Honeycomb Ventilation Panels

Series No. 3000

MAJR’s line of ready-to-install EMI/RFI honeycomb filters and Waveguides provide optimum EMI/RFI shielding with minimum pressure drop for the ventilating air. Shielded vent panel effectiveness is accomplished using waveguide honeycomb design principles.

The choice of which honeycomb filter or waveguide will best meet your design considerations is based on three main criteria: shielding, air flow and mounting. For most applications, aluminum code-32 honeycomb (properly installed using MAJR’s mounting frame with integral EMI/RFI gasket) will provide a degree of attenuation that will be within specification limits (see table 1). However, for the lower frequency range (H-field), it may be necessary to specify MAJR’s material tin plated steel code-44.

Their special design lets air flow into and out of an EMI/RFI shielded enclosure. This feature allows for the cooling of electronics as well as air circulation for manned military shelters as well as electronic boxes and cabinets. The circulating air can also be used to either heat or cool an area depending on the external environment.

Overview

MAJR’s Honeycomb Ventilation Panels provide optimum electromagnetic/radio frequency interference (EMI/RFI) shielding with minimum pressure drop while ventilating air. Shielding effectiveness is accomplished using waveguide design principles.

Product Features:

  • Built to Your Specifications: MAJR’s engineering team can assist with applications requiring special mounting or shape.
  • Optimum Shielding and Air Flow: Installation of the honeycomb filter—with its 4:1 opening-to-depth ratio—provides the waveguide below cut-off effect required to attenuate EMI/RFI interference while not impeding the air flow required to cool the packaged enclosure.
  • Standard Configurations: MAJR offers a wide variety of standard sizes, as seen below, which can reduce lead-time and setup charges for our customers.

Standard Products

Figure 1 -Style 3031 Honeycomb Filter with Through Holes


 
air_filtration_panels_02

Table 1

Part_Number_
OPENING (inches) FRAME DIMENSIONS (inches)
Width Length AA BB A B C D E F G H J
3031-20303-XX 3.00 3.00 4.00 4.00 3.50 3.50 1.75 1.75 4
3031-20305-XX 3.00 5.00 6.00 4.00 5.50 3.50 1.00 1.75 1 3.50 6
3031-20311-XX 3.00 11.00 12.00 4.00 11.50 3.50 1.25 1.75 3 3.00 10
3031-20404-XX 4.00 4.00 5.00 5.00 4.50 4.50 .750 2.25 1 3.00 6
3031-20409-XX 4.00 9.00 10.00 5.00 9.50 4.50 1.25 2.25 2 3.50 8
3031-20505-XX 5.00 5.00 6.00 6.00 5.50 5.50 1.00 1.00 1 3.50 1 3.50 8
3031-20511-XX 5.00 11.00 12.00 6.00 11.50 5.50 1.25 1.00 3 3.00 1 3.50 12
3031-20606-XX 6.00 6.00 7.00 7.00 6.50 6.50 1.50 1.50 1 3.50 1 3.50 8
3031-20609-XX 6.00 9.00 10.00 7.00 9.50 6.50 1.25 1.50 2 3.50 1 3.50 10
3031-20714-XX 7.00 14.00 15.00 8.00 14.50 7.50 .750 .750 4 3.25 2 3.00 16
3031-20909-XX 9.00 9.00 10.00 10.00 9.50 9.50 1.25 1.25 2 3.50 2 3.50 12
3031-21111-XX 11.00 11.00 12.00 12.00 11.50 11.50 1.25 1.25 3 3.00 3 3.00 16
3031-21414-XX 14.00 14.00 15.00 15.00 14.50 14.50 1.25 1.25 4 3.00 4 3.00 20
3031-21818-XX 18.00 18.00 19.00 19.00 18.50 18.50 1.75 1.75 5 3.00 5 3.00 24

 
 

