Measurement of the pre-arcing time and the fulgurite length in hbc fuse in the case of tests performed with an A.C. 100 KVA station

This study deals with a specific test device especially designed to perform tests on HBC fuse on a scale of a non industrial laboratory. In fact it is not possible for most of academic laboratories to build up a device supplying the same current and voltage ranges as in an industrial test station. Moreover the capacitor bank discharges are often used in academic laboratories to test electric fuses. But the main drawback of the capacitor bank is to supply a non 50 Hz-sinusoidal current waveform for one half period only. We present the first measurements performed on experimental HBC fuses using a 100 kVA station built up from a single phase transformer. These first measurements are performed using various fuse elements with the same geometries as in industrial fuses of the middle voltage range. The filling material is silica sand or quartz sand and it is chosen with the same properties as in industrial fuses. The fuse working is studied experimentally on the whole duration of the fuse working which depends on the values chosen for the power factor and the closing angle. The results are given for the pre-arcing time and the fulgurite length. The power factor put in the tests is equal to cos phi~ 0.9 and cos phi ~0.1, and the closing angle is increased from 0 deg to 180 deg. The results are discussed by taking into account the influence of the energy to dissipate, namely the Joule energy and the inductive energy.