Parker Hannifin PA Series - Manual (Page 14)

Chapter 2: Installing the PowerStation Selecting a Location
PA PowerStation User Guide
2-3
PA PowerStation’s have been tested for use in 50 o
C
ambient, still air
locations. This means that when installed, the ambient air surrounding the
backside of the PowerStation is not expected to exceed 50 o
C
. An example
of this type of installation would be a PowerStation mounted in a small,
sealed industrial enclosure.
The most commonly overlooked aspect of this type of installation is that
heat generated by the device becomes trapped inside the enclosure and
increases the ambient temperature surrounding the PowerStation. This
increase in temperature can sometimes exceed an additional 15 o
C
or more.
Although the thermal dynamics are not always linear, a temperature rise of
15 o
C
would imply that the environment outside the sealed enclosure could
not exceed 35 o
C
(95 o
F
), or the PowerStation would surpass its maximum
operating temperature.
Do not mount a PowerStation into a sealed enclosure and mistakenly think
that due to the 50 o
C
rating of the product, the sealed enclosure can
operate in a 50 o
C
ambient environment without considering the affects of
the internal heat build up.
Since elevated operating temperatures can have negative affect on the life
of electronics, it is wise to consider the internal thermal rise. Passive
venting for thermal convection, internal air circulation fans, filtered
exhaust fans with filtered inlets, air conditioners, and other products are
available in the market to assist in reducing the heat build up in the
industrial enclosure.
There are many attractive NEMA Type 12, dust-tight fan/filter assemblies
available today in which the filter can be inexpensively replaced or cleaned
as part of a periodic maintenance schedule. Or in some cases, simply
increasing the size of the enclosure, and thus the outside surface area for
example, can have a significant, positive affect on the installation’s thermal
response.
Points to consider when performing a site review are:
1
What is the expected maximum outside ambient temperature that
the industrial enclosure will experience?
2
Are there additional heat-generating components inside the
enclosure?
3
What is the size of the enclosure? Larger enclosures dissipate more
thermal energy than smaller ones.
4
In what kind of environment will the enclosure be installed - clean,
water-tight, dust-tight? Can the enclosure be convection cooled or is
active cooling required?
In summary, it is a wise investment to thermally plan the installation by
anticipating, and eliminating, the heat build up inside a sealed enclosure.
Not only will this extend the life of the electronics, but it will also reduce
costly equipment downtime.