OBJECTIVES
1. Define horizontal cabling.
2. Describe backbone cabling.
3. List different types of backbone cable systems and describe their
attributes.
4. Describe a crossconnect panel.
5. Describe procedures associated with proper cable management.
Figure 5-1: Structured Cabling System
Figure 5-2: Horizontal Cabling System Components
Table 5-1: Wire Colors for TC Crossconnect
Figure 5-3: Horizontal Crossconnect
Figure 5-4: Horizontal Cable Run Distances
The types of cables that are recognized by TIA
for horizontal cabling are as follows:
4-pair, 100-ohm unshielded twisted-pair
(UTP) cables.
2-pair, 150-ohm shielded twisted-pair
(STP) cables.
2-fiber, 62.5/125-micron optical fiber cable.
Figure 5-5: Telecommunications Outlet Cabling
Choices
Figure 5-6: UTP Pair Assignments for 8-Position
Modular Jacks
LAB 13 OBJECTIVE
Installing a Punch-down Modular Outlet
To understand how to install
an RJ45 punch-down modular
outlet on a section of 100-ohm
UTP cable
TIP
The end of the cable needs to be prepared first.
Once you have done that, simply disregard the
instructions that pertain to connector or cable
types that are not included in your parts
inventory. Keep in mind that the unshielded
twisted pair cable does not require the grounding
clip to be installed. Use the stuffer cap for one
side of wires, and the punch-down tools for the
other side. Once the wires have been punched
down, go ahead and install the second stuffer cap
so that both halves of the jack look identical.
Figure 5-7: Testing Modular Jack and Cable
Continuity
TIP
Recall that the RJ45 cable from Lab
procedure 6 was already checked. Any
problems noted on this test should point
to the newly created cable.
Figure 5-8: Fitting the Outlet into the Wall Plate
TIP
Don’t worry about installing
the modular jack upside-down,
because the design of the wall
plate will prevent this.
LAB 13 QUESTIONS
1 What does the instruction sheet 408-3354
indicate about keeping the wires twisted
to within specific distances from the
termination?
LAB 13 QUESTIONS
2 When using the steel-tip
punch-down tool, what impact
setting is recommended?
LAB 13 QUESTIONS
3 Are the wires cut on the inside or
the outside of the wiring block?
LAB 13 QUESTIONS
4 How are dimensions indicated on
the instruction sheet?
LAB 14 OBJECTIVE
Assembling Edge-Connector Modular Outlets
To understand how to assemble
an RJ45 edge-connector modular
outlet on a section of 100-ohm
UTP cable
TIP
Although you will be using 100-ohm UTP
cable, this type of RJ45 modular outlet
can accommodate STP cable of both the
100-ohm, 8-wire and 150-ohm (Token
Ring), 4-wire systems. When installing
the connector within the matching
housing, your parts may either snap or
screw together.
Figure 5-9: Aligning the Connector and Housing
Figure 5-10: Removing 2 Inches of UTP Cable Jacket
TIP
A 110Connect arrangement comes with
the edge connector already installed in
the port housing and remains this way
during the wiring. The AMP-BARREL
arrangement requires that the edge
connector be terminated prior to its
being mounted into the housing. Both
types of installations are covered in the
instruction sheet.
TIP
Don’t forget to install the two stuffer
caps on the edge connector, regardless of
how the wires were punched down. They
help to protect the connections against
exposure.
Figure 5-11: Pushing the Jack Insert
TIP
As a rule, any housing that will not
currently carry an active service would
be outfitted with a blank insert, until a
future need for expansion occurs. You
will not be installing a face plate as part
of this lab procedure.
Figure 5-12: Testing Modular Jack and Cable
Continuity
LAB 14 QUESTIONS
1 After reading the instruction sheet 408-3232,
which edge connector (110Connect or AMPBARREL) appears to be the easiest to
install?
LAB 14 QUESTIONS
2 Which type of edge connector
(110Connect or AMP-BARREL)
requires termination prior to being
installed in the housing?
LAB 14 QUESTIONS
3 Why is it a good idea to lace the middle
wires into the edge connector first?
LAB 14 QUESTIONS
4 Which type of edge connector comes
already installed in the port housing?
