Installation manual

8-7
For more information call your Leviton representative or the Leviton Technical Hotline at 800-722-2082
© Copyright 2001 Leviton Manufacturing Co., Inc.
8
PRE-WIRE
Installation,
Labeling and
Documentation
Pre-Wire
Installation
In the past, the main low-voltage appliance in a home
was a telephone. The other was the doorbell. Known by
the acronym “POTS” or Plain Old Telephone Service,
this system worked well for what would now be viewed
as a basic, even unsophisticated single-line analog
phone service. POTS used quad wire, consisting of
four individual, non-twisted wires within a single cable
jacket and run in a daisy chain pattern. This meant that
a single wire served a long run of telephone jacks, if not
all of the jacks in a home. Damage to the line could
take all or many phones out of service.
Installer’s Tip: Quad wire is not an appropriate conduc-
tor for modern multi-line installations, and will result in
poorly performing telephone/modem/fax services, and
will not allow high speed data network communica-
tions. If you run across it during remodel work, replace
it with Category 5 or 5e structured cabling. Any quad
wire in a Category 5 or 5e 5 installation makes the
entire wiring system susceptible to noise. The NEC
has now made the use of Quad wire illegal.
Structured cable systems are not only more sophisti-
cated than quad wire, but they use a different routing
pattern as well.
8.4.1 Cable Topology
The daisy chain wiring pattern has been replaced with
the star pattern, also known as the home run. With the
star wiring method:
• Each device is wired directly to a distribution center
(the SMC)
• Service affecting problems are isolated to a single
cable and thus a single device
• Troubleshooting and repair are easier because the
damage can be isolated
TIA/EIA-570-A calls for star topology in residential and
light commercial cabling systems.
Cable from the SMC
Be consistant in your cable routing at the SMC.
Using the knockouts at the top of the SMC, keep
camera, telephone, data, and IR cable (Category 5
or 5e) to the left. Keep speaker wire separated. The
right side is for video cables (RG-6 quad shield).
Note that additional runs of Category 5 or 5e cable may
be needed for Home Monitoring, Multi-Room Video,
and other applications. These cable runs are above
and beyond the minimum cabling for the Essential and
Enhanced infrastructures.
Warning: Grounding and bonding systems are an integral
part of low-voltage cabling. Improper grounding and bond-
ing can induce voltages that disrupt telecommunications
circuits. Grounding and bonding must conform to all local
codes and conform to TIA-607 requirements for telecom-
munications infrastructure. Manufacturers’ instructions
should also be followed.
Conduit for Future Installations
Structured wiring will be a part of every new home at
some point in the near future. More and more uses and
devices will fuel customer demand. The system you
install today might need enhancing and upgrading
later on. For these reasons, Leviton and many contrac-
tors recommend the installation of empty conduit dur-
ing the framing stage so that it will be available for
future cabling. One of the best choices, and easiest to
install, is ENT flexible conduit in either 1-inch or 1 1/2-
inch sizes. It should be routed from the SMC:
• to the crawlspace or unfinished basement (if any)
• to the attic
• to the service entrance point (for telephone and cable
service
Be sure to install a pull string inside each run of conduit
to assist in future cable installations.
8.4.2 Cable Routing, Dressing, and Strain Relief
Category 5 or 5e cable is manufactured to deliver high-
speed performance to multiple end points. Category 5
or 5e cable does its job best when it’s handled appro-
priately. It is not a forgiving material medium that can
be pulled, stretched, and stapled the same way as
standard romex. A light touch on the installer’s part
goes a long way towards guaranteeing system integri-
ty and performance.
NETWORK
INTERFACE DEVICE
DEVICE
DEVICE DEVICE DEVICE DEVICE DEVICE DEVICE
DEVICE
COMMON
CONNECTING POINT
4
TWISTED PAIR
ROOM ROOM
(TELEPHONE WIRING DEVICE)
PVC OUTER JACKET
4 TWISTED PAIRS
TIA/EIA Preferred Wiring Method
The wiring method preferred by the Telecommunication Industry Association (TIA) is a star
wiring method (see Figure below). Each individual workstation in a residential or commercial
building is wired directly to the distribution device with four-pair twisted wire.
STAR TOPOLOGY