Method and apparatus for testing current limited devices

摘要

A method of testing a current limiting device 20 connected between first and second portions of an electrical conductor. The method comprises first generating vibrations in a target frequency band and applying the vibrations to the first portion of the electrical conductor. The vibrations are then detected in the second portion of the electrical conductor and a time at which vibrations arrive in an environment adjacent the second portion of the electrical conductor is determined. The time at which the vibrations in the second portion are detected is compared with the time at which the vibrations arrive in said environment, and a determination is made that the current limiting device 20 is intact if the vibrations in the second portion are detected before the vibrations are determined to arrive in the environment. If the vibrations arrive in the second portion after they arrive in the environment, then the determination is made that the current limiting device 20 has failed.