Figure 5-13: Work Area Components
The important specifications related to work area
cabling include:
Equipment cords should have the same performance
capabilities as patch cords of the same type and
category.
When adapters are used, they should be compatible
with the transmission capabilities of the equipment
to which they connect.
Maximum horizontal cable lengths are specified
using a maximum cable length of 3 meters (9.8 feet)
for work area equipment cords.
The important points to remember about
horizontal cabling subsystems include:
Any application-specific components (such as
splitters or baluns) cannot be installed as part
of the horizontal cabling system. If used, they
are located external to the telecommunications
outlet or horizontal crossconnect.
The proximity of horizontal cabling to sources
of EMI must be taken into account.
The important points to remember about
horizontal cabling subsystems include:
(continued)
Horizontal cable types that have been recognized
by TIA/EIA T568A include:
4-pair, 100-ohm UTP
2-pair, 150-ohm STP-A
2-fiber (duplex), 62.5/125 µm, or a multimode
optical fiber such as 50/125 µm, which is
permitted under TIA/EIA T568B
The important points to remember about
horizontal cabling subsystems include:
(continued)
ISO/IEC 11801 permits 120-ohm UTP, and
50/125 µm multimode optical fiber.
Multipair and multiunit cables are permitted, as
long as they meet the hybrid/bundled cable
requirements of TIA/EIA T568A-3.
Grounding must conform to all applicable local/
federal building codes, as well as TIA/EIA 607.
The important points to remember about
horizontal cabling subsystems include:
(continued)
A minimum of two telecommunications outlets
are required for each individual work area,
such that:
The first outlet is wired to 100-ohm,
twisted-pair.
The second outlet is wired to 100-ohm,
twisted-pair, or to 150-ohm STP-A, or to
62.5/125 µm multimode fiber.
The important points to remember about
horizontal cabling subsystems include:
(continued)
One transition point (TP) is allowed between
different forms of the same cable type, such as
in situations where under-carpet cable connects
to round cable. This term is broader by
definition in ISO/IEC 11801 than in TIA/EIA
T568A. In addition to the transitions for undercarpet cabling, it also includes consolidation
point (CP) connections.
The important points to remember about
horizontal cabling subsystems include:
(continued)
Although 50-ohm coax is recognized by TIA/EIA
T568A, it is not recommended for new cabling
installations.
Although additional outlets may be provided, they
are considered to be in addition to, rather than
replacements for, the minimum requirements of
the standard.
For copper-based horizontal cabling, bridged taps
and splices are not permitted. Splices are allowed
for fiber, however.
Figure 5-14:
Backbone
Cabling System
Components
Figure 5-15: Telco Connector
Figure 5-16: Patch Panel with RJ45 Connectors
Figure 5-17: Cable Tidy Between RJ45 Panels
Figure 5-18: Patch Panel with ST Fiber Optic
Connectors
Figure 5-19:
Backbone
Cable Types
The types of cables that are recognized by TIA
for vertical backbone cabling are as follows:
4-pair, 100-ohm unshielded twisted-pair
(UTP) cables.
2-pair, 150-ohm shielded twisted-pair
(STP-A) cables.
2-fiber, 62.5/125-micron multi-mode optical
fiber cable.
1-fiber, 9/125-micron single-mode optical
fiber cable.
Figure 5-20:
Backbone
Configurations
The important points to remember about vertical
backbone cabling systems include:
Equipment connections to backbone cabling
should be made with cable lengths of 30 m
(98 feet) or less.
The backbone cabling shall be configured in a
star topology. Each horizontal crossconnect is
wired directly to a main crossconnect or to an
intermediate crossconnect, then to a main
crossconnect.
The important points to remember about vertical
backbone cabling systems include: (continued)
The backbone is limited to no more than two
hierarchical levels of crossconnects (main and
intermediate). No more than one crossconnect may
exist between a main and a horizontal crossconnect
and no more than three crossconnects may exist
between any two horizontal crossconnects.
A total maximum backbone distance of 90 m
(295 feet) is specified for high bandwidth capability
over copper. This distance is for uninterrupted
backbone runs. (No intermediate crossconnect).
The important points to remember about vertical
backbone cabling systems include: (continued)
The distance between the terminations located in
the entrance facility and the main crossconnect shall
be documented, and should be made available to the
service provider.
