Application and Design Guide to
EMI Shielding Honeycomb Vents
Contents
1
How to Use This Guide 1
What is an EMI Shielding Honeycomb Vent? 2
Application Design Assistance 2
Honeycomb Technical Specifications 5
Frames 7
Plating 10
Common Gasket Options 12
Honeycomb Performance Test Data 15
Value-Added Options 16
Standard Parts Summary 18
For those who are unfamiliar with EMI shielding honeycomb vent
design, it is recommended to rst study the Application Design Assistance
section, to become familiar with the basic variables associated with
EMI shielding vents, their common uses and general limitations.
ose who are already familiar with EMI shielding vent design may
simply refer to the appropriate technical data within this document.
Contact Parker Chomerics with any additional design or product
information questions. Call Parker Chomerics directly at
(781) 935-4850 where an application engineer can assist you or
visit chomerics.com for up-to-date catalog information.
How to Use This Guide
is necessary to ensure long-term
assembly performance.
Application-specic performance
can be changed by modifying
the size and other associated
features of the vent assembly.
Design requirements such as,
but not limited to, attenuation
values, airow rates and direction,
corrosion prevention, durability,
air particulate ltration and ame
resistance can be achieved.
A honeycomb vent is either
free-standing metallic alloy
honeycomb or an assembly
incorporating the honeycomb
with other value-added features
such as framing, plating,
gasketing, lters, etc.
ese vents are typically
incorporated into enclosures
where EMI radiation or
susceptibility is a concern, as
well as where heat dissipation
Application Design Assistance
2
What is an EMI Shielding Honeycomb Vent?
Many design variables should be considered when developing
an EMI shielding honeycomb vent design. Some features are
mandatory to ensure correct application performance.
Others exclusively oer convenience or improved performance.
Design Variables Summary
e following section is to be
used as a brief reference to the
variables associated with typical
honeycomb vent assembly design.
For more in-depth information,
please reference the additional
information provided as this
guide progresses.
Airow
Airow performance is inversely
proportional to attenuation
performance. Innite metal
results in innite shielding but
no airow, and vice versa.
ree major factors should be
considered when determining
airow performance. Listed
in order of typical impact on
performance are the following:
1.
As cell size decreases, airow
performance decreases.
2. As honeycomb thickness
increases, greater air turbulence
occurs within cells, resulting in
decreased airow.
3. Additional layers of value-added
features (foam lters, etc.) will
decrease airow.
Because of the intimate
relationship between attenuation
and airow, a careful evaluation
and prioritization of technical data
is recommended to ensure optimal
overall performance of the vent
assembly.
Airflow
examples