In this paper a real-life case of repair of minor generator stator core surface damage by electro-etching method is presented.
The generator is 120 MVA 3000 rpm 10,5 kV turbo generator. It suffered a cata-strophic stator winding failure on winding end area. The resulting light arc, fire and contamination damaged the stator winding beyond reasonable repair, however the sta-tor core stayed undamaged.
The stator was repaired by full rewinding.