Multipair cable is allowed, provided that it satisfies
the power sum crosstalk requirements.
The proximity of copper-based backbone cabling to
sources of electromagnetic interference (EMI) shall
be taken into account.
Bridged taps are not allowed.
The important points to remember about vertical
backbone cabling systems include: (continued)
Recognized media may be used individually or in
combination, as required by the installation.
Quantity of pairs and fibers needed in individual
backbone runs depends on the area served.
Currently recognized backbone cables consist of:
100-ohm UTP cable
150-ohm STP-A cable
62.5/125 micron optical fiber cable
(recall that the TIA T568B specification
recognizes 50/125 µm multimode fiber)
single-mode optical fiber
The important points to remember about vertical
backbone cabling systems include: (continued)
Crossconnects for different cable types must be
located in the same facilities.
In ISO/IEC 11801, the equivalent cabling elements
to the main crossconnect (MC) and intermediate
crossconnect (IC) are called the campus distributor
(CD) and building distributor (BD), respectively.
Just as with horizontal cabling, two alternate
backbone cabling types are allowed by ISO/IEC
(120-ohm, twisted pair and 50/125 µm, multimode
optical fiber).
The important points to remember about vertical
backbone cabling systems include: (continued)
Again, 50-ohm coaxial cabling is recognized by
TIA/EIA T568A, but is not recommended for
new installations.
The following are the currently recognized
categories of UTP cabling by the TIA/EIA:
Category 3.
Category 4.
Category 5.
Table 5-2: Color Code for 100-Ohm UTP
The following is a list of recommendations for the
installation of 100-ohm UTP work area outlets:
All four pairs of a 4-pair cable should be terminated
on an 8-position jack.
All work area outlets should be terminated as either
T568A or T568B.
Both ends of a line should be terminated by the same
designation, either as TIA/EIA T568A or TIA/EIA
T568B.
The suggested maximum allowable untwisting for
CAT3 cable is 3 inches.
The following is a list of recommendations for the
installation of 100-ohm UTP work area outlets:
(continued)
TIA/EIA T568A specifies that the maximum
allowable untwisting of CAT4 cable is 1 inch, and
for CAT5 cable, the maximum allowable untwisting
is ½ inch.
It is suggested that the maximum allowable
untwisting for any category above CAT5 be less
than ½ inch.
Always leave 1 to 3 feet of service loop for repairs,
changes, moves, and additions.
The following is a list of recommendations for the
installation of 100-ohm UTP work area outlets:
(continued)
The bend radius should be no tighter than
four times the cable’s outside diameter
(usually 1 inch).
The bend radius for cables with more than
four cable pairs is ten times the cable’s
outside diameter.
The following is a list of specifications for
installing 100-ohm UTP cable:
Do not exceed 25 pounds of pulling tension on a
4-pair cable.
Do not cut, or damage, the cable’s outer sheath
when pulling it.
Follow the proper color code.
All of the hardware used should be of the IDC
type.
Installation must be neat and well organized.
The following is a list of specifications for
installing 100-ohm UTP cable: (continued)
Document every phase of the installation,
including the locations of all components.
Label cable runs at their beginning, middle,
and end for easy identification.
Figure 5-21:
CAT5 Patch
Cables
Cable design experts have zeroed in on several
chronic problems that have, as their primary
cause, bad patch cables being used somewhere
along the data path. These include:
Poor data quality through various
crossconnections
Communications networks bombarded with
increased error rates and junk traffic
Severe crosstalk and attenuation problems
Generally degraded network performance
Today’s manufacturers are striving to
differentiate their patch cable products through:
Quality testing
Various colors
Tolerance buffers
Icons
Strain-relief boots
Cost
Snagless features
User-friendliness
Quick turnaround
on orders
Manufacturers’
labels
Performance level
warranties
LAB 15 OBJECTIVE
Installing and Testing a DB15 Connector
To understand how to install a DB15
connector on transceiver cable for use
with 10base5 Thicknet systems
Figure 5-22: Tap/Transceiver Hybrid
Table 5-3: AUI Pin Assignments
Figure 5-23: Twisting the Foil Shield
TIP
If you are not wiring the shield to pin 8, strip
one inch of foil shield from each end of the
cable, without damaging any of the twistedpair wires inside the shield. Again, use the
tension scale/tape measure for accuracy. This
leaves 1/4 inch of foil shielding intact, and 1
inch of the twisted pairs (with bare drain
wire, where applicable) exposed at each end
of the cable.
