A temporary component of current and voltage in an electric circuit which has been disturbed: When using a vacuum switch to close or interrupt a circuit, an electric transient can be increased in the circuit, making the insulation of the course of electricity higher than the rated operation voltage.

Vehicle-type alarm systems can usually detect electric transients in such activities, as starting the engine or opening a door, which can initiate a courtesy light that indicates a disturbance in the circuit that can result in making a warning alert.