Sights, sounds guide do-it-yourself cable fault-finders

A building design team recently hired a cabling contractor to install in new corporate headquarters what it calculated to be 68,000 ft of telecommunications cable

Aug 1st, 2000
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tools

Steve Smith

Handheld cousins to more complex testers offer essential info at less cost.

A building design team recently hired a cabling contractor to install in new corporate headquarters what it calculated to be 68,000 ft of telecommunications cable. Fortunately, the contractor didn't take the design team's calculation for granted because what looked like enough cable on the spools to do the job turned out to be several thousand feet short. Through the use of a simple, handheld fault-finder, the contractor was able to measure the cable length ahead of time and could determine opens or shorts that would hinder installation.

As an easy-to-use inventory and testing tool, today's portable fault-finders are giving installers the basic, essential information they need without the expense, manpower, and complexity of full-sized versions.

"They can accurately measure length of copper [or fiber] on a spool, eliminating length issues ahead of time," explains Patrick Gould, product marketing manager for Jovial Test Equipment Inc. (Oakland, CA). "That way, you're not wasting tens of thousands of dollars of inventory."

One end is enough

Whether solving problems in inventory assessment or for actual cable damage, Jovial's ShortStop fault-finder, priced at $349, is one of several recent tools designed for the one-armed-paper-hanger installer. It can accurately measure the distance to an open or short from just one end of any two (or more) conductor cables up to 2,500 ft, with an error rate of ±3%. Size, gauge, and temperature variables are automatically adjusted, turning a two-hour job into one that takes minutes.

The handheld time-domain reflectometer, Gould says, reports the first failure that it finds. For example, if you connect the tool to a spool of cable that you're sure contains 200 or more feet, and you get a reading of 40, then you have a short or open at 40 ft.


Datacom Textron's newly introduced Ra line of cable-testing solutions includes the MicrOTDR Optical Fault Locator (upper left), which lets you determine the location of problem areas, the FiberLive Light Detector (upper right) for troubleshooting active/inactive fiber, and the FiberProbe Visible Fault Locator, which provides instant location of damage.
Click here to enlarge image

In addition to its fault-finding, the ShortStop's PowerTone multimelody system can verify the pair you're connected to is the pair you need. "During an installation, you can wind up with multiple pairs at the far end of your job, and you can't quickly tell which pair is connected at the other end," Gould explains. "The [ShortStop's] tone characteristic will change when the cable is momentarily shorted so you know if you're connecting to the right set."

In July, Jovial introduced a companion product for the ShortStop, the Scout Tone Receiver ($59), which can trace a tone as far as 6 inches from a given cable. It's designed to pick up the ShortStop's tone injected onto a wire pair, resulting in even faster trouble identification. The Scout offers volume control, headset jack, and a recessed "on" switch.

Also using sound to signify cable faults, Harris Corp. (Camarillo, CA) introduced its TS100 Cable Fault Finder ($359 list) at SUPERCOMM 2000 in June. When installers clip onto an unidentified pair at a job site with voltage up to 250 V, the TS100 will immediately sound an alarm.

The device features a tone generator that identifies a specific pair quickly, even in proximity to current-bearing cable. And like the ShortStop, the TS100 is designed for one-person operation, works on two- (or more) conductor cable up to 2,500 ft, and requires no additional calibration for wire thickness. Its simple menu is designed for easy reading even in poorly lit environments.

Let there be light

While the TS100 and ShortStop are among the latest breed of fault-finder tools to rely on audio technology to help pinpoint trouble, Datacom Textron (Everett, WA) has used optical sources as guiding lights in their new Ra series of testing solutions—named for the ancient Egyptian sun god.

The MicrOTDR Optical Fault Locator, introduced earlier this summer, uses optical time-domain reflectometer (OTDR) technology to make accurate measurements of fiber-optic cabling lengths up to 20 km and help installers pinpoint the location of optical reflective "events" caused by faults such as bad connections, splices, tight bends, and cable damage.


The ShortStop cable fault-finder from Jovial Test Equipment lets a single installer locate opens and shorts in any two- (or more) conductor cable.
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Billed as a low-cost alternative—$2,895 list—to more-complex mini-OTDRs costing about $10,000, the MicrOTDR does for multimode and singlemode fiber what the ShortStop, TS100, and others do for twisted-pair. Since purchasing and installing large quantities of fiber is a considerable investment, says Datacom Textron senior product marketing manager Lisa Schwartz, the MicrOTDR lets you measure for faults on the reel before you attempt an installation. "It displays up to seven different events, with the distances of those events measured in feet or meters," says Schwartz. "Compared to the display offered by more complex OTDRs, the MicrOTDR is a low-cost entry-level competitor: It's just that your key fault-finding results are in text instead of graphical [representation]."

For installations where you need an instant fault determination and can deal with the details later, Datacom Textron's new FiberProbe Visible Fault Locator, which costs $595, can detect breaks with an ultra-bright visible laser. The pocket-sized, waterproof tool looks like a flashlight and has a quick-connection feature that lets you attach to ST, SC, FC, and other common connectors without needing special adapters.

There are no hidden tricks with FiberProbe: What you see is what you get. "You plug it into your cable, and if there's a break, the cable will glow," says Schwartz.

For troubleshooting for active or inactive fiber, the Ra line also includes the simple FiberLive Light Detector, priced at $249, which you can insert directly into the sheathing to detect problems. It works with all fiber connector types and can detect singlemode wavelengths through a loop of the fiber.


Harris Corp.'s TS100 features a tone generator that helps installers identify a specific pair quickly, even when in proximity to current-bearing cable.
Click here to enlarge image

Want both audio and visual fault-finding? Paladin Tools' (Ashland, VA) newest handheld tester, LAN ProNavigator, finds cable faults for both coaxial and data cables and traces wires via tone and remote lights. The palm-sized, two-piece tester lists for $119 and includes a main unit and remote, which show test results at both ends of the cable.

LAN ProNavigator detects opens, shorts, crossed wires, and split pairs and features one-button (pass/fail or fault-find) testing. Using a 9-V battery, this audio/visual fault-finder is especially designed for testing shielded or unshielded Category 5 and Category 6 cable.

Whether you prefer to detect your cable trouble spots audibly or visually, Jovial's Gould offers the bottom line on portable fault-finders: "For quick troubleshooting, they're a must for every installer to have in his toolbelt."


Second Annual Salary Survey

Cabling Installation & Maintenance is conducting its second annual salary survey of the telecommunications industry. To participate, fill out the form on our Website (www.cable-install.com)—and pass the word. The more people who participate, the better information we can provide you.

We will publish the survey results in Cabling Installation & Maintenance later this year.

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