The present invention relates to an electric protection apparatus comprising at least one switching module fitted on a mounting support, and a control device with an electromagnetic coil juxtaposed with one of the above-mentioned modules, this device comprising a magnetic shield arranged in a plane substantially perpendicular to the plane of the mounting support, said shield being located between the control device and the switching module situated closer to said device, facing the coil of the control device, and comprising at least one ferromagnetic part shaped in such a way that said shield performs magnetic guiding of the arc as soon as separation of the contacts takes place so as to increase the propulsion component of the Laplacian force acting on the arc as soon as separation of the contacts takes place.