Abstract: The present invention refers to a system of protection against electric current short circuits and fulminations, apt to be applied on any installation comprising an electric apparatus and a polyphase feeding cable connecting said apparatus to a socket through connection means. According to the invention, the installation comprises a screening of the electric apparatus and/or of the feeding cable, formed by a pair of spaced wire nets being electrically insulated one from the other, a two-phase auxiliary electric line with each phase connected to one of said wire nets, and a cutout circuit associated to said connection means for disconnecting the electric feeding in response to a short circuit between said two wire nets.