Document 11478170

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OBJECTIVES
1. Describe various ANSI/TIA/EIA standards for commercial buildings
and residential settings.
2. Discuss the specific Technical Systems Bulletins that can affect
telecommunications installations.
3. Recognize and use standard grounding and bonding requirements for
telecommunications equipment.
4. Describe documentation methods that are used for cabling in a
commercial building.
The six major components of a structured wiring
system are:
The entrance facility—providing the point
where outside cabling interfaces with the
intrabuilding backbone cabling—the physical
requirements of the network interface being
defined in the ANSI/TIA/EIA 569 standard.
The main/intermediate crossconnect—located
in the equipment room and serving as the
interfacing between the entrance facility and
the backbone distribution system.
The six major components of a structured wiring
system are: (continued)
The backbone distribution system—provides the
interconnection between the telecommunication
closets, equipment rooms, and entrance facility,
and consists of the backbone cables, intermediate
and main crossconnects, mechanical
terminations, and the patch cords or jumpers
used for backbone-to-backbone crossconnections.
The horizontal crossconnect—provides the
interconnection between the work areas and the
telecommunications closets, typically on one floor
of a building.
The six major components of a structured wiring
system are: (continued)
The horizontal distribution system—extends
from the work area telecommunications outlet
to the telecommunications closet, and consists
of the horizontal cabling, telecommunications
outlet, cable terminations, and all related
crossconnections.
The work area(s)—components that extend
from the telecommunications outlet to the
station equipment, using wiring that is simple
to interconnect, move, and change.
The ANSI/TIA/EIA 569 standard addresses the
following elements of building pathways and
spaces:
Backbone Pathways—consist of intrabuilding
(within a building) and interbuilding (between
buildings) pathways, and may be either vertically
or horizontally oriented.
Intrabuilding Pathways—provide the means for placing
backbone cables from the entrance facilities or space, to
telecommunications closets, and from equipment rooms, to
either the entrance facilities or space, or telecommunications
closets. They consist of conduit, sleeves or slots, and trays.
Interbuilding Pathways—interconnect separate buildings, such
as those in campus environments, consisting of underground,
buried, aerial, or tunnel pathways.
The ANSI/TIA/EIA 569 standard addresses the
following elements of building pathways and
spaces: (continued)
Entrance Facility—consists of the telecommunications service entrance to the building,
including the entrance point through the wall,
and continuing to the entrance room or space,
and may contain the backbone pathways that
link to other buildings in campus environments.
Separation of telecommunication circuits from
power circuits and other electro-magnetic
energy sources is currently being studied by the
standards committees of the ANSI/TIA/EIA.
The ANSI/TIA/EIA 569 standard addresses the
following elements of building pathways and
spaces: (continued)
Equipment Room—centralized space for telecommunications equipment, which should house only
equipment directly related to the telecommunications
system and its environmental support systems.
Sizing—must meet the known requirements of specific equipment.
If equipment requirements are unknown, plan for 0.75 square feet
(0.07 square meters) of equipment room space for every 100 square
feet (10 square meters) of workstation space. Regardless of
equipment used, there must be a minimum of 150 square feet
(14 square meters).
Special-use building sizing—must base ER size on the number of
workstations.
The ANSI/TIA/EIA 569 standard addresses the
following elements of building pathways and
spaces: (continued)
Horizontal Pathways—should provide the facilities
for the installation of telecom-munications cable
from the telecommunications closet, to the work
area telecommunications outlet. Design guidelines
and procedures are specified for underfloor,
access-floor, conduit, tray and wireway, ceiling,
and perimeter facilities.
The ANSI/TIA/EIA 569 standard addresses the
following elements of building pathways and
spaces: (continued)
Telecommunications Closet—must be dedicated to
telecommunications functions and support
facilities only, with a minimum of one closet per
floor. Additional closets should be provided for
each area up to 10,000 square feet (1,000 square
meters) when either the floor area served exceeds
10,000 square feet (1,000 square meters), or the
horizontal distance exceeds 300 feet (90 meters).
The ANSI/TIA/EIA 569 standard addresses the
following elements of building pathways and
spaces: (continued)
Workstation—primarily concerned with the
telecommunications outlets, because they are the
usual connection point between the horizontal
cable and the connecting devices in the work area.
The reference is made to the overall box or face
plate as opposed to individual outlets/connectors,
with a minimum of one outlet face plate per
workstation required. The typical workstation
space allocation is one every 100 square feet
(10 square meters).
ANSI/TIA/EIA 569 provides recommendations
for the physical spaces and pathways used by
modern telecommunications cabling systems
and equipment, with recommendations made in
the following areas:
Telecommunications spaces, including work
areas, telecommunications closets, equipment
rooms, and entrance facilities. Specifications
provided include:
The sizing of telecommunications spaces
Floor loading requirements—dynamic and static
Environmental considerations—floor coverings, lighting
requirements, and so on
ANSI/TIA/EIA 569 provides recommendations
for the physical spaces and pathways used by
modern telecommunications cabling systems
and equipment, with recommendations made in
the following areas: (continued)
Telecommunications pathways, including horizontal
and backbone cable distribution systems—conduits,
sleeves, trays, and so on, and grounding pathways.
