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When
in
doubt
about
separation
distances,
the
"Rule
of
Sixes"
can
be
used.
This
rule
requires
six
feet
of
separation
between
telephone
wiring
and
open
high-voltage
wiring,
lightning
grounding
wire
or
grounding
rods.
It
requires
six
inches
of
separation
from
all
other
high-voltage
wiring
unless
in
conduit.
To
add
a
second
phone
line
to
an
existing
installation,
use
the
second
pair
of
your
existing
phone
wiring.
In
North
America,
residential
phone
wiring
carries
2
wire
pairs
at
a
minimum.
You
must
ensure
the
integrity
of
this
second
pair
throughout
the
home.
It
must
be
connected
to
the
black
and
yellow
terminals
of
your
phone
jacks.
Keep
in
mind
that
twisted
pair
cables
are
required
by
standard
for
multi-line
residential
phone
wiring.
When
wiring
phone
jacks,
maintain
the
correlation
between
the
twisted
pairs
and
the
jack
terminals.
Twisted
pair
1
to
terminal
pair
1,
twisted
pair
2
to
terminal
pair
2
and
so
on.
At the completion of a new installation, test
everything and preferably use testing tools that are specifically
designed for telephone wiring components.
After
completing
a
new
phone
wiring
installation,
always
do
a
visual
inspection
of
your
color
matching
at
all
interconnects.
And
make
sure
your
polarity
is
OK
at
the
head
end
(demarcation)
point.
For
new
wiring
installations,
test
every
single
pair
of
the
whole
premise
telephone
wiring
for
continuity,
shorts
to
other
pairs,
shorts
to
ground
and
reverse
polarity
as
well.
Whether
you
are
performing
new
installations,
expanding
an
existing
installation
or
troubleshooting
equipment
malfunction,
sound
knowledge
of
telephone
wiring
testing
procedures
will
reduce
time
consumption
on
these
jobs.
Noise
on
a
phone
line
in
the
form
of
a
continuous
hum
is
generally
caused
by
a
grounded
wire.
To
test
for
shorts
to
ground:
- Find
a
good
ground
point.
For
instance,
the
screw
that
attaches
most
faceplates
at
electrical
outlets.
- Get
a
voltmeter
and
set
it
to
the
DC
voltage
range.
- Place
the
negative
lead
of
the
voltmeter
at
ground
and
the
positive
lead
at
the
wires
or
terminals
of
a
telephone
jack.
- If
it
reads
any
voltage
at
any
wire,
there
is
a
problem
with
the
pair
that
is
involved.
The
other
wire
of
that
pair
is
in
effect
grounded.
Another
way
to
test
for
shorts
to
ground
is
to
repeat
the
above
procedure
with
two
changes:
Disconnect
first
the
telco
line
at
the
demarcation
point.
Secondly,
use
the
Resistor
range
of
your
voltmeter
instead
of
the
Voltage
range.
This
is
a
test
for
continuity
between
ground
and
the
phone
wire.
Use
it
if
you
can
readily
disconnect
the
incoming
telco
line.
Any
telephone
wire
buried
within
concrete
will
develop
ground
problems
over
time
moreover
if
the
area
is
constantly
wet.
In
existing
installations,
one
symptom
of
a
grounded
wire
on
a
phone
line
is
when
your
incoming
calls
get
truncated
after
the
first
couple
of
rings.
When
a
complete
or
partial
segment
of
the
installation
does
not
deliver
the
dial
tone,
there
is
an
open
in
its
way
to
the
demarc
point.
A
test
for
continuity
of
the
involved
pair
will
resolve
the
problem.
Proceed
segment
by
segment.
To
test
for
continuity
of
a
twisted
pair
in
a
segment,
diconnect
one
end
of
the
pair
from
the
terminals
or
connectors
and
slightly
twist
them
around
one
another.
At
the
far
end
of
the
twisted
pair,
measure
continuity
with
a
Voltmeter
in
the
Resistor
range.
In
a
new
installation,
the
cause
of
discontinuity
is
likely
to
be
a
mismatched
wire.
In
an
existing
installation,
the
cause
might
be
a
defective
wire,
a
defective
connection
at
a
terminal.
Improperly
screwed
wire
at
phone
jack
terminals
may
cause
equipments
to
malfunction.
When
the
test
for
continuity
does
not
reveal
any
problem,
securing
the
connections
at
the
terminals
will
sometimes
resolve
the
problem.
Make
sure
the
metal
part
of
the
wire
under
the
screw
heads
are
clear
of
the
plastic
jacket.
Disconnect
the
incoming
telco
phone
line
at
the
head
end
(demarcation)
point
before
running
tests
for
shorts
and
reverse
polarity.
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Disclaimer:
This page reflects the best of our knowledge of structured wiring and holds no value other
than suggestions to potential users. It may change to offer suggestions that best fit
usage and new wiring methods. You are under no obligation to follow these
advice. Quantometrix, Inc. cannot be held liable
for any damage of any nature resulting from the use of the information published on this
page.
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Structured
Wiring
Tutorial
