 |
| Volume 3 Issue 1 February 1998 |
Features
Interviews
Reviews |
 |
| HTINews Article - Feb98 - [HTI Home Page] |
DIY Marketing Program Promote Your Products and Services [Click Message To Learn More] |
Low-Voltage
Wiring (Telephones)
|
Doug
Moses is a Regional Systems Development Manager for a large Securities firm with 10 years
of experience in the Computer industry with Networking and Programming. One of Dougs
hobbies is Home Automation. |
The telephone is one of the few low cost Home Automation devices that can
be installed in a home by the homeowner. Most states do not require a license to install
low-voltage wiring in homes (Low-voltage usually refers to less than 50 volts).
Although telephone wiring is commonly installed in existing homes, the best time to
install any wiring in a home is before the dry wall and insulation phase of home
construction. The wiring used for a home telephone systems can also be used by many Home
Automation devices. Some of these devices are: intercom systems, remote keypads for data
input, computer networks, and others. This article gives you the details involved in
wiring a home telephone system and shows you how you can incorporate it into your Home
Automation planning.
Telephone Jack Wiring
RJ45 is the standard used for computer networks. It is also used by many Home Automation
devices. RJ11 is the standard used for residential phones lines. RJ11 connectors are
smaller than RJ45 jacks and work when plugged into RJ45 jacks. Most RJ11 connectors have
only four wires. Most RJ45 connectors have eight wires. RJ11 usually only supports two
telephone lines. The most common used wiring standards are: T568A for RJ45 and 6x4 Quad
for RJ11. The following is a graphic display of both connectors and how they can be used
to work together.
Text Version
Telephone Wire Details
Telephone wire is usually 24 AWG (American Wire Gage) and comes in
twisted or untwisted pair. The more twists you have per inch the better. Telephone wire is
rated by Category 2-5. There is no Category 1 wire. Category 3 wire has fewer twists than
Category 5 wire per same distance of wire. The best wire to use for telephone connections
is Category 5 wire. The bare minimum number of wires needed for a residential telephone
system is two wires. Four pair Category 5 wire is the new standard used for networks and
telephone systems. Telephone wire is usually unshielded. The shielding of telephone wire
is not as important as the number of twists in the wire.
Connector Blocks
A 66 connector block is commonly used in commercial installations to
connect multiple telephone lines together. This type of block allows you to connect your
telephone lines together in a star configuration. Most residential installations do not
use a 66 connector block and are wired in series. A star wiring configuration allows you
to isolate bad telephone lines quickly and gives you a central location for all of your
wiring connections. The star method of wiring has become more popular over the years and
is more adaptable to future Home Automation projects. One common 66 connector block has 50
rows of connectors. Each row contains 4 connectors. A special tool called a punch down
tool is used to connect the wires together. The wire used is usually 24 AWG. Only some 66
connector blocks are rated for Category 5 wire. A 66 block uses jumper wires or cross
connectors to connect one open wire to another. Using one 4 pair wire as input you can
create up to twelve 4 pair output wires using this type of block. Only one wire can be
placed into one connector at a time. Cross Connectors are metal jumpers that slip over two
connectors and allow you to short two connectors that are next to each other. A Jumper
Wire can short any two connectors on any block. You can use both a Cross Connector and a
Jumper Wire on the same connector.
110 Connector Blocks are newer than 66 blocks and occupy less space than 66 connector
blocks. These blocks are more likely to be rated for Category 5 wire and often have RJ45
connectors already attached to them. A punch down tool is also needed for this type of
block but it uses a different blade than the older 66 block types.
Disclaimer This has been a quick fact packed article for telephone
wiring and is intended to be used as a reference guide and not a beginners tutorial. You
may need to read this article several times to fully understand all of the details that
are given. The information contained in this article is made in good faith and I make no
expressed guarantee that the information contained in this article is accurate.
