PROTECTIVE DEVICE AGAINST EXCESSIVE CURRENTS, IN PARTICULAR FOR RESETTABLE PROTECTION OF A CONTROLLED SWITCH

摘要

The invention concerns a protective device against excessive currents occurring in an electric circuit between a voltage source (2) and a load (3) mounted downstream of said device, comprising first triggering means (7) with high current sensitivity and adapted to be triggered, rapidly, but reversibly, in case of excessive current in the circuit, and second triggering means (8), mounted in parallel with the first, capable of bearing a temporary voltage higher than the power-supply voltage, when the first means (7) are triggered, and of being triggered rapidly and reversibly thereafter. The triggering means are preferably filled conductive polymer components. The invention also concerns a triac (4) switch (1) comprising such a protective device mounted upstream of the triac (4) and a third component mounted on the triac (4) trigger (6).