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Metex EMI vent
panels provide maximum attenuation with minimal air-flow resistance.
Shielding effectiveness is greater than 80 dB at 10 MHz for chromate
finished, single layer honeycomb, and is increased to 105 dB
using our cross cell construction. By selecting the appropriate
frame style, finish, and gasket type, performance can be custom
tuned to meet your shielding requirements, and your budget constraints.
Vent
panels are constructed of aluminum alloy honeycomb, with a
perimeter frame of aluminum extrusion for mounting and gasket
application. Various gasket options include wire mesh, spring
finger, or conductive fabrics.
Honeycomb Shielding
Aluminum: The standard structure is 1/8" cell adhesive bonded honeycomb,
available in 1/2" or 1/4" thickness. Steel and Brass honeycomb shields are
available on a custom basis.
Shielded Mesh Screens
Shielded Mesh Screens replace honeycomb media with several layers of
woven wire mesh. They are designed for use on shielded electronic enclosures
which require filtered air. Mesh screens are easily removable for cleaning.
Framing Options
Standard frame material is extruded aluminum 6063 T-4 alloy. Various C-frame
cross sectional configurations are shown on page 2. Many other sizes
and styles are available. EMI gasket options include wire mesh and elastomer,
groove mounted wire mesh, spring finger gaskets, Metex oriented wire
or Metex CF conductive fabric over foam gaskets.
Mounting
Panels are typically mounted to an enclosure using captive threaded inserts,
and threaded fasteners.
Shielding Effectiveness
Depending on their size, type of material, finish and gasket type used, vent
panels vary in shielding effectiveness. As an example, a 12" square, tin plated
aluminum vent panel with a wire mesh gasket, will provide greater than
90 dB of attenuation, at 1 GHz plane wave. Metex can provide shielding
effectiveness data for your specific vent panel design.
EMI Vent Panel Construction
The cross sections shown to the left depict the construction of the basic Cchannel
vent panel, with examples of the material codes from the materials
table. Many other frame styles and materials are available. Consult a Metex
Shielding Applications Engineer for design assistance.
Standard gasket construction consists of knitted monel wire mesh, bonded
to a neoprene sponge gasket. For other gasket materials, please consult a
Metex Shielding Sales Engineer.
Vent Panels
| Digit |
|
Frame |
|
Filter |
|
Finish (F) |
|
Fastener |
| 1 |
|
3/8" aluminum C channel |
|
1/16" cell single layer, aluminum H/C |
|
Mil-C-5541 iridite |
|
None
.204 D through hole |
| 2 |
|
1/2" aluminum C channel |
|
1/16" cell double layer, aluminum H/C |
|
Mil-T-10727 type 1 tin |
|
6-32 threaded captive insert |
| 3 |
|
Flush mount aluminum |
|
1/8" cell single layer, aluminum H/C |
|
Electroless nickel |
|
9-32 threaded captive insert |
| 4 |
|
———— |
|
1/8" cell double layer, aluminum H/C |
|
———— |
|
M-4 threaded captive fastener |
| 5 |
|
———— |
|
1/8" cell, 60 degree single layer alum. H/C |
|
———— |
|
———— |
| 6 |
|
———— |
|
1/8" cell, 60 and 90 degree double layer alum. H/C |
|
———— |
|
———— |
Airspeed vs.Airflow Resistance
Resistance to air flow is extremely low in all panel designs, although varying from
style to style. In particular, airflow resistance with steel and brass honeycomb is
approximately double that of aluminum honeycomb. Airspeed vs. airflow resistance is
charted for typical vent panels below.
When the outer honeycomb is slanted at 60° from horizontal intake axis than at
30°, an increase to the resistance to airflow will occur.
Cross Sections
706-23F3
1/8" cell, single layer H/C with 8-32 captive fastener.
706-24F1
1/8" cell, double layer H/C with .204D
through hole (not shown).
706-13F1
1/8" cell, single layer H/C with .204D
through hole (not shown).
