Cabling Infrastructure
Schools standardize IT cabinets
Equipment placed in classrooms will
allow for future growth and new
technologies.
The St. Paul School District in Minnesota
recently completed phase one of a multiyear
classroom IT project in K-12 classrooms
across the entire public school system. The
initial phase represented the installation
of more than 500 wall cabinets to improve IT
capabilities in the classroom. The cabinets
were sized to accommodate future growth in
each classroom as new technologies are
integrated into the IT systems.
The cabinets are affixed to the back
wall of each classroom, inches from the
ceiling to deter student contact.
The facilities department initiated the
project after attending an event at a
neighboring school district. There, members
of the school district facilities team and
consultants to the district took notice of
wiring systems for computer classrooms. To
enable convenient data drops to each
computer, the data cabling ran across the
length of each room and into nearby closets.
The St. Paul team used this design as a
basis for its classroom IT plan, adding wall
cabinets to each classroom.
"The wall cabinets represent a
mini-independent distribution frame (IDF) in
each classroom, where we can run wiring
within the classroom for staff and student
computers, as well as back to the main
distribution frame (MDF)," says Janet
Yannarelly, management assistant at St. Paul
School District. "In the long run, it will
be far less expensive to convert a classroom
for another use, such as a computer lab. The
upgrades will be simple and cost-effective
as we move into future phases."
The school district spent $2,000 to
$2,500 per classroom, including the
APWMayville MiniMax cabinets, a Cisco
eight-port data switch and wiring.
"We came into this project with the
understanding that we were going to spend
money, and were looking to the future
instead of the now," she explains. "The
cabinets have enough open space to add more
equipment for future expansion. For now, we
are using some of that extra space to store
wireless base stations and antennas that are
unrelated to the core IT application. If we
need to add another data switch in the
future, we simply rackmount it in the
cabinet and add more wiring to the room."
Each cabinet is approximately 24 inches
by 24 inches by 24 inches and houses the
Cisco switch and a fiber patch panel that
connects to various data drops in the
classroom for computer connections. The
fiber patch panel can handle up to 70
computer connections within the classroom.
Both units are rackmounted inside the
cabinet, affixed to the cabinet sides using
wire strips screwed onto the rackmounts. The
wireless equipment is installed at the
bottom of the cabinet, which allows for
easier access and better security than when
set out in the open or hidden in the
ceiling.
Mike Smith, project manager of Peoples
Electric in St. Paul, led the integration
team over the course of the five-plus year
project. "The extra space in the cabinet
allows for larger fiber panels, and the
extra ports can be used to simplify cable
runs if a classroom wants to add more
computers," he offers. "Instead of making
150- to 200-foot cable runs down the
hallways, the staff can make 50- to 70-foot
runs inside the classroom."
Wiring to and from the classroom
computers is run directly into the cabinet
through an access hole in the cabinet.
Vertically mounted power strips provide
electrical outlets for the eight-port
switch, providing all the juice for the IT
system in the classroom. Power injectors
sometimes accommodate power for the wireless
systems within the cabinets. More often,
externally powered switches provide direct
data runs between the wireless antenna and
the local IDF or MDF.
An Ethernet fiber backbone connects the
Cisco switches from each cabinet to the
school's main server, with CAT 6 cables
providing server connections and electrical
power between the MDF, local IDFs and the
cabinets. Most schools have one IDF,
typically in a dedicated wiring closet on
each floor. Some schools with expansive
square footage per floor require additional
IDFs per floor to accommodate distances of
300 feet or more to the MDF. A UPS system
backs up all power on the main server rack
in the MDF.
The MiniMax cabinets are affixed to the
back wall of each classroom, inches from the
ceiling to deter student contact.
Maintenance can be performed from the front
or rear, as the cabinet swings out from the
support piece to the left or right for rear
access to the equipment. The front doors are
secured with a sturdy lock system, to which
only technicians and some administrators
have access.
The lack of equipment density within the
cabinet keeps heat levels to a minimum.
Noise was initially an issue with the
eight-port switches, and the noise flowing
through the perforated cabinet sides became
a distraction in some classrooms. Thin
insulation pads were installed to solve the
noise problem, without drastically raising
the heat levels within the cabinets.
According to Yannarelly, the APWMayville
cabinets were evaluated alongside several
competitive products. "We probably looked at
four or five different solutions, but the
APWMayville cabinets were the most
cost-effective," she says. "They also met
our requirements for depth, which was
important considering the depth of the port
switches. We were also seeking a smaller
cabinet in terms of height, and no other
cabinet fit the size we needed for either
height or depth. The cabinets have also
proven durable, easily handling the weight
of the components."
Yannarelly expects to integrate smart
boards and projectors into classrooms to
provide interactive environments for the
students. He says these items will be
connected to the cabinets, given the
additional space currently in most cabinets.
"Any data we require for these upgrades
would likely run direct to power strips in
the cabinets," says Yannarelly. "It makes
more sense to run these within the classroom
rather than to an external wiring closet. It
reduces complexity and keeps our wiring
costs to a minimum, allowing us to remain
fiscally responsible as we add new
technology. These cabinets will be a big
help to us in the future through the
flexibility they provide in the classroom."
For more information from
APWMayville
(click here)