Abstract: A safety circuit for an electric detonator element connected to two electrical leads and having a subsequently arranged detonable charge. The safety circuit includes an electrical component connected in parallel to the detonator element between the two leads, the electrical component having an initial condition wherein the electrical component is at least substantially electrically non-conductive. The electrical component is responsive to a signal having a voltage value above a maximum ignition voltage value for enabling triggering of a detonator element for being converted from the initial condition thereof to a final condition wherein the electrical component provides a short circuit path in parallel to the detonator element so as to prevent improper initiation of the electrical detonator element.

Abstract: In order to avoid embedding a sensitive component in a resinous potting material, as usual, a prefabricated protective housing is used which includes a prefabricated housing body in which the sensitive component is inserted, initially with a clearance at one end of the component. A deformation zone of the housing body is plastically deformed in order to fix the component in place in an axial direction by clamping. Then an elastically deformable lid is attached to the housing body, this lid maintaining the component radially in contact against a seat. The protective housing is especially suited for use in devices which contain explosives because no dangerous working materials are utilized during the encapsulation or encasement process and, consequently, there is no exudation of aggressive resin ingredients.