Specifications provided include:
The number of cable pathways to install
Acceptable types of pathways
Installation procedures
The ANSI/TIA/EIA 606 standard recommends
documenting the cabling system in the following
way:
Assign a unique identifier to each element of
the cabling system.
Create a document for each of the identified
elements.
Link related records to each other.
ANSI/TIA/EIA 607 specifies the requirements
for:
A ground reference for telecommunications
systems within the telecommunications entrance
facility, the telecommunications closet, and
equipment room.
Bonding and connecting pathways, cable shields,
conductors, and hardware at telecommunications
closets, equipment rooms, and entrance facilities.
Interconnectivity to other building grounding
systems.
Specifications for STP-A telecommunications
cable include:
Color-coding pair 1 as Red/Green, and pair 2 as
Orange/Black
Shielded, 150-ohm, 2-pair cable using 22 AWG
(0.63 mm) solid conductors
Should be marked as “150 ohm STP-A”, in addition
to any markings required by local or national safety
codes
Same mechanical and transmission requirements to
be applied to backbone and horizontal cables, with
additional requirements provided for outdoor runs
Specifications for STP-A connectors include:
Standard outlet interface and pair assignments
are similar to the ISO 8802-5 Token-Ring
connector (IEC 807-8), except that performance
requirements are more severe.
Marked as “STP-A”, with other markings
required by local or national safety codes
Specifications for STP-A patch cables include:
Stranded conductors at 26 AWG (0.4 mm)
Allows for an overall shield, rather than
individually shielded pairs
Less severe attenuation and NEXT loss
requirements than horizontal cable
Specifications for STP-A installation practices
include:
Shields should be grounded at the
telecommunication grounding busbar.
Shield voltage to ground should not
exceed 1 Vrms at the work area.
Shield resistance to ground should not
exceed 3.5 ohms at the work area.
Fiber is recommended for runs between
buildings at different ground potentials.
Table 7-1: TIA/EIA and ISO/IEC Standards Specifications
Table 7-1: TIA/EIA and ISO/IEC Standards Specifications
(continued)
Figure 7-1: Reconfigurable Panel
Figure 7-2: Using a MUTOA
Figure 7-3:
Using a
MUTOA to
Reconfigure
a Work Area
Figure 7-4: Using a CP
Some important requirements of CPs are:
Consolidation points shall not be located in
any obstructed area.
Consolidation points shall be located in fully
accessible, permanent locations such as
building columns and permanent walls.
Consolidation points shall not be installed in
furniture unless that unit of furniture is
permanently secured to the building structure.
Some important requirements of CPs are:
(continued)
Consolidation-point accessibility and marking
should follow the ANSI/TIA/EIA T568A
recommendation that a consolidation point
should be readily accessible and its location
visibly marked, for ease of routine
maintenance and reconfiguration.
Figure 7-5:
Using a CP to
Reconfigure
a Work Area
Consider the following as legitimate open office
locations for a CP or a MUTOA:
Utility columns attached to furniture
panels
Overhead storage cabinets
Enclosures at floor level
Freestanding utility columns
The National Electric Code (NEC) Article 800,
called Communications Circuits, covers the
installation of the following communications
equipment and circuits:
Telephone
Telegraph (except radio telegraph)
Outside wiring for fire alarms, burglar
alarms, and similar central station systems
Telephone systems not connected to a central
station system, but using similar types of
equipment
Table 7-2: NEC Substitution Chart
Table 7-3: NEC Wire Coding
Figure 7-6: Cable Substitution Hierarchy
REVIEW QUESTIONS
1 What is the purpose of the
ANSI/TIA/EIA T568A standard?
REVIEW QUESTIONS
2 Name the six items covered by the
ANSI/TIA/EIA standard.
REVIEW QUESTIONS
3 State the purpose of the ANSI/TIA/EIA
Telecommunications Pathways and
Spaces certification.
REVIEW QUESTIONS
4 What is the ANSI/TIA/EIA 570 standard
and how is it different from the T568A
standard?
REVIEW QUESTIONS
5 Name the three items that the ANSI/TIA/EIA
606 Administration Standards for the
Telecommunications Infrastructure of
Commercial Buildings standard recommends
for documentation of a telecommunications
cabling system in a commercial building.
REVIEW QUESTIONS
6 List five types of telecommunications
pathways.
REVIEW QUESTIONS
7 List four types of telecommunications
spaces.
REVIEW QUESTIONS
8 How did the FCC Part 68 decision affect
the telecommunications network in the
United States?
REVIEW QUESTIONS
9 Which bonding and grounding guidelines
take precedence in a given application,
ANSI/TIA/EIA standards or national/local
electrical code standards?
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