AC
power
recovery
After
normal
power
is
restored
after
a
total
AC
power
failure,
the
storage
subsystem
performs
power-up
recovery
procedures
automatically
without
operator
intervention.
Power
cords
and
receptacles
The
storage
subsystem
ships
with
two
jumper
cords
used
to
connect
to
the
rack
PDU.
You
must
purchase
the
power
cords
that
are
appropriate
for
use
in
a
typical
outlet
in
the
destination
country.
See
for
more
information.
Heat
output,
airflow,
and
cooling
See
for
heat
output,
airflow,
and
cooling
specifications.
Note:
In
general,
disk
subsystem
reliability
tends
to
decrease
as
the
ambient
temperature
of
the
environment
in
which
it
is
being
used
increases.
The
ambient
temperature
in
the
immediate
area
of
the
disk
enclosure
unit
should
be
kept
near
22°
C
(72°
F),
or
lower,
to
provide
better
reliability.
When
racks
that
contain
many
DS4200
Expresss
are
to
be
installed
together,
the
following
requirements
must
be
met
to
ensure
that
the
DS4200
Expresss
are
adequately
cooled:
v
Air
enters
at
the
front
of
the
rack
and
leaves
at
the
back.
To
prevent
the
air
that
is
leaving
the
rack
from
entering
the
intake
of
another
piece
of
equipment,
you
must
position
the
racks
in
alternate
rows,
back-to-back
and
front-to-front.
This
arrangement
is
known
as
“cold
aisle/hot
aisle”
and
is
shown
in
v
Where
racks
are
in
rows,
each
rack
must
touch
the
rack
that
is
next
to
it
to
reduce
the
amount
of
hot
air
that
can
flow
around
from
the
back
of
the
rack
into
the
intakes
of
the
storage
expansion
enclosures
that
are
in
that
rack.
You
should
use
Suite
Attach
Kits
to
completely
seal
any
gaps
that
remain
between
the
racks.
For
details
about
Suite
Attach
Kits,
contact
your
marketing
representative.
v
Where
racks
are
in
rows
front-to-front
or
back-to-back,
a
gap
of
at
least
1220
mm
(48
in.)
must
separate
the
rows
across
the
cold
aisle.
v
To
ensure
correct
airflow
in
each
rack,
the
rack
filler
plates
must
be
installed
in
unused
positions.
Also,
all
the
gaps
in
the
front
of
the
racks
must
be
sealed,
including
the
gaps
between
the
storage
subsystems.
20
IBM
System
Storage
DS4200
Express
Storage
Subsystem:
Installation,
User’s
and
Maintenance
Guide
Summary of Contents for TotalStorage DS4200
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