Installation manual

continued from page 7-1
For more information call your Leviton representative or the Leviton Technical Hotline at 800-722-2082
© Copyright 2001 Leviton Manufacturing Co., Inc.
7-8
7
SYSTEM
DESIGN
System Design
and Placement-
Laying Out the
Basics
The primary difference among the SMCs is their size: the
larger the box, the more modules and panels it can hold.
In addition, (the 280 and 420 series each have a surge-
protected AC power option to accommodate multiple
active modules). There is virtually no limit to the size or
complexity of the system you install in a normal resi-
dence. Every room can be wired for data, telephone,
and multi-media. Unlike AC wiring, where you must
meet, for instance, mandatory spacing requirements for
devices and minimum installation standards, residential
structured cable standards are more versatile.
✍
Take Note: The key to structured wiring is to have a sin-
gle distribution center as the point of origin for your cables
rather than a series of stand alone modules. Make sure all
modules are installed in a Structured Media Center.
Installer’s Tip: You can always install additional SMCs
should your client’s needs exceed the capacity of a
single unit.
7.3 Mud Ring Locations
Leviton strongly advocates the use of mud rings for
wiring wall plate locations if allowed by local codes.
Mud rings make it easier for you to maintain a service
loop, or extra cable, in the wall cavity without the pos-
sible damage or excessive bending to a cable that can
result from stuffing it into an electrical box. Their loca-
tions by room and within each will be determined by
your floor plan and by the end use device.
Installer’s Tip: You can use a standard electrical box if
you haven’t got a mud ring, but remove the back sec-
tion from it first. This will allow you to leave a service
loop in the wall while providing a mounting surface for
your device and cover plate.
7.3.1 Location Matrix by Type
Location will depend on the floor plan, but you can
assume the following:
• Install a mud ring for one phone and one data port
per room
• Allow for one audio/video device per room
• Allow for one analog volume control wall unit per
stereo speaker zone requiring a volume control.
• Every room with a security camera will require one
mud ring at the camera location
Installer’s Tip: Just as the NEC prohibits the installation
of AC electrical outlets above most baseboard heaters
(Section 110-3[b]) because of the potential damage to
any electrical cord plugged into that outlet, you will
want to avoid installing a low-voltage device above
these heaters for the same reason.
7.3.2. Number per Room
The TIA/EIA Residential Telecommunications Cabling
Standard suggests the following in regard to telecom-
munications cabling:
• A minimum of one outlet location (where applicable)
in the kitchen, each bedroom, the family or great
room, and the den or study
• Sufficient outlets in each of these rooms along any
unbroken wall spaces measuring twelve feet or more
in length
• Additional outlets as needed so that “no point along
the floor line in any wall space is more than twenty-
five feet, measured horizontally, from an outlet loca-
tion in that same space”
7.3.3 Installation Height Above the Floor
It’s difficult to state any hard and fast rules regarding
the location of most mud rings. In a children’s play-
room, for instance, your client might want a wall phone
installed lower than the 48” standard height. The height
of a counter or backsplash, or the location of a sink for
that matter, will determine the placement of mud rings
in a kitchen. Using AC wiring as a guideline, you’re
safe installing your mud rings at the following heights
measuring from the floor to the bottom of the mud ring
opening:
• Wall phones: 48”
• Desk phones and fax, data ports, audio/video, and
floor-mounted speakers: 15” or the same height as to
the bottom of installed electrical outlet boxes”
• Wall-mounted speakers: vary by design and plan
• Volume control for speakers: same as to the bottom
of electric light switch boxes
• Wall-mounted security camera: varies by design and
plan
Installer’s Tip: As you’ll see in Section 8, be sure to run
your low-voltage wiring in a separate stud space from
the AC cable. Be sure your mud ring locations keep
this rule in mind.
Installation Manual