Electronics Protection - Summer 2016 - (Page 12)
Cool it Your Way: Versatile Cooling for
Justin Moll, Vice President, US Market Development
Electronics enclosures are used in countless test/analytics/measurement devices for multiple end markets. This includes various instrument systems in Oil & Gas, industrial and
power control, medical, lab/test and military designs. The end applications are too numerous to name. But, serving all of these types of devices requires a wealth of cooling options
for instrument cases.
There are a wide range of cooling options to consider for sheet metal and aluminum enclosures: incorporating fans, partial top perforation for heat exhaust, full top perforation
for higher exhaust requirements, bottom and top perforation (often for external fan trays
or other cooling, and front and/or rear panel perforation in various types. We'll leave out
the more exotic other options for cooling that include liquid, conduction-hybrids, etc.
Now consider a line of modular enclosures. To provide standard aluminum enclosures in
1U to 14U heights, widths at 19 or 9.5 inches, or compact sizes, and depths from 250 mm
to more than 500 mm, there are a lot of configurations. Providing every one of the above
cooling options is not always available standard in every size, but customization can typically be kept to an absolute minimum. That means a standard or "modified standard" tailored
enclosure solution that gets to market quickly and keeps development and production
Figure 1. There are various
Figure 1a shows a top perforated cover on an enclosure for natural convection, Fig 1b for
top and bottom airflow, and Fig 1c for perforations in the top, bottom, and rear of the
instrument case. Clearly, more openings allow more heat evacuation. Many of today's
instruments and devices that use metal enclosures have an internal fan on a device and/or
another cooling option such as using heat sinks/conduction. Of course, completely enclosed options are available too. However, placing a fan tray at the bottom of the enclosure
is another common option. Alternatively, fans can be incorporated into the rear (typically)
panel. Often, these are standard 120 mm muffin fans, but other sizes are certainly possible.
See Figure 2 for an example. For access into the enclosure, it is common for these panels to
be hinged on the side or the bottom. This allows for maintenance or replacement of parts
and general access to the device.
Feet and Stands for More Airflow
Many desktop enclosures come with standard "feet" options. These are not just aesthetics.
The feet can help angle the enclosure for easier viewing, prevent scratches on the desktop,
and provide spacing between the bottom of the enclosure and the desk/surface to allow
airflow. (See Figure 3) The carry handle could also act as a stand to prop up the enclosure
and achieve these same goals. The dual function is very convenient for devices that need to
be transported often. It also provides a nice aesthetic appearance.
Instead of standard feet, there are stands that help attain the same goal. These end caps
also provide a stand-off and protect a desktop or lab bench from direct contact from the
metal case. The enclosure in Figure 4 shows how a clever design allows multiple enclosures
to be stacked. The top of the enclosure has a shape on the edge of the bezel that allows a
similar enclosure placed above it to securely fit.
Summer 2016 * www.ElectronicsProtectionMagazine.com
perforation options for
venting of enclosures. Fig
1a) top venting. Fig 1b)
top and bottom venting.
Fig 1c) top, bottom and
Figure 2. Incorporating
rear evacuative fans does
not require customization.
Rear panels with fans cutouts are not uncommon.
Figure 3. Enclosure feet
have benefits, including
angling, bottom venting
for cooling, and protecting
surfaces from scratches.
Table of Contents for the Digital Edition of Electronics Protection - Summer 2016
Electronics Protection - Summer 2016
Common Coolant Types and Their Uses in Liquid Cooling Systems
The Benefits of Vertical Integration for Customized EMI Shielding Products and Services
Cool It Your Way: Versatile Cooling for Electronics Enclosure
Heat Pipes and Vapor Chambers – What’s the Difference?
Securing Electronics in Modern Railway Systems
Calendar of Events
Electronics Protection - Summer 2016