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When it comes to cable installation, the "right" tools and testers can improve residential profitability.


January 1, 2006  


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Efficiency is vital in cable installation. Increasingly vast networks of wires and cables supply vital electric power and communication services, increasing demands on a contractor’s time.

As line installers and repairers fervently install new lines and repair existing ones, the desire to do so more quickly and economically has increased.

This certainly applies to residential installations. In addition to basic electrical, telephone and TV cable, today’s homes now require structured cabling for computer networks, security systems and advanced home entertainment.

In today’s competitive residential installation, there are new tools and testers emerging at a rapid rate to perform various tasks and make the installer more efficient.

Installation: Vital for efficient cable installations are timesaving and ergonomic tools for cutting, stripping and working with all types of wire and cable. The correct punchdown termination tool enables the installation of Cat 5(e) jacks six to eight times faster. Punchdown tools increase accuracy and reliability.

Fewer reworks are needed, which increases client confidence. A punchdown tool may also be safer, reducing the risk that you will punch into the palms of hands or through drywall.

There are three types used to terminate telecommunications cables: manual, impact and multi-wire. When any conductor is punched down, force is required to seat the conductor.

That power can be derived from one of two methods: by human power by which an installer will use his hand or arm to generate the force to seat the conductor using a non-impact tool, or by the use of an impact tool.

The basic impact tool has a spring-loaded head, which is compressed by the installer with very little force required.

Once the spring reaches full compression, it is automatically released and the force is transferred to the head of the impact tool, which then seats the conductor. Advanced multi-wire tools terminate all pairs with one squeeze, reducing hand fatigue.

Most impact tools can be fitted with a number of interchangeable blades, depending on the cabling system being used.

The advantages of an impact tool are speed, ease-of-use and consistency of termination. The tool will help you push each wire into the slot to make a permanent connection.

Advanced punchdown tools have a built-in blade that cuts off the excess wire after the wire is pushed onto the connector, others may require wire cutters. They also offer an easy-to-use handle and a built-in bed that helps hold the jack in place.

Other new features include replaceable blade head for use with multiple jack types and wall-friendly designs to accommodate close-to-wall installations.

To use an advanced punchdown tool, the installer must first determine the wiring scheme in place, strip the cable jacket, place the eight wires in their respective slots, and then insert the jack in the tool.

After the trigger is pulled completely, the wires will be seated and cut for a solid termination. The handle is then released and the jack is removed from the tool. After visually verifying the proper termination, standard dress and press procedures are followed.

The combination of faster, more reliable terminations and less rework can cut the cost of this portion of the installation job by as much as 80%.

Three stages for residential testing: After installation, the job must be tested and delivered to the customer. For residential installations, there are three stages to the testing process: visual inspection, verification and final test.

The visual inspection detects obvious problems such as checking for kinks and knots, and making sure the correct separations are kept from electrical wiring and other communications cabling, as interference is unfavorable with electronic systems.

Either during or after visual inspection, the installer should use a verification test tool to ensure the cables are connected correctly. Verification test tools are often the first line of defense for cable troubleshooting. These tools allow technicians to see if the cable is properly connected.

They perform basic continuity functions such as wiremap and toning and sometimes include additional features such as a Time Domain Reflectometer (TDR) for determining length to the end of a cable or to a trouble spot. They may also detect if a switch is connected to the cable under test or check coaxial connections.

Verification testing confirms that a cable meets established national or international standards of conductor configuration and passes basic continuity testing. Verification may be performed on two-conductor or multi-conductor twisted-air cabling.

If the wiring is faulty, an advanced verification tool’s wiremap will identify the problem and the faulty pair. Fluke Networks’ MicroScanner Pro’s TDR length function measure the full length of a cable, it pinpoints reversed or crossed pairs and also identifies split pairs. The tool displays individual pair lengths and whether the cable is connected to a hub.

Qualification

The length measurement is also useful for billing and inventory purposes. If a fault is detected, time is often wasted with visual inspection. An advanced verification tool’s toner function allows continuity verification and to trace a cable through walls, floors and ceiling.

The final step in testing a residential installation is to check the actual performance of the cable. Qualification is a test of the cable to make sure it can handle the type of network traffic that’s expected of it.

The TIA-570-B residential installation standard says: “Cable qualification tests the cabling to determine that certain network technologies (e.g., 100BASE-TX, Firewire) will perform on the cabling system.”

Advanced qualification tools that identify the network speed which the existing cabling can support, are much more powerful than verification tools.

They are designed to allow minimally trained operators to determine if existing cabling ‘works’, and if not, why not.

Qualification testers also help the cabling contractor protect his work. A qualification tool not only tests the performance of a cable, but records the results.

This allows the contractor to document the results, and can be invaluable if the cable is later damaged by another contactor. Documenting the condition of the installation can save a lot of shouting later on.

It must be noted that qualification testers in no way compete with or replace cable certification tools. A certification tool is far more expensive and runs a far more stringent battery of performance tests. Certification is often required to obtain a warranty from the cable manufacturer in commercial installations. For residential work, a qualification test is more appropriate.

By using the right combination of installation tools and test tools, an installer can perform his job faster, with greater accuracy and less rework, all backed by documentation that the job was performed to recognized standards. It makes the business more efficient, and more profitable.

Brad Masterson is product manager for Fluke Networks Canada and a member of the CNS Editorial Advisory Board. He can be reached at brad.masterson@fluke.com.