Method for diagnosing a self-blowing switch and diagnostic device

摘要

The method involves triggering a shift operation of a self blowing switch (1) for triggering a pressure wave of filling gas of the switch, and detecting a time-dependant pressure pattern in a region of the switch as reaction on the shift operation. A state of a burn-up nozzle (11) of the switch is determined, where the nozzle is burnt during a shift operation under load for blowing a switching arc with the filling gas. The state of the burn-up nozzle is determined based on the time-dependant pressure pattern. An independent claim is also included for a diagnostic apparatus comprising a pressure sensor.