1. Shields and topological boundaries

With the exception of coaxial cables, the shielding used in electronic equipment subject to electromagnetic constraints has a purely passive function. This criterion means that their presence has no effect on the nominal operation of any equipment supplied by the power grid or by an autonomous source.

Shielding is one of a range of protective devices designed to attenuate electrical and magnetic phenomena, associated in this text with three types of event:

• electromagnetic fields from sources near or far from the equipment;

• Conducted currents and voltages on power supply networks;

• currents derived in the ground or in any conductive structure acting as a global potential reference (GPR).

Shielding and electromagnetic...