EMI shielded vents

Lightweight aluminium honeycomb vents can be mounted onto most forms of EMI shielded enclosure where airflow is needed, either over cooling fans or by convection. They can be mounted anywhere on the enclosure and can be fitted with protective ‘kickplates’ to protect the honeycomb material from accidental damage.

Where they may be exposed to the elements the aluminium honeycomb vents can be fitted with ‘slant’ honeycomb which provides a downward facing aperture, preventing the ingress of rainwater. This has the added benefits of directional airflow and increased attenuation due to the higher aspect-ratio of the cell structure.

Honeycomb ventilation panels are usually supplied with gaskets in a ready-to-mount form which either fits around the aperture in the equipment (non-flanged style) or is inset into the enclosure (flanged style). Depending on the performance requirements for the application, they can be mounted by bolting through clearance holes in the frame, through the use of captive threaded inserts.

Aluminium honeycomb material is formed by expanding a bonded aluminium foil into a honeycomb structure. This process, which is common to all honeycomb manufacturers, produces a material which is ‘polarized’ and is conductive either horizontally or vertically. To overcome polarisation problems two layers of honeycomb, mounted at 90 degrees to each other, are used. Please contact us for further information about polarisation.

Each cell in an attenuation vent acts as a waveguide and its performance is a function of its width/height and the ratio between the depth and width of the cell. Generally an aspect ration of 4 or 5:1 is used.

Aluminium honeycomb vents are finished to suit specific applications and can be protected by Alocrom 1000, 1200, Iridite or electroplating.