We have a comprehensive range of EMC or EMI Shielding Ventilation Panels and filters available that are all primarily designed to allow unrestricted air-flow whilst preventing the transmission of electromagnetic interference (EMI). They are used wherever there is a requirement for air cooling or to allow ventilation without compromising the shielding integrity of an enclosure.
The main types of EMI Filter panels are:
- Cut to shape/size Honeycomb
- Honeycomb Vent Panels
- Low Profile Vent Panels
- EMI Shielding Dust Filters
- High Performance/EMP Vent Panels
- Low Cost Vent Panels
Honeycomb vent panels
The most commonly used type of vent is based on aluminium honeycomb panels mounted in an extruded aluminium frame. The honeycomb media has a very high open area and therefore allows good air flow with minimal pressure drop. In order to achieve the best shielding performance two layers of honeycomb are used orientated at 90° to one another, although this is not always necessary on some less demanding applications. The exterior facing honeycomb layer can be angled (usually 45°) so as to direct airflow in a particular direction or to deflect rain or spray. Whilst this can be a useful feature to include in a vent design it should be borne in mind that it will impede airflow, particularly at higher air speeds.
Thin Attenuation Vent Panels
Thin vent panels, or thin screen shields (TSS), are designed for applications where space is limited, and eliminating the use of full size honeycomb vents.
EMI Shielding Dust Filters
Electronic filter and dust shields perform three functions. They attenuate RFI, provide for the passage of cooling air and filter large dust particles from the airflow. They provide maximum dust trapping effectiveness, yet cause reasonably low resistance to air movement.
High performance vents
There are also some types of vent designed for very high levels of performance and / or more arduous conditions. There are two methods of construction that can be used if this is the case.
Machined from solid –
The vent can be machined from a solid aluminium billet or plate. The open area of the vent is created by a drilled matrix of holes that utilises the waveguide beyond cut-off effect of holes that have a diameter approximately one quarter or less of there length.
Fully brazed/solder steel construction –
Alternatively these types of vents may be fabricated from interlocking steel strips that are then fully brazed and then over plated with zinc or tin. This type of construction provides outstanding shielding performance particularly in the ‘H’ field or magnetic region
Low Cost Fan Vent Panels
We stock a range of low cost EMC vents for use with 40mm, 60mm, 80mm, 92mm & 120mm fans. They provide EMC shielding where applications demand a low cost solution, whilst still providing an adequate shielding performance.
These are available ‘off the shelf’ for fast delivery and significantly more cost effective if small volume shielding vents are required.
Honeycomb vent panels are used wherever there is a requirement for a high level of air flow and shielding performance such as
Heating ventilation and air conditioning systems
Cooling high power systems/circuits e.g. radar, RF comms, power supplies, etc
We recommend Electromagnetic Testing Services Ltd to test EMI shielding products in your application.
For more information, please Contact Us