The self-extinguishing current limit and the arc-burning time of compensated 20-kV-power-grids

The actual valid self-extinguishing current limit of 20-kV-compensated power grids, written in the VDE 0228 is 60 A. This limit is based on trials from the years 1963 done by M. Erich und H. Heinze. In the year 1981 K. H. Koch presented results of new earth-fault trials. He concluded that the self-extinguishing current increases for larger power grids. An afresh scientific interpretation of both experiments leads to a novel proposal for a self-extinguishing current limit for compensated 20-kV-power-grids. This novel self-extinguishing current limit would allow the extension of current compensated power grids. Further the medium arc-burning time for compensated power grids is discussed.