Specifying cable

Q: I am under contract to a client that has very strict guidelines regarding specification of products; nothing specified can be product-specific. My client would like to have Category 6 cabling installed and verified. But I am not comfortable requiring that the cabling meet a level of performance that it is not yet defined. Do you have any suggestions? Given that no standard for Category 6 exists today, would you consider it reasonable to state that the cabling must meet the Anixter Levels Prog

Q: I am under contract to a client that has very strict guidelines regarding specification of products; nothing specified can be product-specific. My client would like to have Category 6 cabling installed and verified. But I am not comfortable requiring that the cabling meet a level of performance that it is not yet defined. Do you have any suggestions? Given that no standard for Category 6 exists today, would you consider it reasonable to state that the cabling must meet the Anixter Levels Program guidelines? I realize that the Anixter Levels Program is not an American National Standards Institute standard, but it is well-known and published and represents a definable target of performance.

Dagmar Nielson

Designer

South River, NJ

A: When a Telecommunications Industry Association (tia--Arlington, VA) committee ballots a document, the drafts are available to the general public for comment from Global Engineering Documents in Englewood, CO (tel: (303) 397-7956, www.global.ihs.com), for a fee. Category 6 is being developed in TR-42.7, but a project number has yet to be assigned for the work.

In the absence of a published standard, there are several options. Use the Anixter Levels Program, specify the SP number of the most current draft, or use these as resources to write your own specification. There are, of course, risks--the various drafts and actual standard may vary significantly.

I was forced to write my own specification for "Category 5" cable back when the 3+1 and 2+2 cable started appearing in the market. As tia`s Category 5 matured and changed, so did mine. Today, my specification looks very similar to what will eventually be published as Enhanced Category 5 (5E). But this is not without consequences. When we purchase cable, the entire specification, including a list of approved cables, must be attached to the request for quote.

When I first started doing this at the University of Texas at Austin, many distributors would see "4-pair, 100-ohm, 100-megahertz cable" and did not read "per attached specification." Since we are a state agency and buy low bid, they wanted to bid the least expensive, and usually the least performing, Category 5 cable. We would have them fax us the product data sheets and go through them line by line on the telephone until the salesperson understood why this particular cable was not on our list of approved cables. The reaction was usually the same: "You want a Category 5E cable." Our response was: "No, just a cable that meets our spec."

Then the manufacturer`s representative would call and usually say something like: "Our cable meets your spec, but the numbers we publish on our product data sheets are very conservative. You understand." To which we would respond: "OK, so have the product engineer sign and stamp a letter to that effect for our file." We have only one such letter in our file. This particular manufacturer produces both Category 5 and Category 5E with the only difference being the stamp on the jacket--and the price.

My point is that whatever you write into your specification is yours. If you want to use the Anixter guidelines, then that is your specification. There is a big difference between requiring a product to meet a certain list of requirements and requiring a manufacturer to have the distributor test and approve that product.

From a manufacturer`s perspective there is a big difference between producing a product that you can prove meets a certain list of requirements and being required to have the distributor test and approve that product. But there is no reason why a vendor-neutral buyer could not choose to use the same list of requirements as the distributor, or include a reference to the list, without requiring that the product undergo the distributor`s testing and approval.

For the curious: No, I did not use the Anixter program as a basis for my specification. I started writing before the company published its Levels 6 and 7.

Donna Ballast is a communications analyst at the University of Texas at Austin and a bicsi reg-istered communications distribution designer (rcdd). Questions can be sent to her at Cabling

Installation & Maintenance or at PO Drawer 7580, the University of Texas, Austin, TX 78713; tel: (512) 471-0112, fax: (512) 471-8883, e-mail: ballast@utexas.edu.

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