With the partial discharge (PD) phase-resolving at 0.1 Hz (VLF), BAUR Pruef- und Messtechnik now offers a unique solution for analyzing PDs in medium-voltage cables with immediate effect.
The optional evaluation solution works in conjunction with the new BAUR system software 3.3 and the cable diagnostics systems PHG 70/80 TD/PD. Thanks to the phase-resolving, users can locate PDs exactly as well as differentiate between internal and external PDs. In this way, you can determine whether the cable fault is due to insulation defects or whether, more likely, there is a corona discharge on the surface. While internal PDs primarily occur in the zero crossing range of the test voltage (because the highest voltage change takes place at this point), external partial discharges can be typically found at the maxima of the sinusoid. Phase-resolving also can be applied when PDs have been measured at several locations in the cable. In this case, the operator determines the fault locations that he wants to examine more closely. Subsequently, the screen displays the sinusoid with the PDs occurring there.
For accuracy of results, a constant test voltage, a consistent frequency and a distortion-free sinus shape of the test voltage are a prerequisite.
BAUR Pruef- und Messtechnik GmbH