Honeycomb Ventilation Panels
EMI/RFI Shielded Ventilation Panels 3000 Series
MAJR’s line of ready-to-install EMI/RFI honeycomb ventilation panels provide optimum EMI/RFI shielding with minimum pressure drop for the ventilating air. Shielded vent panel effectiveness is accomplished using waveguide honeycomb design principles.
Choosing the right Honeycomb Ventilation Panels that 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.
Create CAD Drawings for Standard EMI/RFI Shielded Ventilation Panels
Standard Products
Table 1 – Style 3031 Honeycomb Ventilation Panel with Through Holes
| 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 |
Replace -XX with the following: -32 (chromate aluminum), -42 (tin aluminum), -43 (brass), -44 (tin steel), -90 (RoHS compliant)
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 |
Replace -XX with the following: -32 (chromate aluminum), -42 (tin aluminum), -43 (brass), -44 (tin steel), -90 (RoHS compliant)
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 |
Replace -XX with the following: -32 (chromate aluminum), -42 (tin aluminum), -43 (brass), -44 (tin steel), -90 (RoHS compliant)
Custom Product
Technical Information
Shielding Effectiveness vs Frequency — Table 4
Shielding Effectiveness dB
| Field | Aluminum – Non-hexavalent Chromate Finish Material Code – 90 Frequency |
|||||
| 1 MHz |
100 MHz |
500 MHz |
1 GHz |
10 GHz |
18 GHz |
|
| E | 60 | 50 | 50 | — | — | — |
| PW | — | — | — | 45 | 40 | 30 |
| Field | Aluminum – Tin Plate Material Code – 42 Frequency |
||||||
| 1 MHz |
100 MHz |
500 MHz |
1 GHz |
10 GHz |
18 GHz |
||
| E | 100 | 90 | 85 | — | — | — | |
| PW | — | — | — | 80 | 70 | 60 | |
| Field | Brass – Material Code – 43 Frequency |
||||||
| 1 MHz |
100 MHz |
500 MHz |
1 GHz |
10 GHz |
18 GHz |
||
| E | 105 | 95 | 90 | — | — | — | |
| PW | — | — | — | 85 | 75 | 65 | |
| Field | Steel – Tin Plate Material Code – 44 Frequency |
|||||||
| 10 kHz |
100 kHz |
1 MHz |
100 MHz |
500 MHz |
1 GHz |
10 GHz |
18 GHz |
|
| H | 45 | 60 | — | — | — | — | — | — |
| E | — | — | 110 | 110 | 110 | — | — | — |
| PW | — | — | — | — | — | 110 | 80 | 70 |
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” using a 0.5” x .125” cell size honeycomb and tested under laboratory conditions per MIL-STD 285. This data is for comparison between shielded vent panel configurations and is not to be stated as a pass/fail specification for a manufactured EMI/RFI honeycomb vent panel.
Yellow chromate finish available upon request – 32
Tin Plated Steel data reflects a steel honeycomb and steel frame construction. Not all mounting frame options are available in steel.
Design Data: Airflow
Product Data Sheet
Product Options
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.
Figure 1 -Style 3031 Honeycomb Filter with Through Holes
