Computer Equipment Cabinet
When you are concentrating on a difficult
task, there is nothing so disruptive to the process as unexpected
changes in background noise. The mechanical design firm for whom
this was built occupies what is essentially a one room office.
Since they store over a terabyte of data in the form of CAD drawings,
they required some fairly serious data storage capability. Additionally,
poor quality electrical service mandated a hefty UPS (Uninterruptible
Power Supply). But being a firm of 5 or 6 people, they had no
space for a sound-proofed data center. The solution was to encase
all of their equipment into a sound-proofed cabinet with enough
designed-in air flow to keep the equipment cool while keeping
the noise level of the office to a quiet level required for the
designers to focus on their tasks.
As with other commercial projects, pre-finished
melamine boards were used for the visible portion of the cabinet
work itself, since time spent in woodworking is not cost effective
for applications of this nature. This allowed the time to be
spent on soundproofing, airflow, and maintenance design considerations.
The insulating panels (from www.soundprooffoam.com) are made
of recycled fibers, and are more effective for sound-proofing
than many foam materials, and are environmentally responsible
as well. Because of the complex airflow path, it was necessary
to introduce two stages of blowers. The primary inner stage is
4 large 110 VAC powered fans - but noisy. To keep the external
noise down, but to provide the additional airflow, an additional
two rows of 10 each 60mm fans were added to push air from the
inlet to the main fans. These secondary fans required their own
12 VDC power supplies, but more than made up for the trouble
by producing very little noise in the finished project while
keeping the internal temperature within safe levels. Note that
they are also considerably more expensive than the 110 volt fans,
but environmental noise is a significant factor in this office.
Seen above left is the ducting that allows
the airflow load to be handled by a single set of fans. The inlet
ducts which split the fan's airflow are on the right. Above right
is part of the machining operation for mounting the secondary
set of fans in a low-profile setup without having to re-work
the original design. Below left is part of the manufacture of
the support brackets for the secondary fans. A key part of the
design is to make all air flow pass by the soundproofing material
(see below right) so that the internal systems are acoustically
isolated from the outside.
The final product and installation are
intended to produce as little impact on the existing environment
as possible. Even the inside of the door is lined with soundproofing
material. Although difficult to see in the photos, the cabinet
door in the lower right photo shows the steel angle-iron used
to stiffen the door, and some of the batteries used in the extended
UPS (Uninterruptible Power Supply).
The "before and after" pictures
above show the extent to which the equipment area was getting
cluttered with equipment. The final photo (bottom right) also
shows the closed cabinet with the KVM (Keyboard/Video/Mouse)
switch used to administer the systems inside the cabinet. Part
of the secondary inlet fans can also be seen in the photo above
on the right.