"It is the responsibility of installers and end-users to oppose installation requirements that they believe to be impractical in the field."
Dennis Mazaris
PerfectSiteInc.
Before an installation requirement can be proposed and accepted as part of a standard in the cabling industry, field performance must be thoroughly examined to determine the needs of installers and end-users. This dictum should be applied not only to the demands of initial installation but also to the entire life cycle of the structured cabling system. An installation requirement must also be practical, with analysts in the field determining that it can be achieved with reasonable effort and at reasonable cost. And finally, of course, it is essential that any product or procedure that is part of the installation requirement be thoroughly tested, not only in the laboratory but also at the jobsite.
I have been forced to think about these things because of a product I developed recently: the PerfectPatch. Using reverse engineering, I first studied the way in which the cabling industry typically does patching. Based on this research, I invented and extensively tested a product that lets the installer easily adjust unshielded twisted-pair (utp) and fiber-optic patch cords to length--slack in patch cords being the major contributor to the unsightly rat`s-nest appearance often found in telecommunications closets. The product is Category 5-compliant for both performance and bend radius, meeting the specifications of the tia/eia-568a and iso/iec 11801 standards.
Many times, installation requirements are crafted to support the cabling industry`s need to accommodate ever-faster transmission speeds. In such cases, cabling installers and cable-plant managers may be obliged to install structured cabling systems complying with installation requirements that are inadequately researched and impractical in the field.
Myths about bend radius
Misconceptions and myths can also undermine the standards effort. Take, for example, the case of patch-cord bend radius. Industry "groupthink" dictates that you need large, sweeping bends in patch cables--four times the outer diameter of utp cable, for instance--in order to comply with the premises cabling standard.
But, surprise! There is no standard covering bend radius in patch cords. The reality is that it is impractical--almost impossible, in fact--to maintain a patch-cord bend radius that large in a system where changes are frequently made. This reality leads many users to ignore as impractical what they perceive to be the standard, a fact which could lead to the more serious problem of ignoring actual standards.
Having attended standards meetings of the Telecommunications Industry Association (Arlington, VA) and other organizations over the past few years, I realize that manufacturers run the show. Installers and end-users are not present in force at these committee meetings because of scheduling conflicts and the cost of attending. It would be possible, however--and it is time--for the manufacturers serving on these standards committees to go into the field and actively research and document the materials and procedures of the installation requirements they will be asked to ascertain. If that happens, I will not have to sit in the back of a committee room listening to people who do not pull cable for a living setting installation requirements that the cabling industry must follow for years to come.
I think that it is the responsibility of installers and end-users to oppose installation requirements that they believe to be impractical in the field. These two groups should be asking manufacturers and distributors to explain how and why requirements were adopted--and they should not be shocked by the answers they get (or, in some cases, the lack of answers). Questions and inquiries from those working in the field will prompt more thorough research by the manufacturers to determine how tasks are performed.
Such interchanges can only improve future installation requirements, which must be the result of compromise between theory and practice. Theory says that faster and faster transmission speeds are achievable, but five years from now, when we are operating networks at multigigabit speeds, we must have realistic installation requirements that can be met in the field. q
Dennis Mazaris is the principal of PerfectSite Inc. (Sterling, VA), a consultancy serving the cabling industry, and the manufacturer of the PerfectPatch.