A trigger circuit comprises a first series circuit (16) defined by an electronic switch (17) and an electromagnetic actuator (10). A second series circuit (18) defined by a resistor (19) and a sensor (20) responding to danger situations is arranged in parallel to said first series circuit (16). A tap (24) of said second series circuit (18) is connected with a control electrode (25) of said electronic switch (17). The circuit is of simple configuration and ensures a reliable switching behavior. Even when said sensor (20) is closed again, the trigger state is maintained.