Abstract: The invention relates to a protective circuit for the protection of the user from overvoltage and overcurrent, in particular for telecommunication installations. Prior art protective circuits comprise a fuse connected into the line connection, and a surge arrester with a heat-sensitive protection device, forming a cross path between the current path of the line connection and the earth conductor, the heat-sensitive protection device disconnecting the cross path in case of excessive power, and connecting it to the earth conductor.In the protective circuit according to the invention, a response of the heat-sensitive protection device (5, 6) will cause disconnection of the cross path of the surge arrester (1, 2) and closing of a short-circuit cross path (7, 8) behind the fuse (3, 4) between the line connection (a, a'; b, b') and the earth conductor (E). The protective circuit can be accommodated in a miniature plug for application in telecommunication installations.

Abstract: A thermal overload protection device for electronic components, in particular for the telecommunication and data technology. The overload device has a spring-elastic shorting link 6 and a melt element 13. Tripping of the shorting link 6 performed in dependence of the fusing process of the melt element 13. In order to obtain a SERVO FAIL SAFE behavior, the spring force of the shorting link 6 is arbitrarily high. Devices 15, 17, separate from each other, are provided, according to the invention, for separately tripping and actuating the shorting link 6.