Table 2 – Style 3033  Honeycomb Filter with Through Holes

Part_Number_
OPENING (inches) FRAME DIMENSIONS (inches)
Width Length AA BB A B C D E F G H J
3033-20303-XX 3.00 3.00 4.25 4.25 3.50 3.50 1.75 1.75 4
3033-20305-XX 3.00 5.00 6.25 4.25 5.50 3.50 1.00 1.75 1 3.50 6
3033-20311-XX 3.00 11.00 12.25 4.25 11.50 3.50 1.25 1.75 3 3.00 10
3033-20404-XX 4.00 4.00 5.25 5.25 4.50 4.50 .750 2.25 1 3.00 6
3033-20409-XX 4.00 9.00 10.25 5.25 9.50 4.50 1.25 2.25 2 3.50 8
3033-20505-XX 5.00 5.00 6.25 6.25 5.50 5.50 1.00 1.00 1 3.50 1 3.50 8
3033-20511-XX 5.00 11.00 12.25 6.25 11.50 5.50 1.25 1.00 3 3.00 1 3.50 12
3033-20606-XX 6.00 6.00 7.25 7.25 6.50 6.50 1.50 1.50 1 3.50 1 3.50 8
3033-20609-XX 6.00 9.00 10.25 7.25 9.50 6.50 1.25 1.50 2 3.50 1 3.50 10
3033-20714-XX 7.00 14.00 15.25 8.25 14.50 7.50 1.50 1.50 3 3.50 1 3.50 16
3033-20909-XX 9.00 9.00 10.25 10.25 9.50 9.50 1.25 1.25 2 3.50 2 3.50 12
3033-21111-XX 11.00 11.00 12.25 12.25 11.50 11.50 1.25 1.25 3 3.00 3 3.00 16
3033-21414-XX 14.00 14.00 15.25 15.25 14.50 14.50 1.25 1.25 4 3.00 4 3.00 20
3033-21818-XX 18.00 18.00 19.25 19.25 18.50 18.50 1.75 1.75 5 3.00 5 3.00 24

 
 

Table 3 – Style 3036 Honeycomb Filter with Through Holes

Part_Number_ OPENING (inches) FRAME DIMENSIONS (inches)
Width Length AA BB A B C D E F G H J
3036-20303-XX 3.00 3.00 5.25 5.25 4.50 4.50 2.25 2.25 4
3036-20305-XX 3.00 5.00 7.25 5.25 6.50 4.50 1.75 2.25 1 3.50 6
3036-20311-XX 3.00 11.00 13.25 5.25 12.50 4.50 1.75 2.25 3 3.00 10
3036-20404-XX 4.00 4.00 6.25 6.25 5.50 5.50 1.00 1.00 1 3.50 1 3.50 8
3036-20409-XX 4.00 9.00 11.25 6.25 10.50 5.50 .75 1.00 3 3.00 1 3.50 12
3036-20505-XX 5.00 5.00 7.25 7.25 6.50 6.50 .50 1.50 2 2.75 1 3.50 10
3036-20511-XX 5.00 11.00 13.25 7.25 12.50 6.50 1.00 1.50 3 3.50 1 3.50 12
3036-20606-XX 6.00 6.00 8.25 8.25 7.50 7.50 .75 .75 2 3.00 2 3.00 12
3036-20609-XX 6.00 9.00 11.25 8.25 10.50 7.50 .75 .75 2 3.00 2 3.00 14
3036-20714-XX 7.00 14.00 16.25 9.25 15.50 8.50 .75 .75 4 3.50 2 3.50 16
3036-20909-XX 9.00 9.00 11.25 11.25 10.50 10.50 .75 .75 3 3.00 3 3.00 16
3036-21111-XX 11.00 11.00 13.25 13.25 12.50 12.50 1.00 1.00 3 3.50 3 3.50 16
3036-21414-XX 14.00 14.00 16.25 16.25 15.50 15.50 .75 .75 4 3.50 4 3.50 20
3036-21818-XX 18.00 18.00 20.25 20.25 19.50 19.50 .75 .75 6 3.00 6 3.00 28

Technical Information

Shielding Effectiveness vs Frequency — Table 4

Shielding Effectiveness dB

Field Aluminum – Chromate Finish Material Code – 32
Frequency
100
kHz
1
MHzh
18
MHz
100
MHz
400
MHz
1
GHz
10
GHz
H 35 50
E 75
PW 75 75 65 50

The data in Table 4 shows shielding characteristics for standard MAJR shielded vents. Note that the data indicated is based on a unit whose opening was 12.00 x 12.00 (305 x 305 mm) and tested under laboratory conditions per MIL-STD 285.

Table 4 (Continued)

Shielding Effectiveness dB

Field Aluminum – Tin Plate Material Code – 42
Frequency
100
kHz
1
MHzh
18
MHz
100
MHz
400
MHz
1
GHz
10
GHz
H 65 80
E 100
PW 95 95 95 90
Field Steel – Tin Plate Material Code – 44
Frequency
100
kHz
1
MHzh
18
MHz
100
MHz
400
MHz
1
GHz
10
GHz
H 75 80
E 110
PW 110 110 110 100

 

Design Data: Airflow

MAJR - Chart 1MAJR - Chart 2
MAJR - Chart 3 MAJR - Chart 4

 

Product Data Sheet

Product Options

Figure 1 -Style 3031 Honeycomb Filter with Through Holes