Figure 5-24: Stripped STP Cable
Figure 5-25: Inserting a Wire into a Connector Pin
TIP
The edge of the crimper tool should line
up evenly with the edge of the barrel
portion of the pin.
Figure 5-26:
Lining Up
the Crimper
and Pin
TIP
If the wire is not tight, try rotating the
pin a quarter turn, and recrimp the
barrel.
Figure 5-27:
Orienting
the Tabs for
Crimping
Figure 5-28: DB15 Male Connector Pin Numbers
Table 5-4: DB15 Pin/Wire Assignments
Figure 5-29: Positioning the Insertion/Extraction Tool
Figure 5-30: Inserting a Pin with the Insertion/
Extraction Tool
Figure 5-31: Completed DB15 Male Connector Wiring
TIP
Figure 3-32 includes a wired foil
shield to pin 8.
TIP
The multimeter should show an infinite
resistance between any adjacent pins (or
wires) with the exception of pin 8 and the
foil shield, if applicable, and a short circuit
on matching continuity checks. If it does
not, the cable is not correctly prepared, and
you may have to repeat this procedure. If
the cable checks out good so far, continue
with the remaining steps.
Figure 5-32: Installing the Strain Relief
Figure 5-33: Positioning the Connector/Strain Relief
TIP
Make a preliminary check to be sure
that none of the wires are blocking the
screw holes.
TIP
You don’t want to tighten these
housing halves completely until
after the next few steps.
Figure 5-34:
Fastening the
Housing Halves
Together
TIP
Now it’s time to install the female
DB15 connector on the free end of
the cable.
Figure 5-35: Reading the Pin Numbers on a Female
DB15 Shell
Figure 5-36: Completed DB15 Female Connector
Wiring
TIP
Figure 3-37 includes a wired foil
shield to pin 8.
TIP
The multimeter should show an infinite
resistance between any adjacent pins (or
wires) with the exception of pin 8 and the
foil shield, if applicable, and a short circuit
on matching continuity checks. If it does not,
the cable is not correctly prepared, and you
may have to repeat this procedure.
Remember that the cable checked good
before you mounted the male hood. Any
problems should be confined to the newly
installed female connector shell.
TIP
Make a preliminary check to be sure
that none of the wires are blocking the
screw holes.
Figure 5-37: Fastening the Housing Halves Together
TIP
You don’t want to tighten these housing
halves completely until after the next
few steps.
TIP
To recover usable parts, clip the connectors
and store the remaining length of cable, and
disassemble the hoods, strain reliefs, and
end connector shells. Use the insertion/
extraction tool to remove any male/female
pins from the end connectors. Discard the
used pins and twisted-pair fragments and
recover all of the short screws, slide clips,
metal clips, retaining screws, connector
shells, housing hoods, and long screws.
LAB 15 QUESTIONS
1 Describe the differences in how pins are
numbered between male and female D
connectors.
LAB 15 QUESTIONS
2 Why should the continuity check
be done before installing the hood
housings?
LAB 15 QUESTIONS
3 When disassembling the D connectors,
which parts must be discarded?
Figure 5-38: IBM Token-Ring 150-Ohm STP Cable
Table 5-5: STP-A Balanced Mode Attenuation/NEXT
Signal Loss
The physical design of 150-ohm STP-A cable
should meet the following specifications:
The insulated conductor shall not exceed the
diameter of .26 mm (0.102 inches) maximum.
The cable shall be restricted to 2-pair only.
The color code for 150-ohm STP cable is as
follows:
Pair 1: green is tip, and red is ring.
Pair 2: black is tip, and orange is ring.
Two types of crossconnect panels are generally
used for STP patching:
A panel with IDCs for termination of
the building cables
An open panel with lock openings for
150-ohm, STP snap-type media
interface connectors
In either case, the installer needs to follow the
manufacturer’s recommendations for making
the terminations. Other recommendations
should include:
Allow 1 to 3 feet ( 1/3 to 1 meter) of service
loop for future adds, moves, and changes.
