Information Technology Reference
In-Depth Information
install standard horizontal runs is difficult, even if the cable has been prepulled to the
expected area of the power/communications riser (commonly called the power pole)
of the module. If prepulled, enough wire must be left coiled in the ceiling to run down
later through the pole and through the wire pathways to an outlet/connector. This
leads to wasted wire, in the best case, and insufficient wire in the worst case.
In addition to the wire-pulling problems, the installer has the delightful task of
crawling down on the floor and under the modular desk, with flashlight and tools,
to terminate the horizontal cable at an outlet. After all this is done, the installer can
finally use a cable scanner to see if the link passes. Then, any problems that have
occurred must be solved at great time and expense.
The next significant cabling problem that occurs with the use of modular
offices, is that the modules can be easily rearranged. The furniture modules are very
easy to move about. The modules simply unbolt the same way they originally bolted
together, and then are moved as needed to reconfigure the office to meet new per-
sonnel requirements. In most of these modular furniture systems, the electrical con-
nections either snap together as the modules are joined, or they are easily cabled and
extended by a system of plugs and receptacles. Unfortunately, the communications
wiring, including our LAN wiring, must be painstakingly removed and rerouted into
the new furniture layout.
In many instances, the relatively delicate fiber and copper cables are the wrong
length in the new arrangement and cannot be reused. The only option in such a
home-run environment is to pull an entirely new cable to each relocated worksta-
tion. At an earlier time, this was the only approved method to run and rerun stan-
dards-compliant Category 5e and higher links, as the standard allowed no splices or
intermediate couplings.
2
However, a much better alternative is to run the horizontal cables to a series of
distribution points within an open area. Typically, these points of termination are
along the walls in the same area where electrical power will connect to a set of mod-
ular furniture. In some instances, the distribution point might be in a ceiling area
with the communications wires distributed to the furniture modules nearby. Then,
after the furniture is installed, cables can be extended from the distribution point to
the workstation outlets within the modules. This has now become an almost univer-
sal practice in open-office installations.
This method is not only much more practical, but also a good deal less expen-
sive, labor-wise, than dealing with home runs. Despite the standards to the contrary,
these links normally work fine and pass the applicable link tests. Early on, however,
2
A transition point is allowed; however, this is narrowly defined as a connection between the round
horizontal cable and flat undercarpet cable.
