Chapter
2
–
Installing
Modems
in
the
Rack
ZDX
Series
Modem
Racks
User’s
Guide
7
Tips
for
Mounting
Modems
in
the
Rack
If
the
chassis
is
installed
in
a
closed
or
multi
‐
rack
assembly,
the
operating
temperature
of
the
rack
environment
may
be
greater
than
the
ambient
temperature.
Be
sure
to
install
the
chassis
in
an
environment
that
is
compatible
with
the
maximum
rated
ambient
temperature.
See
Technical
specifications
in
Chapter
1.
When
mounting
the
equipment
in
the
rack
make
sure
mechanical
loading
is
even
to
avoid
a
hazardous
condition,
such
as
loading
heavy
equipment
in
the
rack
unevenly.
The
rack
should
safely
support
the
combined
weight
of
all
equipment
it
supports.
When
connecting
the
equipment
to
the
supply
circuit,
be
sure
to
check
equipment
nameplate
ratings
to
avoid
overloading
circuits.
Overloading
the
circuits
may
cause
damage
to
over
‐
current
protection
devices
and
supply
wiring.
Slots
and
openings
in
the
cabinet
help
provide
ventilation.
To
ensure
reliable
operation
of
the
product
and
to
protect
it
from
overheating,
maintain
a
minimum
of
1
inch
clearance
on
the
tops,
and
1
inch
clearance
on
the
sides.
Powering
Up
Once
power
is
applied
to
the
rack,
the
modems
perform
a
diagnostic
self
‐
test,
indicated
by
the
speed
LEDs
flashing
in
sequence
for
approximately
two
seconds,
then
the
19
or
28
(depending
on
model
of
ZDX
modem)
lights.
If
none
of
the
modems
have
power,
check
the
power
cord
connection
and
that
the
AC
outlet
is
live.
If
one
or
more
of
the
modems
do
not
power
up,
check
the
power
connection
to
that
modem.
If
one
of
the
green
power
supply
LEDs
on
the
front
of
the
rack
is
not
on,
then
one
of
the
redundant
power
supplies
is
defective.
Models
with
AC
power
inputs
are
intended
to
be
used
with
a
three
‐
wire
grounding
type
plug—a
plug
that
has
a
grounding
pin.
Equipment
grounding
is
to
ensure
safe
operation.
Do
not
defeat
the
grounding
means
and
verify
device
is
reliably
grounded
when
mounted
within
a
rack.
