Abstract: A spark fault tester apparatus includes an electrode; a power supply operatively connected to provide an electrical field at the electrode; a voltage monitoring module operatively connected to measure the intensity of the electrical field at the electrode; a current monitoring module operatively connected to measure a current output of the power supply; and a microprocessor operatively connected to sample the voltage monitoring module and the current monitoring module, and to adjust the power supply. The microprocessor implements a voltage regulation algorithm and a fault typing algorithm, based on samples of the voltage and current monitoring modules, to distinguish among at least two types of insulation defects.

Abstract: A spark tester electrode includes a first bracket that supports a first plurality of filaments and a second bracket that supports a second plurality of filaments. The first and second brackets are mutually disposed at angles toward each other, such that the first plurality of filaments that are supported from the first bracket intermingle with the second plurality of filaments that are supported from the second bracket.