Additional Capabilities - Fluke 975 AirMeter Application Note

The first situation usually
occurs because a user of the data
center does not need all eight
slots in a rack or because the
data center lacks the capability
to provide power to a full rack.
In either case, there are empty
slots. Blanking panels should
cover those unused slots so that
they are not open to the environ-
ment.
The analyst says that he has
documented instances of miss-
ing blanking panels at the firm's
secondary center. "There were
empty spaces on the top four
slots," he says. "Nobody could
believe it, but hot air from the
backs of the servers was circu-
lating over the tops of the racks
and coming right back in the
front. That greatly increased the
temperature of the blades and
decreased their efficiency. We
needed to fill the tops of those
racks with blanking plates."
The best strategy for a data
center—especially a data center
with blade servers—is to install
servers back-to-back in rows
facing the fronts of servers in
adjacent rows. This creates alter-
nating cold aisles and hot aisles.
"A lot of data centers are set
up with one row of servers after
another—back to front, back to
front, back to front," he says dis-
approvingly. "The hot air from
one row of servers blows onto
the fronts of the next row, and
that's continued throughout the
center. In Europe, we are looking
for a center with alternating hot
and cold aisles."
Safeguarding server war-
ranties is the analyst's principal
impetus for monitoring the law
firm's servers. "Our blade manu-
facturer has a recommended
maximum temperature that serv-
ers can reach. If a server gets
above that threshold, it is no lon-
ger covered under our warranties
and contracts. That would be a
huge problem for us."
Because of these warranty
considerations, company per-
sonnel need to verify what data
center owners tell them about
the cooling in their facilities. And
while the blades themselves
3 Fluke Corporation Monitoring temperature, humidity, and airflow in datacenters
have internal monitors that track
their temperatures, the analyst
needs know how effectively the
cooling supplied by the data cen-
ter is doing the job.
He uses the Ti0 to collect
thermal images of the fronts
of the blades to determine the
temperature of the air flowing
in. Then, he compares this tem-
perature to the temperature of
the air coming out the back of
the rack. Finally, he compares
these temperatures to the blade
manufacturer's recommended
temperature threshold for the
servers.
"If necessary," he says, "we
can go back to a data center's
owners and say, 'This is the air-
flow that you are telling us we're
getting, and this is what we see.
You're not meeting our require-
ments. We need you to upgrade
your systems to make sure you
meet our specifications.'"

Additional capabilities

with the Fluke 975
The Fluke 975 AirMeter allows
the analyst to precisely measure
air temperatures and convert the
air-meter data into reports for
superiors or data center opera-
tors. Using the Ti0 Thermal
Imager and the 975 AirMeter
together "provides results from
different angles," he says. "If we
use the imager to reveal the sur-
face temperatures, then we can
use the airflow meter to register
the actual temperature of the air
going into racks."
The 975 AirMeter also mea-
sures relative humidity (RH)
and airflow. Excessive humid-
ity in a data center can lead
to condensation on equipment
and places an undue load on
the air-conditioning system. RH
readings played a significant
role in uncovering difficulties at
the local data center. Regard-
ing airflow, "In our primary and
secondary data centers, the air
comes in through the floors,"
he says. "We can use the air-
flow sensor on the 975 to make
sure that airflow is at the rate
required by our servers."
Creating tracking
databases
The analyst's job includes creat-
ing and maintaining tracking
databases. To do this, he peri-
odically uses the Ti0 to make
images at specific points in the
primary and secondary data cen-
ters. He then logs the data into
the database for review as nec-
essary. "We can graph the data
for each location and see if the
temperature is rising, falling or
staying the same over time," he
explains.
Equipment frequently moves
within data centers, as clients
expand their server capacity or
stop using the center altogether.
If the law firm brings a new
piece of equipment into a data
center or reacts to a temperature
problem by moving an existing
server, the tracking database
allows them to assess how the
change affected ambient tem-
peratures.
From such findings, the sup-
port analyst, in cooperation with
data center personnel, can deter-
mine when the center needs
more cooling or when equip-
ment is packed in too densely.
In general, the database lets the
law firm and data center person-
nel pinpoint areas where the
air is more or less cool or where
there is more or less airflow. The
analyst speculates that as he
becomes more familiar with the
975 AirMeter and its data logging
capabilities, it will play a greater
role in his tracking databases.
Fluke. Keeping your world
Fluke Corporation
PO Box 9090, Everett, WA USA 9806
Fluke Europe B.V.
PO Box 1186, 560 BD
Eindhoven, The Netherlands
For more information call:
In the U.S.A. (800) 443-5853 or
Fax (45) 446-5116
In Europe/M-East/Africa +31 (0) 40 675 00 or
Fax +31 (0) 40 675 
In Canada (800)-36-FLUKE or
Fax (905) 890-6866
From other countries +1 (45) 446-5500 or
Fax +1 (45) 446-5116
Web access: http://www.fluke.com
©007 Fluke Corporation. All rights reserved.
Specifications subject to change without notice.
Printed in U.S.A. 5/007 3034678 A-EN-N Rev A
up and running.
®