Protective device, characterized by the fact that it is constituted by a body of suitable material, such as soapstone that forms a rectangular block that has a longitudinal, rectangular, and perpendicular to the upper major base, there are three holes that reach considered, each having at the opposite base of the body itself one of said holes a larger diameter in its mouth of lower major base, being disposed in each of the end holes and resting on the bottom of the longitudinal depression of the upper major base respective contact sheets preferably type faston projecting laterally and partially, with through hole, which matches the corresponding hole of the end in question of the ceramic body and juxtaposed on the sheet of one of the two ends of the aforementioned body is placed another contact sheet staggered so that one of its ends is supported on the non-projecting end d e the first lámina at the base of the longitudinal regatta, while then it is bent inclined upwards and its free end is left in cantilever carrying the contact plot and all this is fixed through the appropriate rivet that passes through the two matching holes in position with that of the dielectric body, while in the hole of the opposite end to that described; on the fixed contact sheet, a flexible sheet inclined upwards is riveted through the appropriate holes and another resistant sheet passes over and along the middle erectile, its curved end pressing against the free end of the erectile, which tends to maintain, force, constantly separated from the contact plot of the cantilevered end of the sheet of the opposite side described above and anointed the rigid contact sheet as the erectile, as well as the tendency to tighten in separating action to said erectile sheet, are fastened by the appropriate rivet and therefore all lodged against the regatta of the larger upper base of the ceramic body and in the central hole partially emerges a cylindrical wedge of suitable material which is partially housed in a cap uncovered that a part of its total height is filled with a material that when solidified presents enough rigidity to act as a tap n of its lower base and support base of the wedge, the central hole being of different coaxial diameters to allow perfectly the housing of the bushing and that of the wedge of smaller diameter so that it protrudes through the mouth of the central hole of the race longitudinal of the larger upper base tighten against the flexible sheet, force it and raise the tip of the contact erectile sheet until it touches the plot of the cantilever sheet on the opposite side, overcoming in a wedge way the antagonistic action of the separator blade-spring and thus producing the closure of the electric circuit, which automatically opens if for any reason the wedge or its support bush are destroyed during the use of the connected electrical device, since then when the pushing action disappears from the wedge the antagonist blade-spring overcomes the resistance of the flexible sheet and therefore the end of it separates from the contact plot the immediate opening of the electric circuit is produced, a transverse clamp-clamp of the main base of the central hole where the wedge bushing is housed is provided, in order to prevent it from being detached fortuitously from its housing and also to proceed voluntarily to the momentary withdrawal of the flange for the removal of the bushing and wedge by other means if appropriate. (Machine-translation by Google Translate, not legally binding)