses through VDV installations. Following the residential installation standards, including testing with the proper equipment, will make a business profitable.”
Mukherjee said voice over Internet protocol (VoIP) phone service and VoIP phones are becoming common household fixtures.
“So is digital television transmission. Not just digital broadcasting but digital cable transmission and routing of digital TV signals throughout the home. Security systems now combine both wired and wireless components. None of [this technology] is new, but they are all things that an installer has to be able to handle.”
From a test tool perspective, Mukherjee said, this means having the right tools for testing a wider range of services. In some cases, that means looking for multifunction tools. In other cases, it may mean bundling the right combination of tools.
Qualification is a three-step process: a visual inspection, verification and qualification.
The visual inspection does not require equipment; it relies on the experience of the installer.
“Many options are available for verification tests,” Mukherjee said. “There are task-specific tools, such as simple wiremap testers and length detectors. A tone-and-probe set is recommended to identify cables in cramped distribution panels. A more useful verification test tool is one that combines five key verification functions in one compact package—wiremap, cable length, cable ID, distance to fault and tone generation. For all the testing power they provide, today’s verification tools are easy to use and priced such that every installer can, and should, have one.”
To complete a residential installation to meet the standard, a qualification or certification tester is required. (The terms “qualification” and “certification” are sometimes incorrectly interchanged.)
“Qualification testers are specifically designed to meet the needs of residential installers,” Mukherjee said. “At prices of qualifica-tion testers today, the purchase of a tool for final test is not only practical, it’s a good investment. Given the cost of a service call to repair an installation defect, a qualification tester can pay for itself in as few as five instances where problems were solved while on-site, and five truck rolls avoided.”
Dan Payerle, Ideal Industries datacom test business unit manager, points out that certification testers cost $5,000 or more, depend-ing on capabilities, while alternative, cost-effective, application-based qualification testers are available from $1,000 to $1,500. Where certification is not required or demanded by the customer, a cable qualifier is a cost-effective alternative to LAN certifiers and is useful for smaller commercial and residential installations because many building owners and tenants simply want to know that data can be passed throughout the building without problems.
Residential structured wiring includes a variety of wiring types that distribute signals through a home, including Cat 5e and above, coax RG-6 and RG-59, 14/2 or 14/4 speaker wires, and fiber optics. Cables often are bundled to simplify installation.
Certification testers for qualifying residential systems
Can certification testing equipment be used to qualify residential VDV cabling?
If installers perform both commercial and residential work, and already own certification testers for the commercial portion of the business, these tester can certainly be used for residential projects, answered Subrata Mukherjee, Fluke Networks product manager.
“However, certification testers are far more powerful tools than required for residential work, and frankly, it is too expensive for most residential installers,” he said. “Before the current residential standard was in place and qualification testers were available, most residential installers faced two choices: use a commercial-grade certification tester, or ‘wire and walk.’ While most installers recognized the potential downside of installing without testing, they could not justify the expense of a commercial certification tool. Qualification test tools have changed that.”
“The qualifier contractor,” Payerle said, “should be able to test various cable types including twisted-pair data, coax, telephone, security alarm and audio cables, as well as fiber. A simple ‘pass/fail’ test determines within seconds whether the installed cable can support applica-tions such as Ethernet or gigabit Ethernet. Bit error rate testing (BERT) is used for VoIP, data and video-over-IP applications. The qualifier’s TDR [time domain reflectometer] will measure cable length and identifies faults such as shorts, split pairs and opens.”
Among its testing products, Fluke Networks offers a kit that contains a qualification tester (CableIQ Residential Qualifier), a digi-tal probe (IntelliTone 200), documentation software (CableIQ Reporter), six cable identifiers, and various patchcords and couplers. The kit, Mukherjee said, allows installers to cover a wide range of test needs as efficiently as possible.
Payerle said a major trend in home VDV systems is fiber to the home (FTTH).
“According to research, 15 million homes now have access to fiber broadband, with 32 percent of them opting for fiber instead of ca-ble or DSL,” he said. “The number of North American fiber-to-the-home subscribers continues to grow at an annual pace of approxi-mately 1.5 million and now stands at more than 4.4 million. The future looks strong for FTTH. Its only competitor is the existing coax and copper loop combined with fiber to the DSLAM or cable head end. It will be exciting to see how much of the $7.2 billion allocated in the federal stimulus plan for broadband is spent on fiber, especially in the underserved and rural areas that the program targets.”
However, not all carriers that tout new fiber networks and high-speed Internet connections actually bring fiber to the home.
“We should note that fiber to the home is not the same as fiber in the home,” said Fluke Networks’ Mukherjee.
Some carriers were bringing FTTH to selected greenfield developments before the recession, but that likely has slowed. Most of AT&T’s new network is fiber to the node, with service to residences delivered by twisted copper. Only Verizon has brought true fiber connections to homes on a large-scale basis, but many small, rural communities are building FTTH systems to homes in their communities.
FTTH probably means more services and more data traffic throughout the home, Mukherjee said.
“This means a more extensive and more reliable home network,” he said. “The installation will become more complex and the need to test will increase. Service providers need bandwidth to bring a multitude of services to a large number of homes. Once inside the home, however, Cat 6 UTP is a more economical choice for final delivery of these services. The predominant residential cable types for VDV transmission remain coax and unshielded twisted-pair [UTP]. Cat 5e UTP is becoming less common, with Cat 6 UTP taking its place. To-day’s bandwidth requirements can be met by Cat 5e, but future-proofing a project by using Cat 6 is proving to be a compelling, and profit-able, selling point for installers.”
Qualifying residential VDV systems benefits all concerned.
By meeting industry standards, builder specifications, and component manufacturer requirements, returns to job sites will be re-duced, extended warranties can be offered and the ability to perform qualified installations sets the installer company apart from com-petitors who lack that capability, increasing future sales potential.
Builders benefit because customers value having a qualified VDV system that performs as expected. Manufacturers benefit because quality installations mean their products perform to expectations, enhancing the reputation of their components. Finally, homeowners benefit from trouble-free VDV systems that operate to full design potential.
GRIFFIN, a construction and tools writer from Oklahoma City, can be reached at firstname.lastname@example.org.