KEY FEATURES
- Maximum Shielding with
minimum pressure drop
- Lightweight aluminum
honeycomb
- Many mounting styles
and gasket options to
suit your application
- Custom designs available
- No polarization effects
- Panel frames fully gasketed
- All honeycomb panels
can be mounted in
circular frames
- Ready to install
Frame Dimensions (inches)
| Part Number* |
|
Vent
Opening |
|
A |
|
B |
|
C |
|
D |
|
E |
|
F |
|
G |
|
H |
| 706-2XXX-9903-03 |
|
3X3 |
|
4.00 |
|
4.00 |
|
1.75 |
|
— |
|
— |
|
— |
|
— |
|
— |
| 706-2XXX-9903-05 |
|
3X5 |
|
4.00 |
|
6.00 |
|
1.75 |
|
1.00 |
|
— |
|
— |
|
1 |
|
3.50 |
| 706-2XXX-9903-11 |
|
3X11 |
|
4.00 |
|
12.00 |
|
1.75 |
|
1.25 |
|
— |
|
— |
|
3 |
|
3.00 |
| 706-2XXX-9904-04 |
|
4X4 |
|
5.00 |
|
5.00 |
|
2.25 |
|
0.75 |
|
— |
|
— |
|
1 |
|
3.00 |
| 706-2XXX-9904-09 |
|
4X9 |
|
5.00 |
|
10.00 |
|
2.25 |
|
1.25 |
|
— |
|
— |
|
2 |
|
3.50 |
| 706-2XXX-9905-05 |
|
5X5 |
|
6.00 |
|
6.00 |
|
1.00 |
|
1.00 |
|
1 |
|
3.50 |
|
1 |
|
3.50 |
| 706-2XXX-9905-11 |
|
5X11 |
|
6.00 |
|
12.00 |
|
1.00 |
|
1.25 |
|
1 |
|
3.50 |
|
3 |
|
3.00 |
| 706-2XXX-9906-06 |
|
6X6 |
|
7.00 |
|
7.00 |
|
1.50 |
|
1.50 |
|
1 |
|
3.50 |
|
1 |
|
3.50 |
| 706-2XXX-9906-09 |
|
6X9 |
|
7.00 |
|
10.00 |
|
1.50 |
|
1.25 |
|
1 |
|
3.50 |
|
2 |
|
3.50 |
| 706-2XXX-9907-14 |
|
7X14 |
|
8.00 |
|
15.00 |
|
0.75 |
|
0.75 |
|
2 |
|
3.00 |
|
4 |
|
3.25 |
| 706-2XXX-9909-09 |
|
9X9 |
|
10.00 |
|
10.00 |
|
1.25 |
|
1.25 |
|
2 |
|
3.50 |
|
2 |
|
3.50 |
| 706-2XXX-9911-11 |
|
11X11 |
|
12.00 |
|
12.00 |
|
1.25 |
|
1.25 |
|
3 |
|
3.00 |
|
3 |
|
3.00 |
| 706-2XXX-9914-14 |
|
14X14 |
|
15.00 |
|
15.00 |
|
1.25 |
|
1.25 |
|
4 |
|
3.00 |
|
4 |
|
3.00 |
| 706-2XXX-9918-18 |
|
18X18 |
|
19.00 |
|
19.00 |
|
1.75 |
|
1.75 |
|
5 |
|
3.00 |
|
5 |
|
3.00 |
* Specify 23F3, 24F1, or 13F1 from cross sections shown on page 2 (left).
Specify “F” as 1, 2 or 3 for Finish
This is only a small listing of possible sizes, shapes and combinations.
For other sizes and materials, please contact Metex Shielding Sales Engineering at 732-287-0800.
PRODUCT APPLICATIONS
- Shielding for
Containment—
To prevent escape of
most or all of the interference
generated by a
particular device, circuit
or system as a disturbing
source
- Shielding for
Exclusion—
To prevent the intrusion
of anticipated or known
levels of interference on
the performance of a
specific device, circuit or
system
- Exclusion/Containment
Shielding Plus
Pressure Sealing—
To provide pressure containment
as well as
EMI/RFI attenuation
- Grounding and
Contacting— Not to contain or
exclude but to conduct
electrical current such as
discharging electrostatic
energy from imperfectly
grounded structures to
ground, providing a
dependable, low impedance
connection
between removable circuit
assemblies and the
host circuit ground plane
and/or power busses,
thus ensuring good contact
between large or
massive electrical structures
that do not mate
mechanically due to
dimensional tolerance
In all of these applications,
the solution is found
in the use of highly resilient,
high-conductive shielding
materials.
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