How can EMI be contained?

The problems that this would lead to are obvious, access would be impossible, power unavailable, visibility would be zero and the equipment would rapidly overheat.

We have, therefore, to permit suitable penetrations of the shield to allow cables to pass in and out, to provide airflow and to facilitate the viewing of LED/LCD or CRT displays.

Enclosures for equipment are commonly made from steel, aluminium and, with increasing popularity due to their aesthetic design capabilities, plastic. Plastic enclosures should be coated with a metalized compound applied by vacuum deposition, painting, or sputter coasting. Alternatively, a lining of aluminium or copper foil can provide excellent shielding effectiveness.

In brief, the metal (or metalized) enclosure will, in most instances, require gasketing to seal mating surfaces and to provide the necessary low impedance electrical bond, attenuating vent panels for airflow and shielded windows to prevent the whole ‘open’ area where a display is mounted from representing an unacceptable gap in the shielding.

Inspection panels and doors may be fitted wit ‘soft closure’ gaskets or with CFS (contact finger strip) which also provide high shielding effectiveness with long service life and ease of closure.

Connectors for cable entry should similarly be fitted with gaskets and, where necessary, conductive cable glands to connect with screened cables if these are incorporated in the specification.

The Nolato range is designed to combat radiated interference. Conducted interference, through cables and connections, is a topic encompassing line filters and cable screening and is the domain of specialist manufacturers of screened cables, filters, and screened connectors. These items are outside scope of the Nolato range.