Chap 9 Structure Cabling Project

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Chap 9 Structure Cabling Project
Chap 9 Structure
Cabling Project
Andres, Wen-Yuan Liao
Department of Computer Science and Engineering
De Lin Institute of Technology
[email protected]
http://www.cse.dlit.edu.tw/~andres
RJ-45 jack
One side of the RJ-45 jack
contains eight color-coded slots
The other side of the jack is a
female plug, which looks like a
standard phone jack, except
that the RJ-45 jack is larger and
has eight pins
Surface-mounting an RJ-45 jack
Two types of boxes
Screw-mounted
box
Adhesive-backed box
Flush-mounting an RJ-45 jack
If you do choose to place the jack
on a wood baseboard, avoid
cutting the opening into the
bottom 5 cm of the baseboard
The wall's bottom plate will block
you from pushing it in
Safety Procedure
Any time you are working in
walls, ceilings, or attics, it is
extremely important that you
remember to turn off the
power to all circuits that go to,
or pass through, the work
area!
Procedure for placing the
copper wires into a jack
When you use RJ-45 jacks at the
telecommunications outlet in a
horizontal cabling scheme, the
wiring sequence is critical to ensure
the best possible network
performance
To punch down the wires into the
jack, you need to use a punch tool
Documenting cable runs
Whenever you install cable, it is
important that you document your
actions
A cut sheet is a rough diagram that
shows the locations of the cable
runs
 The
numbers of the classrooms,
offices, or other rooms, to which the
cables have been run
Types of labels
Label each cable connection at the
patch panel in the wiring closet
Place the connections so that the
labels are arranged in ascending
order
This allows easy diagnosis and
location of problems
Label the cables at each end
Preparing cable for routing
and labeling
Spools are usually packaged
in boxes
To help you keep track of
each cable as it comes off its
spool, assign a letter to each
spool
Easiest procedure for
routing cable
To wall mount cable you
need to select a device that
will secure it to a wall. One
such device is the tie-wrap
Mounting cable in raceway
Raceway is a wall-mounted
channel
decorative raceway - presents
a more finished appearance
 Enclose
cable on a wall inside a
room where it might otherwise
be visible
Gutter raceway - a less
attractive alternative to
decorative raceway
 Big
enough to hold several
cables
 Be restricted to spaces such
as attics and spaces created
by dropped ceilings
Running cable through
existing raceway
Can you think of any types of
cable that you would not
want to run next to CAT 5
UTP cable?
This would include any type
of power or electrical cable
Personal safety precautions
before installing cable
Whenever you work in walls,
ceilings, or attics, the first thing you
should do is turn off power to all
circuits that might pass through
those work areas!
Before you begin work, learn the
locations of all fire extinguishers in
the area
Wear appropriate clothing
Long
pants and sleeves
help protect your arms and
legs
Avoid wearing excessively
loose or baggy clothing
If it is catches on
something, you could be
injured
If you anticipate working in a dropped
ceiling area, survey the area. You can
do this by lifting a few of the ceiling tiles
and looking around
If you need to cut or saw, protect your
eyes with safety glasses
Consult the building's maintenance
engineer
Keep your work area orderly and neat
Building safety
Some building codes may prohibit
drilling or cutting holes in certain
areas such as fire walls or ceilings
If you find that you must route cable
through spaces where air is
circulated, you will need to use a
fire-rated cable
Wiring closet
A wiring closet serves as a
central junction point for the
wiring and wiring equipment
used to connect devices in a
local area network (LAN)
MDFs and IDFs
One wiring closet is designated
as the main distribution facility
(MDF)
All others, referred to as
intermediate distribution
facilities (IDFs)
Patch panel
A patch panel acts as a
switchboard, where horizontal
cables coming from
workstations, can connect to
other workstations to form a
LAN
Mounting a patch panel
The advantage of a
distribution rack is that it
allows easy access to
both the front and the
back of the equipment
Network operation testing
The baseline is a record of your network's
starting point or newly installed
performance capabilities
You should continue to test your network
You can do this by comparing current
measurements with recorded
measurements that were taken when the
system was known to be operating properly
Cable testers and distance
measurements
Cable testers, sometimes
referred to as time domain
reflectometers (TDRs),
measure the distance to
open-ended, or shorted,
cable
TDRs (time domain
reflectometers)
A TDR measures distance on a
cable by sending an electrical
signal through the cable
The signal is reflected when it
encounters the most distant
open connection
Split pairs
Visual inspection and crosstalk
measurements are the only
ways to detect a condition
known as split pairs.
When wires split, they are no
longer part of the same circuit
The signals are not protected
Signal attenuation
A cable tester can measure the
reduction in power of a signal
received from a device known
as a signal injector - attached to
the far end of a cable
Cable testers generally
measure attenuation at several
frequencies
Causes of NEXT
Twisted pairs that have become
untwisted
 After
being attached to crossconnect devices
 Cables that have been pulled too
tightly around sharp corners,
If you measure near-end crosstalk,
you should do a visual check of the
horizontal cabling
Summary
Structure cabling

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