good morning from Spain.
In my zone the 15-20kv distribution system is grounded by a resistor that limits the earth current to 1000 or 300 amperes depending on the substation (cables or lines).
I'm analyzing an Oscillography of an earth to ground fault. In tis case the transformer has a 13...
I recently had a problem where a 51N protection saw a sawtooth oscilography (see attached file) and the main distance protecctión 21 didnt measure well beeing in a diferent winding.
In the subestation there where three windings for each phase two for protection and one for meassurement. Each...