For 19-inch (483-mm) rack-mounted
crossconnect panel installations, allow room
on the rack for possible telecommunications
equipment associated with the 150-ohm STP
cable.
In either case, the installer needs to follow the
manufacturer’s recommendations for making
the terminations. Other recommendations
should include: (continued)
Racks should have at least the following
clearances for access and cable dressing
space:
30 inches (762 mm) in the rear
36 inches (915 mm) in the front
14 inches (356 mm) on the side
The following list summarizes the most important
recommendations for the installation of 150-ohm
STP cables:
Always follow the manufacturer’s recommended
termination methods.
Maintain at least 1 meter (approximately 3 feet)
of cable for a service loop.
Telecommunications closet design must follow
TIA/EIA 569.
Patch cord lengths should be limited to 7 meters
(approximately 23 feet).
Equipment cord lengths should be limited to 3
meters (approximately 10 feet).
To maintain proper cable management
techniques, you should:
Plan for those inevitable future changes by
allowing sufficient space in closets, and elsewhere,
to make them. Assure that all connections include
the necessary cabling service loops to effect these
changes, and to maintain category compliance.
To maintain proper cable management
techniques, you should: (continued)
Include the following items in your worksheet
documentation for each installation:
Indicate the length of cable runs to each room.
In order to save hours of future troubleshooting,
document all of your wiring and test results.
Also document any problems that may have
occurred, along with any solutions that were
found.
Include the following items in your worksheet
documentation for each installation: (continued)
Differentiate between all primary and
secondary outlet locations in your
documentation, and include the station phone
numbers for each access line.
Be sure to document the cabling color code, the
wire color combinations for each line, and the
relationships between the wire colors. This is
very important in situations where colors have
been converted at a distribution device.
Include the following items in your worksheet
documentation for each installation: (continued)
Maintain the relationship of pairs and lines at
the distribution device, and clearly label the
lines if the distribution device does not have a
valid marking scheme.
Note any special circumstances.
For future reference, remember to provide a
copy of the documentation at the wiring
location (near a distribution device) and to
keep a copy for your records.
To maintain proper cable management
techniques, you should: (continued)
Be certain that all your cable runs are labeled in
the middle, and at both ends, and clearly indicate
the marking scheme on your worksheet.
Logically plan the system crossconnect points so
that each individual channel can be tested without
making additional or unnecessary connections,
which would degrade system performance. This is
also an important point for category compliance.
To maintain proper cable management
techniques, you should: (continued)
Avoid making quick fixes to any installation.
Instead, use standard wiring practices to ensure
that all connections can be easily found and
identified, now and later. Crossconnections made
in ceilings, for example, are not standard, and
will probably be forgotten about and difficult to
manage.
To maintain proper cable management
techniques, you should: (continued)
Make your wiring plan consistent throughout your
documentation. Regardless of whether the
installation calls for a simple or complex wiring
plan, it must:
Be complete and orderly.
Be scrupulously maintained.
Be readily accessible.
Be decipherable by other installers.
To maintain proper cable management
techniques, you should: (continued)
Neatness is an essential ingredient of any
installation. Therefore:
All wiring should be laid out methodically
and consistently.
Closets should be kept clean, with adequate
room to work.
Unused equipment, leftover materials, and
miscellaneous items should be removed from
all ERs and TCs to provide full access to the
cabling and the equipment currently in use
at these locations.
REVIEW QUESTIONS
1 How much extra cabling should be
allowed for a service loop?
REVIEW QUESTIONS
2 What types of cables are recommended by
TIA to be used for vertical backbone cabling?
REVIEW QUESTIONS
3 Where should cabling be labeled?
REVIEW QUESTIONS
4 What is the maximum recommended
pulling tension on a 4-pair cable?
REVIEW QUESTIONS
5 What is the maximum cable length
from a user outlet to a station device?
REVIEW QUESTIONS
6 Hubs are connected together to the
crossconnect facilities using “riser”
or _____________.
REVIEW QUESTIONS
7 State the color code for an 150-ohm
STP cable.
REVIEW QUESTIONS
8 How much of a CAT3 cable can be
untwisted? CAT4? CAT5?
REVIEW QUESTIONS
9 What type of topology is horizontal
cabling?
REVIEW QUESTIONS
10 Define horizontal cabling.