Patrick McLaughlin
Recent testing by Underwriters Laboratories Inc. (UL--Melville, NY) has confirmed that the dsp line of products manufactured by Fluke Corp. (Everett, WA) performs tests of Category 5 local area networks (lans) with Level II accuracy in both the channel and the basic link. In announcing the test results, Fluke states it is the only organization to receive UL certification verifying Level II accuracy on channel tests.
To meet Level II accuracy, as it is defined by the Telecommunications Industry Association (tia--Arlington, VA) in its telecommunications systems bulletin tsb-67, cable testers must achieve near-end crosstalk performance of no more than 1771.6 decibels and attenuation performance of no more than 1771.0 dB. tia also defines the basic link and the channel in tsb-67. The basic link is commonly referred to as "horizontal cabling" and ends at the wallplate termination. The channel includes the cabling in the basic link, plus patch cords.
Fluke`s announcement states that, following random selection of dsp series cable testers from factory goods, UL performed full product evaluations as specified by tsb-67. UL recertified the dsp-100 CableMeter test tool and extended certification to the dsp-2000 Digital CableAnalyzer test tool, the company says.
According to Henriecus Koeman, principal engineer of the Fluke Networks Div., "Fluke likes to use UL--although it does not rule out the use of services of other independent testing organizations--because of UL`s strict interpretation of tsb-67, which states that the accuracy level shall be specified for both the basic link configuration and the channel configuration."
Koeman adds that most other field testers achieve Level II accuracy on the basic link but Level I accuracy on the channel. To achieve Level I accuracy, as defined in tsb-67, testers must achieve 1773.4-dB near-end crosstalk performance and 1771.3-dB attenuation performance.
Koeman says his company believes the certification is valuable to Fluke`s customers. "We find it to be an important service to our customers," he says. "UL follows a strict implementation of the standard requirements. UL also verifies what is claimed by manufacturers and clearly defines what can be claimed."
Koeman points out that as a means of preventing out-of-context statements, which may result in misleading claims, UL does not allow selective quoting from its reports. "This serves the end-user, not the manufacturer," he states.
"Fluke does not depend solely on UL for regulation and inspection of performance," Koeman concludes. "The Fluke Quality Assurance department also selects test samples at random intervals and runs the same tests UL performed."
Fluke`s dsp-100 cable tester lists for $4995, and the dsp-2000 lists for $5495. More information on the dsp series is available by calling (800) 44-fluke or visiting the Web site, www.fluke.com/nettools.
